Effect of S-Adenosylmethionine on Antibiotic Production in Streptomyces griseus and Streptomyces griseoflavus

S-Adenosylmethionine caused overproduction of streptomycin (by Streptomyces griseus) and bicozamycin (by Streptomyces griseoflavus) when added to the medium at an appropriate concentration. The enhancement of streptomycin production was accompanied by a 1.35-fold increase in transcript of strR (a pathway-specific positive regulatory gene), and a 1.9-fold increase in activity of streptomycin kinase (an enzyme for streptomycin biosynthesis). These results, together with the previous works dealing with Streptomyces coelicolor (J. Bacteriol. 185, 601–609, 2003) and Streptomyces lividans (J. Bacteriol, 185, 592–600, 2003), implicate the significance of S-adenosylmethionine as an intracellular signal molecule for onset of secondary metabolism in the Streptomyces species.