Redox transients of P680 associated with the incremental chlorophyll‐ a fluorescence yield rises elicited by a series of saturating flashes in diuron‐treated photosystem II core complex of Thermosynechococcus vulcanus

Autor: Gábor Sipka, Qingjun Zhu, Petar H. Lambrev, László Kovács, Pavel Müller, Melinda Magyar, Guangye Han, Yanan Xiao, Győző Garab, Jian Ren Shen, Klaus Brettel
Přispěvatelé: Biological Research Centre [Budapest] (BRC), Hungarian Academy of Sciences (MTA), Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institute of Botany [Beijing] (IB-CAS), Chinese Academy of Sciences [Beijing] (CAS), Okayama University, Ostravská univerzita / University of Ostrava, Département Biochimie, Biophysique et Biologie Structurale (B3S), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Photocatalyse et Biohydrogène (LPB), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Biologie Intégrative de la Cellule (I2BC), Dept Biol, University of Missouri [Columbia] (Mizzou), University of Missouri System-University of Missouri System
Jazyk: angličtina
Rok vydání: 2019
Předmět:
0106 biological sciences
Pheophytin
Photosystem II
Physiology
[SDV]Life Sciences [q-bio]
p-680
Kinetics
pheophytin
Analytical chemistry
Primary charge separation
Plant Science
Cyanobacteria
01 natural sciences
03 medical and health sciences
chemistry.chemical_compound
absorbency changes
reduction kinetics
Ultrafast laser spectroscopy
recombination pathways
Genetics
primary-charge separation
030304 developmental biology
particles
0303 health sciences
Chemistry
Chlorophyll A
absorption-spectroscopy
Photosystem II Protein Complex
primary electron-donor
excitation
P680
Cell Biology
General Medicine
[SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics
Fluorescence
[SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry
Molecular Biology/Biophysics
Yield (chemistry)
Oxidation-Reduction
010606 plant biology & botany
Zdroj: Physiologia Plantarum
Physiologia Plantarum, 2019, Photosynthesis, 166 (1), pp.22-32. ⟨10.1111/ppl.12945⟩
Physiologia Plantarum, Wiley, 2019, 166 (1), pp.22--32. ⟨10.1111/ppl.12945⟩
Physiologia Plantarum, Wiley, 2019, Photosynthesis, 166 (1), pp.22-32. ⟨10.1111/ppl.12945⟩
ISSN: 0031-9317
1399-3054
DOI: 10.1111/ppl.12945⟩
Popis: International audience; Recent chlorophyll-a fluorescence yield measurements, using single-turnover saturating flashes (STSFs), have revealed the involvement of a rate-limiting step in the reactions following the charge separation induced by the first flash (Magyar et al. 2018). As also shown here, in diuron-inhibited PSII core complexes isolated from Thermosynechococcus vulcanus the fluorescence maximum could only be reached by a train of STSFs. In order to elucidate the origin of the fluorescence yield increments in STSF series, we performed transient absorption measurements at 819 nm, reflecting the photooxidation and re-reduction kinetics of the primary electron donor P680. Upon single flash excitation of the dark-adapted sample, the decay kinetics could be described with lifetimes of 17 ns (~50%) and 167 ns (~30%), and a longer-lived component (~20%). This kinetics are attributed to re-reduction of P680•+ by the donor side of PSII. In contrast, upon second-flash (with Δt between 5 μs and 100 ms) or repetitive excitation, the 819 nm absorption changes decayed with lifetimes of about 2 ns (~60%) and 10 ns (~30%), attributed to recombination of the primary radical pair P680•+ Pheo•- , and a small longer-lived component (~10%). These data confirm that only the first STSF is capable of generating stable charge separation - leading to the reduction of QA ; and thus, the fluorescence yield increments elicited by the consecutive flashes must have a different physical origin. Our double-flash experiments indicate that the rate-limiting steps, detected by chlorophyll-a fluorescence, are not correlated with the turnover of P680. This article is protected by copyright. All rights reserved.
Databáze: OpenAIRE
Externí odkaz: