Nitric oxide-sensitive and -insensitive interaction of Bacillus subtilis NsrR with a ResDE-controlled promoter.

Autor: Kommineni S; Department of Science & Engineering, School of Medicine, Oregon Health & Science University, 20000 NW Walker Road, Beaverton, OR 97006, USA., Yukl E, Hayashi T, Delepine J, Geng H, Moënne-Loccoz P, Nakano MM
Jazyk: angličtina
Zdroj: Molecular microbiology [Mol Microbiol] 2010 Dec; Vol. 78 (5), pp. 1280-93. Date of Electronic Publication: 2010 Oct 08.
DOI: 10.1111/j.1365-2958.2010.07407.x
Abstrakt: NsrR is a nitric oxide (NO)-sensitive transcription repressor that controls NO metabolism in a wide range of bacteria. In Bacillus subtilis, NsrR represses transcription of the nitrite reductase (nasDEF) genes that are under positive control of the ResD-ResE two-component signal transduction system. Derepression is achieved by reaction of NO with NsrR. Unlike some NsrR orthologues that were shown to contain a NO-sensitive [2Fe-2S] cluster, B. subtilis NsrR, when purified anaerobically either from aerobic or from anaerobic Escherichia coli and B. subtilis cultures, contains a [4Fe-4S] cluster. [4Fe-4S]-NsrR binds around the -35 element of the nasD promoter with much higher affinity than apo-NsrR and binding of [4Fe-4S]-NsrR, but not apo-protein, is sensitive to NO. RNA polymerase and phosphorylated ResD make a ternary complex at the nasD promoter and NsrR dissociates the preformed ternary complex. In addition to the -35 region, NsrR binds to two distinct sites of the upstream regulatory region where ResD also binds. These interactions, unlike the high-affinity site binding, do not depend on the NsrR [4Fe-4S] cluster and binding is not sensitive to NO, suggesting a role for apo-NsrR in transcriptional regulation.
(© 2010 Blackwell Publishing Ltd.)
Databáze: MEDLINE
Externí odkaz: