Identification and characterization of two novel cytosolic sulfotransferases, SULT1 ST7 and SULT1 ST8, from zebrafish
Identification and characterization of two novel cytosolic sulfotransferases, SULT1 ST7 and SULT1 ST8, from zebrafish
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DOI：
10.1016/j.aquatox.2008.06.005
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发表时间：
2008-08-29
影响因子：
4.5
通讯作者：
Liu, Ming-Cheh
中科院分区：
文献类型：
--
作者：
Liu, Tzu-An;Bhuiyan, Shakhawat;Liu, Ming-Cheh
胞液硫转移酶(Sults)是一个11相解毒酶家族，参与了对潜在有害外源物质的保护以及内源化合物的调节和动态平衡。与人类和啮齿动物相比，斑马鱼是研究硫磺在环境污染物(包括环境雌激素)解毒中作用的极好模型。通过搜索表达序列标签数据库，鉴定了两个编码可能结果的斑马鱼cDNAs。序列分析表明，这两个可能的斑马鱼结果属于SULT1基因家族。利用pGEX-2TK谷胱甘肽-S转移酶(GST)基因融合系统表达并纯化了这两个新斑马鱼SULT1ST7和SULT1ST8的重组形式。纯化的GST融合蛋白SULT1 ST7和SULT1 ST8在作为底物的各种内源和异源化合物中，对环境雌激素，特别是羟基多氯联苯(PCBS)具有很强的硫化活性。PH依赖性实验表明，SULT1 ST7和SULT1 ST8的最适pH分别为6.5和8.0。测定了这两种酶催化儿茶素、绿原酸和3-氯-4-联苯酚硫化反应的动力学参数。发育表达实验表明，SULT1 ST7和SULT1 ST8在胚胎发育和整个幼虫阶段到成熟期的表达模式不同。(C)2008爱思唯尔B.V.保留所有权利。
Cytosolic sulfotransferases (SULTs) constitute a family of Phase 11 detoxification enzymes that are involved in the protection against potentially harmful xenobiotics as well as the regulation and homeostasis of endogenous compounds. Compared with humans and rodents, the zebrafish serves as an excellent model for studying the role of SULTs in the detoxification of environmental pollutants including environmental estrogens. By searching the expressed sequence tag database, two zebrafish cDNAs encoding putative SULTs were identified. Sequence analysis indicated that these two putative zebrafish SULTs belong to the SULT1 gene family. The recombinant form of these two novel zebrafish SULTs, designated SULT1 ST7 and SULT1 ST8, were expressed using the pGEX-2TK glutathione S-transferase (GST) gene fusion system and purified from transformed BL21 (DE3) cells. Purified GST-fusion protein form of SULT1 ST7 and SULT1 ST8 exhibited strong sulfating activities toward environmental estrogens, particularly hydroxylated polychlorinated biphenyls (PCBs), among various endogenous and xenobiotic compounds tested as substrates. pH-dependence experiments showed that SULT1 ST7 and SULT1 ST8 displayed pH optima at 6.5 and 8.0, respectively. Kinetic parameters of the two enzymes in catalyzing the sulfation of catechin and chlorogenic acid as well as 3-chloro-4-biphenylol were determined. Developmental expression experiments revealed distinct patterns of expression of SULT1 ST7 and SULT1 ST8 during embryonic development and throughout the larval stage onto maturity. (C) 2008 Elsevier B.V. All rights reserved.