HUMAN CYTOSOLIC SULFOTRANSFERASES

这个项目的总体目标是研究生物化学， 人胞浆的异质性及其分子生物学 磺基转移酶(STS)和理解硫酸盐化在植物生长中的作用 药物、外源物质和内源性底物在人体内的代谢。这个 一等奖涉及苯酚磺基转移酶的研究 (PST)；然而，在这些研究中，我们 还鉴定、纯化和克隆了主要的类固醇/胆汁酸ST 人肝，脱氢表雄酮(DHEA)St.DHEA是 类固醇ST是STS的家族，与PSTs关系不密切，但也与PSTs 在类固醇和药物代谢中起着重要作用。因此， 该项目的具体目标被扩大到包括对 所有人类胞浆STS的蛋白质化学和分子生物学。我们 相信这些基本的生化信息将改善我们的 了解人体药物代谢，为药物研究提供信息 设计和治疗，以及增加我们对 细胞生理学中的硫酸盐化。 硫酸盐化是生物转化的主要途径之一。 排泄药物和内源性化合物，如类固醇和 儿茶酚胺。硫酸盐结合一般会导致减少 化合物的生物活性及其溶解度的增加； 然而，硫酸盐化可能参与化合物的生物活性以 诱变剂和致癌物，或具有药理活性的形式。多数 动物物种似乎有多种形式的肝脏胞浆STS 然而，胞浆ST只有三种不同的主要形式 已确认身份。这些酶的特性和研究将是 对了解它们的生物和药物代谢功能很重要。 其他形式的ST的鉴定和特征也将是 有必要扩大我们对硫酸盐化和硫化的功能的了解 STS的异质性。 本项目将重点研究人体肝脏中苯酚ST(PST)的两种形式 人肝细胞浆、M-PST和P-PST以及主要类固醇/胆汁酸ST 肾上腺胞浆，DHEA-ST。我们将利用这些知识和 重要开发工具获一等奖。这样做的具体目的是 建议是：1)表征人类肝脏的分子结构 PSTs和DHEA-ST；2)研究DHEA-ST在人体内的定位 组织；3)研究细菌的基因组结构和异质性 PST在人肝脏中的等位基因形式；4)研究PST的能力 和DHEA-ST偶联药物和生物活性诱变剂 5)鉴定、提纯和克隆人雌激素 磺基转移酶。

The overall goal of this project is to investigate the biochemistry, heterogeneity and molecular biology of the human cytosolic sulfotransferases (STs) and to understand the role of sulfation in the metabolism of drugs, xenobiotics and endogenous substrates in humans. The First Award involved the investigation of the phenol sulfotransferases (PST) in human platelet and liver cytosol; however, during these studies we also identified, purified and cloned the major steroid/bile acid ST in human liver, dehydroepiandrosterone (DHEA) ST. DHEA is a member of the steroid ST family of STs and is not closely related to the PSTs but also has important roles in steroid and drug metabolism. Therefore, the Specific Aims of this project are expanded to include the investigation of the protein chemistry and molecular biology of all human cytosolic STs. We believe that this fundamental biochemical information will improve our understanding of human drug metabolism and provide information for drug design and therapy, as well as increase our knowledge of the functions of sulfation in cellular physiology. Sulfation is one of the major pathways for the biotransformation and excretion of drugs and endogenous compounds, such as steroids and catecholamines. Sulfate conjugation generally results in a decrease in the biological activity of a compound and an increase in its solubility; however, sulfation may be involved in the bioactivation of compounds to mutagens and carcinogens, or to pharmacologically active forms. Most animal species appear to have multiple forms of hepatic cytosolic STs whereas, only three distinct major forms of cytosolic ST have been identified. Characterization and investigation of these enzymes will be important to understand their biological and drug metabolism functions. Identification and characterization of other forms of ST will also be necessary to enlarge our understanding of the functions of sulfation and the heterogeneity of STs. This project will focus on the two forms of phenol ST (PST) in human liver cytosol, M-PST and P-PST, and the major steroid/bile acid ST in human liver and adrenal cytosol, DHEA-ST. We will capitilize on the knowledge and important tools developed by the First Award. The Specific Aims of this proposal are to: 1) characterize the molecular structure of the human liver PSTs and DHEA-ST; 2) investigate the localization of DHEA-ST in human tissues; 3) investigate the genomic organization and heterogeneity of allelic forms of PST in human liver; 4) investigate the ability of the PSTs and DHEA-ST to conjugate drugs and bioactive mutagens following expression in cultured cells; and 5) identify, purify , and clone human estrogen sulfotransferase.