Modulation of Millisecond Chlorophyll Luminescence by Non-Photochemical Fluorescence Quenching

1989 ◽  
Vol 44 (11-12) ◽  
pp. 966-970 ◽  
Author(s):  
W. Bilger ◽  
U. Schreiber
Keyword(s):  
Photosystem Ii ◽  
Fluorescence Quenching ◽  
High Frequency ◽  
Reaction Centers ◽  
Photochemical Quenching ◽  
Saturation Pulse ◽  
Induction Kinetics ◽  
Non Photochemical Quenching ◽  
Energy Dependent

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.

Mechanism of Non-Photochemical Chlorophyll Fluorescence Quenching. I. The Role of De-Epoxidised Xanthophylls and Sequestered Thylakoid Membrane Protons as Probed by Dibucaine

1995 ◽  
Vol 22 (2) ◽  
pp. 231 ◽  
Author(s):  
N Mohanty ◽  
HY Yamamoto
Keyword(s):  
Chlorophyll Fluorescence ◽  
Fluorescence Quenching ◽  
Xanthophyll Cycle ◽  
Thylakoid Membranes ◽  
Photochemical Quenching ◽  
Chlorophyll Fluorescence Quenching ◽  
Mechanism Of Inhibition ◽  
Non Photochemical Quenching ◽  
Energy Dependent

Dibucaine reportedly inhibits the light-induced transthylakoid proton gradient of chloroplasts without inhibiting energy-dependent non-photochemical chlorophyll fluorescence quenching (Laasch, H. and Weis, E. (1989). Photosynthesis Research 22, 137-146). We show that dibucaine can inhibit fluorescence quenching, depending on the de-epoxidation state of the xanthophyll cycle. Whereas dibucaine (20-40 μM) had little effect on fluorescence quenching in pre-illuminated-type thylakoids (loaded with zeaxanthin and antheraxanthin), it strongly inhibited quenching in dark-adapted-type thylakoids (no preinduction of de-epoxidation). Dibucaine inhibited lumen acidification similarly in both types of thylakoids and also the induction of violaxanthin de-epoxidation in dark-adapted thylakoids. Thus dark-adapted and pre-illuminated thylakoids differed in de-epoxidation states and their suspectibility to dibucaine inhibition of fluorescence quenching corresponded to this difference. The mechanism of inhibition of de-epoxidation by dibucaine is unclear. It could be due to the inhibition of lumen acidification but an inhibition of the violaxanthin available for de-epoxidation is not excluded. High dibucaine concentrations inhibited de-epoxidase activity directly. Dibucaine inhibition of fluorescence quenching, however, is not limited to the inhibition of de-epoxidation. Small but clear effects on fluorescence quenching were present in thylakoids even with de-epoxidation preinduced. Moreover, thylakoids with preinduced de-epoxidation were more resistant to dibucaine inhibition of fluorescene quenching when poised by salt treatments for proton partitioning into membrane-sequestered domains than when poised for proton partitioning into delocalised domains. We conclude that non-photochemical quenching of chlorophyll fluorescence depends on both de-epoxidised xanthophylls and sequestered proton domains in the thylakoid membranes

Photochemical and Non-Photochemical Quenching of Chlorophyll Fluorescence Induced by Hydrogen Peroxide

1989 ◽  
Vol 44 (3-4) ◽  
pp. 262-270 ◽  
Author(s):  
Christian Neubauer ◽  
Ulrich Schreiber
Keyword(s):  
Hydrogen Peroxide ◽  
Chlorophyll Fluorescence ◽  
Fluorescence Quenching ◽  
Ascorbate Peroxidase ◽  
Photochemical Quenching ◽  
Maximal Rate ◽  
Saturation Pulse ◽  
Non Photochemical Quenching ◽  
H 20

Abstract Chlorophyll Fluorescence. Fluorescence Quenching, Hydrogen Peroxide. Active Oxygen. Ascorbate Peroxidase Chlorophyll fluorescence quenching induced by H 20 2 in intact spinach chloroplasts was investi­gated with a modulation fluorometer which allows to distinguish between photochemical and non­ photochemical quenching components by the so-called saturation pulse method. Residual catalase activity was removed by washing and percoll gradient centrifugation. H2O2 was found to induce pronounced photochem ical and non-photochemical quenching, characteristic for the action of a Hill reagent, with a half-maximal rate already observed at 5 × 10-6 m . The saturation characteris­tics and maximal rate of H2O2-reduction were very similar to those of methylviologen reduction. H2O2-dependent quenching was stimulated by ascorbate and inhibited by cyanide and azide in agreement with previous findings by other researchers that H2O2-reduction involves the ascorbate peroxidase scavenging system and that the actual “Hill acceptor” is an oxidation product of ascorbate, i.e. monodehydroascorbate or dehydroascorbate. With well-coupled intact chloro­plasts reducing CO2 at 150 (μmol (mg Chl)-1h-1, iodoacetamide stopped CO2-dependent O2-evolution and consequent addition of 10″3 m H2O2 produced an O2-Solution rate of 240 (μmol (mg Chl)-1h-1 .It is concluded that light-dependent H 20 2 reduction is a very efficient reaction in intact chloroplasts. As H2O2 formation and consequent reduction also occur in vivo, the corre­sponding quenching should be considered when assimilatory electron flow is estimated from quenching coefficients. It is suggested that proton flux associated with H2O2-formation and reduc­tion may be important for the adjustment of appropriate ATP /NADPH ratios required for CO2-fixation in vivo. Furthermore, H2O2-reduction may serve as a valve reaction whenever Calvin cycle activity is limited by factors different from NADPH supply, thus protecting against photo-inhibitory damage.

Kinetic Relationship between Energy-Dependent Fluorescence Quenching, Light Scattering, Chlorophyll Luminescence and Proton Pumping in Intact Leaves

1988 ◽  
Vol 43 (11-12) ◽  
pp. 877-887 ◽  
Author(s):  
W. Bilger ◽  
U. Heber ◽  
U. Schreiber
Keyword(s):  
Light Scattering ◽  
Fluorescence Quenching ◽  
Pulse Method ◽  
Proton Pumping ◽  
Measuring System ◽  
Photochemical Quenching ◽  
Saturation Pulse ◽  
Kinetic Relationship ◽  
Intact Leaves ◽  
Energy Dependent

Abstract A measuring system was designed for simultaneous recording of modulated chlorophyll fluorescence and light scattering changes. The kinetic relationship was investigated between lightinduced changes in non-photochemical fluorescence quenching, as determined by the saturation pulse method, and in light scattering, as measured via the apparent absorbance change at 543 nm. Very similar, but not identical kinetics were observed, reflecting a close non-linear relationship between these two indicators of thylakoid membrane energization. Fluorescence was found more sensitive at low levels of energization, while scattering continued indicating further increases in energization when quenching already was saturated. A general relationship between quenching and scattering is demonstrated which holds irrespective of whether energization is varied during induction or via changes in light intensity or CO2 concentration. In the light-off responses, only part of fluorescence quenching was found to relax with the same kinetics as scattering. It is suggested that at high levels of energization slowly reversible membrane changes may be induced which have the potential of non-photochemical quenching at a low level of energization, and which are not accompanied by scattering changes. Neither quenching nor scattering changes displayed kinetics sufficiently fast to be taken as a direct expression of internal thylakoid acidificati on in intact leaves. This conclusion is drawn from comparative measurements of proton-uptake, as reflected by CO2-solubilization upon light-induced stroma alkalization, and of chlorophyll luminescence. Both, the initial CO2 - gulp and the pH-dependent luminescence rise were found to clearly precede the development of energy-dependent quenching.

scholarly journals Growth under Fluctuating Light Reveals Large Trait Variation in a Panel of Arabidopsis Accessions

Plants ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 316 ◽  
Author(s):  
Elias Kaiser ◽  
Dirk Walther ◽  
Ute Armbruster
Keyword(s):  
Photosystem Ii ◽  
Chemical Potential ◽  
Genomic Variation ◽  
Operating Efficiency ◽  
Photochemical Quenching ◽  
Low Light ◽  
Trait Variation ◽  
Light Regimes ◽  
Fluctuating Light ◽  
Non Photochemical Quenching

The capacity of photoautotrophs to fix carbon depends on the efficiency of the conversion of light energy into chemical potential by photosynthesis. In nature, light input into photosynthesis can change very rapidly and dramatically. To analyze how genetic variation in Arabidopsis thaliana affects photosynthesis and growth under dynamic light conditions, 36 randomly chosen natural accessions were grown under uniform and fluctuating light intensities. After 14 days of growth under uniform or fluctuating light regimes, maximum photosystem II quantum efficiency (Fv/Fm) was determined, photosystem II operating efficiency (ΦPSII) and non-photochemical quenching (NPQ) were measured in low light, and projected leaf area (PLA) as well as the number of visible leaves were estimated. Our data show that ΦPSII and PLA were decreased and NPQ was increased, while Fv/Fm and number of visible leaves were unaffected, in most accessions grown under fluctuating compared to uniform light. There were large changes between accessions for most of these parameters, which, however, were not correlated with genomic variation. Fast growing accessions under uniform light showed the largest growth reductions under fluctuating light, which correlated strongly with a reduction in ΦPSII, suggesting that, under fluctuating light, photosynthesis controls growth and not vice versa.

Sign in / Sign up

Export Citation Format

Share Document