Probing the secondary quinone (QB) environment in photosynthetic bacterial reaction centers by light‐induced FTIR difference spectroscopy

FEBS Letters

Nabedryk, E.¹  Thibodeau, D.L.¹  Breton, J.¹  Berthomieu, C.¹ 

[1]DBCM/SBE, C.E.N. Saclay, 91191 Gif-sur-Yvette Cedex, France

关键词: Fourier transform infrared spectroscopy;    Bacterial reaction center;    Photosynthesis;    Primary quinone;    Secondary quinone;    Ubiquinone;    FTIR;    Fourier transform infrared spectroscopy;    QA (QB);    primary (secondary) quinone electron acceptor;    P;    primary electron donor;    RC;    reaction center;    UQ;    ubiquinone;    DAD;    diaminodurene;   

DOI  :  10.1016/0014-5793(91)81014-Y

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The photoreduction of the secondary electron acceptor, Q_B, has been characterized by light-induced Fourier transform infrared difference spectroscopy of Rb. sphaeroides and Rp. viridis reaction centers. The reaction centers were supplemented with ubiquinone (UQ₁₀ or UQ₀). The Q_B⁻ state was generated either by continuous illumination at very low intensity or by single flash in the presence of redox compounds which rapidly reduce the photooxidized primary electron donor P⁺. This approach yields spectra free from P and P⁺ contributions making possible the study of the microenvironment of Q_B and Q_B⁻. Assignments are proposed for the CO vibration of Q_B⁻ and tentatively for the C = O and C = C vibrations of Q_B.

【 授权许可】

Unknown