| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing a highly β-galactosidase-producing mutant microorganism not receiving a catabolite repression caused by a saccharide contained in a general culture medium, to provide the mutant microorganism produced by the production method, and to provide a method for producing galactooligosaccharide with the β-galactosidase produced by the mutant microorganism. <P>SOLUTION: This method for producing the highly β-galactosidase-producing mutant microorganism is characterized by comprising the following processes (a) to (c). (a) A process for applying a mutation treatment to a parent microorganism produced by the β-galactosidase. (b) A process for culturing the mutation-treated microorganism in a culture medium containing lactose and a substance analogous to a saccharide inhibiting the β-galactosidase production of the parent microorganism. (c) A process for again culturing the microorganism cultured in the process (b) in a culture medium containing the saccharide inhibiting the β-galactosidase production of the parent microorganism as a single carbon source and then selecting the microorganism producing the β-galactosidase from the cultured microorganisms. <P>COPYRIGHT: (C)2004,JPO |
