检查在Bacteriorhodopsin中的质子转移通路的出口处拟议的质子化水集群
Manoj Mandal1, Tomoyasu Noji2,3, Keisuke Saito2,3
1Department of Education in Science and Mathematics, Regional Institute of Education, National Council of Educational Research and Training, Shyamla Hills, Bhopal, Madhya Pradesh 462002, India.
The journal of physical chemistry. B
|October 6, 2025
概括
像离子 (H3O+) 这样的质子化水物种不太可能在背后的hodopsin中形成.
科学领域:
- 生物物理学的生物物理.
- 计算化学计算化学
背景情况:
- 光谱学研究表明,在细菌黄素的质子转移通路的细胞外终点处,有质子化的水物种.
- 拟议的物种包括离子 (H3O+) 或H5O2+.
研究的目的:
- 通过计算来研究H3O+和H5O2+在bacteriorhodopsin中的W403位点形成的可行性.
- 根据先前的光谱证据重新评估假设.
主要方法:
- 利用了高分辨率的晶体结构数据的背后的hodopsin.
- 执行了量子力学/分子力学 (QM/MM) 的计算.
- 优化了几何形状和分析了潜在能量表面.
主要成果:
- 在W403地点模拟的H3O+导致了与蛋白质环境不相容的金字塔形状,不稳定的几何形状.
- H3O+分解成中性水分子,质子转移到Glu194或Glu204.
- 分析排除了H3O+和H5O2+的稳定,这是由于不利的潜在能量表面和缺乏低屏障结的原因.
结论:
- 无论是H3O+还是H5O2+都无法在巴克蒂奥罗多普辛的拟议地点实现.
- 这些发现表明,这种质子化水物种不太可能在高效的质子转移途径中形成.
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