THEORETICAL STUDY--METALLOENZYME STRUCTURE AND FUNCTION

本研究的目的是发展和应用理论 模拟技术来研究蛋白质的性质和能量学， 底物和蛋白质-抑制剂相互作用，非催化的机制， 液相反应和酶催化反应。 对这些现象的理论见解将对 人体健康 我们对现有抑制剂的了解的增加， 新酶抑制剂的设计将对改善 人类的状况 我们对蛋白质结构的了解的增加， 功能将对生物技术产生重大影响，因为它将允许 用于从头设计新的蛋白质， 催化性能 为了解决这些问题，我们决定专注于一种蛋白质和主题 严格的理论审查 我们的模型是锌金属酶 人碳酸酐酶II（HCAII）具有重要的生物医学意义 重要性，因为它在涉及CO2的生理过程中的作用， 因为这种酶的抑制剂是用于治疗 青光眼 我们的第一个目标将是开发必要的分子 催化所需的机械势函数参数 锌离子在这种酶，其次是发展的耦合量子 机械/分子力学模拟包，将用于 研究二氧化碳的非催化和催化反应。 为了 确定哪些结构特征对酶催化重要， 首先有助于理解未催化的气相和溶液相 反应. 因此，我们将开展理论研究， CO2与氢氧化物的非催化溶液和气相反应， 将允许深入了解HCAII如何催化这一反应。 的 其余的拟议研究包括对解决方案的调查 和CO2与水的气相反应，这是在 血液的缓冲，HCAII催化机理的研究， 研究HCAII-底物相互作用，并通过审查已知的 和潜在的新HCAII抑制剂。

The goal of the proposed research is to develop and apply theoretical simulation techniques to study the nature and energetics of protein- substrate and protein-inhibitor interactions, the mechanisms of uncatalyzed solution phase reactions, and enzymatically catalyzed reactions. Theoretical insights into these phenomenon will have a major impact on human health. The increase in our understanding of existing inhibitors and the design of new enzyme inhibitors will have a major impact on improving the human condition. An increase in our knowledge of protein structure and function will have a major impact on biotechnology, because it will allow for the ab initio design of new proteins with increased or more selective catalytic properties. To address these issues we have decided to focus on one protein and subject to intense theoretical scrutiny. Our model will be the zinc metalloenzyme human carbonic anhydrase II (HCAII), which is of great biomedical importance because of its role in physiological processes involving CO2, and because inhibitors of this enzyme are drugs used in the treatment of glaucoma. Our first goal will be to develop the necessary molecular mechanical potential function parameters for the catalytically necessary zinc ion in this enzyme, followed by the development of a coupled quantum mechanical/molecular mechanical simulation package, which will be used to study both the uncatalyzed and catalyzed reactions of CO2. In order to identify what structural features are important for enzymatic catalysis it is first useful to understand the uncatalyzed gas-phase and solution phase reactions. Thus, we will initiate theoretical studies to examine the uncatalyzed solution and gas-phase reaction of CO2 with hydroxide, which will allow for insights into how HCAII catalyzes this reaction. The remainder of the proposed studies include investigations on the solution and gas-phase reaction of CO2 with water, which is an important reaction in the buffering of blood, studies on the catalytic mechanism of HCAII, studies on HCAII-substrate interactions, and a through scrutiny of known and potentially new HCAII inhibitors.