Delayed fluorescence emitted from light harvesting complex II and photosystem II of higher plants in the 100 ns–5 μs time domain

FEBS Letters

Steffen, R.¹  Christen, G.¹  Renger, G.¹ 

[1] Max-Volmer-Institute for Biophysical Chemistry and Biochemistry, Technical University Berlin, Straße des 17. Juni 135, D-10623 Berlin, Germany

关键词: Delayed fluorescence;    Quantum yield;    Photosystem II;    Light harvesting complex;    Water oxidizing complex;    Chl;    chlorophyll;    1Chl*;    excited singlet state of Chl;    DF;    delayed fluorescence;    LHCII;    light harvesting complex II;    MCP;    multichannel plate;    PSII;    photosystem II;    P680;    Pheo and QA;    photoactive chlorophyll;    a pheophytin and a primary quinone acceptor;    respectively;    of PSII;    S i;    redox states of the WOC;    WOC;    water oxidizing complex;    YZ;    redox active tyrosine of polypeptide D1;   

DOI  :  10.1016/S0014-5793(00)01641-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

This study presents the first report on delayed fluorescence (DF) emitted from spinach thylakoids, D1/D2/Cytb-559 preparations and solubilized light harvesting complex II (LHCII) in the ns time domain after excitation with saturating laser flashes. The use of a new commercially available multichannel plate with rapid gating permitted a sufficient suppression of detector distortions due to the strong prompt fluorescence. The following results were obtained: (a) in dark-adapted thylakoids, the DF amplitudes at 100 ns and 5 μs after each flash of a train of saturating actinic pulses exhibit characteristic period four oscillations of opposite sign: the DF amplitudes at 100 ns oscillate in the same manner as the quantum yield of prompt fluorescence, whereas those at 5 μs resemble the oscillation of the μs kinetics of P680⁺ reduction in samples with an intact water oxidizing complex, (b) the quantum yield of total DF emission in the range up to a few μs is estimated to be <10⁻⁴ for thylakoids, (c) the DF of D1/D2/Cytb-559 exhibits a monophasic decay with τ≈50 ns, (d) DF emission is also observed in isolated LHCII with biphasic decay kinetics characterized by τ values of 65 ns and about 800 ns, (e) in contrast to thylakoids, the amplitudes of DF in D1/D2/Cytb-559 preparations and solubilized LHCII do not exhibit any oscillation pattern and (f) all spectra of DF from the different sample types are characteristic for emission from the lowest excited singlet state of chlorophyll a. The implications of these findings and problems to be addressed in future research are briefly discussed.

【 授权许可】

Unknown