MICROORGANISMS

CROSS-REFERENCE TO RELATED APPLICATIONS

[01] This application claims the benefit of U.S. Provisional Application No.

62/252,971, filed November 9, 2015, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[02] The invention relates to recombinant production of taurine in microbial organisms, and use in feed compositions, in particular for aquaculture, animal feeds and human nutrition.

BACKGROUND

[03] Taurine (2-aminoethanesulfonic acid) is a 2-carbon ( )-amino acid found in a broad swath of organisms, from birds to mammals, fish to plants, fungi and bacteria (McCusker et al. (2014) JNutr Sci 3:e39). While some proteins contain taurine, it does not form peptide bonds due to the lack of a carboxyl group. In fact, taurine is the most abundant free amino acid (FAA) present in animal tissues, constituting 19% of the FAA in the brain, 50% in kidney, and 53% in muscle. (Brosnan et al. (2006) JNutr. 136(6): 16365 -16405)

[04] Taurine is critical in many basic cellular processes, including osmoregulation, membrane stabilization, and anti oxidation. (Honjoh et al. (2010) Amino Acids . 38(4): 1173- 1183; Takeuchi et al. (2000) Biochim Biophys Acta. 1464(2):219-230) In addition, taurine participates in a variety of more complex physiological functions, such as bile conjugation and calcium signaling. (Salze et al. (2015) Aquaculture 437:215-229). Taurine and hypotaurine have also been shown to aid in protein folding (Warskulat et al. (2007) Methods Enzymol 428:439-58; Abe et al. (2015) Amino acids 47(5):909-15; Fujii et al. (2007) J Biochem 141(5):697-707).

[05] While taurine can be detected at high levels in a variety of fish species, some taurine has been suggested as a conditionally essential nutrient for many carnivorous fish species, from trout to snakehead, and its supplementation has been shown to increase their growth rate. (Gibson et al. (2007) Aquaculture 269(l-4):514-524; Wu et al. (2015) Aquae Nutr. 21 (2):214-222) Furthermore, it appears that taurine supplementation can complement the reduction of fishmeal in the feedstock, a critical objective for achieving a more sustainable form of aquaculture.

[06] For cats, dietary taurine is often a necessary addition to feed. Inadequate levels of taurine may cause severe degenerative changes in the retina, visual cortex and brain development. Taurine has also been reported to have anti-epilepsy properties. (Ripps and Shen (2012) Molecular Vision 18:2673-2786)

[07] Chemical synthesis of taurine is undoubtedly the predominant means of production, via a plethora of known synthetic mechanisms. (Salze et al. (2015) Aquaculture 437:215- 229) The biosynthesis of taurine in plant cells has also been described. (US2012/0222148 Al) Contrary to prior belief, a series of recent publications indicate that a large number of bacteria, fungi, and algae contain individual enzymes, or in some cases entire anabolic pathways, which are capable of taurine synthesis. (Tevatia et al. (2015) Algal Res. 9:21-26; Agnello et al. (2013) ACS Chem Biol. 8(10): 2264-2271)

[08] There is a need for a combined protein/taurine feedstock to serve the fields of animal nutrition. The need is especially pressing in aquaculture during the larval stage of fish. Larval feed, which can sit in the water longer than adult feed, can result in significant loss of taurine due to dissipation. Chemically synthesized taurine in crystalline form is particularly susceptible to this process. Enriching rotifers with taurine is an effective solution (Matsunari et al. (2013) Fish Sci. 79(5):815-821), but a potentially uneconomical one, as live feeds tend to be expensive. An alternative strategy is to encapsulate taurine in microparticles, such as lipid-walled capsules (Langdon et al. (2003) Aquaculture 227(1- 4):259-275). Plant-based production systems could achieve this objective by employing the cell membrane as a natural lipid-capsule. This approach is imperfect, however, as direct feeding with plant cells suffers from the anti-nutritional factors found in plant-based feeds. (Francis et al. (2001) Aquaculture 199(3-4): 197-227) Therefore, there exists a need for an aquaculture feed that protects taurine from dissolving in water, while eschewing solutions involving plant-based biosynthesis or live feeds. The invention herein describes just such a solution. BRIEF SUMMARY OF THE INVENTION

[09] In one aspect, non-naturally occurring microorganisms are provided that express one or more polynucleotide(s) expressing exogenous enzyme(s) for production of taurine. For example, a non-naturally occurring microorganism expresses the following enzyme activities: (a) cysteamine (2-aminoethanethiol) di oxygenase (ADO); (b) cysteine dioxygenase (CDO), and cysteine sulfinic acid decarboxylase (CSAD) or glutamate decarboxylase (GAD); (c) 3-mercaptopropionate dioxygenase (p3MDO), and CSAD or GAD; (d) L-serine dehydratase; sulfate adenyltransferase and adenylyl-sulfate kinase (APSK), and/or 3'-phosphoadenosine 5'-phosphosulfate synthase (PAPSS 1)); 3'- phosphoadenylyl sulfate:2-aminoacrylate C-sulfotransferase (PAPS-AS), and CSAD or GAD; (e) cysteate synthase, optionally L-serine dehydratase, and CSAD or GAD; (f) L- cysteine desulfydrase (CD) activity; optionally cystathionine gamma-lyase (CGL) activity; sulfate adenyltransferase and APSK, and/or PAPSS 1); PAPS-AS, and CSAD or GAD; (g) CD) activity; optionally CGL activity; cysteate synthase, and CSAD or GAD; (h) cysteate sulfo-lyase (CuyA), and CSAD or GAD; (i) phosphosulfolactate synthase (ComA), 2- phospho-3-sulfolactate phosphohydrolase (ComB), sulfolactate dehydrogenase (ComC), aspartate aminotransferase (AspAT), and CSAD or GAD; (j) sulfoacetaldehyde acetyltransferase (Xsc) and taurine-pyruvate aminotransferase (Tpa); (k) ComA, ComB, ComC, sulfopyruvate decarboxylase (ComDE), and Tpa; or (1) AspAT, ComDE and Tpa, wherein at least one of said enzyme activities is encoded by an exogenous polynucleotide that is expressed in the microorganism.

[10] In some embodiments, the non-naturally occurring microorganism is derived from a host cell from genera selected from Methylobacterium, Methylomonas , Methylobacter . Methylococcus , Methylosinus , Methylocyctis , Methylomicrobium, Methylomonas,

Methylpophilus , Methylobacillus , Methylobacterium, Hyphomicrobium, Xanthobacter , Bacillus, Paracoccus, Nocardia, Arthrobacter, Rhodopseudomonas , Pseudomonas, Candida, Hansenula, Pichia, Torulopsis, Rhodotorula, Escherichia, and Saccharomyces . For example, the microorganism may be selected from Methylobacterium, Escherichia, Saccharomyces, and Bacillus. In some embodiments, the non-naturally occurring microorganism is a methylotrophic bacterium. For example, the non-naturally occurring microorganism may be aMethylobacterium species, such as but not limited to,

Methylobacterium extorquens.

[11] In some embodiments, the one or more exogenous polynucleotide(s) is/are codon optimized for expression in the microorganism. In some embodiments, the one or more exogenous polynucleotide(s) is/are operably linked to promoter(s) for expression in the microorganism.

[12] In some embodiments, the non-naturally occurring microorganism includes deletion of one or more genes that encode enzyme(s) that degrade taurine or the taurine precursor cysteate or sulfoacetaldehyde or modification of one or more genes that encode enzyme(s) that degrade taurine, cysteate, or sulfoacetaldehyde such that activity of the one or more enzyme(s) that degrade taurine, cysteate, or sulfoacetaldehyde is lower than in the microorganism parent strain from which the non-naturally microorganism is derived. In some embodiments, the one or more enzyme(s) that degrade taurine, cysteate, or sulfoacetaldehyde includes taurine dehydrogenase, taurine dioxygenase, Xsc, CuyA, Tpa, and/or gamma-glutamyltransferase.

[13] In some embodiments, the non-naturally occurring microorganism is genetically modified or artificially pre-selected to produce elevated levels of a carotenoid compound relative to the corresponding unmodified or unselected microorganism. For example, the microorganism may produce elevated levels of one or more carotenoid compound(s) selected from β-carotene, lycopene, rhodopsin, zeaxanthin, lutein, canthaxanthin, astaxanthin, and sprilloxanthin, in comparison to the host cell from which the carotenoid producing microorganism is derived.

[14] In some embodiments, the non-naturally occurring microorganism accumulates intracellular taurine and/or hypotaurine, wherein the taurine and/or hypotaurine aids in the folding of one or more native and/or heterologous protein(s), e.g., for the purpose of increased enzymatic activity and/or protein yield in comparison to the parent

microorganism from which the non-naturally occurring microorganism is derived, e.g., a parent microorganism that does not include the one or more exogenous polynucleotide(s).

[15] In another aspect, methods are provided for producing biomass that includes taurine and/or taurine precursors such as cysteate, sulfoacetaldehyde, and/or hypotaurine. The methods include culturing a non-naturally occurring microorganism as described herein in a culture medium under conditions suitable for growth of the microorganism and expression of exogenous enzyme(s) for production of taurine and/or taurine precursors, wherein biomass comprising taurine and/or taurine precursors is produced in the culture.

[16] In another aspect, a feed or nutritional supplement is provided that includes taurine- and/or taurine precursor-containing biomass produced as described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[17] Figure 1 depicts an embodiment of a biosynthetic pathway for production of taurine from cysteamine.

[18] Figure 2 depicts an embodiment of a biosynthetic pathway for production of taurine from L-cysteine.

[19] Figure 3 depicts an embodiment of a biosynthetic pathway for production of taurine from L-cysteine.

[20] Figure 4 depicts an embodiment of a biosynthetic pathway for production of taurine from L-serine.

[21] Figure 5 depicts an embodiment of a biosynthetic pathway for production of taurine from L-phosphoserine or L-serine.

[22] Figure 6 depicts an embodiment of a biosynthetic pathway for production of taurine from L-cysteine.

[23] Figure 7 depicts an embodiment of a biosynthetic pathway for production of taurine from L-cysteine.

[24] Figure 8 depicts an embodiment of a biosynthetic pathway for production of taurine from pyruvate.

[25] Figure 9 depicts an embodiment of a biosynthetic pathway for production of taurine from phosphoenolpyruvate.

[26] Figure 10 depicts an embodiment of a biosynthetic pathway for production of taurine from acetyl phosphate.

[27] Figure 11 depicts an embodiment of a biosynthetic pathway for production of taurine from phosphoenolpyruvate.

[28] Figure 12 depicts an embodiment of a biosynthetic pathway for production of taurine through taurine-pyruvate aminotransferase.

[29] Figure 13 depicts taurine and cysteate degradation pathways. DETAILED DESCRIPTION

[30] The invention described herein addresses the dual challenge of producing taurine from an inexpensive feedstock, and encapsulating it to prevent dissolution in water for aquaculture. Microbial systems for taurine production are described as well as feed products in which the taurine is encapsulated in a natural lipid bilayer (microbial cells).

[31] Provided herein are non-naturally occurring microorganisms, e.g., bacteria, yeast, Archaea, that are capable of producing taurine and/or the taurine precursor(s), e.g., hypotaurine or cysteate. Also provided are methods of engineering and culturing such microorganisms, methods of using such microorganisms to produce taurine, and methods of producing taurine-containing compositions, such as feed compositions that contain the microorganisms or compositions that contain taurine recovered from such organisms.

[32] One aspect pertains to the field of aquaculture. Another aspect is the field of pet foods, for example, for cats and dogs. A further aspect is in the field of human nutrition and supplements. More specifically, aquaculture feeds, pet food, and nutritional supplement compositions are provided that include taurine-containing microbial biomass and a complete protein nutrition, that is, containing most or all amino acids necessary for healthy growth of the animal to which it is administered. In some embodiments, the aquaculture feed compositions herein contain one or more carotenoid(s) produced by the microorganism that produces taurine and/or taurine precursor(s), e.g. , hypotaurine or cysteate. The microbial biomass can be blended with other ingredients to form a portion or whole of a feed, or may be consumed directly as a protein-rich powder.

[33] Another aspect pertains to the field of industrial protein production. Osmolytes such as betaine, glycine, trimethylamine N-Oxide (TMAO), and taurine can aid in protein folding (Warskulat et al. (2007) Methods Enzymol 428:439-58; Abe et al. (2015) Amino acids 47(5):909-15; Fujii et al. (2007) J Biochem 141(5):697-707). Microorganisms engineered to accumulate intracellular taurine as a chemical chaperone could produce higher yields or more active proteins of interest. As antioxidants, taurine, hypotaurine, and their precursors also promote protein activity by limiting protein inactivation through oxidation (Oliveira et al. (2010) Pharmacological Reports 62: 185-193; Aruoma et al. (1988) Biochem J 256:251-55; Bucolo et al. (2016) Acta Ophthalmologic 95(256); Patel et al. (2016) Exp Toxic Pathol 68(2-3): 103-12; Fontana et al. (2004) Neurochemical Research 29(1): 111-116). Definitions

[34] Unless defined otherwise herein, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Singleton, et al. Dictionary of Microbiology and Molecular Biology, second ed., John Wiley and Sons, New York (1994), and Hale & Markham. The Harper Collins Dictionary of Biology. Harper Perennial, NY (1991) provide one of skill with a general dictionary of many of the terms used in this invention. Any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention.

[35] The practice of the present invention will employ, unless otherwise indicated, conventional techniques of molecular biology (including recombinant techniques), microbiology, cell biology, and biochemistry, which are within the skill of the art. Such techniques are explained fully in the literature, for example, Molecular Cloning: A

Laboratory Manual, second edition (Sambrook et al, 1989); Oligonucleotide Synthesis (M. J. Gait, ed., 1984; Current Protocols in Molecular Biology (F. M. Ausubel et al, eds., 1994); PCR: The Polymerase Chain Reaction (Mullis et al, eds., 1994); and Gene Transfer and Expression: A Laboratory Manual (Kriegler, 1990).

[36] Numeric ranges provided herein are inclusive of the numbers defining the range.

[37] Unless otherwise indicated, nucleic acids are written left to right in 5' to 3' orientation; amino acid sequences are written left to right in amino to carboxy orientation, respectively.

[38] "A," "an" and "the" include plural references unless the context clearly dictates otherwise.

[39] As used herein, the term "polynucleotide" refers to a polymeric form of nucleotides of any length and any three-dimensional structure and single- or multi-stranded (e.g., single-stranded, double-stranded, triple-helical, etc.), which contain

deoxyribonucleotides, ribonucleotides, and/or analogs or modified forms of

deoxyribonucleotides or ribonucleotides, including modified nucleotides or bases or their analogs. Because the genetic code is degenerate, more than one codon may be used to encode a particular amino acid, and the present invention encompasses polynucleotides which encode a particular amino acid sequence. Any type of modified nucleotide or nucleotide analog may be used, so long as the polynucleotide retains the desired functionality under conditions of use, including modifications that increase nuclease resistance (e.g., deoxy, 2'-0-Me, phosphorothioates, etc.). Labels may also be incorporated for purposes of detection or capture, for example, radioactive or nonradioactive labels or anchors, e.g., biotin. The term polynucleotide also includes peptide nucleic acids (PNA). Polynucleotides may be naturally occurring or non-naturally occurring. The terms

"polynucleotide," "nucleic acid," and "oligonucleotide" are used herein interchangeably. Polynucleotides may contain RNA, DNA, or both, and/or modified forms and/or analogs thereof. A sequence of nucleotides may be interrupted by non-nucleotide components. One or more phosphodiester linkages may be replaced by alternative linking groups. These alternative linking groups include, but are not limited to, embodiments wherein phosphate is replaced by P(0)S ("thioate"), P(S)S ("dithioate"), (0)NR.sub.2 ("amidate"), P(0)R, P(0)OR', CO or CH.sub.2 ("formacetal"), in which each R or R is independently H or substituted or unsubstituted alkyl (1-20 C) optionally containing an ether (— 0~) linkage, aryl, alkenyl, cycloalkyl, cycloalkenyl or araldyl. Not all linkages in a polynucleotide need be identical. Polynucleotides may be linear or circular or comprise a combination of linear and circular portions.

[40] As used herein, "polypeptide" refers to a composition comprised of amino acids and recognized as a protein by those of skill in the art. The conventional one-letter or three- letter code for amino acid residues is used herein. The terms "polypeptide" and "protein" are used interchangeably herein to refer to polymers of amino acids of any length. The polymer may be linear or branched, it may comprise modified amino acids, and it may be interrupted by non-amino acids. The terms also encompass an amino acid polymer that has been modified naturally or by intervention; for example, disulfide bond formation, glycosylation, lipidation, acetylation, phosphorylation, or any other manipulation or modification, such as conjugation with a labeling component. Also included within the definition are, for example, polypeptides containing one or more analogs of an amino acid (including, for example, unnatural amino acids, etc.), as well as other modifications known in the art.

[41] As used herein, a "vector" refers to a polynucleotide sequence designed to introduce nucleic acids into one or more cell types. Vectors include cloning vectors, expression vectors, shuttle vectors, plasmids, phage particles, cassettes and the like. [42] As used herein, the term "expression" refers to the process by which a polypeptide is produced based on the nucleic acid sequence of a gene. The process includes both transcription and translation.

[43] As used herein, "expression vector" refers to a DNA construct containing a DNA coding sequence (e.g., gene sequence) that is operably linked to one or more suitable control sequence(s) capable of effecting expression of the coding sequence in a host. Such control sequences include a promoter to effect transcription, an optional operator sequence to control such transcription, a sequence encoding suitable mRNA ribosome binding sites, and sequences which control termination of transcription and translation. The vector may be a plasmid, a phage particle, or simply a potential genomic insert. Once transformed into a suitable host, the vector may replicate and function independently of the host genome, or may, in some instances, integrate into the genome itself. The plasmid is the most commonly used form of expression vector. However, the invention is intended to include such other forms of expression vectors that serve equivalent functions and which are, or become, known in the art.

[44] A "promoter" refers to a regulatory sequence that is involved in binding RNA polymerase to initiate transcription of a gene. A promoter may be an inducible promoter or a constitutive promoter. An "inducible promoter" is a promoter that is active under environmental or developmental regulatory conditions.

[45] The term "operably linked" refers to a juxtaposition or arrangement of specified elements that allows them to perform in concert to bring about an effect. For example, a promoter is operably linked to a coding sequence if it controls the transcription of the coding sequence.

[46] "Under transcriptional control" is a term well understood in the art that indicates that transcription of a polynucleotide sequence depends on its being operably linked to an element which contributes to the initiation of, or promotes transcription.

[47] "Under translational control" is a term well understood in the art that indicates a regulatory process which occurs after mRNA has been formed.

[48] A "gene" refers to a DNA segment that is involved in producing a polypeptide and includes regions preceding and following the coding regions as well as intervening sequences (introns) between individual coding segments (exons). [49] As used herein, the term "host cell" refers to a cell or cell line into which a recombinant expression vector for production of a polypeptide may be transfected for expression of the polypeptide. Host cells include progeny of a single host cell, and the progeny may not necessarily be completely identical (in morphology or in total genomic DNA complement) to the original parent cell due to natural, accidental, or deliberate mutation. A host cell includes cells transfected or transformed in vivo with an expression vector.

[50] The term "recombinant," refers to genetic material (i.e., nucleic acids, the polypeptides they encode, and vectors and cells comprising such polynucleotides) that has been modified to alter its sequence or expression characteristics, such as by mutating the coding sequence to produce an altered polypeptide, fusing the coding sequence to that of another gene, placing a gene under the control of a different promoter, expressing a gene in a heterologous organism, expressing a gene at a decreased or elevated levels, expressing a gene conditionally or constitutively in manner different from its natural expression profile, and the like. Generally recombinant nucleic acids, polypeptides, and cells based thereon, have been manipulated by man such that they are not identical to related nucleic acids, polypeptides, and cells found in nature.

[51] A "signal sequence" refers to a sequence of amino acids bound to the N-terminal portion of a protein which facilitates the secretion of the mature form of the protein from the cell. The mature form of the extracellular protein lacks the signal sequence which is cleaved off during the secretion process.

[52] The term "selective marker" or "selectable marker" refers to a gene capable of expression in a host cell that allows for ease of selection of those hosts containing an introduced nucleic acid or vector. Examples of selectable markers include but are not limited to antimicrobial substances (e.g. , hygromycin, bleomycin, or chloramphenicol) and/or genes that confer a metabolic advantage, such as a nutritional advantage, on the host cell.

[53] The term "derived from" encompasses the terms "originated from," "obtained from," "obtainable from," "isolated from," and "created from," and generally indicates that one specified material finds its origin in another specified material or has features that can be described with reference to the another specified material. [54] The term "culturing" refers to growing a population of cells, e.g., microbial cells, under suitable conditions for growth, in a liquid or solid medium.

[55] The term "heterologous" or "exogenous," with reference to a polynucleotide or protein, refers to a polynucleotide or protein that does not naturally occur in a specified cell, e.g., a host cell. It is intended that the term encompass proteins that are encoded by naturally occurring genes, mutated genes, and/or synthetic genes. In contrast, the term "homologous," with reference to a polynucleotide or protein, refers to a polynucleotide or protein that occurs naturally in the cell.

[56] The term "introduced," in the context of inserting a nucleic acid sequence into a cell, includes "transfection," "transformation," or "transduction" and refers to the incorporation of a nucleic acid sequence into a eukaryotic or prokaryotic cell wherein the nucleic acid sequence may be incorporated into the genome of the cell (e.g., chromosome, plasmid, plastid, or mitochondrial DNA), converted into an autonomous replicon, or transiently expressed.

[57] "Transfection" or "transformation" refers to the insertion of an exogenous polynucleotide into a host cell. The exogenous polynucleotide may be maintained as a non- integrated vector, for example, a plasmid, or alternatively, may be integrated into the host cell genome. The term "transfecting" or "transfection" is intended to encompass all conventional techniques for introducing nucleic acid into host cells. Examples of transfection techniques include, but are not limited to, calcium phosphate precipitation, DEAE-dextran-mediated transfection, lipofection, electroporation, and microinjection.

[58] As used herein, the terms "transformed," "stably transformed," and "transgenic" refer to a cell that has a non-native (e.g. , heterologous) nucleic acid sequence integrated into its genome or as an episomal plasmid that is maintained through multiple generations.

[59] The terms "recovered," "isolated," "purified," and "separated" as used herein refer to a material (e.g., a protein, nucleic acid, or cell) that is removed from at least one component with which it is naturally associated. For example, these terms may refer to a material which is substantially or essentially free from components which normally accompany it as found in its native state, such as, for example, an intact biological system.

[60] A "signal sequence" (also termed "presequence," "signal peptide," "leader sequence," or "leader peptide") refers to a sequence of amino acids at the amino terminus of a nascent polypeptide that targets the polypeptide to the secretory pathway and is cleaved from the nascent polypeptide once it is translocated in the endoplasmic reticulum membrane.

[61] Related (and derivative) proteins encompass "variant" proteins. Variant proteins differ from a parent protein and/or from one another by a small number of amino acid residues. In some embodiments, the number of different amino acid residues is any of about 1, 2, 3, 4, 5, 10, 20, 25, 30, 35, 40, 45, or 50. In some embodiments, variants differ by about 1 to about 10 amino acids. Alternatively or additionally, variants may have a specified degree of sequence identity with a reference protein or nucleic acid, e.g., as determined using a sequence alignment tool, such as BLAST, ALIGN, and CLUSTAL (see, infra). For example, variant proteins or nucleic acid may have at least about 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or even 99.5% amino acid sequence identity with a reference sequence.

[62] As used herein, the term "analogous sequence" refers to a polypeptide sequence within a protein that provides a similar function, tertiary structure, and/or conserved residues with respect to a reference protein. For example, in epitope regions that contain an alpha helix or a beta sheet structure, replacement amino acid(s) in an analogous sequence maintain the same structural element. In some embodiments, analogous sequences are provided that result in a variant enzyme exhibiting a similar or improved function with respect to the parent protein from which the variant is derived.

[63] As used herein, "homologous protein" refers to a protein that has similar function and/or structure as a reference protein. Homologs may be from evolutionarily related or unrelated species. In some embodiments, a homolog has a quaternary, tertiary and/or primary structure similar to that of a reference protein, thereby potentially allowing for replacement of a segment or fragment in the reference protein with an analogous segment or fragment from the homolog, with reduced disruptiveness of structure and/or function of the reference protein in comparison with replacement of the segment or fragment with a sequence from a non-homologous protein.

[64] As used herein, "wild-type," "native," and "naturally-occurring" proteins are those found in nature. The terms "wild-type sequence" refers to an amino acid or nucleic acid sequence that is found in nature or naturally occurring. In some embodiments, a wild-type sequence is the starting point of a protein engineering project, for example, production of variant proteins.

[65] The phrases "substantially similar" and "substantially identical" in the context of at least two nucleic acids or polypeptides typically means that a polynucleotide, polypeptide, or region or domain of a polypeptide that comprises a sequence that has at least about 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or even 99.5% sequence identity, in comparison with a reference (e.g., wild-type) polynucleotide, polypeptide, or region or domain of a polypeptide. A region or domain of a polypeptide may contain, for example, at least about 20, 50, 100, or 200 amino acids within a longer polypeptide sequence. Sequence identity may be determined using known programs such as BLAST, ALIGN, and CLUSTAL using standard parameters. (See, e.g., Altshul et al. (1990) J. Mol. Biol. 215:403-410; Henikoff et al. (1989) Proc. Natl. Acad. Sci. 89: 10915; Karin et al. (1993) Proc. Natl. Acad. Sci. 90:5873; and Higgins et al. (1988) Gene 73:237). Software for performing BLAST analyses is publicly available through the National Center for Biotechnology Information. Also, databases may be searched using FASTA (Person et al. (1988) Proc. Natl. Acad. Sci. 85:2444-2448.) In some embodiments, substantially identical polypeptides differ only by one or more conservative amino acid substitutions. In some embodiments, substantially identical polypeptides are immunologically cross- reactive. In some embodiments, substantially identical nucleic acid molecules hybridize to each other under stringent conditions (e.g., within a range of medium to high stringency).

[66] The term "carotenoid" is understood in the art to refer to a structurally diverse class of pigments derived from isoprenoid pathway intermediates. The commitment step in carotenoid biosynthesis is the formation of phytoene from geranylgeranyl pyrophosphate. Carotenoids can be acyclic or cyclic, and may or may not contain oxygen, so that the term carotenoids include both carotenes and xanthophylls. In general, carotenoids are hydrocarbon compounds having a conjugated polyene carbon skeleton formally derived from the five-carbon compound IPP, including triterpenes (C30 diapocarotenoids) and tetraterpenes (C40 carotenoids) as well as their oxygenated derivatives and other compounds that are, for example, C35, C50, C60, C70, Cso in length or other lengths. Many carotenoids have strong light absorbing properties and may range in length in excess of C200- C30 diapocarotenoids typically consist of six isoprenoid units joined in such a manner that the arrangement of isoprenoid units is reversed at the center of the molecule so that the two central methyl groups are in a 1 ,6-positional relationship and the remaining non-terminal methyl groups are in a 1 ,5-positional relationship. Such C30 carotenoids may be formally derived from the acyclic C30H42 structure, having a long central chain of conjugated double bonds, by: (i) hydrogenation (ii) dehydrogenation, (iii) cyclization, (iv) oxidation, (v) esterification/glycosylation, or any combination of these processes. C40 carotenoids typically consist of eight isoprenoid units joined in such a manner that the arrangement of isoprenoid units is reversed at the center of the molecule so that the two central methyl groups are in a 1 ,6-positional relationship and the remaining non-terminal methyl groups are in a 1 ,5-positional relationship. Such C40 carotenoids may be formally derived from the acyclic C40H56 structure, having a long central chain of conjugated double bonds, by (i) hydrogenation, (ii) dehydrogenation, (iii) cyclization, (iv) oxidation, (v)

esterification/glycosylation, or any combination of these processes. The class of C40 carotenoids also includes certain compounds that arise from rearrangements of the carbon skeleton, or by the (formal) removal of part of this structure. More than 600 different carotenoids have been identified in nature. Carotenoids include but are not limited to:

antheraxanthin, adonirubin, adonixanthin, astaxanthin, canthaxanthin, capsorubrin, β- cryptoxanthin, a-carotene, β-carotene, β,ψ-carotene, δ-carotene, ε-carotene, echinenone, 3- hydroxyechinenone, 3 '-hydroxy echinenone, γ-carotene, ψ-carotene, 4-keto-Y-carotene, ζ- carotene, a-cryptoxanthin, deoxyflexixanthin, diatoxanthin, 7,8-didehydroastaxanthin, didehydrolycopene, fucoxanthin, fucoxanthinol, isorenieratene, β-isorenieratene, lactucaxanthin, lutein, lycopene, myxobactone, neoxanthin, neurosporene,

hydroxyneurosporene, peridinin, phytoene, rhodopin, rhodopin glucoside, 4-keto- rubixanthin,siphonaxanthin, spheroidene, spheroidenone, spirilloxanthin, torulene, 4-keto- torulene, 3-hydroxy-4-keto-torulene, uriolide, uriolide acetate, violaxanthin, zeaxanthin-β- diglucoside, zeaxanthin, and C30 carotenoids. Additionally, carotenoid compounds include derivatives of these molecules, which may include hydroxy-, methoxy-, 0x0-, epoxy-, carboxy-, or aldehydic functional groups. Further, included carotenoid compounds include ester (e.g., glycoside ester, fatty acid ester) and sulfate derivatives (e.g., esterified xanthophylls).

[67] The "isoprenoid pathway" is understood in the art to refer to a metabolic pathway that either produces or utilizes the five-carbon metabolite isopentyl pyrophosphate (IPP). As discussed herein, two different pathways can produce the common isoprenoid precursor IPP— the "mevalonate pathway" and the "non-mevalonate pathway." The term "isoprenoid pathway" is sufficiently general to encompass both of these types of pathway. Biosynthesis of isoprenoids from IPP occurs by polymerization of several five-carbon isoprene subunits. Isoprenoid metabolites derived from IPP vary greatly in chemical structure, including both cyclic and acyclic molecules. Isoprenoid metabolites include, but are not limited to, monoterpenes, sesquiterpenes, diterpenes, sterols, and polyprenols such as carotenoids.

[68] The term "isoprenoid compound" refers to any compound which is derived via the pathway beginning with isopentenyl pyrophosphate (IPP) and formed by the head-to-tail condensation of isoprene units which may be of 5, 10, 15, 20, 30 or 40 carbons in length. There term "isoprenoid pigment" refers to a class of isoprenoid compounds which typically have strong light absorbing properties.

[69] The term "feed premix" refers to the crude mixture of aquaculture feed or animal/pet food components prior to processing, optionally at high temperature, into an aquaculture feed or animal or pet food composition that is in the form of pellets or flakes.

[70] An aquaculture feed composition is used in the production of an "aquaculture product," wherein the product is a harvestable aquacultured species (e.g., finfish, crustaceans), which is often sold for human consumption. For example, salmon are intensively produced in aquaculture and thus are aquaculture products. Aquaculture compositions may also be used as feed for aquaculture feed organisms such as small fish like krill, rotifers, and the like, that are food sources for larger aquaculture organisms such as carnivorous fish. In addition, aquaculture compositions described herein can be used as feed for ornamental fish, shrimp, hobbyist aquaculture, and the like, that are not intended as food for other organisms.

[71] The term "aquaculture meat product" refers to food products intended for human consumption comprising at least a portion of meat from an aquaculture product as defined above. An aquaculture meat product may be, for example, a whole fish or a filet cut from a fish, each of which may be consumed as food. In some embodiments, such a product can be referred to as a fish or seafood product.

[72] The term "biomass" refers to microbial cellular material. Biomass may be produced naturally, or may be produced from the fermentation of a native host or a recombinant production host. The biomass may be in the form of whole cells, whole cell lysates, homogenized cells, partially hydrolyzed cellular material, and/or partially purified cellular material (e.g., microbially produced oil).

[73] The term "processed biomass" refers to biomass that has been subjected to additional processing such as drying, pasteurization, disruption, etc., each of which is discussed in greater detail below.

[74] The term "C-l carbon substrate" refers to any carbon-containing molecule that lacks a carbon-carbon bond. Examples are methane, methanol, formaldehyde, formic acid, formate, methylated amines (e.g., mono-, di-, and tri- methyl amine), methylated thiols, and carbon dioxide.

[75] The term "CI metabolizer" refers to a microorganism that has the ability to use a single carbon substrate as a sole source of energy and biomass. CI metabolizers will typically be methylotrophs and/or methanotrophs capable of growth.

[76] The term "methylotroph" means an organism capable of oxidizing organic compounds which do not contain carbon-carbon bonds. Where the methylotroph is able to oxidize CH4, the methylotroph is also a methanotroph.

[77] The term "methanotroph" means a prokaryote capable of utilizing methane as a substrate. Complete oxidation of methane to carbon dioxide occurs by aerobic degradation pathways. Typical examples of methanotrophs useful in the present invention include but are not limited to the genera Methylomonas, Methylobacter , Methylococcus , and

Methylosinus .

[78] The term "high growth methanotrophic bacterial strain" refers to a bacterium capable of growth using methane as its sole carbon and energy source.

Microorganisms

[79] Non-naturally occurring microorganisms are provided for production of taurine or the taurine precursors hypotaurine, cysteate, or sulfoacetaldehyde. Non-naturally occurring, e.g., recombinant, microorganisms herein include, e.g., bacteria, yeast, Archaea, that have been engineered to express at least one (i.e. , one or more) enzyme(s) for biosynthesis of taurine or taurine precursors and that produce taurine or taurine precursors when cultured under conditions suitable for microbial growth and taurine production.

[80] Non-naturally occurring microorganisms as described herein include one or more exogenous polynucleotide(s) that encode and express one or more enzyme or enzyme activity for biosynthesis of taurine or the taurine precursors cysteate, sulfoacetaldehyde, or hypotaurine. The exogenous polynucleotide(s) may include one or more coding sequence for one or more enzyme or enzyme activity for biosynthesis of taurine or taurine precursors, operably linked to one or more promoter for expression in the non-naturally occurring microorganism. Such promoters may include, but are not limited to, P R (e.g., SEQ ID NO:42), P Lac (e.g., SEQ ID NO:41), P tac (e.g. , SEQ ID NO:39), P tacA (e.g. , SEQ ID NO:40), PmxaF (e.g. , SEQ ID NO:43), P rrnB, and P T7. In some embodiments, the polynucleotide(s) are codon optimized for expression in the microorganism.

[81] In some embodiments, the non-naturally occurring microorganism includes one or more exogenous and/or endogenous polynucleotide(s) that encodes one or more enzymes or enzyme activities for taurine biosynthesis, as described herein, that has been modified for improved stability and/or activity relative to the stability and/or activity of the enzyme or enzyme activity in the host cell from which it is derived or relative to the wild-type stability and/or activity of the enzyme or enzyme activity. For example, the non-naturally occurring microorganism may express a variant of an enzyme of taurine biosynthesis that has greater stability and/or activity than the wild-type enzyme from which it is derived.

[82] In some embodiments, the host cell from which a non-naturally occurring microorganism as described herein is derived has one or more endogenous taurine, cysteate, or sulfoacetaldehyde degrading activity, for example, but not limited to, taurine

dehydrogenase, Tpa, CuyA, gamma-glutamyltransferase, Xsc, and/or taurine dioxygenase. In some embodiments, the non-naturally occurring microorganism includes deletion of one or more genes that encode taurine, cysteate, or sulfoacetaldehyde degrading enzyme(s). In some embodiments, the host cell from which a non-naturally occurring microorganism includes modification of one or more genes that encode taurine, cysteate, or

sulfoacetaldehyde degrading enzyme(s), such that the taurine, cysteate, or

sulfoacetaldehyde degrading activity of the enzyme(s) is lower in the non-naturally occurring microorganism than in the host cell from which it is derived. In some embodiments, the host cell is Methylobacterium extorquens and the non-naturally occurring microorganism derived from the host cell includes deletion or modification of the gene that encodes gamma-glutamyltransferase in the host cell.

[83] In certain embodiments, the host cell comprises one or more of endogenous genes in the described pathway. In certain embodiments, the host cell is modified so that one or more genes producing enzymes that divert compounds and taurine precursors away from a taurine biosynthetic pathway are blocked or deleted. In certain embodiments, the one or more blocked or deleted genes are selected from genes involved in the degradation of taurine, cysteate, or sulfoacetaldehyde. In certain embodiments, the host cell is a spontaneous mutant whose rate of growth is increased relative to a corresponding non- mutant. In certain embodiments, the host cell is cultured under stress conditions selected from light depletion, nutrient depletion, nitrogen depletion, high salt, or a chemical that inhibits growth of the host cell, wherein the stress conditions induce changes in gene expression leading to increased taurine or taurine precursor production.

[84] In some embodiments, the non-naturally occurring microorganism or the host cell from which the non-naturally occurring microorganism is derived is genetically modified or artificially pre-selected to produce elevated levels of one or more carotenoid compound(s) relative to the corresponding unmodified or unselected microorganism. The one or more carotenoid compound(s) may include, but are not limited to, β-carotene, lycopene, zeaxanthin, lutein, canthaxanthin, rhodopin, astaxanthin, and/or sprilloxanthin. Non- limiting examples of host cells that produce elevated levels of one or more carotenoid compound(s) and methods for producing such microorganisms are provided in

WO2015/021352 A2.

[85] Non-limiting examples of genera from which the non-naturally occurring microorganism may be derived include Methylobacterium, Methylomonas , Methylobacter . Methylococcus , Methylosinus , Methylocyctis , Methylomicrobium, Methylomonas,

Methylpophilus , Methylobacillus , Methylobacterium, Hyphomicrobium, Xanthobacter , Bacillus, Paracoccus, Nocardia, Arthrobacter , Rhodopseudomonas , Pseudomonas, Candida, Hansenula, Pichia, Torulopsis, Rhodotorula, Escherichia, and Saccharomyces . Non-limiting examples of microbial species from which the non-naturally occurring microorganism may be derived include Methylobacterium extorquens {e.g. , strains AMI, DM4, CM4, PA1, or BJ001 (formerly Methylobacterium populi)), Methylobacterium radiotolerans, Methylobacterium nodulans, Methylobacterium spp. 4-46, and Escherichia coli.

[86] In some embodiments, the non-naturally occurring microorganism is a methylotrophic bacterium. Conversion of cvsteamine to taurine

[87] In some embodiments, a non-naturally occurring microorganism is provided that expresses an exogenous enzyme activity of 2-aminoethanol (cysteamine) dioxygenase (ADO) (EC 1.13.11.19), which converts cysteamine to hypotaurine, for biosynthesis of taurine, as shown in Fig. 1.

[88] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ADO comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 44, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:44. In some embodiments, the polynucleotide that encodes ADO comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:45 or SEQ ID NO:57 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:45 or SEQ ID NO:57. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:57.

[89] In some embodiments, the non-naturally occurring microorganism is a

Methylobacterium, Escherichia, Saccharomyces , or Bacillus microorganism that includes an exogenous polynucleotide that encodes ADO.

Conversion of cysteine to taurine via CDO

[90] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of cysteine to taurine via the enzyme cysteine dioxygenase (CDO), for example, exogenous enzyme(s) of the CDO/CSAD or GAD pathway for biosynthesis of taurine. The CDO/CSAD or GAD pathway for taurine biosynthesis is shown schematically in Fig. 2.

[91] In some embodiments, the non-naturally occurring microorganism that expresses exogenous enzyme activities of the CDO/CSAD or GAD pathway is not of genera

Escherichia or species Escherichia coli. In some embodiments, the non-naturally occurring microorganism is not of genera Saccharomyces or species Saccharomyces cerevisiae.

[92] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cysteine dioxygenase (CDO) (EC 1.13.11.20); and cysteine sulfinic acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the

microorganism has been transformed. In some embodiments, CDO and CSAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one or two exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of CDO and CSAD enzymes or enzyme activities is encoded an exogenous polynucleotide in the microorganism and the remaining activity is endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e., not expressed from an exogenous polynucleotide. In one embodiment, the microorganism expresses an endogenous CSAD activity and CDO is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous CDO activity and CSAD is encoded by an exogenous polynucleotide in the microorganism.

[93] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cysteine dioxygenase (CDO) (EC 1.13.11.20); and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, CDO and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one or two exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of CDO and GAD enzymes or enzyme activities is encoded by an exogenous polynucleotide in the

microorganism and the remaining activity is endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from an exogenous polynucleotide. In one embodiment, the microorganism expresses an

endogenous GAD activity and CDO is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous CDO activity and GAD is encoded by an exogenous polynucleotide in the microorganism.

[94] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CDO comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 15, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 15. In some embodiments, the polynucleotide that encodes CDO comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 16, SEQ ID NO:50, or SEQ ID NO:58 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 16, SEQ ID NO:50, or SEQ ID NO:58. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:58.

[95] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CDO comprising or consisting of the amino acid sequence depicted in SEQ ID NO:35, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:35. In some embodiments, the polynucleotide that encodes CDO comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 36, SEQ ID NO: 51, or SEQ ID NO: 59 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:36, SEQ ID NO:51, or SEQ ID NO:59. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ. NO:51 or SEQ ID NO: 59.

[96] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40,45,50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:53 or SEQ ID NO:54.

[97] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[98] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CDO and CSAD. In another embodiment, a non-naturally occurring Methylobacterium

microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CDO and GAD.

[99] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes an exogenous polynucleotide encoding CDO. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CDO and CSAD.

[100] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes an exogenous polynucleotide encoding CDO. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CDO and CSAD.

[101] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes an exogenous polynucleotide encoding CSAD.

Conversion of cysteine to taurine via p3MDO

[102] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of cysteine to taurine via the enzyme 3-mercaptopropionate dioxygenase (p3MDO), for example, exogenous enzyme(s) of the p3MDO/CSAD or GAD pathway for biosynthesis of taurine. The p3MDO/CSAD or GAD pathway for taurine biosynthesis is shown schematically in Fig. 3

[103] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: 3-mercaptopropionate dioxygenase (MDO; p3MDO) (EC 1.13.11.-); and cysteine sulfinic acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, p3MDO and CSAD enzymes or enzyme activities are encoded by one or more exogenous

polynucleotide(s) (e.g., one or two, exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of p3MDO and CSAD enzymes or enzyme activities is encoded by an exogenous polynucleotide in the microorganism and the remaining activity is endogenously expressed in the host cell from which the non-naturally occurring

microorganism is derived, i.e. , not expressed from an exogenous polynucleotide. In one embodiment, the microorganism expresses an endogenous CSAD activity and p3MDO is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous p3MDO activity and CSAD is encoded by an exogenous polynucleotide in the microorganism.

[104] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: 3-mercaptopropionate dioxygenase (MDO; p3MDO) (EC 1.13.11.-); and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, p3MDO and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one or two, exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of p3MDO and GAD enzymes or enzyme activities is encoded an exogenous polynucleotide in the microorganism and the remaining activity is endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from an exogenous polynucleotide. In one embodiment, the microorganism expresses an endogenous GAD activity and p3MDO is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous p3MDO activity and GAD is encoded by an exogenous polynucleotide in the microorganism.

[105] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes p3MDO comprising or consisting of the amino acid sequence depicted in SEQ ID NO:33, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:33. In some embodiments, the polynucleotide that encodes p3MDO comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:34 or SEQ ID NO:60 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:34 or SEQ ID NO:60. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:60.

[106] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g. SEQ ID NO: 53 or SEQ ID NO:54.

[107] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[108] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding p3MDO and CSAD. In another embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding p3MDO and GAD.

[109] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes an exogenous polynucleotide encoding p3MDO. In one

embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding p3MDO and CSAD.

[110] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes an exogenous polynucleotide encoding p3MDO. In one

embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding p3MDO and CSAD.

[Ill] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes an exogenous polynucleotide encoding p3MDO. In one embodiment, a non- naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding p3MDO and CSAD.

Conversion of serine to taurine

[112] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies of the serine/sulfate pathway for biosynthesis of taurine. The serine/sulfate pathway for taurine biosynthesis is shown schematically in Fig. 4.

[113] In some embodiments, the non-naturally occurring microorganism includes one or more mutations that cause accumulation of serine in the microorganism. For example, a methylotrophic strain that uses ribulose monophosphate (RuMP) for carbon assimilation from methanol may include a deletion or mutation in HprA (hydroxypyruvate reductase), which blocks the serine cycle from being completed, resulting in serine accumulation.

[114] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: L-serine dehydratase (EC 4.3.1.17); sulfate adenyltransferase (EC 2.7.7.4) and adenylyl-sulfate kinase (APS kinase) (EC 2.7.1.25), and/or 3'- phosphoadenosine 5'-phosphosulfate synthase (PAPSS1) (EC 2.7.7.4/EC 2.7.1.25); 3'- phosphoadenylyl sulfate: 2-aminoacrylate C-sulfotransferase (PAPS-AS) (EC 2.8.2.-); and cysteine sulfinic acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, L-serine dehydratase; sulfate adenyltransferase and APS kinase, and/or PAPSS 1; PAPS-AS; and CSAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, four, five, six, or seven exogenous polynucleotide(s)) in the microorganism. In some embodiments, one, two, three, four, five, or six of L-serine dehydratase, sulfate

adenyltrasnferase, APS kinase, PAPSS1, PAPS-AS, and CSAD enzymes or enzyme activities is encoded by one or more exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses an endogenous L- serine dehydratase activity, and sulfate adenyltransferase and APS kinase, and/or PAPSS 1, PAPS-AS, and CSAD are expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous L-serine dehydratase, sulfate adenyltransferase, and APS kinase activity, and PAPS-AS and CSAD are expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous L-serine dehydratase, sulfate adenyltransferase, APS kinase, and CSAD activities, and PAPS-AS is expressed from an exogenous polynucleotide.

[115] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: L-serine dehydratase (EC 4.3.1.17); sulfate adenyltransferase (EC 2.7.7.4) and adenylyl-sulfate kinase (APS kinase) (EC 2.7.1.25), and/or 3'- phosphoadenosine 5'-phosphosulfate synthase (PAPSS1) (EC 2.7.7.4/EC 2.7.1.25); 3'- phosphoadenylyl sulfate: 2-aminoacrylate C-sulfotransferase (PAPS-AS) (EC 2.8.2.-); and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the

microorganism has been transformed. In some embodiments, L-serine dehydratase; sulfate adenyltrasnferase and APS kinase, and/or PAPSS1 ; PAPS-AS; and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, four, five, six, or seven exogenous polynucleotide(s)) in the microorganism. In some embodiments, one, two, three, four, five, or six of L-serine dehydratase, sulfate

adenyltransferase, APS kinase, PAPSS1, PAPS-AS, and GAD enzymes or enzyme activities is encoded by one or more exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses an endogenous L- serine dehydratase activity, and sulfate adenyltransferase and APS kinase, and/or PAPSS 1, PAPS-AS, and GAD are expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous L-serine dehydratase, sulfate adenyltransferase, APS kinase activity, and PAPS-AS and GAD are expressed from exogenous

polynucleotide(s). In one embodiment, the microorganism expresses endogenous L-serine dehydratase, sulfate adenyltransferase, APS kinase, and GAD activities, and PAPS-AS is expressed from an exogenous polynucleotide.

[116] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes L-serine dehydratase comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 1, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: l. In some embodiments, the polynucleotide that encodes L-serine dehydratase comprises or consists of the

polynucleotide sequence depicted in SEQ ID NO: 2 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:2. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[117] In some embodiments, the non-naturally occurring microorganism includes exogenous polynucleotides that encode sulfate adenyltransferase comprising or consisting of the amino acid sequences depicted in SEQ ID NO:3 and SEQ ID NO:5, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotides encode polypeptides comprising or consisting of amino acid sequences having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:3 or SEQ ID NO: 5. In some embodiments, the polynucleotides that encode sulfate adenyltransferase comprise or consists of the polynucleotide sequences depicted in SEQ ID NO:4 and SEQ ID NO:6 or polynucleotides having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:4 or SEQ ID NO:6. In some embodiments, the polynucleotide sequences are codon optimized for expression in the microorganism.

[118] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes APS kinase comprising or consisting of the amino acid sequence depicted in SEQ ID N0:7, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:7. In some embodiments, the polynucleotide that encodes APS kinase comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:8 or SEQ ID NO:62 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:8 or SEQ ID NO:62. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. SEQ ID NO:62.

[119] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes PAPSS1 comprising or consisting of the amino acid sequence depicted in SEQ ID NO:31, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:31. In some embodiments, the polynucleotide that encodes PAPSS1 comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:32 or SEQ ID NO:63 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:32 or SEQ ID NO:63. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:63.

[120] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes PAPS-AS comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 9, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:9. In some embodiments, the polynucleotide that encodes PAPS-AS comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 10 or SEQ ID NO:61 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 10 or SEQ ID NO:61. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:61. [121] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:53 or SEQ ID NO:54.

[122] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[123] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding: sulfate adenyltransferase and APS kinase, and/or PAPSS1 ; PAPS-AS; and CSAD. In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPS-AS and CSAD. In another embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding: sulfate adenyltransferase and APS kinase, and/or PAPSS1 ; PAPS-AS; and GAD. In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPS-AS and GAD.

[124] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes an exogenous polynucleotide encoding PAPS-AS. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1 and PAPS-AS. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1, PAPS-AS, and CSAD.

[125] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes an exogenous polynucleotide encoding PAPS-AS. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1 and PAPS-AS. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1, PAPS-AS, and CSAD.

[126] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes an exogenous polynucleotide encoding PAPS-AS. In one embodiment, a non- naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS 1 and PAPS-AS. In one embodiment, a non- naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1, PAPS-AS, and CSAD.

Conversion of phosphoserine or serine to taurine

[127] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of phosphoserine to taurine via the enzyme cysteate synthase, for example, enzyme(s) of the cysteate synthase (e.g., MA_3297)/CSAD or GAD pathway for biosynthesis of taurine, and/or expresses one or more exogenous enzyme activity/ies for the conversion of serine to taurine via the enzymes L-serine dehydratase, cysteate synthase (e.g. , MA_3297), and CS AD/GAD. The cysteate synthase (e.g., MA_3297)/CSAD or GAD, and L-serine dehydratase cysteate synthase (e.g., MA_3297)/CSAD or GAD pathways for taurine biosynthesis are shown schematically in Fig. 5. [128] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cysteate synthase, e.g. , MA_3297 (EC 2.5.1.76); optionally L-serine dehydratase (EC 4.3.1.17); and cysteine sulfinic acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, cysteate synthase, optionally L-serine dehydratase, and CSAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, or three, exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of cysteate synthase, L-serine dehydratase, or CSAD enzymes or enzyme activities is encoded by an exogenous polynucleotide in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e., not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous CSAD and optionally L-serine dehydratase activity, and cysteate synthase (e.g., MA_3297) is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous cysteate synthase and CSAD is encoded by an exogenous polynucleotide in the microorganism.

[129] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cysteate synthase, e.g. , MA_3297 (EC 2.5.1.76); optionally L-serine dehydratase (EC 4.3.1.17); and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some

embodiments, cysteate synthase, optionally L-serine dehydratase, and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, or three, exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of cysteate synthase, L-serine dehydratase, or GAD enzymes or enzyme activities is encoded by an exogenous polynucleotide in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e., not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous GAD and optionally L-serine dehydratase activity and cysteate synthase (e.g., MA_3297) is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous cysteate synthase and GAD is encoded by an exogenous polynucleotide in the microorganism.

[130] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes cysteate synthase comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 17, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 17. In some embodiments, the polynucleotide that encodes cysteate synthase comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 18, SEQ ID NO:52, or SEQ ID NO:64 or a

polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 18, SEQ ID NO:52, or SEQ ID NO:64. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:52 or SEQ ID NO:64.

[131] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes L-serine dehydratase comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 1, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: l. In some embodiments, the polynucleotide that encodes L-serine dehydratase comprises or consists of the

polynucleotide sequence depicted in SEQ ID NO: 2 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:2. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[132] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:53 or SEQ ID NO:54.

[133] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[134] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g. , MA_3297) and CSAD. In another embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g. , MA_3297) and GAD.

[135] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g., MA_3297) and optionally L-serine dehydratase. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g. , MA_3297), optionally L-serine dehydratase, and CSAD.

[136] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g., MA_3297) and optionally L-serine dehydratase. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g. , MA_3297), optionally L-serine dehydratase, and CSAD.

[137] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g. , MA 3297) and optionally L-serine dehydratase. In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g. , MA_3297), optionally L-serine dehydratase, and CSAD.

Conversion of cysteine to taurine, via CGL/CD; PAPS-AS. and CSAD or GAD

[138] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of cysteine to taurine via the enzymes cystathionine gamma-lyase (CGL)/ L-cysteine desulfhydrase (CD), 3'phosphoadenylyl sulfate: 2-aminoacry late C-sulfotransferase (PAPS-AS), and cysteine sulfinic acid decarboxylase (CSAD) or glutamate decarboxylase (GAD). This pathway for taurine biosynthesis is shown schematically in Fig. 6. Several proteins have been found to have L-cysteine desulfhydrase (CD) activity (EC 4.4.1.1) including cystathionine gamma- lyase (CGL), tryptophanase, cysteine synthases, and MalY (Awano et al. (2005) Appl Environ Microbiol 71(7):4149-52.). In some embodiments, a single enzyme includes both CGL and CD activities. In other embodiments, CGL and CD activities are provided by two separate enzymes. In some embodiments, CD activity is provided by an enzyme and CGL activity is absent. When CGL activity is present, it may provide greater flux via production of L-cysteine, which serves as a substrate for CD activity. In some embodiments, a first enzyme that includes both CGL and CD activities and a second enzyme that includes only CD activity are provided.

[139] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cystathionine gamma-lyase (CGL)/L-cysteine desulfhydrase (CD) (EC 4.4.1.1); sulfate adenyltransferase (EC 2.7.7.4) and adenylyl-sulfate kinase (APS kinase) (EC 2.7.1.25), and/or 3'-phosphoadenosine 5'-phosphosulfate synthase (PAPSS1) (EC 2.7.7.4/EC 2.7.1.25); 3'- phosphoadenylyl sulfate: 2-aminoacrylate C-sulfotransferase (PAPS-AS) (EC 2.8.2.-); and cysteine sulfinic acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, CGL/CD; sulfate adenyltransferase and APS kinase, and/or PAPSS l; PAPS- AS; and CSAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, four, five, six, or seven exogenous

polynucleotide(s)) in the microorganism. In some embodiments, one, two, three, four, five, or six of CGL/CD, sulfate adenyltransferase, APS kinase, PAPSSl, PAPS-AS, and CSAD enzymes or enzyme activities is encoded by one or more exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses an endogenous activity, and sulfate adenyltransferase and APS kinase and/or PAPSSl, PAPS- AS, and CSAD are expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous CGL/CD and sulfate adenyltransferase, APS kinase activities, and PAPS-AS and CSAD activities are expressed from exogenous

polynucleotide(s). In one embodiment, the microorganism expresses endogenous CGL/CD, sulfate adenyltransferase, APS kinase, and CSAD activities, and PAPS-AS is expressed from an exogenous polynucleotide.

[140] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cystathionine gamma-lyase (CGL)/ L-cysteine desulfhydrase (CD) (EC 4.4.1.1); sulfate adenyltransferase (EC 2.7.7.4) and adenylyl-sulfate kinase (APS kinase) (EC 2.7.1.25), and/or 3'-phosphoadenosine 5'-phosphosulfate synthase (PAPSSl) (EC 2.7.7.4/EC 2.7.1.25); 3'- phosphoadenylyl sulfate: 2-aminoacrylate C-sulfotransferase (PAPS-AS) (EC 2.8.2.-); and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, CGL/CD, sulfate adenyltransferase and APS kinase, and/or PAPSS l, PAPS-AS, and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, four, five, six, or seven exogenous polynucleotide(s)) in the microorganism. In some embodiments, one, two, three, four, five, or six of CGL/CD, sulfate adenyltransferase, APS kinase, PAPSSl, PAPS-AS, and GAD enzymes or enzyme activities is encoded by one or more exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e., not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses an endogenous activity, and sulfate

adenyltransferase and APS kinase, and/or PAPSS1, PAPS-AS, and GAD are expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous CGL/CD, sulfate adenyltransferase, and APS kinase activities, and PAPS-AS and GAD activities are expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous CGL/CD, sulfate adenyltransferase, APS kinase, and GAD activities, and PAPS-AS is expressed from an exogenous polynucleotide.

[141] In some embodiments, the non-naturally occurring microorganism includes one or more exogenous polynucleotide(s) that encode(s) CGL/CD comprising or consisting of the amino acid sequence(s) depicted in SEQ ID NO:46, SEQ ID NO:70, and/or SEQ ID NO:72 or variant(s) or homolog(s) thereof. In some embodiments, the exogenous polynucleotide(s) encode(s) polypeptide(s) comprising or consisting of amino acid sequence(s) having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:46, SEQ ID NO:70, and/or SEQ ID NO:72. In some embodiments, the

polynucleotide(s) that encode(s) CGL/CD comprise or consist of the polynucleotide sequence(s) depicted in SEQ ID NO:47, SEQ ID NO:65, SEQ ID NO:71 and/or SEQ ID NO:73, or polynucleotide(s) having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:47, SEQ ID NO:65, SEQ ID NO:71, and/or SEQ ID NO:73. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:65.

[142] In some embodiments, the non-naturally occurring microorganism includes exogenous polynucleotides that encode sulfate adenyltransferase comprising or consisting of the amino acid sequences depicted in SEQ ID NO:3 and SEQ ID NO:5, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotides encode polypeptides comprising or consisting of an amino acid sequences having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:3 or SEQ ID NO:5. In some embodiments, the polynucleotides that encode sulfate

adenyltransferase comprises or consists of the polynucleotide sequences depicted in SEQ ID NO:4 or SEQ ID NO:6 or polynucleotides having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:4 or SEQ ID NO:6. In some embodiments, the polynucleotide sequences are codon optimized for expression in the microorganism. [143] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes APS kinase comprising or consisting of the amino acid sequence depicted in SEQ ID NO:7, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:7. In some embodiments, the polynucleotide that encodes APS kinase comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:8 or SEQ ID NO:62 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:8 or SEQ ID NO:62. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:62.

[144] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes PAPSS1 comprising or consisting of the amino acid sequence depicted in SEQ ID NO:31, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:31. In some embodiments, the polynucleotide that encodes PAPSS1 comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:32 or SEQ ID NO:63 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:32 or SEQ ID NO:63. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:63.

[145] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes PAPS-AS comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 9, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:9. In some embodiments, the polynucleotide that encodes PAPS-AS comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 10 or SEQ ID NO:61 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 10 or SEQ ID NO:61. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:61.

[146] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:53 or SEQ ID NO:54.

[147] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[148] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding: CGL/CD, sulfate adenyltransferase and APS kinase, and/or PAPSS1 ; PAPS-AS, and CSAD. In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CGL/CD, PAPS-AS and CSAD. In another embodiment, a non-naturally occurring Methylobacterium

microorganism is provided that includes one or more exogenous polynucleotide(s) encoding: CGL/CD; sulfate adenyltransferase and APS kinase, and/or PAPSS 1, PAPS-AS, and GAD. In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CGL/CD, PAPS-AS and GAD.

[149] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes an exogenous polynucleotide encoding PAPS-AS. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1 and PAPS-AS. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1, PAPS-AS, and CSAD.

[150] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes an exogenous polynucleotide encoding PAPS-AS. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1 and PAPS-AS. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1, PAPS-AS, and CSAD.

[151] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes an exogenous polynucleotide encoding PAPS-AS. In one embodiment, a non- naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS 1 and PAPS-AS. In one embodiment, a non- naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding PAPSS1, PAPS-AS, and CSAD.

Conversion of cysteine to taurine via CGL/CD and cvsteate synthase

[152] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of cysteine to taurine via the enzymes cystathionine gamma-lyase/ L-cysteine desulfhydrase, cysteate synthase (e.g. , MA_3297), and cysteine sulfinic acid decarboxylase (CSAD) or glutamate decarboxylase (GAD). The CGL/CD, cysteate synthase (e.g., MA_3297), CSAD or GAD pathway for taurine biosynthesis is shown schematically in Fig. 7. Several proteins have been found to have L-cysteine desulfhydrase (CD) activity (EC 4.4.1.1) including cystathionine gamma-lyase (CGL), tryptophanase, cysteine synthases, and MalY (Awano et al. (2005) Appl Environ Microbiol 71(7):4149-52.). In some embodiments, a single enzyme includes both CGL and CD activities. In other embodiments, CGL and CD activities are provided by two separate enzymes. In some embodiments, CD activity is provided by an enzyme and CGL activity is absent. When CGL activity is present, it may provide greater flux via production of L-cysteine, which serves as a substrate for CD activity. In some embodiments, a first enzyme that includes both CGL and CD activities and a second enzyme that includes only CD activity are provided.

[153] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cystathionine gamma-lyase (CGL)/ L-cysteine desulfhydrase (CD) (EC4.4.4.1), cysteate synthase, e.g. , MA_3297 (EC 2.5.1.76); and cysteine sulfuric acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the

microorganism has been transformed. In some embodiments, CGL/CD, cysteate synthase, and CSAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, or four exogenous polynucleotide(s)) in the microorganism. In some embodiments, one or more of CGL/CD, cysteate synthase, and CSAD enzymes or enzyme activities is encoded by one or more exogenous

polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from exogenous polynucleotide(s). In one embodiment, the

microorganism expresses an endogenous CSAD activity and CGL/CD and cysteate synthase (e.g., MA_3297) are encoded by exogenous polynucleotide(s) in the

microorganism. In one embodiment, the microorganism expresses endogenous CGL/CD and CSAD activities and cysteate synthase (e.g., MA_3297) is encoded by an exogenous polynucleotide in the microorganism.

[154] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: cystathionine gamma-lyase (CGL)/ L-cysteine desulfhydrase (CD) (EC4.4.4.1), cysteate synthase, e.g. , MA_3297 (EC 2.5.1.76); and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, CGL/CD, cysteate synthase, and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, or four exogenous polynucleotide(s)) in the microorganism. In some embodiments, one or more of CGL/CD, cysteate synthase, and GAD enzymes or enzyme activities is encoded by one or more exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses an endogenous GAD activity and CGL/CD and cysteate synthase (e.g., MA_3297) are encoded by exogenous polynucleotide(s) in the microorganism. In one embodiment, the microorganism expresses endogenous CGL/CD and GAD activities and cysteate synthase (e.g., MA_3297) is encoded by an exogenous polynucleotide in the microorganism.

[155] In some embodiments, the non-naturally occurring microorganism includes one or more exogenous polynucleotide(s) that encode(s) CGL/CD comprising or consisting of the amino acid sequence(s) depicted in SEQ ID NO:46, SEQ ID NO:70, and/or SEQ ID NO:72 or variant(s) or homolog(s) thereof. In some embodiments, the exogenous

polynucleotide(s) encode(s) polypeptide(s) comprising or consisting of amino acid sequence(s) having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:46, SEQ ID NO:70, and/or SEQ ID NO:72. In some embodiments, the polynucleotide(s) that encode(s) CGL/CD comprise or consist of the polynucleotide sequence(s) depicted in SEQ ID NO:47, SEQ ID NO:65, SEQ ID NO:71, and/or SEQ ID NO:73 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:47, SEQ ID NO:65, SEQ ID NO:71, and/or SEQ ID NO:73. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO: 65.

[156] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes cysteate synthase comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 17, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 17. In some embodiments, the polynucleotide that encodes cysteate synthase comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 18, SEQ ID NO:52, or SEQ ID NO:64 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 18, SEQ ID NO:52, or SEQ ID NO:64. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:52 or SEQ ID NO:64.

[157] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:53 or SEQ ID NO:54.

[158] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[159] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CGL/CD, cysteate synthase (e.g., MA_3297), and CSAD. In another embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CGL/CD, cysteate synthase (e.g., MA_3297), and GAD.

[160] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CGL/CD and cysteate synthase (e.g., MA_3297). In one embodiment, a non-naturally occurring

Escherichia microorganism is provided that includes one or more exogenous

polynucleotide(s) encoding CGL/CD, cysteate synthase, and CSAD.

[161] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CGL/CD and cysteate synthase (e.g., MA_3297). In one embodiment, a non-naturally occurring

Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding CGL/CD, cysteate synthase, and CSAD.

[162] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cysteate synthase (e.g., MA_3297) and CSAD.

Conversion of pyruvate to taurine

[163] In some embodiments, a non-naturally occurring microorganism is provided that expresses exogenous enzyme activity/ies for the conversion of pyruvate to taurine via the enzyme L-cysteate sulfo-lyase (cuyA), for example, exogenous enzyme(s) of the L-cysteate sulfo-lyase (cuyA)/CSAD or GAD pathway for biosynthesis of taurine. The cuyA/CSAD or GAD pathway for taurine biosynthesis is shown schematically in Fig. 8.

[164] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: L-cysteate sulfo-lyase (cuyA) (EC 4.4.1.25); and cysteine sulfinic acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the

microorganism has been transformed. In some embodiments, cuyA and CSAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one or two exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of cuyA and CSAD enzymes or enzyme activities is encoded by an exogenous polynucleotide in the microorganism and the remaining activity is endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e., not expressed from an exogenous polynucleotide. In one embodiment, the microorganism expresses an endogenous CSAD activity and cuyA is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous cuyA activity and CSAD is encoded by an exogenous polynucleotide in the microorganism.

[165] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: L-cysteate sulfo-lyase (cuyA) (EC 4.4.1.25); and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, cuyA and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one or two exogenous polynucleotide(s)) in the microorganism. In some embodiments, one of cuyA and GAD enzymes or enzyme activities is encoded by an exogenous polynucleotide in the

microorganism and the remaining activity is endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from an exogenous polynucleotide. In one embodiment, the microorganism expresses an endogenous GAD activity and cuyA is encoded by an exogenous polynucleotide in the microorganism. In one embodiment, the microorganism expresses an endogenous cuyA activity and GAD is encoded by an exogenous polynucleotide in the microorganism.

[166] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes cuyA comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 37, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:37. In some embodiments, the polynucleotide that encodes cuyA comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:38 or SEQ ID NO:66 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:38 or SEQ ID NO:66. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:66.

[167] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:53 or SEQ ID NO:54.

[168] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[169] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cuyA and CSAD. In another embodiment, a non-naturally occurring Methylobacterium

microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cuyA and GAD.

[170] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes an exogenous polynucleotide encoding cuyA. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cuyA and CSAD.

[171] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes an exogenous polynucleotide encoding cuyA. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cuyA and CSAD. [172] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes an exogenous polynucleotide encoding cuyA. In one embodiment, a non- naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding cuyA and CSAD.

Conversion of phosphoenolpyruvate to taurine via CSAD or GAD

[173] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of

phosphoenolpyruvate to taurine via the enzymes phosphosulfolactate synthase (ComA), 2- phsopho-e-sulfolactate dehydrogenase (ComB), sulfolactate dehydrogenase (ComC), and aspartate aminotransferase (AspAT), for example, one or more exogenous enzyme(s) of the ComA/ComB/ComC/AspAT/CSAD or GAD pathway for biosynthesis of taurine. The ComA/ComB/ComC/AspAT/CSAD or GAD pathway for taurine biosynthesis is shown schematically in Fig. 9.

[174] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: phosphosulfolactate synthase (ComA) (EC 4.4.1.19), 2- phospho-3 -sulfolactate phosphohydrolase (ComB) (EC 3.1.3.71), sulfolactate

dehydrogenase (ComC) (EC 1.1.1.337), aspartate aminotransferase (AspAT) (EC 2.6.1.1), and cysteine sulfinic acid decarboxylase (CSAD) (EC 4.1.1.29), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, ComA, ComB, ComC, AspAT, and CSAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, four, or five exogenous polynucleotide(s)) in the microorganism. In some embodiments, one or more of ComA, ComB, ComC, AspAT, and CSAD enzymes or enzyme activities is encoded by one or more exogenous

polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from exogenous polynucleotide(s). In one embodiment, the

microorganism expresses endogenous CSAD and AspAT activities, and ComA, ComB, and ComC are encoded by exogenous polynucleotide(s) in the microorganism. In one embodiment, the microorganism expresses endogenous AspAT activity, and ComA, ComB, ComC, and CSAD are encoded by exogenous polynucleotide(s) in the microorganism. [175] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: phosphosulfolactate synthase (ComA) (EC 4.4.1.19), 2- phospho-3-sulfolactate phosphohydrolase (ComB) (EC 3.1.3.71), sulfolactate

dehydrogenase (ComC) (EC 1.1.1.337), aspartate aminotransferase (AspAT) (EC 2.6.1.1), and glutamate decarboxylase (GAD) (EC 4.1.1.15), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the

microorganism has been transformed. In some embodiments, ComA, ComB, ComC, AspAT, and GAD enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, four, or five exogenous polynucleotide(s)) in the microorganism. In some embodiments, one or more of ComA, ComB, ComC, AspAT, and GAD enzymes or enzyme activities is encoded by one or more exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from exogenous polynucleotide(s). In one embodiment, the microorganism expresses endogenous GAD and AsPAT activities, and ComA, ComB, and ComC are encoded by exogenous polynucleotide(s) in the microorganism. In one embodiment, the microorganism expresses endogenous AsPAT activity, and ComA, ComB, ComC, and GAD are encoded by exogenous polynucleotide(s) in the microorganism.

[176] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComA comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 19, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 19. In some embodiments, the polynucleotide that encodes ComA comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:20 or SEQ ID NO:67 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:20 or SEQ ID NO:67. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:67.

[177] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComB comprising or consisting of the amino acid sequence depicted in SEQ ID NO:21, or a variant or homolog thereof. In some embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:21. In some embodiments, the polynucleotide that encodes ComB comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:22 or SEQ ID NO:68 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:22 or SEQ ID NO:68. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:68.

[178] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComC comprising or consisting of the amino acid sequence depicted in SEQ ID NO:23, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:23. In some embodiments, the polynucleotide that encodes ComC comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:24 or SEQ ID NO:69 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:24 or SEQ ID NO:69. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. SEQ ID NO:69.

[179] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes CSAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 11, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 11. In some embodiments, the polynucleotide that encodes CSAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 12, SEQ ID NO:53, or SEQ ID NO:54. In some embodiments, the

polynucleotide sequence is codon optimized for expression in the microorganism, e.g., SEQ ID NO:53 or SEQ ID NO:54. [180] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes GAD comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 13, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 13. In some embodiments, the polynucleotide that encodes GAD comprises or consists of the polynucleotide sequence depicted in SEQ ID NO: 14 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 14. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[181] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, and CSAD. In another embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, and GAD.

[182] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, and ComC. In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, and CSAD.

[183] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, and ComC. In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, and CSAD.

[184] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, and ComC. In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, and CSAD. Conversion of acetyl phosphate to taurine

[185] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of acetyl phosphate to taurine, for example, enzymes of the Xsc/Tpa pathway for biosynthesis of taurine. The Xsc/Tpa pathway of taurine biosynthesis is shown schematically in Fig. 10.

[186] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: sulfoacetaldehyde acetyltransferase (Xsc) (EC 2.3.3.15); and taurine-pyruvate aminotransferase (Tpa) (EC 2.6.1.77), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, Xsc and Tpa enzymes or enzyme activities are encoded by one or more exogenous polynucleotides in the

microorganism (e.g., one or two exogenous polynucleotide(s). In some embodiments, one of Xsc and Tpa enzymes or enzyme activities is encoded an exogenous polynucleotide in the microorganism and the remaining activity is endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e. , not expressed from an exogenous polynucleotide.

[187] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes Xsc comprising or consisting of the amino acid sequence depicted in SEQ ID NO:48, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:48. In some embodiments, the polynucleotide that encodes Xsc comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:49 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:49. In some

embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism.

[188] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes Tpa comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 27, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:27. In some embodiments, the polynucleotide that encodes Tpa comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:28 or SEQ ID NO:56 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:28 or SEQ ID NO:56. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:56.

[189] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding Xsc and Tpa.

[190] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes an exogenous polynucleotide encoding Xsc and Tpa.

[191] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes an exogenous polynucleotide encoding Xsc and Tpa.

[192] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes an exogenous polynucleotide encoding Xsc and Tpa.

Conversion of phosphoenolpyruvate to taurine via Tpa

[193] In some embodiments, a non-naturally occurring microorganism is provided that expresses one or more exogenous enzyme activity/ies for the conversion of

phosphoenolpyruvate to taurine via the enzymes phosphosulfolactate synthase (ComA), 2- phsopho-e-sulfolactate dehydrogenase (ComB), sulfolactate dehydrogenase (ComC), sulfopyruvate decarboxylase (ComDE), and taurine-pyruvate aminotransferase (Tpa), for example, one or more exogenous enzyme(s) of the ComA/ComB/ComC, ComDE/Tpa pathway for biosynthesis of taurine. This pathway for taurine biosynthesis is shown schematically in Fig. 11.

[194] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: phosphosulfolactate synthase (ComA) (EC 4.4.1.19), 2- phospho-3 -sulfolactate phosphohydrolase (ComB) (EC 3.1.3.71), sulfolactate

dehydrogenase (ComC) (EC 1.1.1.337), sulfopyruvate decarboxylase (ComDE) (EC 4.1.7.9), and taurine-pyruvate aminotransferase (Tpa) (EC 2.6.1.77), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed. In some embodiments, ComA, ComB, ComC, ComDE, and Tpa enzymes or enzyme activities are encoded by one or more exogenous polynucleotide(s) (e.g., one, two, three, four, or five exogenous polynucleotide(s)) in the microorganism. In some embodiments, one or more of ComA, ComB, ComC, ComDE, and Tpa enzymes or enzyme activities is encoded by one or more exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non-naturally occurring microorganism is derived, i.e., not expressed from exogenous polynucleotide(s).

[195] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComA comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 19, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO: 19. In some embodiments, the polynucleotide that encodes ComA comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:20 or SEQ ID NO:67 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:20 or SEQ ID NO:67. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:67.

[196] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComB comprising or consisting of the amino acid sequence depicted in SEQ ID NO:21, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:21. In some embodiments, the polynucleotide that encodes ComB comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:22 or SEQ ID NO:68 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:22 or SEQ ID NO:68. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:68.

[197] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComC comprising or consisting of the amino acid sequence depicted in SEQ ID NO:23, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:23. In some embodiments, the polynucleotide that encodes ComC comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:24 or SEQ ID NO:69 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:24 or SEQ ID NO:69. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:69.

[198] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComDE comprising or consisting of the amino acid sequence depicted in SEQ ID NO:25, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:25. In some embodiments, the polynucleotide that encodes ComDE comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:26 or SEQ ID NO:55 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:26 or SEQ ID NO:55. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:55.

[199] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes Tpa comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 27, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:27. In some embodiments, the polynucleotide that encodes Tpa comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:28 or SEQ ID NO:56 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:28 or SEQ ID NO:56. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:56.

[200] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, and ComDE, and Tpa. [201] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, ComDE, and Tpa.

[202] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, ComDE, and Tpa.

[203] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComA, ComB, ComC, ComDE, and Tpa.

Conversion of cvsteate to taurine via AspAT. ComDE. and Tpa

[204] Cysteate, which is an intermediate in some of the biosynthetic pathways described above (see Figs. 4, 5, 6, 7, and 8) be converted to taurine via aspartate aminotransferase (AspAT) (EC 2.6.1.1), which converts cysteate to sulfopyruvate, sulfopyruvate

decarboxylase (ComDE) (EC4.1.7.9), which converts sulfopyruvate to sulfoacetaldehyde, and taurine-pyruvate aminotransferase (Tpa) (EC 2.67.1.77), which converts

sulfoacetaldehyde to taurine, instead of or in addition to CSAD or GAD. This is shown schematically in Fig. 12.

[205] Non-naturally occurring microorganisms are provided that include the following enzymes or enzyme activities: aspartate aminotransferase (AspAT) (EC 2.6.1.1);

sulfopyruvate decarboxylase (ComDE) (EC4.1.7.9); and taurine-pyruvate aminotransferase (Tpa) (EC 2.67.1.77), wherein at least one of these enzymes or enzyme activities is encoded by an exogenous polynucleotide with which the microorganism has been transformed, and optionally other enzyme activities for production of cysteate, as shown in Fig. 12, either endogenous to the microorganism or encoded by exogenous polynucleotide(s) with which the microorganism has been transformed.

[206] In some embodiments, one or more of AspAT, ComDE, and Tpa enzymes or enzyme activities is encoded by exogenous polynucleotide(s) in the microorganism and the remaining activity/ies is/are endogenously expressed in the host cell from which the non- naturally occurring microorganism is derived, i.e., not expressed from an exogenous polynucleotide. In one embodiment, the microorganism expresses an endogenous AspAT activity and ComDE and Tpa are encoded by exogenous polynucleotide(s) in the microorganism. [207] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes ComDE comprising or consisting of the amino acid sequence depicted in SEQ ID NO:25, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:25. In some embodiments, the polynucleotide that encodes ComDE comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:26 or SEQ ID NO:55 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:26 or SEQ ID NO:55. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:55.

[208] In some embodiments, the non-naturally occurring microorganism includes an exogenous polynucleotide that encodes Tpa comprising or consisting of the amino acid sequence depicted in SEQ ID NO: 27, or a variant or homolog thereof. In some

embodiments, the exogenous polynucleotide encodes a polypeptide comprising or consisting of an amino acid sequence having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:27. In some embodiments, the polynucleotide that encodes Tpa comprises or consists of the polynucleotide sequence depicted in SEQ ID NO:28 or SEQ ID NO:56 or a polynucleotide having at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98, or 99% identity to SEQ ID NO:28 or SEQ ID NO:56. In some embodiments, the polynucleotide sequence is codon optimized for expression in the microorganism, e.g. , SEQ ID NO:56.

[209] In one embodiment, a non-naturally occurring Methylobacterium microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComDE and Tpa.

[210] In one embodiment, a non-naturally occurring Escherichia microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComDE and Tpa.

[211] In one embodiment, a non-naturally occurring Saccharomyces microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComDE and Tpa.

[212] In one embodiment, a non-naturally occurring Bacillus microorganism is provided that includes one or more exogenous polynucleotide(s) encoding ComDE and Tpa. Mutations to enhance accumulation of taurine or an intermediate in taurine biosynthesis

[213] In some embodiments, a non-naturally occurring microorganism is provided that produces taurine, as described above, and that further includes a mutation in a pathway for degradation of taurine and/or in a pathway for degradation of an intermediate of taurine biosynthesis (e.g., a cysteate degradation pathway). In some embodiments, the

microorganism includes deletion of one or more endogenous gene sequence that encodes an enzyme that degrades taurine or an intermediate in taurine biosynthesis (e.g. , cysteate or sulfoacetaldehyde), thus enhancing accumulation of taurine in the microorganism. Taurine and cysteate degradation pathways are shown schematically in Fig. 13. Examples of enzymes in taurine degradation pathways include, but are not limited to, taurine

dehydrogenase (TDH), taurine dioxygenase (TDO/TauD), gamma-glutamyltransferase, and taurine-pyruvate aminotransferase (Tpa). A non-limiting example of an enzyme in a cysteate degradation pathway is cysteate sulfo-lyase (CuyA). A non-limiting example of an enzyme in a sulfoacetaldehyde degradation pathway is sulfoacetaldehyde acetyltransferase (Xsc).

[214] In some embodiments, the non-naturally occurring microorganism includes one or more mutation(s) or deletion of a gene sequence that encodes taurine dehydrogenase (TDH) (EC 1.4.99.2), thus reducing or eliminating activity of TDH in the microorganism in comparison to the host cell from which the microorganism was derived.

[215] In some embodiments, the non-naturally occurring microorganism includes one or more mutation(s) or deletion of a gene sequence that encodes taurine dioxygenase

(TDO)/TauD (EC 1.14.11.17), thus reducing or eliminating activity of TDO/TauD in the microorganism in comparison the host cell from which the microorganism was derived. In one embodiment, an Escherichia microorganism is provided with one or more mutation(s) or deletion of a gene sequence that encodes TDO/TauD, thus reducing or eliminating activity of this enzyme in the microorganism. In one embodiment, a Saccharomyces microorganism is provided with one or more mutation(s) or deletion of a gene sequence that encodes TDO/TauD, thus reducing or eliminating activity of this enzyme in the

microorganism in comparison to the host cell from which the microorganism was derived. In one embodiment, a Bacillus microorganism is provided with one or more mutation(s) or deletion of a gene sequence that encodes TDO/TauD, thus reducing or eliminating activity of this enzyme in the microorganism in comparison to the host cell from which the microorganism was derived.

[216] In some embodiments, the non-naturally occurring microorganism includes one or more mutation(s) or deletion of a gene sequence that encodes cysteate sulfo-lyase (CuyA) (EC 4.4.1.25), thus reducing or eliminating activity of CuyA in the microorganism in comparison to the host cell from which the microorganism was derived.

[217] In some embodiments, the non-naturally occurring microorganism includes one or more mutation(s) or deletion of a gene sequence that encodes gamma-glutamyltransferase (EC 2.3.2.2), thus reducing or eliminating activity of gamma-glutamyltransferase in the microorganism in comparison the host cell from which the microorganism was derived. In one embodiment, aMethylobacterium microorganism is provided with one or more mutation(s) or deletion of a gene sequence that encodes gamma-glutamyltransferase, thus reducing or eliminating activity of this enzyme in the microorganism. In one embodiment, an Escherichia microorganism is provided with one or more mutation(s) or deletion of a gene sequence that encodes gamma-glutamyltransferase, thus reducing or eliminating activity of this enzyme in the microorganism in comparison to the host cell from which the microorganism was derived. In one embodiment, a Bacillus microorganism is provided with one or more mutation(s) or deletion of a gene sequence that encodes gamma- glutamyltransferase, thus reducing or eliminating activity of this enzyme in the

microorganism in comparison to the host cell from which the microorganism was derived.

[218] In some embodiments, the non-naturally occurring microorganism includes one or more mutations(s) or deletion of a gene sequence that encodes a taurine-pyruvate aminotransferase (Tpa) (EC 2.6.1.77), thus reducing or eliminating activity of taurine- pyruvate aminotransferase in the microorganism in comparison the host cell from which the microorganism was derived.

[219] In some embodiments, the non-naturally occurring microorganism includes one or more mutations(s) or deletion of a gene sequence that encodes a sulfoacetaldehyde acetyltransferase (Xsc) (EC 2.3.3.15), thus reducing or eliminating activity of

sulfoacetaldehyde acetyltransferase in the microorganism in comparison the host cell from which the microorganism was derived. Transformation of microorganisms

[220] Numerous transformation protocols and constructs for introducing and expressing exogenous polynucleotides in host cells are known in the art.

[221] In certain embodiments, genetic modifications will take advantage of freely replicating plasmid vectors for cloning. These may include small IncP vectors developed for use in Methylobacterium. These vectors may include pCM62, pCM66, or pHC41 for cloning. (Marx, C. J. and M. E. Lidstrom Microbiology (2001) 147: 2065-2075; Chou, H - H. et al. PLoS Genetics (2009) 5: el 000652)

[222] In certain embodiments, genetic modifications will take advantage of freely replicating expression plasmids such as pCM80, pCM160, pHC90, or pHC91. (Marx, C. J. and M. E. Lidstrom Microbiology (2001) 147: 2065-2075; Chou, H.-H. et al. PLoS Genetics (2009) 5: el 000652)

[223] In certain embodiments, genetic modifications will utilize freely replicating expression plasmids that have the ability to respond to levels of inducing molecules such as cumate or anhydrotetracycline. These include pHC115, pLC 290, pLC291. (Chou, H.-H. et al. PLoS Genetics (2009) 5: el000652; Chubiz, L. M. et al. BMC Research Notes (2013) 6: 183)

[224] In certain embodiments, genetic modifications will utilize recyclable antibiotic marker systems such as the cre-lox system. This may include use of the pCM157, pCM158, pCM184, pCM351 series of plasmids developed for use in extorquens. (Marx, C. J. and M. E. Lidstrom BioTechniques (2002) 33: 1062-1067)

[225] In certain embodiments, genetic modifications will utilize recyclable antibiotic marker systems such as the cre-lox system. This may include use of the pCM157, pCM158, pCM184, pCM351 series of plasmids developed for use in M. extorquens. (Marx, C. J. and M. E. Lidstrom BioTechniques (2002) 33: 1062-1067).

[226] In certain embodiments, genetic modifications will utilize transposon mutagenesis. This may include mini-Tn5 delivery systems such as pCM639 (D'Argenio, D. A. et al. Journal of Bacteriology (2001) 183: 1466-1471) demonstrated in M. extorquens. (Marx, C. J. et al. Journal of Bacteriology (2003) 185: 669-673)

[227] In certain embodiments, genetic modifications will utilize expression systems introduced directly into a chromosomal locus. This may include pCM168, pCM172, and pHCOl plasmids developed forM. extorquens. AMI . (Marx, C. J. and M. E. Lidstrom Microbiology (2001) 147: 2065-2075; Lee, M.-C. et al. Evolution (2009) 63: 2813-2830) [228] In certain embodiments, genetic modifications will utilize a sacB-based system for unmarked exchange of alleles due to the sucrose sensitivity provided by sacB expression. This may include the pCM433 vector originally tested with M. extorquens. (Marx, C. J. et al. BMC Research Notes (2008) 1 : 1)

Microbial cultures

[229] Methods for producing taurine and/or taurine precursors are provided. The methods include culturing a non-naturally occurring microorganism as described herein in a culture medium under conditions suitable for growth of the microorganism and expression of enzymes for taurine biosynthesis as described herein, wherein biomass that includes taurine and/or taurine precursors is produced in the culture. In embodiments in which the microorganism also produces one or more carotenoid compound(s) (e.g., a microorganism that has been genetically modified or artificially pre-selected to produce elevated levels of one or more carotenoid compound(s)), biomass that includes taurine and/or taurine precursors and the one or more carotenoid compound(s) is produced.

[230] The culture medium includes carbon source(s), nitrogen source(s), inorganic substances (e.g., inorganic salts), and any other substances required for the growth of the microorganism (e.g. , vitamins, amino acids, etc.).

[231] The carbon source may include sugars, such as glucose, sucrose, lactose, fructose, trehalose, mannose, mannitol, and maltose; organic acids, such as acetic acid, fumaric acid, citric acid, propionic acid, malic acid, pyruvic acid, malonic acid, and ascorbic acid;

alcohols, such as ethanol, propanol, butanol, pentanol, hexanol, isobutanol, and glycerol; oil or fat, such as soybean oil, rice bran oil, olive oil, corn oil, sesame oil, linseed oil, and the like. The amount of the carbon source added varies according to the kind of the carbon source, for example, about 1 to about 100 g, or about 2 to about 50 g per liter of medium.

[232] In some embodiments, a CI carbon substrate is provided to a microorganism that is capable of converting such a substrate to organic products (e.g. , microorganisms of the genera Methylobacterium, Methylomonas, Methylobacter. Methylococcus, Methylosinus, Methylocyctis, Methylomicrobium). In certain embodiments, the CI carbon substrate is selected from methane, methanol, formaldehyde, formic acid, methylated amines, methylated thiols, and carbon dioxide. In certain embodiments, the CI carbon substrate is selected from methanol, formaldehyde, and methylated amines. In certain embodiments, the CI carbon substrate is methanol.

[233] The nitrogen source may include potassium nitrate, ammonium nitrate, ammonium chloride, ammonium sulfate, ammonium phosphate, ammonia, urea, and the like, alone or in combination. Amount of the nitrogen source added varies according to the kind of the nitrogen source, for example, about 0.1 to about 30 g, or about 1 to about 10 g per liter of medium.

[234] Inorganic salts may include potassium dihydrogen phosphate, dipotassium hydrogen phosphate, disodium hydrogen phosphate, magnesium sulfate, magnesium chloride, ferric sulfate, ferrous sulfate, ferric chloride, ferrous chloride, manganous sulfate, manganous chloride, zinc sulfate, zinc, chloride, cupric sulfate, calcium chloride, calcium carbonate, sodium carbonate, sodium sulfate, and the like, alone or in combination. Amount of inorganic salt varies according to the kind of the inorganic salt, for example, about 0.001 to about 10 g per liter of medium.

[235] Special required substances, for example, vitamins, nucleic acids, yeast extract, peptone, meat extract, malt extract, corn steep liquor, soybean meal, dried yeast etc., may be included alone or in combination. Amount of the special required substance used varies according to the kind of the substance, for example, about 0.2 g to about 200 g, or about 3 to about 10 g per liter of medium.

[236] In some embodiments, the pH of the culture medium is adjusted to pH about 2 to about 12, or about 6 to about 9. The medium may further include one or more buffer(s) to maintain the culture at the desired pH. Numerous buffers are known in the art and include phosphate, carbonate, acetate, PIPES, HEPES, and Tris buffers. A suitable buffer for a given microorganism can easily be determined by one of ordinary skill in the art. For Methylobacterium, a common medium, described by Lee, et al. (2009) Evolution 63:2813- 2830, is a phosphate buffered medium that consists of 1 mL of trace metal solution (to 1 liter of deionized water the following are added in this order: 12.738 g of EDTA disodium salt dihydrate, 4.4 g of ZnSO -7H ₂ 0, 1 .466 g of CaCI ₂ -2H ₂ 0, 1 .012 g of MnCI ₂ -4H ₂ 0, 0.22 g of (ΝΗ4)6Μθ7θ ₂ 4-4Η ₂ 0, 0.314 g of CuSO ₄ -5H ₂ 0, 0.322 g of CoCl ₂ -6H ₂ 0, and 0.998 g of Fe3(SO ₄ ) ₂ -7H ₂ 0; pH 5.0 is maintained after every addition), 100 mL of phosphate buffer (25.3 g of K ₂ HPO ₄ and 22.5 g of NaH ₂ PO ₄ in 1 liter of deionized water), 100 mL of sulfate solution (5 g of (NH ₄ ) ₂ (SO ₄ ) and 0.98 g of Mg(SO ₄ ) ₂ in 1 liter of deionized water), and 799 mL of deionized water. All components are heat sterilized separately and then pooled together. An alternative medium recently developed for use with Methylobacterium extorquens takes advantage of an organic buffer and has a citrate-chelated trace metal mix. Culturing is carried out at temperature of 15° to 40°C, and preferably 20° to 35°C, usually for 1 to 20 days, and preferably 1 to 4 days, under aerobic conditions provided by shaking or aeration/agitation. Common practice with Methylobacterium is at 30°C. The protocol for making M-PIPES medium is described in Table S I of Delaney et al. (2013) PLoS One (8:e62957). Figure 2 in USSN 61/863,701 shows an exemplary recipe for medium optimized for use with extorquens.

[237] In order to generate dense cultures of microorganisms, such as Methylobacterium, it may be advantageous to use a fed-batch method. Methanol can be tolerated well at 0.5-1 % v/v (-120-240 mM), and thus this step size of addition can be used repeatedly. Critically, pH levels drop during culturing on methanol, such that the use of a base such as KOH or NaOH would be important to maintain the pH around 6.5. Aeration can be achieved via physical agitation, such as an impeller, via bubbling of filtered air or pure oxygen, or in combination. In order to reduce production costs, the buffer can be replaced from phosphates or PIPES to a carbonate-buffered medium.

[238] Microbial cells may be separated from the culture, for example, by a conventional means such as centrifugation or filtration. The cells may be isolated whole, or may be lysed to release their contents for extraction or further processing. The cells or the medium may be subjected to an extraction with a suitable solvent.

Intracellular taurine as a molecular chaperone and antioxidant.

[239] Microbial cells engineered to produce high levels of taurine or hypotaurine have increased levels of an important osmolyte known to promote protein folding and decrease oxidation (Warskulat et al. (2007) Methods Enzymol 428:439-58; Abe et al. (2015) Amino acids 47(5):909-15; Fujii et al. (2007) J Biochem 141(5):697-707); Oliveira et al. (2010) Pharmacological Reports 62: 185-193; Aruoma et al. (1988) Biochem J 256:251-55; Bucolo et al. (2016) Acta Ophthalmologic 95(256); Patel et al. (2016) Exp Toxic Pathol 68(2- 3): 103-12; Fontana et al. (2004) Neurochemical Research 29(1): 111-116). When microbial cells are used to express a protein of interest, intracellular taurine or hypotaurine could aid in increasing protein folding or decreasing protein inactivation through oxidation. Thus the use of microorganisms engineered to accumulate intracellular taurine or hypotaurine could be used to increase the yield and/or specific activity of proteins of interest.

[240] Production of intracellular taurine and/or hypotaurine to aid in protein folding has potential benefits, both for cost and effectiveness. In vivo production of taurine or hypotaurine should be less expensive than when taurine or hypotaurine are added externally. Intracellular protein production may also be more effective if it simultaneously allows for higher levels of taurine or hypotaurine. Transport from the cellular medium into cells generally requires a higher concentration of these substrates in the medium and/or requires cellular energy for active transport.

Compositions containing taurine and taurine precursors

[241] Feed compositions are provided for use in aquaculture, or as animal feed, or as human nutritional supplements containing processed or unprocessed biomass from non- naturally occurring microorganism cells as described herein, as are methods of preparation of the feed compositions.

[242] The feed compositions or nutritional supplements include taurine and/or one or more taurine precursor(s), e.g., cysteate, sulfoacetaldehyde, and/or hypotaurine, produced by the non-naturally occurring microorganism. In some embodiments, taurine and/or taurine precursor(s) produced by the microorganism is encapsulated in the microorganism in the feed composition or supplement, e.g. , encapsulated in the lipid bilayer of the cell membrane of the microorganism. In some embodiments, taurine and/or taurine precursor(s) produced by the microbial biocatalyst is/are excreted into the culture medium and further purified, for example, using chromatographic or other separation and purification procedures. In some embodiments, taurine and/or taurine precursor(s) is/are chemically extracted from the producing microorganism.

[243] Taurine and/or taurine precursor(s) can be accumulated and encapsulated by the microorganism or can be exported outside the cell. Conditions required for export may be continuous during microbial growth or can be stimulated by limitation of nutrients, e.g., biotin, or by the presence of an inhibitor of microbial growth, such as an antibiotic or surfactant.

[244] In some embodiments, methods for separating and purifying taurine and/or taurine precursors from a culture containing microbial cells and microbially produced taurine may deploy ion exchange, e.g. , ion exchange resins. In some embodiments, microbial cells may be separated by centrifugation, condensed, or filtered, and taurine and/or taurine precursors concentrated to, for example, at least about 80% purity.

[245] In certain embodiments, biomass that is incorporated into a feed or nutritional supplement composition can be in a dry, or substantially dry, form, e.g., containing less than about 20%, 10%, 5%, or 2% of moisture. In certain embodiments, the cultures are isolated by removing substantially all supernatant, such as by filtering, sedimentation, or centrifugation. In certain embodiments, the collection of cultures and further processing of biomass excludes a bacterial lysis step, e.g. , by use of detergents or ultrasound. In certain embodiments, the processed microbial cells maintain substantially whole cell membranes. In some embodiments, a substantial portion (e.g. , more than about 5%, 10%, 20%, 30%, 50%, or 80%) of bacterial cells may maintain viability in the processed biomass.

[246] The feed composition may contain at least about 1% of the biomass by weight. In certain embodiments, the feed composition is optimized for consumption by fish, seafood, humans, or other animals. For example, the feed may include one or more of EPA, DHA, and one or more essential amino acids.

[247] Methods for preparing a feed composition are also provided. In some embodiments, the method includes: (a) culturing in an appropriate medium at least one non-naturally occurring microorganism as described above; (b) concentrating the medium to provide a biomass; (c) optionally providing additional feed components; and (d) producing the feed composition from the biomass. In certain embodiments, step (b) includes centrifugation. In certain embodiments, step (b) includes allowing the biomass to settle. In certain embodiments, step (b) includes filtration. In certain embodiments, the method further includes a pre-treatment of the biomass after step (a) with a chemical agent (e.g. , a surfactant or solvent) to disrupt the cell membranes of the biomass. In certain

embodiments, the method further includes mechanical disruption of the cell membranes of the biomass after step (a).

[248] Examples of feedstuffs into which single cell protein enriched with taurine and/or taurine precursors, produced as described herein, may be incorporated include, for example, pet foods, such as cat foods, dog foods and the like, feeds for aquarium fish, cultured fish or crustaceans, etc., feed for farm-raised animals (including livestock and further including fish or crustaceans raised in aquaculture). The state of the biomass can be in whole cell, lysed or partially processed. The taurine and/or taurine precursors and/or other caloric or nutritional supplements produced in described herein can also be incorporated into food or vitamin supplements for human consumption. Food or feed material into which taurine and/or taurine precursors produced as described herein is incorporated is preferably palatable to the organism that is the intended recipient. This food or feed material may have any physical properties currently known for a food material (e.g. , solid, liquid, soft). In some embodiments,, feed produced as described herein will undergo a pelletization process, e.g., through a hot or cold extrusion process at an inclusion rate of less than about 1%, 5%, 10%, 20%, 25%, 30%, 40%, 50%, 60%, or 75%. In other scenarios, the taurine and/or taurine precursors-enriched protein can be consumed directly at 100% or combined with another substance in the form of liquid, baked goods or other to form, including but not limited to, various types of tablets, capsules, drinkable agents, gargles, etc.

[249] Methods of producing fish or seafood are also provided, including farming fish or seafood, and providing a diet, which includes a feed composition as described herein, to the fish or seafood.

[250] The following examples are intended to illustrate, but not limit the invention.

EXAMPLES

Example 1

Methods:

[251] Expression plasmids were constructed utilizing standard molecular cloning techniques and codon optimized, synthetically-derived DNA (see Table 1). These plasmids were transformed into Methylobacterium extorquens or Escherichia coli BL21 (DE3).

[252] M. extorquens strains were grown in a minimal media based on Choi et al(1989) Appl Microbiol Bioeng 17:392-6). This media was amended with 0.5% methanol, lOug/mL trimethylprim, and 50ug/mL Kanamycin. For expression, a saturated M. extorquens culture was diluted 100 fold into 25mL of fresh media in a 250mL Erlenmeyer flask and shaken at 200rpm at 30°C. At 24 hours and 36 hours, cultures were fed an additional 0.5% methanol and induced with 0.0125-0.05ng/uL anhydrotetracycline (ATC). M. extorquens cultures were harvested between 48 and 52 hours. Following centrifugation, the bacterial pellets were washed once with 1/20X phosphate buffered saline (PBS) and frozen at -20°C.

[253] E. coli cultures were grown in LB (lOg Tryptone, lOg NaCl, 5g Yeast extract per liter) amended with lOOug/mL carbenicillin and 125uM isopropyl β-D-l- thiogalactopyranoside (IPTG). Following a 100-500 fold dilution, E. coli cultures were shaken at 200rpm at 30°C for 12-24 hours. Following centrifugation, the bacterial pellets were washed once with 1/20X PBS and frozen at -20°C.

[254] To induce chaperones to aid in protein folding, Betaine (Bet) or Benzyl alcohol (BA) were added at 5-10mm to cultures of E. coli or extorquens, as described in Marco et al. (2005) Cell Stress & Chaperones 10(4):329-339.

[255] For extraction of intracellular free amino acids, frozen bacterial pellets were resuspended in 1 :1 methanol: water and subjected to 3 to 4 freeze thaw cycles using dry- ice/ethanol slurry and a bath sonicator. Following centrifugation, the extraction supematants were derivatized with the Waters AccQ-Tag Ultra Chemistry kit (176001235) utilizing the provided protocols. Derivatized samples were analyzed on a Waters Acquity H-Class UPLC equipped with a 3100 Mass spectrophotometer. Samples were compared to the included amino acid standard amended with taurine, hypotaurine, and L-cysteate. The presence of taurine or hypotaurine was confirmed by the presence of mass spec ions matching the correct derivatized amino acid mass at the same retention time as in the standard samples. Results are in Table 2.

Results:

[256] Although the foregoing invention has been described in some detail by way of illustration and examples for purposes of clarity of understanding, it will be apparent to those skilled in the art that certain changes and modifications may be practiced without departing from the spirit and scope of the invention, which is delineated in the appended claims. Therefore, the description should not be construed as limiting the scope of the invention.

[257] All publications, patents, and patent applications cited herein are hereby incorporated by reference in their entireties for all purposes and to the same extent as if each individual publication, patent, or patent application were specifically and individually indicated to be so incorporated by reference.