title: Redox-sensing regulator Rex regulates aerobic metabolism, morphological differentiation, and avermectin production in Streptomyces avermitilis.
abstract: 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.
authors.affiliation: State Key Laboratory of Agro-biotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Xingchao
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agro-biotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Yaqing
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Agro-biotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Mengya
authors.initials: M
authors.lastname: Lyu
authors.affiliation: State Key Laboratory of Agro-biotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wen
authors.affiliation: State Key Laboratory of Agro-biotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Song
authors.affiliation: State Key Laboratory of Agro-biotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Agro-biotechnology and MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Jilun
authors.initials: J
authors.lastname: Li
mesh_terms: D000332:Aerobiosis / Q000235:genetics; D001665:Binding Sites; D002454:Cell Differentiation / Q000235:genetics*; D019069:Cell Respiration / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D016370:Gene Products, rex / Q000235:genetics* / Q000378:metabolism; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000378:metabolism; D010084:Oxidation-Reduction; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D013302:Streptomyces / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D004268:DNA-Binding Proteins; D016370:Gene Products, rex; D007559:Ivermectin; C019264:avermectin