In photoinhibited photosystem II particles pheophytin photoreduction remains unimpaired

FEBS Letters

Šetlíková, Eva²  Allakhverdiev, Suleiman I.¹  Klimov, Vyacheslav V.¹  Šetlík, Ivan² 

[1] Institute of Soil Science and Photosynthesis, USSR Academy of Sciences, 142292 Pushchino, USSR;Institute of Microbiology, Czechoslovak Academy of Sciences, 37981 Tr̆ebon̆, Czechoslovakia

关键词: Photoinhibition;    Charge separation;    Pheophytin;    Oxygen-evolving PS II particle;    (Pea chloroplasts);    PS;    photosystem;    RC;    reaction center;    P-680;    the primary electron donor;    Pheo (pheophytin);    the intermediary electron acceptor;    QA;    the primary (quinone) electron acceptor in PS II;    F o;    F v;    F m;    constant;    variable;    maximum fluorescence;    HRR;    Hill reaction rate (H2O å BQ);    BQ;    p-benzoquinone;    Mes;    2-(N-morpholino)ethanesulfonic acid;   

DOI  :  10.1016/0014-5793(87)80576-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Oxygen-evolving photosystem II particles (DT 20) isolated from pea chloroplasts by digitonin-Triton X-100 fractionation were photoinhibited with 150 W·m⁻² white light, at 20°C under three conditions: aerobic, anaerobic and strongly reducing (E _h poised to approx. −250 mV with dithionite). Hill reaction rate (H₂O → BQ) and variable fluorescence (F _v) declined in parallel in all three cases with shortening half times: 30, 10 and 2.5 min, respectively. Light-induced absorbance changes at 685 nm characteristic of reversible photoaccumulation of reduced pheophytin (E _h ≈ −250 mV) remained essentially unchanged. We conclude that the three types of photoinhibitory treatment do not impair the separation of charges between chlorophyll P-680 and pheophytin in the photosystem II reaction center.

【 授权许可】

Unknown