通过cystathionineβ-synthase通过转硫路径的气体抑制
Neil R McFarlane1, Jiangli Gui1, Julianna Oláh2
1Department of Chemistry, KU Leuven, Celestijnenlaan 200f-box 2404, B-3001 Leuven, Belgium. neilrory.mcfarlane@kuleuven.be.
Physical chemistry chemical physics : PCCP
|June 4, 2024
概括
一氧化碳或氧化与人体氨酸β-合成酶结合,通过破坏PLP辅因子的活性部位来抑制酶活性. 这通过一种机械信号通路发生,该通路由气体连接体与血红组结合启动.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 结构生物学 结构生物学
背景情况:
- 转硫路径对于哺乳动物的氨酸和同氨酸平衡至关重要.
- 人类氨酸β-合成酶 (CBS) 是该途径中的关键酶,具有调节性血红基和氨酸5'-酸盐 (PLP) 活性位点.
- 血结合的CO或NO抑制了CBS,但这种全调节的精确机制尚未完全理解.
研究的目的:
- 阐明 CO 和 NO 结合人类CBS 血红组的结构机制,从而抑制 PLP 依赖性催化.
- 通过量子化学计算验证实验观察到的结合模式.
- 通过分子动力学模拟,研究传播到PLP活性部位的远程结构变化.
主要方法:
- 量子化学计算以模型化CO和NO结合.
- 模拟分子动力学以追踪结构变化.
- 分析键网络和蛋白质动态.
主要成果:
- 气体连接体与血红组结合会导致囊蛋白失调.
- 这种失调破坏了血结合的氨酸和邻近的氨酸残留物之间的键.
- 这种破坏引发了一系列结构变化,包括螺旋再定位和PLP辅因子位移,最终影响PLP的催化构造.
结论:
- 这项研究支持CBS抑制的机械信号模型.
- 通过CO/NO对CBS的体抑制涉及从血红蛋白传播到PLP活性部位的扩散形状变化.
- 了解这种信号通路对于理解CBS调节和潜在的治疗干预至关重要.
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