Generation and study of the strains of streptomycetes-heterologous hosts for the production of moenomycin

Heterologous expression of the moenomycin biosynthesis gene cluster (moe) would be one of the ways to reach this goal. Here, we report the generation of a number of novel heterologous streptomycete hosts producing nosokomycin A₂ (one of the members of Mm family) and determine their potential for the antibiotic production. The rpoB point mutation in the model strain of Streptomyces coelicolor (strain M1152) significantly improved nosokomycin A₂ production compared to parental strains (M145 and M512), while double rpoBrpsL mutation in the same species (strain M1154) decreased it. Our results point to the previously unanticipated epistatic interactions between mutations that individually are known to be highly beneficial for antibiotic production. We also showed here for the first time that facultative chemolitotrophic streptomycete S. thermospinosisporus and chloramphenicol producer S. venezuelae can be used as the hosts for moe genes.