EXPRESSION CASSETTES USEFUL IN CONSTRUCTION OF INTEGRATIVE AND REPLICATIVE EXPRESSION VECTORS FOR STREPTOMYCES

摘要

The present invention is directed to expression cassettes useful in gene expression studies in both homologous and heterologous Streptomyces strains. More specifically the present invention is directed to the construction of two Streptomyces lividans-recombinant strains capable of producing 31-O-desmethylFK-506 O:methyltransferase, which methylates 31-O-desmethylFK-506 to FK-506. In addition, the present invention is directed to a process for the specific methylation of 31-desmethyl-FK506 to FK506.