A putative redox‐sensing regulator Rex regulates lincomycin biosynthesis in Streptomyces lincolnensis

Abstract

Lincomycin is an important antimicrobial agent which is widely used in clinical and animal husbandry. The biosynthetic pathway of lincomycin comes to light in the past 10 years, however, the regulatory mechanism is still unclear. In this study, a redox-sensing regulator Rex from Streptomyces lincolnensis (Rex lin ) was identified and characterized to affect cell growth and lincomycin biosynthesis. Disruption of rex resulted in an increase in cell growth, but a decrease in lincomycin production. The results of quantitative real-time polymerase chain reaction showed that Rex lin can promote transcription of the regulatory gene lmbU and the structural genes lmbA, lmbC, lmbJ, lmbV, and lmbW. However, electrophoretic mobility shift assay analysis demonstrated that Rex lin can not bind to the promoter regions of these genes above. Findings in this study broadened our horizons in the regulatory mechanism of lincomycin production and laid a foundation for strain improvement of antibiotic producers.

PAS domain containing regulator SLCG_7083 involved in morphological development and glucose utilization in Streptomyces lincolnensis

“…In addition, they also play other regulation roles in S. lincolnensis : GlnR up-regulates the transcription of nitrate-specific ABC transporter and nitrate assimilation genes [ 17 ]; SLCG_2919 negatively regulates its adjacent gene SLCG_2920 encoding a lincomycin resistance protein [ 18 ]; BldD positively regulates the sporulation [ 19 ]; AdpA activates the bldA gene for the cascade regulation of lincomycin biosynthesis [ 20 ]; Lrp is transcriptionally self-inhibited and activates its adjacent gene SLCG_3127 encoding LysE protein; RamR affects cell growth in S. lincolnensis [ 22 ]. Besides, the redox-sensing regulator Rex directly controls the expression of g lnR and ramC , to indirectly regulate lincomycin biosynthesis and morphology, respectively [ 23 ].…”