Rosen B P, Hsu C M, Karkaria C E, Kaur P, Owolabi J B, Tisa L S
Department of Biochemistry, Wayne State University, School of Medicine, Detroit, MI 48201.
Biochim Biophys Acta. 1990 Jul 25;1018(2-3):203-5. doi: 10.1016/0005-2728(90)90249-4.
An anion-translocating ATPase has been identified as the product of the arsenical resistance operon of resistance plasmid R773. When expressed in Escherichia coli this ATP-driven oxyanion pump catalyzes extrusion of the oxyanions arsenite, antimonite and arsenate. Maintenance of a low intracellular concentration of oxyanion produces resistance to the toxic agents. The pump is composed of two polypeptides, the products of the arsA and arsB genes. This two-subunit enzyme produces resistance to arsenite and antimonite. A third gene, arsC, expands the substrate specificity to allow for arsenate pumping and resistance.
一种阴离子转运ATP酶已被鉴定为耐药质粒R773砷抗性操纵子的产物。当在大肠杆菌中表达时，这种由ATP驱动的氧阴离子泵催化亚砷酸盐、亚锑酸盐和砷酸盐等氧阴离子的外排。维持细胞内低浓度的氧阴离子可产生对这些有毒物质的抗性。该泵由两种多肽组成，即arsA和arsB基因的产物。这种双亚基酶产生对亚砷酸盐和亚锑酸盐的抗性。第三个基因arsC扩展了底物特异性，使得能够进行砷酸盐的转运并产生抗性。
