Redox-sensing regulator Rex regulates aerobic metabolism, morphological differentiation, and avermectin production in Streptomyces avermitilis.
Redox-sensing regulator Rex regulates aerobic metabolism, morphological differentiation, and avermectin production in Streptomyces avermitilis.
复制标题
氧化还原传感调节剂 Rex 调节阿维链霉菌的有氧代谢、形态分化和阿维菌素生产
DOI：
10.1038/srep44567
复制
发表时间：
2017-03-17
影响因子：
4.6
通讯作者：
Li J
中科院分区：
文献类型：
--
作者：
Liu X;Cheng Y;Lyu M;Wen Y;Song Y;Chen Z;Li J
研究了氧化还原感应调节剂Rex对阿维霉的调控作用。11个基因/操纵子被证实受Rex直接调控；这些基因/操纵子参与有氧代谢、形态分化和次生代谢。Rex通过结合启动子区域的Rex算子（ROP）序列来抑制靶基因/操纵子的转录。NADH降低了Rex对目标启动子的dna结合活性，而NAD+竞争性地与Rex结合并调节其dna结合活性。Rex通过控制呼吸基因atpIBEFHAGDC、cydA1B1CD、nuoA1-N1、Rex - hemac1db、hppA和ndh2的表达，在有氧代谢中发挥重要的调节作用。Rex还通过抑制wblE的表达来调节形态分化，wblE编码一个假定的whb家族转录调节因子。一个rex-缺失突变体（Drex）比野生型菌株ATCC31267的阿维菌素产量更高，并且在阿维菌素产量方面更耐受限氧条件。
The regulatory role of redox-sensing regulator Rex was investigated in Streptomyces avermitilis. Eleven genes/operons were demonstrated to be directly regulated by Rex; these genes/operons are involved in aerobic metabolism, morphological differentiation, and secondary metabolism. Rex represses transcription of target genes/operons by binding to Rex operator (ROP) sequences in the promoter regions. NADH reduces DNA-binding activity of Rex to target promoters, while NAD+ competitively binds to Rex and modulates its DNA-binding activity. Rex plays an essential regulatory role in aerobic metabolism by controlling expression of the respiratory genes atpIBEFHAGDC, cydA1B1CD, nuoA1-N1, rex-hemAC1DB, hppA, and ndh2. Rex also regulates morphological differentiation by repressing expression of wblE, which encodes a putative WhiB-family transcriptional regulator. A rex-deletion mutant (Drex) showed higher avermectin production than the wild-type strain ATCC31267, and was more tolerant of oxygen limitation conditions in regard to avermectin production.