Evolution and inhibition of beta-lactamase activity in antibiotic resistance

描述（由申请人提供）：丝氨酸-内酰胺酶的产生是革兰氏阴性细菌病原体对-内酰胺类抗生素的主要耐药机制之一，这些抗生素包括广泛使用的青霉素类和头孢菌素类，以及碳青霉烯类等最后的抗生素。新型内酰胺酶抑制剂的开发是迫切需要强调的持续突变的内酰胺酶。我们建议开发高亲和力的非共价内酰胺酶抑制剂，以保守的结构基序为目标，特别是那些扩展光谱内酰胺酶活性所必需的结构基序。这些抑制剂的原型已经被确定。具体来说，以CTX-M A类内酰胺酶为模型系统，我们的目标是：1)应用基于片段和结构引导的方法开发新的内酰胺酶抑制剂化学型；2)利用超高分辨率和室温x射线晶体学研究耐药性和配体结合；3)研究非共价抑制剂耐药突变的进化。这些实验将导致具有临床潜力的新型内酰胺酶抑制剂，同时对与耐药性进化相关的内酰胺酶突变提供更深入的了解。

DESCRIPTION (provided by applicant): The production of serine ¿-lactamase is one of the primary resistance mechanisms used by Gram-negative bacterial pathogens against ¿-lactam antibiotics, which include the widely used penicillins and cephalosporins, as well as last resort antibiotics such as the carbapenems. The development of novel ¿-lactamase inhibitors is a pressing need underscored by the continuing mutation of ¿-lactamases. We propose the development of high affinity non-covalent ¿-lactamase inhibitors by targeting conserved structural motifs, particularly those essential for extended spectrum ¿-lactamase activity. Prototypes of these inhibitors have already been identified. Specifically, using the CTX-M Class A ¿-lactamases as a model system, we aim to: 1) apply a fragment-based and structure-guided approach to develop novel ¿-lactamase inhibitor chemotypes; 2) study resistance and ligand binding by ultrahigh-resolution and room-temperature X-ray crystallography; and 3) investigate the evolution of resistance mutations against non-covalent inhibitors. These experiments will lead to new ¿- lactamase inhibitors with clinical potential, while providing a deeper understanding of ¿-lactamase mutations relevant to resistance evolution.