PURPOSE: To produce biotin efficiently, by cultivating a transformed variant of Escherichia coli containing a specific DNA as a plasmid in a medium containing dethiobiotin, and collecting biotin accumulated in the medium.
CONSTITUTION: TK101, one of α-dehydrobiotin resistant strains derived from Escherichia coli JA221 is transduced with Eschrichia coli plasmid pNS5 having a DNA to code biotin synthase by transformation method, to give transformed strain NS105. Then, this NS105 is cultivated in peptone Casamino acid medium containing 50mg/l amplicillin, 100×M dl-dethiobiotin, and 2mM isopropyl β-D- thiogalactopyranoside at about 37°C for about 24hr. Dethiobiotin in the medium is converted into biotin in 100% yield by this cultivation. Then, the culture solution is centrifuged and biotin is separated from the supernatant liquid.
KOJIMA TAKAKAZU
KIMURA HITOSHI
