作者
Chang Sun, Alexander T Taguchi, Nathan J Beal, Patrick J O’Malley, Sergei A Dikanov, Colin A Wraight
发表日期
2015/11/19
期刊
The journal of physical chemistry letters
卷号
6
期号
22
页码范围
4541-4546
出版商
American Chemical Society
简介
Unlike photosystem II (PSII) in higher plants, bacterial photosynthetic reaction centers (bRCs) from Proteobacteria have an additional peripheral membrane subunit “H”. The H subunit is necessary for photosynthetic growth, but can be removed chemically in vitro. The remaining LM dimer retains its activity to perform light-induced charge separation. Here we investigate the influence of the H subunit on interactions between the primary semiquinone and the protein matrix, using a combination of site-specific isotope labeling, pulsed electron paramagnetic resonance (EPR), and density functional theory (DFT) calculations. The data reveal substantially weaker binding interactions between the primary semiquinone and the LM dimer than observed for the intact bRC; the amount of electron spin transferred to the nitrogen hydrogen bond donors is significantly reduced, the methoxy groups are more free to rotate, and the …
学术搜索中的文章
C Sun, AT Taguchi, NJ Beal, PJ O'Malley, SA Dikanov… - The journal of physical chemistry letters, 2015