TetR-Type Regulator SLCG_2919 Is a Negative Regulator of Lincomycin Biosynthesis in Streptomyces lincolnensis

TetR family transcriptional regulators (TFRs) are generally found to regulate diverse cellular processes in bacteria, especially antibiotic biosynthesis inStreptomyces species. However, knowledge of their function in lincomycin biosynthesis inS. lincolnensis remains unknown. The present study provides a new insight into the regulation of lincomycin biosynthesis through a TFR, SLCG_2919, that directly modulates lincomycin production and resistance. Intriguingly,SLCG_2919 and its adjoining gene,SLCG_2920 , which encodes an ATP/GTP binding protein, were extensively distributed in diverseStreptomyces species. In addition, we revealed a new TFR binding motif, in which SLCG_2919 binds to the promoter region ofSLCG_2920 , dependent on the intervening AT-rich sequence rather than on the flanking inverted repeats found in the binding sites of other TFRs. These insights into transcriptional regulation of lincomycin biosynthesis by SLCG_2919 will be valuable in paving the way for genetic engineering of regulatory elements inStreptomyces species to improve antibiotic production.