Genetic Determination of Methylenomycin Synthesis by the SCP1 Plasmid of Streptomyces coelicolor A3(2)

Abstract

Genes determining the pathway of methylenomycin A synthesis are carried on the SCP1 plasmid. All 16 mutations (mmy) leading to lack of antibiotic synthesis were SCP1-linked. Phenotypic classification by co-synthesis and other criteria suggested that they fell into at least 5 classes. When the wild-type SCP1 plasmid was transferred to S. lividans or S. parvulus, material that was chromatographically and biologically indistinguishable from methylenomycin A was produced. Recombination between some pairs of mmy mutations was detected. In crosses of mmy mutants of NF (integrated SCP1 donor) strains with SCP1-, a very high frequency of chromosomal recombination occurred; methylenomycin production appears not to be an important cause of the ultra-fertility normally associated with NF .times. SCP1- crosses.