Molecular cloning, expression, and characterization of novel human SULT1C sulfotransferases that catalyze the sulfonation of N-hydroxy-2-acetylaminofluorene
Molecular cloning, expression, and characterization of novel human SULT1C sulfotransferases that catalyze the sulfonation of N-hydroxy-2-acetylaminofluorene
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DOI：
10.1074/jbc.273.51.33929
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发表时间：
1998-12-18
影响因子：
4.8
通讯作者：
Liu, MC
中科院分区：
文献类型：
--
作者：
Sakakibara, Y;Yanagisawa, K;Liu, MC
经过磺化后，致癌的羟基芳胺（例如N-羟基-2-乙酰氨基芴（N-OH-2AAF））可以进一步活化，在体内形成最终致癌物。先前的研究表明，SULT 1C 1磺基转移酶主要负责大鼠肝脏中N-OH-2AAF的磺化。在本研究中，两个新的人类磺基转移酶的SULT 1C磺基转移酶亚家族的成员序列分析的基础上，已被克隆，表达和表征。比较人SULT 1C磺基转移酶cDNA 1编码的推导的氨基酸序列，发现与大鼠SULT 1C 1磺基转移酶、小鼠SULT 1C 1磺基转移酶和兔SULT 1C磺基转移酶的氨基酸序列具有63.7%、61.6%和85.1%的同一性。相比之下，人SULT 1C磺基转移酶2 cDNA的推导氨基酸序列与人SULT 1C磺基转移酶1、大鼠SULT 1C 1磺基转移酶、小鼠SULT 1C 1磺基转移酶和兔SULT 1C磺基转移酶的氨基酸序列具有62.9%、63.1%、63.1%和62.5%的同一性。重组人SULT 1C磺基转移酶1和2，在大肠杆菌中表达和纯化到近电泳同质性，显示交叉反应与抗血清对大鼠肝SULT 1C 1磺基转移酶，并表现出磺化活性与N-OH-2AAF作为底物。采用北方印迹技术检测这些新型人SULT 1C磺基转移酶的组织特异性表达。这些结果为研究这些新的SULT 1C磺基转移酶在不同人体组织/器官中的功能相关性提供了基础。
Upon sulfonation, carcinogenic hydroxyarylamines such as N-hydroxy-2-acetylaminofluorene (N-OH-2AAF) can be further activated to form ultimate carcinogens in vivo. Previous studies have shown that a SULT1C1 sulfotransferase is primarily responsible for the sulfonation of N-OH-2AAF in rat liver. In the present study, two novel human sulfotransferases shown to be members of the SULT1C sulfotransferase subfamily based on sequence analysis have been cloned, expressed, and characterized. Comparisons of the deduced amino acid sequence encoded by the human SULT1C sulfotransferase cDNA 1 reveal 63.7, 61.6, and 85.1% identity to the amino acid sequences of rat SULT1C1 sulfotransferase, mouse SULT1C1 sulfotransferase, and rabbit SULT1C sulfotransferase. In contrast, the deduced amino acid sequence of the human SULT1C sulfotransferase 2 cDNA displays 62.9, 63.1, 63.1, and 62.5% identity to the amino acid sequences of the human SULT1C sulfotransferase 1, rat SULT1C1 sulfotransferase, mouse SULT1C1 sulfotransferase, and rabbit SULT1C sulfotransferase. Recombinant human SULT1C sulfotransferases 1 and 2, expressed in Escherichia coli and purified to near electrophoretic homogeneity, were shown to cross-react with the antiserum against the rat liver SULT1C1 sulfotransferase and exhibited sulfonating activities with N-OH-2AAF as substrate. Tissue-specific expression of these novel human SULT1C sulfotransferases were examined by employing the Northern blotting technique. The results provide a foundation for the investigation into the functional relevance of these new SULT1C sulfotransferases in different human tissues/organs.