PURPOSE: To obtain a recombinant type enzyme capable of producing a glucide, useful for sweetening a food and drink without any anxiety about coloring arid deteriorating and having a trehalose structure from a starch saccharide.
CONSTITUTION: This recombinant type enzyme is capable of producing a nonreducing glucide having a trehalose structure at the terminal obtained from a reducing starch saccharide having ≥3 glucose polymerization degree and has the following physico-chemical properties: (1) about 76000 to 87000Da molecular weight measured by a sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis; (2) about 3.6-4.6 isoelectric point measured by an isoelectric focusing; (3) 35-40°C optimum temperature; (4) 6.4-7.2 optimum pH and (5) stable to about 35-40'C by incubation at pH 7.0 for 60min and stable at about pH 5.5-11.0 by incubation at 25°C for 16hr. The recombinant type enzyme has, e.g. an amino acid sequence expressed by the formula and is obtained from a culture of a transformant BMT7, etc., prepared by using a chromosomal DNA of Rhizobium sp. M-11 (FERM BP-4130), etc.
TSUSAKI KEIJI
MARUTA KAZUHIKO
SUGIMOTO TOSHIYUKI
