Charge accumulation at the reducing side of system 2 of photosynthesis
A study was made of the reactions between the primary and secondary electron acceptors of Photosystem 2 by measurements of the increase of chlorophyll fluorescence induced in darkness by dithionite or by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). The experiments were done either with chloroplasts to which hydroxylamine or carbonylcyanide-p-trifluoromethoxyphenylhydrazone (FCCP) was added, or with chloroplasts treated with tris(hydroxymethyl)aminomethane (Tris) to which phenylenediamine and ascorbate were added as donor system. Under these conditions the fluorescence increase induced by dithionite or DCMU added after illumination with short light flashes was dependent on the flash number with a periodicity of two; it was large after an uneven number of flashes, and small after a long darktime or after an even number of flashes. The results are interpreted in terms of a model which involves a hypothetical electron carrier situated between Q and plastoquinone; this electron carrier is thought to equilibrate with plastoquinone in a two-electron transfer reaction; the results obtained with DCMU are explained by assuming that its midpoint potential is lowered by this inhibitor.
New results on the mode of action of 3,-(3,4-Dichlorophenyl)-1,1-dimethylurea in spinach chloroplasts
The action of 3-(3,4-dichlorophenyl)-1,1-dimethylurea on the water-splitting enzyme system Y of photosynthesis
The action of 2-anilinothiophenes as accelerators of the deactivation reactions in the watersplitting enzyme system of photosynthesis
Detection of rapid induction kinetics with a new type of high-frequency modulated chlorophyll fluorometer
The relationship between non-photochemical quenching of chlorophyll fluorescence and the rate of photosystem 2 photochemistry in leaves
High misses after odd flashes in oxygen evolution in thoroughly dark-adapted thylakoids from pea and Chenopodium album
Regulation of photosynthetic electron transport by bicarbonate formate and herbicides in isolated broken and intact chloroplasts
Interaction of 2-n-heptyl-4-hydroxyquinoline-N-oxide with photosystem II in chloroplasts and subchloroplast particles
D1-arginine257 mutants (R257E, K, and Q) of Chlamydomonas reinhardtii have a lowered QB redox potential: analysis of thermoluminescence and fluorescence measurements
A model of chlorophyll a fluorescence induction kinetics with explicit description of structural constraints of individual photosystem II units
On the polyphasic quenching kinetics of chlorophyll a fluorescence in algae after light pulses of variable length
Inhibition of electron flow and energy transduction in isolated spinach chloroplasts by the herbicide dinoseb
Time-resolved vibrational spectroscopy detects protein-based intermediates in the photosynthetic oxygen-evolving cycle
Environment of TyrZ in photosystem II from Thermosynechococcus elongatus in which PsbA2 is the D1 protein
Effect of calcium chelators on the formation and oxidation of the slowly relaxing reduced plastoquinone pool in calcium-depleted PSII membranes. Investigation of the F0 yield
Temperature effects on pea plants probed by simultaneous measurements of the kinetics of prompt fluorescence, delayed fluorescence and modulated 820 nm reflection
Investigation of the reactions of chlorophyll-a II in class II chloroplasts under repetitive double flash group excitation
Study of the chlorophyll fluorescence in chloroplasts and algae with the plastoquinone antagonist dibromothymoquinone
The rapid component of electron paramagnetic resonance signal II: a candidate for the physiological donor to photosystem II in spinach chloroplasts
Effect of 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone on the secondary electron acceptor B of photosystem II
Relationship between inhibitor binding by chloroplasts and inhibition of photosynthetic electron transport
Analysis of absorption changes in the ultraviolet related to charge-accumulating electron carriers in photosystem II of chloroplasts
The mechanism of reduction of the ubiquinone pool in photosynthetic bacteria at different redox potentials
A three-state model for energy trapping and chlorophyll fluorescence in photosystem II incorporating radical pair recombination
Reactions between primary and secondary acceptors of photosystem II in Chlorella pyrenoidosa under anaerobic conditions as studied by chlorophyll fluorescence
Effect of the transmembrane electric field on the photochemical and quenching properties of photosystem II in vivo
The semiquinone-iron complex of photosystem II: structural insights from ESR and theoretical simulation; evidence that the native ligand to the non-heme iron is carbonate
Flash-induced absorption changes of the primary donor of photosystem II at 820 nm in chloroplasts inhibited by low pH or tris-treatment
Louis Nico Marie Duysens (March 15, 1921-September 8, 2015): a leading biophysicist of the 20th century
Redox Reactions on the reducing side of photosystem II in chloroplasts with altered herbicide binding properties
Ubiquinone reduction and proton uptake by chromatophores of Rhodopseudomonas sphaeroides R-26: periodicity of two in consecutive light flashes
Primary reactions, plastoquinone and fluorescence yield in subchloroplast fragments prepared with deoxycholate
The effect of redox potential on the kinetics of fluorescence induction in pea chloroplasts. I. Removal of the slow phase
Damping of oscillations in the semiquinone absorption in reaction centers after successive flashes determination of the equilibrium between Q(-)AQB and QAQ(-)B
Primary and secondary electron donors in photosystem II of chloroplasts. Rates of electron transfer and location in the membrane
Inhibition of the reoxidation of the secondary electron acceptor of photosystem II by bicarbonate depletion
Electron acceptors of bacterial photosynthetic reaction centers. II. H+ binding coupled to secondary electron transfer in the quinone acceptor complex
Systems approach to excitation-energy and electron transfer reaction networks in photosystem II complex: model studies for chlorophyll a fluorescence induction kinetics
Biphasic reduction of cytochrome b559 by plastoquinol in photosystem II membrane fragments: evidence for two types of cytochrome b559/plastoquinone redox equilibria
Probing the role of chloride in Photosystem II from Thermosynechococcus elongatus by exchanging chloride for iodide
Deactivation processes in PsbA1-Photosystem II and PsbA3-Photosystem II under photoinhibitory conditions in the cyanobacterium Thermosynechococcus elongatus
The Tll0287 protein is a hemoprotein associated with the PsbA2-Photosystem II complex in Thermosynechococcus elongatus
Photosynthetic electron transport activity in heat-treated barley leaves: the role of internal alternative electron donors to photosystem II
In intact leaves, the maximum fluorescence level (F(M)) is independent of the redox state of the plastoquinone pool: a DCMU-inhibition study
The chlorophyll a fluorescence induction pattern in chloroplasts upon repetitive single turnover excitations: accumulation and function of QB-nonreducing centers
Probing the quinone binding site of photosystem II from Thermosynechococcus elongatus containing either PsbA1 or PsbA3 as the D1 protein through the binding characteristics of herbicides
Dependence of the deactivation reactions of photosystem II on the redox state of plastoquinone pool A varied under anaerobic conditions; Equilibria on the acceptor side of photosystem II
Kinetics of reduction of the primary donor of photosystem II. Influence of pH in various preparations
Properties of the proteinaceous component acting as apoenzyme for the functional plastoquinone redox groups on the acceptor side of system II
A study of dark luminescence in Chlorella. Background luminescence, 3-(3,4-dichlorophenyl)-1,1-dimethylurea-triggered luminescence and hydrogen peroxide chemiluminescence
Secondary electron transfer in reaction centers of Rhodopseudomonas sphaeroides. Out-of-phase periodicity of two for the formation of ubisemiquinone and fully reduced ubiquinone
Electron acceptors of photosynthetic bacterial reaction centers. Direct observation of oscillatory behaviour suggesting two closely equivalent ubiquinones
Characterization of two quenchers of chlorophyll fluorescence with different midpoint oxidation-reduction potentials in chloroplasts
A dynamic interaction between the bicarbonate ligand and photosystem II reaction center complexes in chloroplasts
Charge recombination in S(n)Tyr(Z)(•)Q(A)(-•) radical pairs in D1 protein variants of Photosystem II: long range electron transfer in the Marcus inverted region
Semiquinone-iron complex of photosystem II: EPR signals assigned to the low-field edge of the ground state doublet of QA•-Fe2+ and QB•-Fe2+
The artificial humic substance HS1500 does not inhibit photosynthesis of the green alga Desmodesmus armatus in vivo but interacts with the photosynthetic apparatus of isolated spinach thylakoids in vitro
Influence of the redox potential of the primary quinone electron acceptor on photoinhibition in photosystem II
Effect of different methods of Ca2+ extraction from PSII oxygen-evolving complex on the QA- oxidation kinetics
Development of a minimized model structure and a feedback control framework for regulating photosynthetic activities
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