羟基多氯联苯与人和大鼠羟基固醇类硫酸基转移酶的相互作用

目的:多氯联苯(Polychlorinated biphenyls,PCBs)是一类持久性环境污染物,对人类健康有潜在危害。羟基多氯联苯(Hydroxylated PCBs,OH-PCBs)是PCBs在体内的生物活性形式;已有报道OH-PCBs是多种亚型的酚类硫酸基转移酶(Sulfo-transferases,SULTs)抑制剂和底物,本研究拟观察OH-PCBs与人和大鼠羟基固醇类SULT有无相互作用。方法:采用重组表达人羟基固醇类SULT(SULT2A1)和其大鼠同源酶SULT2A3的大肠杆菌菌株,分离纯化所表达的酶蛋白;分析3种OH-PCBs的酶促硫酸基结合或抑制生理性底物结合反应的活性;以辅酶转化产物3’,5’-二磷酸腺苷(Adenosine 3’,5’-diphosphate,PAP)形成反映酶促硫酸基结合的水平。结果:4-OH PCB 34和4’-OH PCB 68一定浓度(1～200μmol/L)对人SULT2A1具有底物活性;二者都存在底物抑制(在50μmol/L以上抑制明显)。4’-OH PCB 9对此酶不具底物活性,但对去氢表雄酮(Dehydroepiandros-terone,DHEA)和...

Interactions of hydroxylated polychlorinated biphenyls with human and rat hydroxysteroid sulfotransferases

Objective:Polychlorinated biphenyls(PCBs) are a group of persistent pollutants,which are potentially harmful to human health.Hydroxylated PCBs(OH-PCBs) are the biologically active form of PCBs,and there have been reports that OH-PCBs are potent inhibitors of phenol sulfotransferases(SULTs);the present study was to investigate the interactions between OH-PCBs and hydroxysteroid SULTs of human and rat.Methods:Recombinant E.coli strains expressing human hydroxysteroid SULT(SULT2A1) and its rat homologous enzym...