Acquisition of ionic copper by the bacterial outer membrane protein OprC through a novel binding site.
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ABSTRACT:
SUBMITTER: Bhamidimarri SP
PROVIDER: S-EPMC8610252 | biostudies-literature |
REPOSITORIES: biostudies-literature
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2014-04-29 | E-GEOD-57136 | biostudies-arrayexpress
Project description:Intracellular zinc concentration needs to be maintained within strict limits due to its toxicity at high levels, and this is achieved by a finely regulated balance between uptake and efflux. Many bacteria use the Zinc Uptake Regulator Zur to orchestrate zinc homeostasis, but little is known regarding the transport of this metal across the bacterial outer membrane. In this work we determined the C. crescentus Zur regulon by global transcriptional and in silico analyses. Among the genes directly repressed by Zur are those encoding a putative high affinity ABC uptake system (znuCBA), three TonB-dependent receptors (znuD, znuE and znuF) and one new putative transporter of a family not yet characterized (zrpW). Zur is also directly involved in the activation of a RND and a P-type ATPase efflux systems, as revealed by β-galactosidase and site-directed mutagenesis assays. Several genes belonging to the Fur regulon were also downregulated in the zur mutant, suggesting a putative cross-talk between Zur and Fur regulatory networks. Interestingly, a phenotypic analysis of the znuD and znuE mutants has shown that these genes are essential for growth under zinc starvation, suggesting that C. crescentus uses these TonB-dependent outer membrane transporters as key zinc scavenging systems.
2014-04-29 | GSE57136 | GEO