MECHANISMS OF PYRIDOXAL-5'-PHOSPHATE DEPENDENT ENZYMES

吡哆醛-5-磷酸依赖性酶的机制

• 批准号: 6519347
• 负责人: ROBERT STEPHEN PHILLIPS
• 金额: $ 19.11万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-09-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6519347
• 关键词: antibacterial agents; bacterial proteins; biochemical evolution; carbon carbon hydrolase; carbon carbon lyase; drug design /synthesis /production; enzyme activity; enzyme inhibitors; enzyme mechanism; enzyme structure; kynurenine; peptide chemical synthesis; protein sequence; pyridoxal phosphate; site directed mutagenesis; spectrometry; stop flow technique; transaminases; tryptophan; tryptophan synthase; tyrosine

DESCRIPTION (adapted from applicant's abstract): The investigators are studying the mechanism of pyridoxal-5'-phosphate-dependent enzymes that break or form carbon-carbon bonds. These enzymes include tryptophan indole-lyase, tyrosine phenol-lyase, tryptophan synthase, bacterial and human kynureninases, and aspartate beta-decarboxylase. They are evaluating the reaction mechanism of tyrosine phenol-lyase and tryptophan indole-lyase. The investigators are determining the roles of specific amino acids in catalysis and reaction specificity by both site-directed mutagenesis and by synthesis of a C-terminal peptide containing unnatural amino acids. The investigators are probing the mechanism of the reaction of these enzymes by various kinetic techniques, including rapid scanning stopped flow spectrophotometry and rapid chemical quench. They will design, synthesize, and evaluate novel inhibitors of tryptophan indole-lyase that may be useful in the treatment of Haemophilus influenzae meningitis. The potent competitive inhibitors of kynureninase that they are designing and synthesizing, based on their studies of the bacterial enzyme, have been patented and are undergoing studies to evaluate their potential in the treatment of neurological disorders such as stroke. The investigators will determine and compare the structure and reaction mechanism of bacterial and human kynureninases as well as aspartate beta-decarboxylase. More information on the structure and mechanism of kynureninases mat lead to the design of other more selective and potent inhibitors. The central role of pyridoxal-5'phosphate-dependent enzymes in the metabolism of amino acids and amines and in the biosynthesis of important bioactive metabolites, makes them attractive targets for the design of mechanism-based inhibitors which may be useful for drugs. Thus the results of this research are likely to make a significant contribution to the goal of improving health care for Americans in the future.

描述（根据申请人的摘要改编）：研究人员正在研究 破裂或形成的吡idox-5'-磷酸依赖性酶的机制 碳碳键。这些酶包括色氨酸吲哚 - 酪氨酸 酚 - 洛碱，色氨酸合酶，细菌和人kynureninase，以及 天冬氨酸β-二羧基酶。他们正在评估 酪氨酸酚 - 酯和色氨酸吲哚 - 裂解酶。调查人员是 确定特异性氨基酸在催化和反应中的作用 位置定向诱变和C末端的特异性 含有非天然氨基酸的肽。调查人员正在探测 这些酶通过各种动力学技术的反应机制， 包括快速扫描停止流量分光光度法和快速化学 淬火。他们将设计，合成和评估新颖的抑制剂 色氨酸吲哚 - 可能在治疗嗜血杆菌的治疗 流感脑膜炎。有效的伴抗素氨酸酶的竞争抑制剂 他们根据细菌的研究设计和合成 酶，已获得专利，正在接受研究以评估其 治疗神经系统疾病（例如中风）的潜力。这 研究人员将确定并比较结构和反应机理 细菌和人kynureninase以及天冬氨酸β-二羧化酶的含量。 有关kynureninases Mat的结构和机制的更多信息导致 其他更具选择性和有效抑制剂的设计。中心角色 氨基酸代谢和 胺和重要生物活性代谢产物的生物合成使它们成为 可能是基于机制的抑制剂设计的有吸引力的目标 对药物有用。因此，这项研究的结果可能使 为改善美国人的医疗保健的目标做出了重大贡献 未来。