[FeFe]酶如何促进双向质子转移
Moritz Senger1, Viktor Eichmann1, Konstantin Laun1
1Experimental Molecular Biophysics, Department of Physics , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany.
Journal of the American Chemical Society
|October 4, 2019
概括
研究人员研究了[FeFe]酶中的质子转移,这些酶对转化至关重要. 他们发现质子转移在减少状态下是连续的,
科学领域:
- 生物化学
- 生物能源
- 酵素学
背景情况:
- 酶是催化分子 (H2) 和质子的相互转换的金属酶.
- [FeFe]-酶以高的H2循环率而闻名,激发生物模拟H2生产.
- 尽管对其活性部位进行了广泛的研究,但[FeFe]酶中的质子转移机制仍然不明.
研究的目的:
- 阐明[FeFe]酶中催化质子转移的机制.
- 在光降解过程中调查结网络的动态变化.
- 为了确定参与质子转移的特定氨基酸残留物.
主要方法:
- 在现场使用红外差异光谱.
- 研究了来自Chlamydomonas reinhardtii的[FeFe]酶.
- 在光还原过程中对结网的动态变化进行了评估.
主要成果:
- 在氧化状态 (Hox) 中,质子转移似乎受损,但在减少状态 (Hred) 中是连续的.
- 发现了谷氨酸 (E141) 和氨酸 (R148) 的过渡性质子变化.
- 通过这些特定残留物促进了双向质子转移.
结论:
- 连续的质子转移发生在减少的[FeFe]-酶状态下.
- 氨酸R148和谷氨酸E141在促进质子转移方面发挥着至关重要的作用.
- 这项研究为化酶中的质子中继机制提供了分子洞察力.
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