Enzymic Detoxification for Organophosphate Nerve Agents

描述(申请人提供)：有机磷酸酯和有机磷酸酯是有史以来合成的毒性最大的化合物之一。这些化合物是有毒的，因为它们固有的能力通过乙酰胆碱酯酶的快速和不可逆转的失活来干扰神经传递。有机磷的有毒特性已被用作农业杀虫剂和化学武器。一种细菌磷酸三酯酶已被确定，它可以作为一种催化剂，对广泛的有机磷神经毒剂进行识别、水解和解毒。这项应用的主要目标是设计和表征细菌磷酸三酯酶的修饰形式，这些修饰形式优化了对那些对人类健康构成最严重威胁的有机磷的选择性识别和破坏。将构建合理的突变酶组合文库，并通过新的筛选和选择程序鉴定那些催化能力增强的变异体。细菌磷酸三酯酶氨基酸序列的渐进性变化将直接与X射线衍射法测定的催化常数的增加和活性中心的修饰有关。公共卫生相关性：有机磷神经毒剂的有毒特性对文明社会的健康和福祉构成严重威胁。该项目的主要目标是创造新的催化酶，使其在检测、破坏和解毒广泛的有机磷神经毒剂的能力方面得到优化。

DESCRIPTION (provided by applicant): Organophosphate and organophosphonate esters are among the most toxic compounds that have ever been synthesized. These compounds are toxic because of their inherent ability to interfere with nerve transmission through the rapid and irreversible inactivation of the enzyme acetyl cholinesterase. The toxic properties of the organophosphates have been exploited as agricultural insecticides and as chemical weapons. A bacterial phosphotriesterase enzyme has been identified that can function as a catalyst for the recognition, hydrolysis, and detoxification of a broad spectrum of organophosphate nerve agents. The primary objective of this application is to design and characterize modified forms of the bacterial phosphotriesterase that are optimized for the selective recognition and destruction of those organophosphates that pose the most serious threats to human health. Rational and combinatorial libraries of mutant enzymes will be constructed and those variants with enhanced catalytic proficiency will be identified through novel screening and selection procedures. The progressive changes in the amino acid sequence of the bacterial phosphotriesterase will be directly correlated with the enhancements in the catalytic constants and the modifications within the active site as determined by X-ray diffraction methods. PUBLIC HEALTH RELEVANCE: The toxic properties of the organophosphate nerve agents represent a serious threat to the health and well being of civilized societies. The primary objective of this project is to create novel catalytic enzymes that are optimized in their ability to detect, destroy and detoxify a broad spectrum of organophosphate nerve agents.