ArsR arsenic-resistance regulatory protein from Cupriavidus metallidurans CH34.
The Cupriavidus metallidurans CH34 arsR gene, which is part of the arsRIC(2)BC(1)HP operon, and its putative arsenic-resistance regulatory protein were identified and characterized. The arsenic-induced transcriptome of C. metallidurans CH34 showed that the genes most upregulated in the presence of arsenate were all located within the ars operon, with none of the other numerous heavy metal resistance systems present in CH34 being induced. A transcriptional fusion between the luxCDABE operon and the arsR promoter/operator (P/O) region was used to confirm the in vivo induction of the ars operon by arsenite and arsenate. The arsR gene was cloned into expression vectors allowing for the overexpression of the ArsR protein as either his-tagged or untagged protein. The ability of the purified ArsR proteins to bind to the ars P/O region was analyzed in vitro by gel mobility shift assays. ArsR showed an affinity almost exclusively to its own ars P/O region. Dissociation of ArsR and its P/O region was metal dependent, and based on decreasing degrees of dissociation three groups of heavy metals could be distinguished: As(III), Bi(III), Co(II), Cu(II), Ni(II); Cd(II); Pb(II) and Zn(II), while no dissociation was observed in the presence of As(V).
Zhang
Yian-Biao
YB
Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
Monchy
Sébastien
S
Greenberg
Bill
B
Mergeay
Max
M
Gang
Oleg
O
Taghavi
Safiyh
S
van der Lelie
Daniel
D
D001149:Arsenates / Q000494:pharmacology; D001151:Arsenic / Q000378:metabolism / Q000494:pharmacology*; D018053:Arsenites / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D049921:Cupriavidus / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D024881:Drug Resistance, Bacterial; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D009876:Operon / Q000187:drug effects; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
D001149:Arsenates; D018053:Arsenites; D001426:Bacterial Proteins; D015534:Trans-Activators; C015001:arsenite; D001151:Arsenic; C025657:arsenic acid