The relation between the electron spin polarization of the donor triplet state of the photosynthetic reaction center from Rhodopseudomonas viridis and the redox state of the primary acceptor

FEBS Letters

Gast, P.¹  Schaafsma, T.J.¹  van Wijk, F.G.H.¹ 

[1] Agricultural University, Laboratory of Molecular Physics, De Dreijen 11, 6703 BC Wageningen, The Netherlands

关键词: Triplet state electron spin polarization;    Bacterial photosynthesis;    EPR;    Reaction cente;    Redox state;   

DOI  :  10.1016/0014-5793(86)80988-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The hypothesis [(1986) Photobiochem. Photobiophys. 11, 95-100] that the temperature dependence of the electron spin polarization (ESP) pattern of the Δm = ± 1 EPR spectrum of the triplet state PR of the Rhodopseudomonas viridis reaction center is caused by magnetic interaction between the reduced menaquinone-iron complex Q⁻Fe²⁺ and the electron spin on I⁻ (reduced bacteriopheophytin b), which is part of the radical pair P⁺I⁻ (P⁺ is the oxidized primary electron donor P960) has been investigated. It was found that the AEAEAE ESP pattern of the EPR spectrum detected at T > 20 K changes into the usual AEEAAE pattern, when Q⁻Fe²⁺ is photochemically converted into Q²⁻Fe²⁺. This demonstrates that the presence of Q⁻ in Q⁻Fe²⁺ is a necessary condition to obtain the AEAEAE ESP pattern.

【 授权许可】

Unknown