Konishi-Imamura L, Kim D H, Koizumi M, Kobashi K
Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Japan.
J Enzyme Inhib. 1995;8(4):233-41. doi: 10.3109/14756369509020130.
Arylsulfate sulfotransferase (ASST) from a human intestinal bacterium stoichiometrically catalyzed the transfer of a sulfate group from phenylsulfate esters to phenolic compounds. Pentachlorophenol, one of the selective inhibitors of phenol sulfoconjugation in mammalian tissues, inhibited both phenol and tyramine sulfation by ASST. Nucleotide triphosphates such as ATP, GTP, UTP and CTP, and pyrophosphate inhibited the ASST activity, whereas Mg2+ and Mn2+ activated the enzyme and prevented its inhibition by ATP and pyrophosphate. Equimolar binding of [alpha-] and [gamma-32P]ATP to the enzyme showed that the enzyme protein was not phosphorylated, but bound ATP. These results suggest that nucleotide triphosphates and divalent cations are important modulators in the control of ASST activity.
来自人类肠道细菌的芳基硫酸酯硫酸转移酶（ASST）以化学计量方式催化硫酸基团从苯硫酸酯转移至酚类化合物。五氯苯酚是哺乳动物组织中酚类硫酸结合的选择性抑制剂之一，它可抑制ASST对苯酚和酪胺的硫酸化作用。三磷酸核苷酸如ATP、GTP、UTP和CTP以及焦磷酸可抑制ASST活性，而Mg2+和Mn2+可激活该酶并防止其被ATP和焦磷酸抑制。[α-]和[γ-32P]ATP与该酶的等摩尔结合表明，酶蛋白未被磷酸化，而是结合了ATP。这些结果表明，三磷酸核苷酸和二价阳离子是控制ASST活性的重要调节剂。
