Narrow-Spectrum Drug Targets for Bacillus anthracis

描述(由调查者提供)：本申请是为了响应NIAID对CDC A-C类优先病原体的高优先级生物防御产品的请求。它侧重于对炭疽芽孢杆菌具有选择性活性的化合物的开发，包括最优先的组，A类。本申请的目的是证明炭疽芽孢杆菌特定生物合成途径中潜在的抗微生物靶点的原理，这将允许开发可用于治疗炭疽的化合物。该途径中至少有两种酶代表对标准抗菌剂具有天然抗药性的靶点。因此，针对这些目标的传统药物目前不推荐用于治疗炭疽病。我们假设，这些靶点可以用于新药开发，并且它们可能对化学仓库中已经存在的非传统抗菌剂敏感。因此，该项目的一个目标将是实施最便捷的方法来筛选针对这些酶靶标的现有药物。由于这些酶的同源性很高，我们假设蜡状芽孢杆菌可以代替炭疽芽孢杆菌。这将促进在BSL-2与BSL-3设施中使用机器人系统进行高通量筛选。该方法将使用DNA重组技术结合X射线晶体分子建模来证明炭疽芽孢杆菌基本代谢途径中两个关键酶功能的相似性。重组酶将用于药物筛选试验和结晶，以开发有效的三维模型来确认酶的相似性。如果成功，这一策略将被证明对这一途径中也有高度同源性的其他酶很有用。这一R21应用程序旨在为后续的RO1奠定基础，该RO1将被设计为通过学术研究人员和工业实验室之间的合作产生的早期产品开发来获得针对炭疽芽孢杆菌的窄谱抗生素。

DESCRIPTION (provided by investigator): This application is in response to NIAID's request for high-priority biodefense products specific to CDC Category A-C Priority Pathogens. It focuses on the development of compounds with selective activity against Bacillus anthracis, included in the highest priority group, Category A. The goal of this application is to show proof-of-principal for potential antimicrobial targets in a specific biosynthetic pathway of Bacillus anthracis that will allow for the development of compounds that can be used to treat anthrax. At least two enzymes in this pathway represent targets that are naturally resistant to standard antimicrobial agents. As a result, traditional drugs for these targets are currently not recommended for treatment of anthrax. We hypothesize that these targets are amenable to new drug development and that they may be susceptible to non-traditional antimicrobials that may already exist in chemical repositories. Consequently, one goal of this project will be to implement the most expedient way to screen drugs that are already available against these enzyme targets. Because the degree of homology of these enzymes is so high, we hypothesize that B. cereus can be used in place of Bacillus anthracis. This will facilitate the use of high-throughput screening with a robotics system in a BSL-2 versus a BSL-3 facility. The approach will be to use DNA recombinant technology coupled with X-ray crystallographic molecular modeling to demonstrate proof-of-principal with regard to functional similarities of two key enzymes in an essential metabolic pathway of Bacillus anthracis. Recombinant enzymes will be used in drug-screening assays and for crystallization to develop effective three-dimensional models to confirm enzyme similarities. If successful, this strategy would prove useful for other enzymes in this pathway that also share a high degree of homology. This R21 application is intended to lay the groundwork for a subsequent RO1 that will be designed to attain narrow-spectrum antibiotics for Bacillus anthracis through early product development resulting from collaborations between academic researchers and industrial laboratories.