Mycolic acid-containing bacteria induce the production of novel secondary metabolites in streptomyces strains

Abstract

It was previously reported that several kinds of mycolic acid-containing bacteria interact with various kinds of Streptomyces strains and induce the secondary metabolites production (Onaka, H. et al. Appl. Environ. Microbiol. 2011, 77, 400 – 406). We applied this fermentation method to our collection of Streptomyces strains, employing Tsukamurella pulmonis as a mycolic acid-containing bacterium. As a result, novel cytotoxic alkaloid arcyriaflavin E (1) was isolated from Streptomyces cinnamoneus NBRC 13823 and novel cytotoxic butanolides chojalactones A-C (2-4) were obtained from soil-derived Streptomyces CJ-5 respectively. The stereochemistries (including absolute configurations) of 2-4 were determined based on careful spectroscopic analysis and the total synthesis of 2 and 3, together with all of their stereoisomers.