Kaur P, Rosen B P
Department of Biochemistry, Wayne State University, School of Medicine, Detroit, Michigan 48201.
Plasmid. 1992 Jan;27(1):29-40. doi: 10.1016/0147-619x(92)90004-t.
Resistance determinants to the toxic oxyanionic salts of arsenic and antimony are found on plasmids of both gram-negative and gram-positive organisms. In most cases these provide resistance to both the oxyanions of +III oxidation state, antimonite and arsenite, and the +V oxidation state, arsenate. In both gram-positive and -negative bacteria, resistance is correlated with efflux of the anions from cells. The determinant from the plasmid R773, isolated from a gram-negative organism, has been studied in detail. It encodes an oxyanion-translocating ATPase with three subunits, a catalytic subunit, the ArsA protein, a membrane subunit, the ArsB subunit, and a specificity factor, the ArsC protein. The first two form a membrane-bound complex with arsenite-stimulated ATPase activity. The determinants from gram-positive bacteria have only the arsB and arsC genes and encode an efflux system without the participation of an ArsA homologue.
对砷和锑的有毒含氧阴离子盐的抗性决定因素存在于革兰氏阴性菌和革兰氏阳性菌的质粒上。在大多数情况下，这些因素对 +III 氧化态的含氧阴离子（亚锑酸盐和亚砷酸盐）以及 +V 氧化态的砷酸盐均具有抗性。在革兰氏阳性菌和阴性菌中，抗性均与阴离子从细胞中的流出相关。从革兰氏阴性菌中分离出的质粒 R773 上的决定因素已得到详细研究。它编码一种具有三个亚基的含氧阴离子转运 ATP 酶，一个催化亚基 ArsA 蛋白、一个膜亚基 ArsB 亚基和一个特异性因子 ArsC 蛋白。前两者形成一个与亚砷酸盐刺激的 ATP 酶活性相关的膜结合复合物。革兰氏阳性菌的决定因素仅具有 arsB 和 arsC 基因，并编码一个无需 ArsA 同源物参与的流出系统。
