Sequence diversity and antibiotic resistance - a molecular model of short- and long-range effects of mutations in serine lactamases

序列多样性和抗生素耐药性——丝氨酸内酰胺酶突变的短期和长期影响的分子模型

• 批准号: 5427265
• 负责人: Professor Dr. Jürgen Pleiss
• 金额: --
• 依托单位: Abteilung für Technische Biochemie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2006-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5427265?language=en
• 关键词: Sequence; diversity; antibiotic; resistance; molecular

How do enzymes achive subrate specifity? More specifically, how do structural elements and individual residues contribute to substrate recognition? Serine lactamases are an interesting model to study the effect of exchange of individual residues on specifity. Due to enhanced selective pressure imposed by application of antibiotics, natural evolution has resulted in a broad variety of serine lactamase variants with activity towards extended-spectrum cephalosporins. Some of the mutations are in the substrate binding site and directly interact with the substrate, but many changes occur far from the substrate. While there are suggestions to describe short-range effects of mutants, the mechanism of long-range effects is not yet understood. Long-range effects are frequently observed in mutants created by diected evolution approaches. The goal of this project is to etablish a general, generic molecular model of specifity which describes short- and long-range effects of mutations on structure and dynamics of the protein and realtes them to biochemical properties. It is based on large-scale molecular dynamics simulations of variants in complex with covalently bound substrate intermediates, solvated in a water box. This modelling approach will then be generalized to other enzyme classes. Because no constraints are applied, the model is also capable of investigating the effect of different solvents.

酶是如何实现底物特异性的？更具体地说，结构元件和单个残基如何有助于底物识别？丝氨酸内酰胺酶是研究单个残基交换对特异性影响的有趣模型。由于应用抗生素所施加的选择性压力增强，自然进化导致了对超广谱头孢菌素具有活性的多种丝氨酸内酰胺酶变体。一些突变位于底物结合位点，并直接与底物相互作用，但许多变化发生在远离底物的地方。虽然有人建议描述突变体的短期效应，但长期效应的机制尚不清楚。在定向进化方法产生的突变体中经常观察到长程效应。该项目的目标是建立一个通用的，通用的特异性分子模型，描述突变对蛋白质结构和动力学的短期和长期影响，并将其与生物化学性质联系起来。它是基于大规模的分子动力学模拟的变体与共价结合的底物中间体，在水盒溶剂化的复杂。这种建模方法将推广到其他酶类。由于没有应用约束，该模型也能够研究不同溶剂的影响。