The Picosecond Kinetics of Non-Photochemical Quenching in Leaves in the Presence of Open and Closed Reaction Centers

Abstract By combining a high frequency modulation system for measurement of fluorescence with a phosphoroscope type apparatus for measurement of luminescence, recordings of fluorescence and luminescence induction kinetics under identical conditions were obtained. Both measuring systems tolerated the application of saturating pulses of white light for rapid, transient elimination of photochemical quenching at photosystem II reaction centers, thus allowing determination of the non-photochemical quenching component. The saturation pulse induction curves of luminescence are well correlated with the corresponding curves of fluorescence, suggesting that luminescence yield is lowered by the same type of non-photochemical quenching (mostly “energy dependent quenching”) as fluorescence. Hence, in order to evaluate luminescence signals in terms of the rate of charge recombination at photosystem II reaction centers, knowledge of fluorescence quenching is required.

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Chlorophyll fluorescence: How the quality of information about PAM instrument parameters may affect our research

10.1101/2021.05.12.443801 ◽

2021 ◽

Author(s):

Tim Nies ◽

Yuxi Niu ◽

Oliver Ebenhöh ◽

Shizue Matsubara ◽

Anna Matuszyńska

Keyword(s):

Data Science ◽

Measurement Techniques ◽

Mathematical Formulation ◽

Pulse Amplitude ◽

Data Interpretation ◽

Photochemical Quenching ◽

Non Photochemical Quenching ◽

Underlying Processes ◽

Kinetics Of

Chlorophyll a fluorescence is a powerful indicator of photosynthetic energy conversion in plants and photosynthetic microorganisms. One of the most widely used measurement techniques is Pulse Amplitude Modulation (PAM) fluorometry. Unfortunately, parameter settings of PAM instruments are often not completely described in scientific articles although their variations, however small these may seem, can influence measurements. We show the effects of parameter settings on PAM measurements. We first simulated fluorescence signals using a previously published computational model of photosynthesis. Then, we validated our findings experimentally. Our analysis demonstrates how the kinetics of non-photochemical quenching (NPQ) induction and relaxation are affected by different settings of PAM instrument parameters. Neglecting these parameters may mislead data interpretation and derived hypotheses, hamper independent validation of the results, and cause problems for mathematical formulation of underlying processes. Given the uncertainties inflicted by this neglect, we urge PAM users to provide detailed documentation of measurement protocols. Moreover, to ensure accessibility to the required information, we advocate minimum information standards that can serve both experimental and computational biologists in our efforts to advance system-wide understanding of biological processes. Such specification will enable launching a standardized database for plant and data science communities.

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Restoration of Rapidly Reversible Photoprotective Energy Dissipation in the Absence of PsbS Protein by Enhanced ΔpH

Journal of Biological Chemistry ◽

10.1074/jbc.m111.237255 ◽

2011 ◽

Vol 286 (22) ◽

pp. 19973-19981 ◽

Cited By ~ 78

Author(s):

Matthew P. Johnson ◽

Alexander V. Ruban

Keyword(s):

Higher Plants ◽

Electron Flow ◽

Photosynthetic Electron Transport ◽

Reaction Centers ◽

Photochemical Quenching ◽

Spectral Changes ◽

Intact Chloroplasts ◽

Harvesting Process ◽

Non Photochemical Quenching ◽

Psbs Protein

Variations in the light environment require higher plants to regulate the light harvesting process. Under high light a mechanism known as non-photochemical quenching (NPQ) is triggered to dissipate excess absorbed light energy within the photosystem II (PSII) antenna as heat, preventing photodamage to the reaction center. The major component of NPQ, known as qE, is rapidly reversible in the dark and dependent upon the transmembrane proton gradient (ΔpH), formed as a result of photosynthetic electron transport. Using diaminodurene and phenazine metasulfate, mediators of cyclic electron flow around photosystem I, to enhance ΔpH, it is demonstrated that rapidly reversible qE-type quenching can be observed in intact chloroplasts from Arabidopsis plants lacking the PsbS protein, previously believed to be indispensible for the process. The qE in chloroplasts lacking PsbS significantly quenched the level of fluorescence when all PSII reaction centers were in the open state (Fo state), protected PSII reaction centers from photoinhibition, was modulated by zeaxanthin and was accompanied by the qE-typical absorption spectral changes, known as ΔA535. Titrations of the ΔpH dependence of qE in the absence of PsbS reveal that this protein affects the cooperativity and sensitivity of the photoprotective process to protons. The roles of PsbS and zeaxanthin are discussed in light of their involvement in the control of the proton-antenna association constant, pK, via regulation of the interconnected phenomena of PSII antenna reorganization/aggregation and hydrophobicity.

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A four state parametric model for the kinetics of the non-photochemical quenching in Photosystem II

Biochimica et Biophysica Acta (BBA) - Bioenergetics ◽

10.1016/j.bbabio.2017.08.004 ◽

2017 ◽

Vol 1858 (10) ◽

pp. 854-864 ◽

Cited By ~ 4

Author(s):

Joris J. Snellenburg ◽

Matthew P. Johnson ◽

Alexander V. Ruban ◽

Rienk van Grondelle ◽

Ivo H.M. van Stokkum

Keyword(s):

Photosystem Ii ◽

Parametric Model ◽

Photochemical Quenching ◽

Non Photochemical Quenching ◽

Kinetics Of

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A simple routine for quantitative analysis of light and dark kinetics of photochemical and non-photochemical quenching of chlorophyll fluorescence in intact leaves

Photosynthesis Research ◽

10.1007/s11120-015-0097-x ◽

2015 ◽

Vol 124 (1) ◽

pp. 87-106 ◽

Cited By ~ 12

Author(s):

Wim Vredenberg

Keyword(s):

Chlorophyll Fluorescence ◽

Quantitative Analysis ◽

Photochemical Quenching ◽

Intact Leaves ◽

Non Photochemical Quenching ◽

Kinetics Of

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Light Absorption and Partitioning in Response to Nitrogen in Apple Leaves

HortScience ◽

10.21273/hortsci.33.3.541a ◽

1998 ◽

Vol 33 (3) ◽

pp. 541a-541

Author(s):

Lailiang Cheng ◽

Leslie H. Fuchigami ◽

Patrick J. Breen

Keyword(s):

High Light ◽

Thermal Dissipation ◽

Photochemical Quenching ◽

Light Conditions ◽

Psii Efficiency ◽

Fluorescence Measurements ◽

Free Radical Formation ◽

Highly Correlated ◽

Non Photochemical Quenching ◽

Leaf N

Bench-grafted Fuji/M26 apple trees were fertigated with different concentrations of nitrogen by using a modified Hoagland solution for 6 weeks, resulting in a range of leaf N from 1.0 to 4.3 g·m–2. Over this range, leaf absorptance increased curvilinearly from 75% to 92.5%. Under high light conditions (1500 (mol·m–2·s–1), the amount of absorbed light in excess of that required to saturate CO2 assimilation decreased with increasing leaf N. Chlorophyll fluorescence measurements revealed that the maximum photosystem II (PSII) efficiency of dark-adapted leaves was relatively constant over the leaf N range except for a slight drop at the lower end. As leaf N increased, non-photochemical quenching under high light declined and there was a corresponding increase in the efficiency with which the absorbed photons were delivered to open PSII centers. Photochemical quenching coefficient decreased significantly at the lower end of the leaf N range. Actual PSII efficiency increased curvilinearly with increasing leaf N, and was highly correlated with light-saturated CO2 assimilation. The fraction of absorbed light potentially used for free radical formation was estimated to be about 10% regardless of the leaf N status. It was concluded that increased thermal dissipation protected leaves from photo-oxidation as leaf N declined.

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Gradual Response of Cyanobacterial Thylakoids to Acute High-Light Stress—Importance of Carotenoid Accumulation

Cells ◽

10.3390/cells10081916 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1916

Author(s):

Myriam Canonico ◽

Grzegorz Konert ◽

Aurélie Crepin ◽

Barbora Šedivá ◽

Radek Kaňa

Keyword(s):

Single Cell ◽

Thylakoid Membrane ◽

Intermediate Phase ◽

Light Stress ◽

Fast Response ◽

High Light ◽

Photochemical Quenching ◽

Second Phase ◽

Ros Scavenging ◽

Non Photochemical Quenching

Light plays an essential role in photosynthesis; however, its excess can cause damage to cellular components. Photosynthetic organisms thus developed a set of photoprotective mechanisms (e.g., non-photochemical quenching, photoinhibition) that can be studied by a classic biochemical and biophysical methods in cell suspension. Here, we combined these bulk methods with single-cell identification of microdomains in thylakoid membrane during high-light (HL) stress. We used Synechocystis sp. PCC 6803 cells with YFP tagged photosystem I. The single-cell data pointed to a three-phase response of cells to acute HL stress. We defined: (1) fast response phase (0–30 min), (2) intermediate phase (30–120 min), and (3) slow acclimation phase (120–360 min). During the first phase, cyanobacterial cells activated photoprotective mechanisms such as photoinhibition and non-photochemical quenching. Later on (during the second phase), we temporarily observed functional decoupling of phycobilisomes and sustained monomerization of photosystem II dimer. Simultaneously, cells also initiated accumulation of carotenoids, especially ɣ–carotene, the main precursor of all carotenoids. In the last phase, in addition to ɣ-carotene, we also observed accumulation of myxoxanthophyll and more even spatial distribution of photosystems and phycobilisomes between microdomains. We suggest that the overall carotenoid increase during HL stress could be involved either in the direct photoprotection (e.g., in ROS scavenging) and/or could play an additional role in maintaining optimal distribution of photosystems in thylakoid membrane to attain efficient photoprotection.

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