质子化对炭致命因子早期转移的影响:分子动力学模拟和里程碑理论的动力学
Piao Ma1, Alfredo E Cardenas2, Mangesh I Chaudhari3
1Department of Chemistry, University of Texas at Austin , Austin, Texas 78712, United States.
Journal of the American Chemical Society
|October 12, 2017
概括
分子动力学模拟揭示了致命因子 (LF) 的N端段如何透到炭病通道. 质子状态极大地影响了这个最初的,可能不可逆转的步骤,形成了一个通道阻塞.
科学领域:
- 生物物理
- 计算生物学
- 生物化学
背景情况:
- 致命因子 (LF) 是炭毒素的关键组成部分.
- 了解LF通过炭通道的转移对于制定对策至关重要.
- 在LF的N端段启动透过程.
研究的目的:
- 通过炭病道研究LFN端段透的分子机制.
- 阐明氨基酸质子化状态在这个过程中的作用.
- 使用先进的模拟技术提取透的动态信息.
主要方法:
- 详细的分子动力学模拟.
- 显式溶剂模型
- 跨多个时间尺度 (纳米秒到毫秒) 的动力分析的里程碑理论.
主要成果:
- 非结构化的N端链导致LF透.
- 初始透对氨基酸的质子化状态非常敏感.
- 高质子状态便于通过通道和 phi (φ) .
- 最初的透事件可能是不可逆转的,在通道口产生"".
结论:
- 质子化依赖的初始透事件是LF转移的关键瓶.
- 这种机制可能是抑制炭毒素活性的目标.
- 模拟提供了通过膜通道透蛋白质的动态.
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