Characterizing and engineering toluene o-xylene monooxygenase for the synthesis of common drug metabolites

项目摘要/摘要 当药物在体内代谢时，它们的代谢物代表了人类所面对的新的化学实体。 暴露了。因此，研究药物代谢物的毒性和生物活性是至关重要的。 用于开发安全、有效的药物。事实上，药代动力学研究是 向美国食品和药物管理局提交的调查性新药申请。作为这些研究的一部分， 然而，在体外，特别是在体内，需要大量的纯代谢物来表征它们。 药物代谢物的化学合成在产率、选择性方面存在问题，并且可能是一项主要成本- 临床前研究的推动者。直接酶法合成药物代谢物是一种很有吸引力的替代方法。虽然 在人类肝脏中发现的P450单加氧酶一直是药物代谢的焦点。 生物催化剂，仍然存在许多挑战，如生物催化活性低，药物底物专一性有限，以及 产品范围。对交替酶或生物催化剂的研究可能会导致代谢产物的多样化 产品光谱，并为高效代谢物生产开辟了新的视野。由于其出色的化学性质， 底物范围广，催化活性可延展，我们建议研究生物催化剂甲苯邻二甲苯 假单胞菌的单加氧酶(Tomo)OX1作为一种药物代谢酶。使用蛋白质工程 在技术方面，我们计划创造具有增强的药物氧化活性和微调的特异性的Tomo变体。 使用蛋白质工程，我们之前创建了几个Tomo的变体，用于绿色化学和 生物修复应用。Tomo及其工程变体在药物合成中的应用前景 代谢物提供了一种新的令人兴奋的方法。我们的长期目标是提高Tomo Even的多功能性 进一步探索和扩大其用于药物开发和制药生产的底物库。 本项目的具体目标是用6种不同的方法表征野生型Tomo的药物氧化活性 药物底物和类药物候选物，包括苯胺、乙酰苯胺、安非他酮、噻氯匹定、扑尔敏 和奥美拉唑(Aim 1)，利用蛋白质工程技术构建Tomo变异体文库，并进行进一步筛选 改进(目标2)，以及药物氧化活性的阳性Tomo变体的序列、模型和特征 (目标3)。

Project Summary/Abstract As drugs are metabolized in the body, their metabolites represent new chemical entities to which humans are exposed. Thus, investigating the toxicities and characterizing biological activities of drug metabolites is crucial for the development of safe, effective drugs. In fact, pharmacokinetic studies are critical components of investigational new drug applications to the US Food and Drug Administration. As a part of these studies, however, large quantities of pure metabolites are needed to characterize them in vitro and, especially in vivo. The chemical synthesis of drug metabolites is problematic in terms of yield, selectivity, and can be a major cost- driver in preclinical studies. Direct enzymatic synthesis of drug metabolites is an attractive alternative. Although P450 monooxygenase enzymes, found in human liver, have been in the spot light as drug metabolizing biocatalysts, many challenges still remain such as low biocatalytic activity, limited drug substrate specificity and product range. The investigation of alternate enzymes or biocatalysts may lead to a diversified metabolites product spectra and open up new horizons for efficient metabolite production. Due to its excellent chemistry, wide substrate range, and malleable catalytic activity, we propose to investigate the biocatalyst toluene o-xylene monooxygenase (ToMO) of Pseudomonas sp. OX1 as a drug metabolizing enzyme. Using protein engineering techniques, we plan to create ToMO variants with enhanced drug oxidation activity and fine-tuned specificity. Using protein engineering, we previously created several variants of ToMO for green chemistry and bioremediation applications. The prospect of using ToMO and its engineered variants for the synthesis of drug metabolites presents a new and exciting approach. Our long-term goal is to improve the versatility of ToMO even further by exploring and expanding its substrate repertoire for drug development and pharmaceutical production. The specific aims of this project are to characterize wild-type ToMO for drug oxidation activity with 6 different drug substrates and drug-like candidates including aniline, acetanilide, bupropion, ticlopidine, chlorphenamine, and omeprazole (Aim 1), construct ToMO variant libraries using protein engineering and screen for further improvements (Aim 2), and sequence, model, and characterize positive ToMO variants for drug oxidation activity (Aim 3).