甲素耐药黄金葡萄球菌的素结合蛋白2a的构成动力学,体通信网络和催化能力
Kiran V Mahasenan1, Rafael Molina2, Renee Bouley1
1Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States.
Journal of the American Chemical Society
|January 19, 2017
概括
金色葡萄球菌中的青素结合蛋白2a (PBP2a) 使用异质部位抵抗β-乳酸菌抗生素. 这种机制涉及循环运动,打开活性部位,使PBP2a能够逃避抑制,从而导致抗生素耐药性.
科学领域:
- 结构生物学
- 微生物学
- 药物化学
背景情况:
- 贝塔乳酸抗生素向糖细胞壁的生物合成.
- 黄金葡萄球菌使用素结合蛋白2a (PBP2a) 进行抗药性.
- 通过偏好糖基质,PBP2a对beta- lactams进行歧视.
研究的目的:
- 阐明PBP2a的抵抗机制的分子基础.
- 了解PBP2a活动部位的全调节.
- 研究对β-乳糖仿真和抗性突变的结构性见解.
主要方法:
- 用三种β- 乳酸药物 (oxacillin,cefepime,ceftazidime) 复合的PBP2a的X射线结晶学
- 计算分析以关联全位结合与活性位点的形状变化.
- 模拟关键的催化步骤,包括基质结合和转移.
主要成果:
- 晶体结构显示PBP2a在白位与β-乳酸结合时处于"开放"或"部分开放"状态.
- 一个与活性部位相邻的循环运动被确定为形状变化的驱动因素.
- 计算模型阐明了从效应器结合部位到活性部位的全信号通路.
结论:
- 对PBP2a活性部位的开放和功能至关重要.
- 已识别的循环运动介于全和活性位点之间的通信.
- 了解这些结构动态为应对新出现的PBP2a耐药性提供了基础.
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