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In this study, we aimed to develop recombinant Saccharomyces cerevisiae with increased long-chain fatty acids by expressing essential genes involved in fatty acid synthesis elongation cycle. The relation of β-ketoacyl-ACP synthase II ( fabF) from S. cerevisiae YPH500 and 3-oxoacyl-[acyl-carrier-protein] reductase ( fabG), 3-hydroxyacyl-thioester dehydratase ( FabZ), enoyl-ACP reductase ( FabK), and acyl-ACP thioesterase ( EC.3.1.2.14) from Streptococcus pyogenes MGAS 10270 regarding fatty acid production was investigated. These genes were separately cloned, and the effects of respective genes on fatty acid production were analyzed. Compared with the wild type S. cerevisiae, fabF recombinant (SGJY01) showed about 1.8-fold enhanced fatty acid production. We also exhibited thermal regulation in the fatty acid composition of SGJY01 changed at lower temperatures. The fabF recombinant and wild-type were cultured at different temperatures (30, 20, and 10°C), resulting the unsaturated fatty acids (C16:1 and C18:1) increased up to 2.4-fold as compared to the wild-type. Of particular interest is that the proportion of unsaturated fatty acids was increased approximately 11.8% at 10°C compared to 30°C, although the proportion in the wild-type remained unchanged. [ABSTRACT FROM AUTHOR]

Abstract: Natural products continue to serve as one of the best sources for discovery of antibacterial agents as exemplified by the recent discoveries of platensimycin and platencin. Chemical modifications as well as discovery of congeners are the main sources for gaining knowledge of structure–activity relationship of natural products. Screening for congeners in the extracts of the fermentation broths of Streptomyces platensis led to the isolation of platencin A1, a hydroxy congener of platencin. The hydroxylation of the tricyclic enone moiety negatively affected the antibacterial activity and appears to be consistent with the hydrophobic binding pocket of the FabF. Isolation, structure, enzyme-bound structure and activity of platencin A1 and two other congeners have been described. [Copyright &y& Elsevier]