Molecular analysis of an anion pump: purification of the ArsC protein.
The ars operon of resistance plasmid R773 encodes an anion-translocating ATPase which catalyzes extrusion of the oxyanions arsenite, antimonite, and arsenate, thus providing resistance to the toxic compounds. Although both arsenite and arsenate contain arsenic, they have different chemical properties. In the absence of the arsC gene the pump transports arsenite and antimonite, oxyanions with the +III oxidation state of arsenic or antimony. The complex neither transports nor provides resistance to arsenate, the oxyanion of the +V oxidation state of arsenic. The arsC gene encodes a 16-kDa polypeptide, the ArsC protein, which alters the substrate specificity of the pump to allow for recognition and transport of the alternate substrate arsenate. The arsC gene was cloned behind a strong promoter and expressed at high levels. The ArsC protein was purified and crystallized.
Department of Biochemistry, Wayne State University School of Medicine, Detroit, Michigan 48201.
B P
BP
Rosen
U
U
Weigel
R A
RA
Monticello
B P
BP
Edwards
D000251:Adenosine Triphosphatases / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D000595:Amino Acid Sequence; D000965:Antimony / Q000494:pharmacology; D001149:Arsenates / Q000494:pharmacology; D001151:Arsenic / Q000494:pharmacology; D053501:Arsenite Transporting ATPases; D018053:Arsenites; D001395:Azotobacter / Q000235:genetics; D004351:Drug Resistance; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D016623:Ion Pumps; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes; D009876:Operon; D010957:Plasmids
D001149:Arsenates; D018053:Arsenites; D007473:Ion Channels; D016623:Ion Pumps; D009097:Multienzyme Complexes; C061374:antimonite; D000965:Antimony; D000251:Adenosine Triphosphatases; D053501:Arsenite Transporting ATPases; C015001:arsenite; D001151:Arsenic; C025657:arsenic acid