RRC ID 33534
著者 Yamamoto H, Murata M, Sekiguchi J.
タイトル The CitST two-component system regulates the expression of the Mg-citrate transporter in Bacillus subtilis.
ジャーナル Mol Microbiol
Abstract citS and citT genes encoding a new two-component system were identified in the 71 degrees region between the pel and citM loci on the Bacillus subtilis chromosome. citS- and citT-deficient strains were unable to grow on minimal plates including citrate as a sole carbon source. In addition, a strain deficient in citM, which encodes the secondary transporter of the Mg-citrate complex, exhibited the same phenotype on this medium. Northern blot analysis revealed that citM was polycistronically transcribed with the downstream yflN gene, and that CitS and CitT were necessary for transcription of the citM-yflN operon. Upon addition of 2 mM citrate to DSM, this operon was strongly induced after the middle of the exponential growth phase in the wild type, but not in the citST double null mutant. Moreover, the transcription of this operon was completely repressed in the presence of 1% glucose. We found a sequence exhibiting homology to a catabolite-responsive element (cre) in the citM promoter region. Glucose repression was lost in ccpA and citM-cre mutants. From the result of a citM-promoter deletion experiment, putative CitT target sequences were found to be located around two regions, from -62 to -74 and from -149 to -189, relative to the citM start point. Furthermore, DNase I footprinting assays revealed that these two CitT target regions extended maximally from -36 to -84 and from -168 to -194. From these findings, we concluded that the expression of citM is positively regulated by the CitST system and negatively regulated by CcpA.
巻・号 37(4)
ページ 898-912
公開日 2000-8-1
DOI 10.1046/j.1365-2958.2000.02055.x
PII mmi2055
PMID 10972810
MeSH Amino Acid Sequence Bacillus subtilis / genetics* Bacillus subtilis / growth & development Bacillus subtilis / metabolism Bacterial Proteins* Base Sequence Carrier Proteins / genetics* Carrier Proteins / physiology* Cell Division / physiology DNA Footprinting DNA, Bacterial Escherichia coli Proteins* Gene Expression Regulation, Bacterial / physiology* Molecular Sequence Data Operon Organic Anion Transporters* Promoter Regions, Genetic Symporters Transcription, Genetic / physiology
IF 3.418
引用数 70
WOS 分野 MICROBIOLOGY BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
原核生物(枯草菌) MBS66 MBS64 MBS65