Mechanisms of Energy Transduction in Plant Photosynthesis: ESR, ENDOR and MOs of the Primary Acceptors
Mechanisms of Energy Transduction in Plant Photosynthesis: ESR, ENDOR and MOs of the Primary Acceptors
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植物光合作用能量传递机制：主要受体的 ESR、ENDOR 和 MO
DOI：
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发表时间：
1981
期刊：
影响因子：
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通讯作者：
J. Fajer
中科院分区：
文献类型：
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作者：
A. Forman;M. S. Davis;I. Fujita;L. K. Hanson;Kevin M Smith;J. Fajer
光系统（PS） I和II的还原初级受体与叶绿素和叶绿素阴离子的还原初级受体的光学、顺磁性和氧化还原性质的比较表明，叶绿素是PS I和PS II的主要还原产物。分子轨道计算提供了自由基电子谱的描述，并表明反应中心的发色团的蛋白质环境可能施加特定的取向并诱导一些叶绿素取代基的氢键。对绿色植物和紫色细菌的所有初级受体的研究表明，（细菌）叶绿素样受体可能是影响初级电荷快速分离的必要因素，因为它们允许供体和受体之间有利的轨道重叠。将这些结果外推到绿色细菌中，表明细菌叶绿素a和细菌叶绿素c可能在这些生物中起瞬时电子受体的作用。
Comparison of the optical, paramagnetic and redox properties of the reduced primary acceptors of Photosystems (PS) I and II with those of chlorophyll and pheophytin anions suggests that chlorophyll is the primary reduced product in PS I and pheophytin in PS II. Molecular orbital calculations provide a description of the electronic profiles of the radicals, and indicate that the protein environment of the chromophores in the reaction center may impose specific orientations and induce hydrogen bonding to some of the chlorophyll substituent groups. Examination of all the primary acceptors postulated for green plants and purple bacteria suggests that (bacterio)chlorophyll-like acceptors may be obligatory to effect the rapid primary charge separation, because they allow favorable orbital overlap between donor and acceptor. Extrapolation of these results to green bacteria suggests that bacteriochlorophyll a and bacteriopheophytin c may act as transient electron acceptors in these organisms.