RRC ID 27700
著者 Toyoda K, Teramoto H, Gunji W, Inui M, Yukawa H.
タイトル Involvement of regulatory interactions among global regulators GlxR, SugR, and RamA in expression of ramA in Corynebacterium glutamicum.
ジャーナル J Bacteriol
Abstract The central carbon metabolism genes in Corynebacterium glutamicum are under the control of a transcriptional regulatory network composed of several global regulators. It is known that the promoter region of ramA, encoding one of these regulators, interacts with its gene product, RamA, as well as with the two other regulators, GlxR and SugR, in vitro and/or in vivo. Although RamA has been confirmed to repress its own expression, the roles of GlxR and SugR in ramA expression have remained unclear. In this study, we examined the effects of GlxR binding site inactivation on expression of the ramA promoter-lacZ fusion in the genetic background of single and double deletion mutants of sugR and ramA. In the wild-type background, the ramA promoter activity was reduced to undetectable levels by the introduction of mutations into the GlxR binding site but increased by sugR deletion, indicating that GlxR and SugR function as the transcriptional activator and repressor, respectively. The marked repression of ramA promoter activity by the GlxR binding site mutations was largely compensated for by deletions of sugR and/or ramA. Furthermore, ramA promoter activity in the ramA-sugR double mutant was comparable to that in the ramA mutant but was significantly higher than that in the sugR mutant. Taken together, it is likely that the level of ramA expression is dynamically balanced by GlxR-dependent activation and repression by RamA along with SugR in response to perturbation of extracellular and/or intracellular conditions. These findings add multiple regulatory loops to the transcriptional regulatory network model in C. glutamicum.
巻・号 195(8)
ページ 1718-26
公開日 2013-4-1
DOI 10.1128/JB.00016-13
PII JB.00016-13
PMID 23396909
PMC PMC3624568
MeSH Bacterial Proteins / genetics Bacterial Proteins / metabolism* Binding Sites Corynebacterium glutamicum / genetics Corynebacterium glutamicum / metabolism* DNA, Bacterial DNA, Intergenic Down-Regulation Escherichia coli / genetics Escherichia coli / metabolism Gene Expression Regulation, Bacterial / physiology* Mutation Plasmids Promoter Regions, Genetic Protein Binding RNA, Bacterial / genetics RNA, Bacterial / metabolism RNA, Messenger / genetics RNA, Messenger / metabolism Transcription, Genetic
IF 3.006
引用数 13
WOS 分野 MICROBIOLOGY
リソース情報
一般微生物 JCM 18229