The enzymes from the Gram-positive bacteria Streptomyces sp. C5 and Streptomyces peucetius are involved in the biosynthesis of the anthracycline daunorubicin. In vitro the enzyme from Streptomyces sp. C5 also catalyses the 4-O-methylation of 13-dihydrocarminomycin, rhodomycin D and 10-carboxy-13-deoxycarminomycin [3].