Quantum chemical elucidation of a sevenfold symmetric bacterial antenna complex.
Quantum chemical elucidation of a sevenfold symmetric bacterial antenna complex.
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DOI：
10.1007/s11120-022-00925-8
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发表时间：
2023-04
影响因子：
3.7
通讯作者：
Cogdell, Richard J.
中科院分区：
文献类型：
--
作者：
Cupellini, Lorenzo;Qian, Pu;Nguyen-Phan, Tu C.;Gardiner, Alastair T.;Cogdell, Richard J.
紫色细菌的捕光复合体2（LH 2）是研究最多的光合天线复合体之一。它的对称结构和环状细菌叶绿素排列使其成为理论家和光谱学家的理想系统。来自大多数细菌物种的LH 2复合物被认为具有八重或九重对称性，但最近来自细菌Mch的七重对称LH 2结构。通过冷冻电子显微镜解决了紫脓病。这种LH 2还具有独特的近红外吸收和圆二色性（CD）光谱特性。在这里，我们使用原子的策略来阐明Mch的光谱特性。purpuratum LH 2，并了解与最常研究的来自Rbl的LH 2的差异。嗜酸乳杆菌我们的策略利用了分子动力学模拟，多尺度极化量子力学/分子力学计算和线形模拟的组合。我们的计算表明，LH 2复合物的光谱特性调谐的网站能量和激子耦合，这反过来又取决于细菌叶绿素的结构波动。我们的策略被证明是有效的，在再现的吸收和CD光谱的两个LH 2复合物，并在揭示其差异的起源。这项工作证明，它是可能的，以获得洞察的光谱调谐策略的紫色细菌通过定量模拟其天线复合物的光谱特性。在线版本包含补充材料，可通过10.1007/s11120-022-00925-8获取。
The light-harvesting complex 2 (LH2) of purple bacteria is one of the most studied photosynthetic antenna complexes. Its symmetric structure and ring-like bacteriochlorophyll arrangement make it an ideal system for theoreticians and spectroscopists. LH2 complexes from most bacterial species are thought to have eightfold or ninefold symmetry, but recently a sevenfold symmetric LH2 structure from the bacterium Mch. purpuratum was solved by Cryo-Electron microscopy. This LH2 also possesses unique near-infrared absorption and circular dichroism (CD) spectral properties. Here we use an atomistic strategy to elucidate the spectral properties of Mch. purpuratum LH2 and understand the differences with the most commonly studied LH2 from Rbl. acidophilus. Our strategy exploits a combination of molecular dynamics simulations, multiscale polarizable quantum mechanics/molecular mechanics calculations, and lineshape simulations. Our calculations reveal that the spectral properties of LH2 complexes are tuned by site energies and exciton couplings, which in turn depend on the structural fluctuations of the bacteriochlorophylls. Our strategy proves effective in reproducing the absorption and CD spectra of the two LH2 complexes, and in uncovering the origin of their differences. This work proves that it is possible to obtain insight into the spectral tuning strategies of purple bacteria by quantitatively simulating the spectral properties of their antenna complexes. The online version contains supplementary material available at 10.1007/s11120-022-00925-8.
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影响因子：
3.3
作者：
Cupellini, Lorenzo;Jurinovich, Sandro;Mennucci, Benedetta
通讯作者：
Mennucci, Benedetta
影响因子：
--
作者：
GUDOWSKANOWAK, E;NEWTON, MD;FAJER, J
通讯作者：
FAJER, J
DOI：
10.1021/acs.jpcb.0c05180
发表时间：
2020-10-01
期刊：
The journal of physical chemistry. B
影响因子：
--
作者：
Cupellini L;Lipparini F;Cao J
通讯作者：
Cao J
影响因子：
5.5
作者：
Curutchet, Caries;Munoz-Losa, Aurora;Mennucci, Benedetta
通讯作者：
Mennucci, Benedetta
影响因子：
4.6
作者：
Ferretti M;Hendrikx R;Romero E;Southall J;Cogdell RJ;Novoderezhkin VI;Scholes GD;van Grondelle R
通讯作者：
van Grondelle R