Effective Production of Potent Cell Cycle Inhibitor Dehydrophenylahistin by a Combination of Chemical Racemization and Streptomyces Enzyme-catalyzed Conversion

Abstract

An effective method was established for preparing the potent cell cycle inhibitor dehydrophenylahistin by a combination of chemical racemization of partially purified (±)-phenylahistin and enzymatic conversion of (−)-phenylahistin by the cell-free extract of Streptomyces albulus KO-23, an albonoursin-producing actinomycete. This method enables conversion of (+)-phenylahistin, which is present in the culture of Aspergillus ustus NSC-F038 and is not transformed by the Streptomyces enzyme, to dehydrophenylahistin.