Cocaine Degrading Enzymes From Pest Insects Of Coca Plants

描述(申请人提供)：可卡因是一种强大的精神刺激剂，也是最容易上瘾的滥用药物之一。尽管经过几十年的努力，但还没有针对可卡因成瘾或急性可卡因中毒开发出有效的药物治疗方法。开发抗可卡因治疗的方法主要有两种。1)药效学干预：寻找抑制可卡因与其靶标结合的化合物，但尚未产生有效的药物；2)药代动力学干预：限制或减少可用于作用于其靶蛋白的可卡因数量的策略，如开发可卡因结合抗体和改进的可卡因降解酶。这些抗体可能会被大剂量的可卡因压倒，而每种酶蛋白都可以降解许多可卡因分子。通过特定的和随机的诱变以及计算引导的诱变，在改善相对缓慢的内源性人类酶方面已经取得了重大进展。此外，一种非常活跃的细菌酯酶已经被克隆出来，它比任何其他已知的酶都能更快地分解可卡因。然而，这种酶与人类的酶没有同源性，将这种细菌蛋白本身引入人体可能会引起严重的免疫反应。因此，我们提出了一种利用自然进化力量的策略。我们打算从提取可卡因的古柯植物的主要害虫Eloria noyesi中克隆可卡因降解酶。这些昆虫在它们的食物中摄入了大量的可卡因。摄食幼虫的血液可卡因水平相当低，摄入的大部分可卡因都被降解，这表明存在超快的可卡因降解酶，这种酶已经进化出来，以应对高可卡因饮食。Eloria可卡因降解酶的成功克隆和进一步研究将揭示可卡因超高效水解酶的结构洞察和催化机理，可能为如何修饰和改进人类酶提供新的思路。这些想法与其他实验室的研究相结合，可能会在设计理想的酶方面取得进一步的进展。可卡因降解酶效率的任何显著提高都将对以酶为基础的可卡因滥用治疗的疗效产生重大影响。公共卫生意义：我们建议从提取可卡因的古柯植物E.oca的主要害虫Eloria noyesi中克隆出高效的可卡因降解酶。这些酶的成功克隆和进一步研究可能揭示超高效可卡因降解的机理，从而为进一步改进人类酶提供新的理想，最终可能导致有效和特异的可卡因成瘾和毒性治疗。

DESCRIPTION (provided by applicant): Cocaine is a powerful psycho stimulant and one of the most addictive drugs of abuse. Despite decades of efforts, no effective pharmacological treatments have been developed for cocaine addiction or acute cocaine toxicity. There are two main approaches in developing the anti-cocaine treatments. 1) pharmacodynamic interventions: searching for compounds that inhibit cocaine binding to its targets, which have not resulted in effective drugs yet; 2) pharmacokinetic interventions: strategies to limit or reduce the amount of cocaine available to act on its target proteins, such as the development of cocaine binding antibodies and improved cocaine degrading enzymes. The antibodies could be overwhelmed by large doses of cocaine while each enzyme protein can degrade many cocaine molecules. Significant progress has been made in improving the relative slow endogenous human enzymes by specific and random mutagenesis and by computation guided mutagenesis. In addition, a very active bacterial esterase has been cloned that hydrolyzes cocaine faster than any other known enzymes. However, this enzyme has no homology to the human enzymes and introducing this bacterial protein itself in the human body may cause severe immune responses. Therefore, we propose a strategy that takes advantage of the evolution power of nature. We propose to clone the cocaine degrading enzymes from Eloria Noyesi, the main insect pest of coca plants from which cocaine is extracted. These insects ingest large quantity of cocaine in its diet. The blood cocaine level in the feeding larvae is quite low and most of the ingested cocaine is degraded, suggesting the presence of super fast cocaine-degrading enzymes that have evolved to deal with the high cocaine diet. The successful cloning and additional studies of the cocaine degrading enzymes from Eloria should reveal the structural insight and catalytic mechanism of super efficient cocaine hydrolysis, which may provide novel ideas on how to modify and improve the human enzymes. Such ideas, combined with studies from other labs, may lead to further progress in engineering an ideal enzyme. Any significant improvement in the efficiency of the cocaine-degrading enzyme will make a big impact on the efficacy of an enzyme-based treatment of cocaine abuse. PUBLIC HEALTH RELEVANCE: We propose to clone the super efficient cocaine-degrading enzymes from Eloria Noyesi, the main insect pest of coca plant E. coca from which cocaine is extracted. The successful cloning and further studies of these enzymes may reveal the mechanistic insight of super efficient cocaine hydrolysis and thus provide novel ideals to further improve the human enzymes, which may eventually lead to effective and specific treatments for cocaine addiction and toxicity.