A new pathway for transmembrane electron transfer in photosynthetic reaction centers of Rhodobacter sphaeroides not involving the excited special pair.
A new pathway for transmembrane electron transfer in photosynthetic reaction centers of Rhodobacter sphaeroides not involving the excited special pair.
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球形红杆菌光合反应中心跨膜电子转移的新途径，不涉及激发的特殊对。
DOI：
10.1021/bi9703756
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发表时间：
1997
期刊：
影响因子：
2.9
通讯作者：
R. van Grondelle
中科院分区：
文献类型：
--
作者：
M. V. van Brederode;M. Jones;F. van Mourik;I. V. van Stokkum;R. van Grondelle
细菌光合作用中的电子传递是由一对特殊的细菌叶绿素（P*）的第一单重激发态驱动的。我们已经研究了电子转移的第一个步骤中的一个突变体的Rhodobacter sphaeroides反应中心，其中电荷分离P* 显着放缓。结果首次提供了明确的证据，即在反应中心的活性分支（B（A））中的单体细菌叶绿素的激发驱动超快跨膜电子转移，而不涉及P*，展示了一种新的和有效的机制，太阳能在光合作用中的转换。最丰富的电荷分离中间态可能是P+B（A）-，它在200 fs内从B（A）* 形成，并以6.5 ps的寿命衰变为P+H（A）-。我们还看到了B（A）+H（A）-态参与旁路途径的证据。
It is generally accepted that electron transfer in bacterial photosynthesis is driven by the first singlet excited state of a special pair of bacteriochlorophylls (P*). We have examined the first steps of electron transfer in a mutant of the Rhodobacter sphaeroides reaction center in which charge separation from P* is dramatically slowed down. The results provide for the first time clear evidence that excitation of the monomeric bacteriochlorophyll in the active branch of the reaction center (B(A)) drives ultrafast transmembrane electron transfer without the involvement of P*, demonstrating a new and efficient mechanism for solar energy transduction in photosynthesis. The most abundant charge-separated intermediate state probably is P+B(A)-, which is formed within 200 fs from B(A)* and decays with a lifetime of 6.5 ps into P+H(A)-. We also see evidence for the involvement of a B(A)+H(A)- state in the alternative pathway.