文献类型：期刊文献

英文题名：AflQ1-Q2 represses lincomycin biosynthesis via multiple cascades in Streptomyces lincolnensis

作者：Wang, Ruida[1,2];Zhou, Tianyu[1,2];Kong, Fanjing[1,2];Hou, Bingbing[1,2];Ye, Jiang[1,2];Wu, Haizhen[1,2];Zhang, Huizhan[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Dept Appl Biol, Shanghai 200237, Peoples R China

年份：2023

卷号：107

期号：9

起止页码：2933

外文期刊名：APPLIED MICROBIOLOGY AND BIOTECHNOLOGY

收录：;EI(收录号：20231213750338);WOS:【SCI-EXPANDED(收录号:WOS:000952207200001)】；

基金：This work was supported by the National Key Research and Development Program of China (2021YFC2100600) and the National Natural Science Foundation of China (NSFC) (31900059).

语种：英文

外文关键词：AflQ1-Q2; Streptomyces lincolnensis; Two-component system; Lincomycin biosynthesis; Transcriptional regulation; Aspartate metabolism

摘要：Lincomycin is a broad-spectrum antibiotic and particularly effective against Gram-positive pathogens. Albeit familiar with the biosynthetic mechanism of lincomycin, we know less about its regulation, limiting the rational design for strain improvement. We therefore analyzed two-component systems (TCSs) in Streptomyces lincolnensis, and selected eight TCS gene(s) to construct their deletion mutants utilizing CRISPR/Cas9 system. Among them, lincomycin yield increased in two strains (Delta 3900-3901 and Delta 5290-5291) while decreased in other four strains (Delta 3415-3416, Delta 4153-4154, Delta 4985, and Delta 7949). Considering the conspicuous effect, SLINC_5291-5290 (AflQ1-Q2) was subsequently studied in detail. Its repression on lincomycin biosynthesis was further proved by gene complementation and overexpression. By binding to a 16-bp palindromic motif, the response regulator AflQ1 inhibits the transcription of its encoding gene and the expression of eight operons inside the lincomycin synthetic cluster (headed by lmbA, lmbJ, lmbK, lmbV, lmbW, lmbU, lmrA, and lmrC), as demonstrated by quantitative RT-PCR and electrophoretic mobility shift assays. Besides, the regulatory genes including bldD, glnR, lcbR1, and ramR are also regulated by the TCS. According to the screening towards nitrogen sources, aspartate affects the regulatory behavior of histidine kinase AflQ2. And in return, AflQ1 accelerates aspartate metabolism via ask-asd, asd2, and thrA. In summary, we acquired six novel regulators related to lincomycin biosynthesis, and elucidated the regulatory mechanism of AflQ1-Q2. This highly conserved TCS is a promising target for the construction of antibiotic high-yield strains.