Mechanisms and Functions of Human Sulfotransferases

第二相药物代谢酶磺基转移酶(Sults)催化的硫酸盐化在药物代谢过程中起重要作用。 不同激素的调节以及药物和其他外源物质的解毒。硫酸盐化也导致了 前致癌物的生物活化导致的毒性效应。这项研究项目的长期目标是 了解人体排泄物的生物学功能，并调查其与人类健康的相关性 生理和病理条件。这项建议的具体目的如下：1.调查 人硫磺的催化、底物抑制和产物抑制/激活机制。这个 提出的旁路有序机构和相关的替代机构将用动力学 分析、同位素交换、硫酸化活性部位氨基酸残基鉴定和定点定位 诱变。这些信息将对生物转化的预测具有重要意义。 小路。2.研究硫酸盐类药物对人体硫磺催化活性的影响。抑制力 临床上重要的药物硫酸盐对人硫磺的催化活性的激活作用将是 调查过了。原核表达和纯化的人硫磺、人肠道胞浆和人Hep G2 而Caco-2细胞将用于这些研究。临床药物对人体血脑屏障活动的影响 可能会干扰激素调节和异物解毒的正常生物学功能。3.至 确定人类SULT1E1的氧化调节机制。人SULT1E1在细胞内的氧化调节 Hep G2和Caco-2细胞及纯化的人SULT1E1的氧化还原硫醇调节机制 采用酶分析、Western印迹、RT-PCR、氨基酸修饰、定点检测等方法进行研究 诱变、动力学分析、晶体结构分析和计算机模拟方法。了解以下内容 某些人体sulth的氧化调节对于理解sulu功能的能力很重要。 在生理和病理条件下。 这项提议研究的是人类的。这些研究将对理解结果具有重要意义 生物功能包括激素调节、药物代谢、异物解毒和 致癌原生物活化。这些知识将对了解药物副作用、药物-药物 相互作用，药物开发，以及结果在癌症预防和病因中所起的潜在作用。

Phase II drug metabolizing enzymes sulfotransferases (SULTs) catalyzed sulfation is important in the regulation of different hormones and the detoxification of drugs and other xenobiotics. Sulfation also leads to bioactivation of procarcinogens leading to toxic effect. The long-term goal of this research project is to understand human SULT biological functions and to investigate their relevance to human health under physiological and pathological conditions. Specific aims in this proposal are as follows: 1. To Investigate Mechanisms of Catalysis, Substrate Inhibition, and Product Inhibition/Activation of Human SULTs. The proposed bypass ordered mechanism and related alternative mechanisms will be investigated using kinetic analysis, isotope exchange, sulfated active site amino acid residue identification, and site-directed mutagenesis. The information will have important implications for the prediction of biotransformation pathways. 2. To Investigate the Effect of Sulfated Drugs on Human SULT Catalytic Activities. The inhibition and activation effect of clinically important drug sulfates on catalytic activities of human SULTs will be investigated. E. coli expressed and purified human SULTs; human intestinal cytosols; and human Hep G2 and Caco-2 cells will be used for these investigations. The effect of clinical drugs on human SULT activities may interfere SULT normal biological functions in hormone regulation and xenobiotic detoxification. 3. To Define Oxidative Regulation Mechanisms of Human SULT1E1. Oxidative regulation of human SULT1E1 in Hep G2 and Caco-2 cells and redox thiol regulation mechanisms of purified human SULT1E1 will be investigated using enzyme assay, Western blot, RT-PCR, amino acid modification, site-directed mutagenesis, kinetic analysis, crystal structure analysis, and computer modeling methods. Knowledge on oxidative regulation of certain human SULT is important in understanding the ability of SULT functioning under physiological and pathological conditions. This proposal studies human SULTs. These studies will be significant in understanding SULT biological functions including hormone regulation, drug metabolism, xenobiotic detoxification and procarcinogen bioactivation. The knowledge will be important in understanding drug side effect, drug-drug interaction, drug development, and the potential roles SULTs play in cancer prevention and causation.