DESIGN AND SYNTHESIS OF INHIBITORS FOR GLYCOENZYMES

糖酶抑制剂的设计与合成

• 批准号: 6285064
• 负责人: YOSHITAKA ICHIKAWA
• 金额: $ 26.4万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-01 至 2002-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6285064
• 关键词: N acetylglucosamine; N acetylglucosaminidase; N glycosidase; X ray crystallography; carbohydrate metabolism; chemical synthesis; enzyme inhibitors; enzyme mechanism; glycosylation

DESCRIPTION: (Principal Investigator's Abstract) The long-term goal of this research is to design, synthesize and evaluate specific inhibitors of enzymes involved in carbohydrate metabolism, as a means of elucidating the roles played by these enzymes in biologically and clinically significant processes. Data from this laboratory has already demonstrated that l-N-iminosugars are highly potent and specific inhibitors of beta-glycosidases and that its conjugate with a UDP analog is a specific and potent inhibitor of alpha-galactosyltransferase. This competing continuation will focus on two biologically important carbohydrate metabolic processes: Aim 1. To study the biological role of O-GlcNAc. 0-Linked beta-N-acetylglucosamine (0-GlcNAc) is found in many proteins, and its on-and-off glycosylation is thought to regulate the functions of these proteins. Since glycosylation and phosphorylation often (occur at the same sites in a protein, use of inhibitors of the enzyme that regulate the glycosylation offer a viable alternative to site-directed mutagenesis as an approach to analyzing the role of glycosylation. The biological role of 0-GlcNAc will be elucidated by designing and using specific inhibitors to characterize 0-GIcNAc-specific N-acetylglucosaminidase (0-GlcNAc'ase), the enzyme which removes 0-GlcNAc from proteins. The proposed inhibitors include nagastatin analogs and 1-thio-GIcNAc (S-GlcNAc) derivatives and their peptide-conjugates; one potent and specific inhibitor, a S-GlcNAc derivative has already been synthesized. The most promising inhibitors will be used in several biological systems, including cancer cells, in which 0-GlcNAc is thought to play a key role. Aim 2. To study the reaction mechanism of DNA N glycosylases. DNA base-excision enzymes (N-glycosylases) play a central role in maintaining genetic integrity; however, their reaction mechanisms are still undetermined. This laboratory has recently solved an x-ray crystal structure of the complex of 1-azaribose-containing DNA and one such glycosylase, 3-methyladenine DNA glycosylase (AlkA), and has identified a potential role for the conserved Asp residue in its catalytic process. As a continuation of this work, more specific molecular probes will be developed as a means of gaining additional insight into the mechanisms for the base flipping and N-glycosidic bond-cleaving reactions of other members of this class of enzymes. Given the potential specificity and potency of the proposed inhibitors, these reagents are expected to contribute not only to the study of the biological roles of such important carbohydrate-metabolizing enzymes but also to the development of inhibitor-based drugs with a wide range of clinical applications.

描述：（主要研究者的摘要） 研究是设计，合成和评估酶的特定抑制剂 参与碳水化合物代谢，以阐明扮演的角色 通过这些酶在生物学和临床意义的过程中。数据 该实验室已经证明了L-N-iminosugars高度 β-糖苷酶的有效和特定抑制剂，并与之共轭 UDP类似物是α-半乳糖基转移酶的特定且有效的抑制剂。 这种竞争的延续将集中于两个在生物学上重要的 碳水化合物代谢过程：目的1。研究的生物学作用 O-GlcNAC。在许多人中发现了0连接的β-N-乙酰葡萄糖胺（0-GLCNAC） 蛋白质及其在糖基化上被认为可以调节功能 这些蛋白质。由于糖基化和磷酸化经常发生（发生在 蛋白质中的相同位点，使用调节酶的抑制剂 糖基化为位置定向诱变提供了可行的替代品 分析糖基化作用的方法。生物学的作用 通过设计和使用特定抑制剂来阐明0-GLCNAC 表征0-GICNAC特异性N-乙酰葡萄糖氨基酶（0-GLCNAC'ASE）， 从蛋白质中去除0-GLCNAC的酶。提出的抑制剂包括 nagastatin类似物和1- thio-gicnac（S-GLCNAC）衍生物及其衍生物 肽偶联；一种有效的特异性抑制剂，一种S-GLCNAC衍生物 已经合成了。最有希望的抑制剂将用于 几个生物系统，包括癌细胞，其中0-GLCNAC为 被认为扮演着关键角色。目的2。研究DNA N的反应机理 糖基酶。 DNA碱基化酶（N-糖基酶）在中心作用 保持遗传完整性；但是，它们的反应机制仍然是 不确定。该实验室最近解决了一个X射线晶体结构 含1-亚瓜糖的DNA和一种这样的糖基化酶的复合物， 3-甲基杜氏素DNA糖基化酶（ALKA），并确定了对 保守的ASP残基在其催化过程中。作为延续 工作，将开发更具体的分子探针作为获得的一种手段 对基础翻转和N-糖苷机制的更多洞察力 该类酶的其他成员的键切割反应。鉴于 这些试剂的潜在特异性和效力 期望不仅为研究的生物学作用做出贡献 如此重要的碳水化合物 - 代谢酶 具有广泛临床应用的基于抑制剂的药物。