Study of tissue-specific dihydrodiol dehydrogenase

组织特异性二氢二醇脱氢酶的研究

基本信息

批准号：
11672175
负责人：
HARA Akira
金额：
$ 2.3万
依托单位：
Gifu Pharmaceutical University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

Dihydrodiol dehydrogenase (DD, EC 1.3.1.20), which catalyzes the NADP-dependent oxidation of trans-dihydrodiols of aromatic hydrocarbons, has been shown to be involved in cytotoxicity of the aromatic hydrocarbons. The enzyme exits in multiple forms in mammalian tissues. Of the multiple forms dimeric DD is tissue-specifically expressed, but its structure and physiological function have not been elucidated. This study was performed to elucidate the structure of dimeric DD, its relationship to the function and possible clinical significance. The results obtained are summarized.1. Dimeric DD in monkey kidney, pig and dog liver was demonstrated to be identical with NADP-dependent D-xylose dehydrogenase (EC 1.1.1.179).2. The protein sequencing and/or cDNA cloning primary structures of dimeric DDs in rabbit lens, human intestine and the above animal tissues revealed that the enzymes constitute a new protein family with prokaryotic proteins including glucose-fructose oxidoreductase.3. The site … More -directed mutagenesis on the monkey dimeric DD suggested that Tyr-180 is a catalytic residue, Lys-97 and His-79 function both coenzyme binding and chemical steps of the reaction, and Tyr-71 and His-76 are involved in coenzyme binding. In addition, Trp-125, Asp-176 and Trp-254 were suggested to be responsible for substrate binding, and of the three residues Asp-176 is thought to be important for the adaptation of the alcohol substrate in to the binding site. The crystallographic study is now in progress.4. Dimeric DD was inhibited by several drugs such as nonsteroidal anti-inflammatory agents, of which the potent inhibitors commonly had 4-hydroxyphenylketone structure. The enzyme's mRNA, although it did not detected in normal human kidney, was detected in one of five renal cancer specimen. The variant gene with respect to exon 4 region was not detected, and such a study for other exon regions will be continued to find clinical significance.5. During the course of cloning of the genomic gene for dimeric, I noticed that the gene is included in a working draft sequence of chromosome 19. The 5'-noncoding region of this gene contains various putative binding sites for transcription factors.6. The structural and functional aspects obtained in this study was presented in 10^<th> International Symposium on Enzymology and Molecular Biology of Carbonyl Metabolism (New Mixico, U.S.A., July, 2000). Less

二氢二醇脱氢酶(DD，EC 1.3.1.20)催化芳香烃反式二氢二醇的NADP依赖性氧化，已被证明参与芳香烃的细胞毒性，该酶以多种形式存在于哺乳动物组织中。多种形式的二聚体DD是组织特异性表达的，但其结构和生理功能尚未阐明。阐明了二聚体DD的结构、其与功能的关系以及可能的临床意义。结果如下：1．在猴肾、猪和狗肝脏中获得的二聚体DD与NADP依赖性D-木糖脱氢酶相同。 EC 1.1.1.179).2. 兔晶状体、人肠和上述动物组织中二聚体 DD 的蛋白质测序和/或 cDNA 克隆表明，这些酶构成了一种新的酶。包括葡萄糖-果糖氧化还原酶在内的原核蛋白家族。猴二聚体 DD 上的定点诱变表明 Tyr-180 是催化残基，Lys-97 和 His-79 兼具辅酶结合和化学步骤。该反应中，Tyr-71 和 His-76 参与辅酶结合，此外，Trp-125、Asp-176 和Trp-254 被认为负责底物结合，并且三个残基中的 Asp-176 被认为对于醇底物适应结合位点很重要。二聚体 DD 的晶体学研究正在进行中。该酶被多种药物抑制，例如非甾体类抗炎药，其中有效的抑制剂通常具有4-羟基苯基酮结构。该酶的mRNA虽然在正常人肾脏中未检测到，但在其中一种中检测到。 5个肾癌标本中，未检测到外显子4区域的变异基因，将继续对其他外显子区域进行这样的研究以寻找临床意义。5．在克隆二聚体基因组基因的过程中，我注意到。该基因包含在 19 号染色体的工作草案序列中。该基因的 5'-非编码区包含转录因子的各种推定结合位点。6。本研究中获得的结构和功能方面在第 10^<th 中提出。 > 国际研讨会关于羰基代谢的酶学和分子生物学（New Mixico，美国，2000 年 7 月）。