Structural Robustness of Ribosome Functional Centers

 描述（申请人提供）：项目概述抗生素耐药微生物再次成为全球人类健康的主要威胁。曾经在对抗致命病原体传播方面至关重要的药物已经变得无效。开发新的抗菌剂来解决这一危机将需要详细了解抗生素耐药性的潜在机制，包括抗生素靶点突变引起的耐药性的结构基础。最重要的抗生素靶标是核糖体，核糖体是蛋白质合成的通用位点，并且已经在许多物种中鉴定出耐药性突变。通过强有力的合作努力，该提案利用了嗜热栖热菌核糖体的遗传学和X射线晶体学的现状，以解决抗生素耐药性的基本方面。该提案的目的是：（1）确定多个抗生素耐药突变之间表型相互作用的结构基础，这些突变可能在连续暴露于多种抗生素挑战后出现;（2）监测继发突变的演变，以补偿有害的抗生素耐药突变的适应度成本。这些目标旨在为抗生素耐药性机制提供基本见解，研究结果将适用于针对耐药性病原体的药物的合理设计。 实现这些目标将涉及遗传学和X射线晶体学的创新融合，以确定突变核糖体的结构。细菌T.嗜热菌特别适合作为模型系统，这是由于其对遗传操作的适应性和其核糖体对结晶的适合性。我们的建议基于以下坚实的基础：（1）在遗传学和X射线晶体学方面的丰富经验，包括实现拟议目标所需技能的可靠记录;（2）广泛的初步结果，包括许多抗肿瘤核糖体的结构测定;（3）在蛋白质合成领域和抗肿瘤方面的广泛工作知识，如长期出版记录所示;（4）两个PI之间的良好合作关系。该提案目标的实现将为抗生素耐药性机制提供基本见解，这将对尚未确定的耐药性突变具有预测能力。它们还将为合理设计 新型抗菌剂。

 DESCRIPTION (provided by applicant): Project Summary Antibiotic-resistant microbes are once again a major threat to human health worldwide. Drugs once crucial in fighting the spread of deadly pathogens have become ineffective. The development of novel antimicrobials to solve this crisis will require detailed knowledge of the underlying mechanisms of antibiotic resistance, including the structural basis of resistance caused by mutations in antibiotic targets. The most important antibiotic target is the ribosome, the universal site of protein synthesis, and resistanc mutations have been identified in numerous species. Through a strong collaborative effort, this proposal capitalizes on the current state of genetics and X-ray crystallography of the ribosome from Thermus thermophilus to address fundamental aspects of antibiotic resistance. The aims of this proposal are: (1) determine the structural basis for phenotypic interaction among multiple antibiotic-resistance mutations that can potentially arise after sequential exposure to multiple antibiotic challenges; (2) monitor the evolution of secondary mutations that compensate for the fitness cost of deleterious antibiotic-resistance mutations. These aims are designed to give fundamental insights into mechanisms of antibiotic resistance, and findings will be applicable to the rational design of drugs directed against antibiotic-resistant pathogens. Achieving these aims will involve an innovative fusion of genetics and X-ray crystallography to determine the structures of mutant ribosomes. The bacterium T. thermophilus is especially suited as a model system due to its amenability to genetic manipulation and the suitability of its ribosomes for crystallization. Our proposal rests on a strong foundation of: (1) extensive experience in both genetics and X-ray crystallography, including a proven track record of the skills needed to achieve the proposed aims; (2) extensive preliminary results, including the structure determination of a number of antibiotic-resistant ribosomes; (3) an extensive working knowledge of the protein synthesis field and antibiotic-resistance, as indicated by a long track record of publications; (4) an excellent collaborative relationship between the two PIs. The accomplishment of the goals of this proposal will provide fundamental insights into the mechanism of antibiotic resistance, which will have predictive power regarding resistance mutations not yet identified. They will also create a valuable framework for the rational design of novel antimicrobials.