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Photosynthesis Research

, Volume 140, Issue 1, pp 1–19 | Cite as

Analyzing both the fast and the slow phases of chlorophyll a fluorescence and P700 absorbance changes in dark-adapted and preilluminated pea leaves using a Thylakoid Membrane model

  • N. E. BelyaevaEmail author
  • A. A. Bulychev
  • G. Yu. Riznichenko
  • A. B. Rubin
Original Article
  • 127 Downloads

Abstract

The dark-to-light transitions enable energization of the thylakoid membrane (TM), which is reflected in fast and slow (OJIPSMT or OABCDE) stages of fluorescence induction (FI) and P700 oxidoreduction changes (ΔA810). A Thylakoid Membrane model (T-M model), in which special emphasis has been placed on ferredoxin-NADP+-oxidoreductase (FNR) activation and energy-dependent qE quenching, was applied for quantifying the kinetics of FI and ΔA810. Pea leaves were kept in darkness for 15 min and then the FI and ΔA810 signals were measured upon actinic illumination, applied either directly or after a 10-s light pulse coupled with a subsequent 10-s dark interval. On the time scale from 40 µs to 30 s, the parallel T-M model fittings to both FI and ΔA810 signals were obtained. The parameters of FNR activation and the buildup of qE quenching were found to differ for dark-adapted and preilluminated leaves. At the onset of actinic light, photosystem II (PSII) acceptors were oxidized (neutral) after dark adaptation, while the redox states with closed and/or semiquinone QA(−)QB(−) forms were supposedly generated after preillumination, and did not relax within the 10 s dark interval. In qE simulations, a pH-dependent Hill relationship was used. The rate constant of heat losses in PSII antenna kD(t) was found to increase from the basic value kDconst, at the onset of illumination, to its maximal level kDvar due to lumenal acidification. In dark-adapted leaves, a low value of kDconst of ∼ 2 × 106 s−1 was found. Simulations on the microsecond to 30 s time scale revealed that the slow P-S-M-T phases of the fluorescence induction were sensitive to light-induced FNR activation and high-energy qE quenching. Thus, the corresponding time-dependent rate constants kD(t) and kFNR(t) change substantially upon the release of electron transport on the acceptor side of PSI and during the NPQ development. The transitions between the cyclic and linear electron transport modes have also been quantified in this paper.

Keywords

Chlorophyll a fluorescence yield Dissipative energy losses Electron transfer Model simulation Photosynthetic induction Photosystems I and II Proton transfer Transmembrane charge fluxes Non-photochemical quenching 

Abbreviations

Chl

Chlorophyll

Cyt b6f

Cytochrome b6f complex

CEF

Cyclic electron flow (around PSI)

ET

Electron transfer

ETC

Electron transport chain

Fd, Fdr

Ferredoxin

FL

Fluorescence

FNR

Ferredoxin-NADP+-oxidoreductase

F0

Minimal chlorophyll a fluorescence yield

Fm

Maximal chlorophyll a fluorescence yield (induced by multiturnover light pulses)

HL+, HS+

Protons in lumen (L), protons in stroma (S)

NADP+

Nicotinamide adenine dinucleotide phosphate, oxidized form

NPQ

Non-photochemical quenching (of the excited state of Chl a)

PFD

Photon flux density

Phe, Ph

Primary PSII electron acceptor, pheophytin

pHL, pHS

pH in lumen, in stroma

Pc

Plastocyanin

PQ

Plastoquinone

PQH2

Plastoquinol

PS II, PS I

Photosystem II, Photosystem I

PT

Proton transfer

P680, P680

Chlorophyll a acting as electron donor in PSII

P700

Chlorophyll a acting as electron donor in PSI

QA and QB

Primary and secondary plastoquinone electron acceptors of PSII

qE

Energy-dependent quenching

RC

Reaction center (of PS II, or of PS I)

WOC

Water-oxidizing complex

YZ

Tyrosine 161 of the PS II D1 polypeptide

ΔΨ

Electrical potential across the thylakoid membrane

Notes

Acknowledgements

This work was supported by the RFBR, Project No. 16-04-00318. We wish to thank Professor Wim J. Vredenberg (Wageningen University, The Netherlands) for thorough consideration of the manuscript and stimulating discussion. We are grateful to Reviewer 2 for critical reading and careful editing the manuscript. We thank Professor V. Z. Paschenko and Ph.D. I. V. Konyukhov (Biophysics Department, Moscow State University) for fruitful discussions.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

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© Springer Nature B.V. 2019

Authors and Affiliations

  • N. E. Belyaeva
    • 1
    Email author
  • A. A. Bulychev
    • 1
  • G. Yu. Riznichenko
    • 1
  • A. B. Rubin
    • 1
  1. 1.Department of Biophysics, Biology Faculty of the M.V. LomonosovMoscow State UniversityMoscowRussia

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