Spectroscopic characterization of reaction center crystals from the carotenoid‐containing wild‐type strain Rhodobacter sphaeroides Y

FEBS Letters

Reiss-Husson, F.²  Mäntele, W.¹ 

[1] Institut für Biophysik und Strahlenbiologie der Universität Freiburg, Albertstraße 23, D-7800 Freiburg, FRG;Laboratoire de Photosynthèse, Centre National de Recherche Scientifique, BP no. 1, F-91190 Gif-sur-Yvette, France

关键词: Photochemical reaction center;    Membrane protein crystal;    Microspectrophotometry;    Linear dichroism;    Carotenoid;    BChl a;    bacteriochlorophyll a;    BPheo a;    bacteriopheophytin a;    QA;    QB;    quinone A;    quinone B;    RC;    reaction center;    P;    primary electron donor;   

DOI  :  10.1016/0014-5793(88)80549-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Thin three-dimensional crystals of the photochemical reaction center from Rhodobacter sphaeroides wild-type strain Y were investigated with microspectrophotometric methods. Absorbance and linear dichroism spectra were obtained for two crystal forms with the same type of unit cell, but grown in different morphological forms. High dichroism was found for the Q_x and the Q_y transitions of the bacteriopheophytin as well as for the Q_y transitions of the accessory bacteriochlorophylls and the bacteriochlorophylls forming the primary electron donor. Low absorption and dichroism of the carotenoid transitions in the plane of the crystal suggests a large component out of the crystal plane. Photoactivity of the crystal was demonstrated by light-induced charge separation. The analysis of the rates of charge recombination indicates that almost all reaction centers in the crystal (> 90%) contain the secondary electron acceptor Q_B.

【 授权许可】

Unknown