绘制一个保护途径的初始阶段,该途径增强了Lytic多糖单氧酶的催化周转
Jingming Zhao1, Ying Zhuo1, Daniel E Diaz2
1Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
Journal of the American Chemical Society
|September 9, 2023
概括
依赖铜的酸多糖单氧酶 (LPMOs) 使用一种涉及过渡中间体的保护途径,以防止在催化过程中损害活性部位. 这种机制可以增加酶的循环和寿命.
科学领域:
- 生物化学
- 酵素学
- 生物有机化学
背景情况:
- 氧化酶和过氧化酶使C-H键功能化,但可能会损害活性部位.
- 酶必须在合和不合的循环过程中防止活性部位残留物的氧化损伤.
研究的目的:
- 研究依赖铜的酸多糖单氧酶 (LPMOs) 的保护机制.
- 描述参与预防活性部位损伤的短暂中间体.
主要方法:
- 停流光谱学
- 有针对性的突变发生
- TD-DFT计算方法
- 高能分辨率光检测X射线吸收光谱
- 电子磁共振光谱学
主要成果:
- 从过氧化或过氧酸中形成的Cu (II) - (基) 中间体.
- 观察到这种中间体与氨酸的反应,形成Cu(II) - 氨酸基对.
- 已证明活性部位的恢复和重新进入催化循环.
结论:
- LPMOs具有对氧化损伤的内在保护途径.
- 这种途径涉及短暂的基质中间体,以最大限度地减少对胺残留物的损害.
- 保护机制提高了酶的寿命和触媒效率.
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