Biological Synthesis of Polyketides from 6-n-Pentyl-α-pyrone by Streptomyces sp.

Selectivity is an essential requirement in synthetic organic chemistry. The regioselectivity of enzymes even on complex or symmetric molecules without any need of protecting groups is a fundamental strength of biocatalysis. Biocatalysis are also a powerful tool for the regioselective and enantioselective synthesis of bioactive compounds, as well as for the generation of new, active, and less toxic derivatives for the bioactive natural products. The symmetric dipyrroloquinone, terreusinone, was regioselectively biotransformed to its unsymmetrical alcohol derivative, terreusinol, by the marine actinomycete Streptomyces sp. (MFAac18), which was isolated from a sample of sea plant Zostera marina collected at Bijin Island, Gyeongnam, using YPG (yeast, peptone, and glucose) agar medium. In our continuing studies of the application of biocatalysis, we investigated the microbial transformation for 6-n-pentyl-α-pyrone (1), which had been isolated as the antityrosinase active component from the marine isolate of the fungus Myrothecium sp. We wish to report the biological synthesis 6-n-(4-oxopentyl)-α-pyrone (2) and 6-n-[(1S)-hydroxypentyl]-α-pyrone (3) from 6-n-pentyl-α-pyrone (1) by Streptomyces sp. (MFAac18).