Novel Antibiotic Targets: Mechanistic Studies on Dinuclear Metallohydrolases

新的抗生素靶点：双核金属水解酶的机制研究

• 批准号: 0652981
• 负责人: Richard Holz
• 金额: --
• 依托单位: Loyola University of Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0652981&HistoricalAwards=false
• 关键词: Novel; Antibiotic; Targets; Mechanistic; Studies

This award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports research by Professor Richard C. Holz at the Loyala University of Chicago to develop an understanding of hydrolytic reactions catalyzed by metallohydrolases that contain dinuclear active sites. These enzymes catalyze diverse reactions such as the degradation of DNA, RNA, phospholipids, and polypeptides. The research will explore why some hydrolases utilize a mononuclear center while others function with either a mononuclear or dinuclear active site, and still others require two metal ions to catalyze the same chemical reaction. These systems use different metal ion Lewis acidities in discrete dinuclear sites to i) bind and position substrate, ii) bind and activate a water molecule to yield an active site hydroxide nucleophile, and/or iii) stabilize the transition state of the hydrolytic reaction. Structurally detailed catalytic mechanisms will be developed for the leucine aminopeptidase from Vibrio (Aeromonas) proteolyticus (AAP), the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) from H. influenzae, and the argE-encoded N-acetyl-L-ornithine deacetylase (ArgE) E. coli. The experimental approach incorporates biochemical, spectroscopic, X-ray crystallographic methods.and site directed mutants of catalytically important amino acid residues, and small molecule inhibitors. The specific aims are: i) Which metal ion in AAP functions as the catalytic metal ion?, ii) What are the catalytic roles of active site residues that reside in the second coordination sphere?, iii) What residues in the active site of DapE and ArgE play catalytically important roles?, iv) How do substrate- and transition-state analog inhibitors interact with DapE and ArgE?, v) Synthesize novel inhibitors of DapE and ArgE that may function as antibacterial agents. This research addresses the mechanism of action of dinuclear metalloproteases which play a central role in several disease states including stroke, diabetes, cancer, HIV, bacterial infections, and neuropsychiatric disorders associated with the dysregulation of glutamatergic neurotransmission, such as schizophrenia, seizure disorders, and amyotrophic lateral sclerosis (ALS). This knowledge may lead to the development of coordination complexes that are capable of catalyzing industrially important hydrolytic reactions. In addition, these mechanistic data will aid in the design of small molecules that function as new anti-bacterial agents.

该奖项在芝加哥Loyala C. Holz教授的研究中支持了无机，生物有机和有机金属化学计划，以发展对含有二核活性场所的金属水解酶催化的水解反应的理解。这些酶催化了多种反应，例如DNA，RNA，磷脂和多肽的降解。这项研究将探讨为什么一些水解酶使用单核中心，而另一些水解酶则在单核或二核活性位点发挥作用，而另一些则需要两个金属离子来催化相同的化学反应。 这些系统在离散的双核位点中使用不同的金属离子刘易斯酸度与i）结合并定位底物，ii）结合并激活水分子以产生活性位点氢氧核定菌和/或iii）稳定水解反应的过渡状态。将为纤维氨酸氨基肽酶（AEPOMONAS）蛋白水解酶（AAP），DAPE代码的N-核酸-L，L-二氨基二核酸二酸去甲酸去甲酸氨基糖基酶（DAPE）开发为亮氨酸氨基肽酶（AAP）开发的结构详细的催化机制。大肠杆菌。 实验方法结合了生化，光谱，X射线晶体学方法。以及位点的定向突变体的突变体和小分子抑制剂。 具体目的是：i）AAP中的哪种金属离子充当催化金属离子？ DAPE和ARGE的抑制剂可能充当抗菌剂。这项研究探讨了双核金属蛋白酶的作用机制，在包括中风，糖尿病，癌症，HIV，细菌感染和神经精神疾病在内的几种疾病状态中起着核心作用，与谷氨酸性神经传递失调有关 这些知识可能会导致能够催化工业上重要的水解反应的协调复合物的发展。此外，这些机械数据将有助于设计作为新的抗细菌剂的小分子。