| 摘要 |
It has been required to economically produce a large amount of optically active gamma -lactone derivatives (for example, pantolactone), which are useful as intermediates in synthesizing useful substances such as pharmaceutical drugs. To achieve this object, it is advantageous to employ an enzymatic technique of asymmetric hydrolysis with a hydrolyzing enzyme lactonase. However, it remains troublesome to prepare the enzyme or utilize a microorganism capable of producing the enzyme. Also, it is difficult to obtain a sufficient and stable enzymatic activity in the case of using recombination techniques. In producing lactonase, which asymmetrically hydrolyzes a gamma -lactone derivative such as racemic pantolactone selectively, by a recombination technique, both mature lactonase DNA and signal peptide region DNA are transferred into a host. Thus, a stable lactonase activity comparable to naturally-occurring one can be achieved and a transformant sustaining a high enzyme activity in a stable manner can be acquired, thereby allowing the efficient and industrially advantageous asymmetric synthesis of gamma -lactone derivatives. |
