Factors determining the fluorescence yield of fucoxanthin-chlorophyll complexes (FCP) involved in non-photochemical quenching in diatoms

Gundermann, Kathi; Büchel, Claudia

doi:10.1016/j.bbabio.2012.03.008

Cited by 75 publications

(64 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In C. gracilis, the FCPo complex showed a lower energy level of the final acceptor state compared with the FCPt complex, which was consistent with previous results [15]. In contrast, in C. meneghiniana, the FCPt form showed a lower energy level of the final acceptor state compared with the FCPo complex, which was also consistent with previous results [31].…”

Section: Spectral Properties Of Fcp Complexes Isolated From Diatomssupporting

confidence: 93%

Regulation of excitation energy transfer in diatom PSII dimer: How does it change the destination of excitation energy?

Yokono

Nagao

Tomo

et al. 2015

Biochimica et Biophysica Acta (BBA) - Bioenergetics

View full text Add to dashboard Cite

Energy transfer dynamics in dimeric photosystem II (PSII) complexes isolated from four diatoms, Chaetoceros gracilis, Cyclotella meneghiniana, Thalassiosira pseudonana, and Phaeodactylum tricornutum, are examined. Time-resolved fluorescence measurements were conducted in the range of 0-80ns. Delayed fluorescence spectra showed a clear difference between PSII monomer and PSII dimer isolated from the four diatoms. The difference can be interpreted as reflecting suppressed energy transfer between PSII monomers in the PSII dimer for efficient energy trapping at the reaction center. The observation was especially prominent in C. gracilis and T. pseudonana. The pathways seem to be suppressed under a low pH condition in isolated PSII complexes from C. gracilis, and excitation energy may be quenched with fucoxanthin chlorophyll a/c-binding protein (FCP) that was closely associated with PSII in C. gracilis. The energy transfer between PSII monomers in the PSII dimer may play a role in excitation energy regulation in diatoms.

show abstract

Section: Spectral Properties Of Fcp Complexes Isolated From Diatomssupporting

confidence: 93%

Regulation of excitation energy transfer in diatom PSII dimer: How does it change the destination of excitation energy?

Yokono

Nagao

Tomo

et al. 2015

Biochimica et Biophysica Acta (BBA) - Bioenergetics

View full text Add to dashboard Cite

show abstract

“…Upon DpHdriven de-epoxidation of Dd and protonation of some antenna proteins (presumably Lhcx), PS2 antenna efficiently quenches excited states of chlorophyll a (Lepetit et al 2013;Goss and Lepetit 2015). Additionally NPQ might be accompanied by partial antenna detachment, which may also contribute to overall NPQ through quenching in the detached FCP oligomers (Miloslavina et al 2009;Gundermann and Büchel 2012). However, despite significant progress in recent years, the molecular mechanisms of NPQ in a vast majority of algae are not yet established.…”

Section: Introductionmentioning

confidence: 93%

Energy dissipation pathways in Photosystem 2 of the diatom, Phaeodactylum tricornutum, under high-light conditions

Kuzminov

Gorbunov

2015

Photosynth Res

View full text Add to dashboard Cite

To prevent photooxidative damage under supraoptimal light, photosynthetic organisms evolved mechanisms to thermally dissipate excess absorbed energy, known as non-photochemical quenching (NPQ). Here we quantify NPQ-induced alterations in light-harvesting processes and photochemical reactions in Photosystem 2 (PS2) in the pennate diatom Phaeodactylum tricornutum. Using a combination of picosecond lifetime analysis and variable fluorescence technique, we examined the dynamics of NPQ activation upon transition from dark to high light. Our analysis revealed that NPQ activation starts with a 2-3-fold increase in the rate constant of non-radiative charge recombination in the reaction center (RC); however, this increase is compensated with a proportional increase in the rate constant of back reactions. The resulting alterations in photochemical processes in PS2 RC do not contribute directly to quenching of antenna excitons by the RC, but favor non-radiative dissipation pathways within the RC, reducing the yields of spin conversion of the RC chlorophyll to the triplet state. The NPQ-induced changes in the RC are followed by a gradual ~ 2.5-fold increase in the yields of thermal dissipation in light-harvesting complexes. Our data suggest that thermal dissipation in light-harvesting complexes is the major sink for NPQ; RCs are not directly involved in the NPQ process, but could contribute to photoprotection via reduction in the probability of (3)Chl formation.

show abstract

“…Liposome Preparation and Incorporation of LHCII-For liposome preparation we used a modified protocol from Gundermann and Büchel (46). The thylakoid lipids monogalactosyl diacylglycerol, digalactosyl diacylglycerol, sulfoquinovosyl diacylglycerols, phosphatidylglycerol, and phosphatidylcholine were purchased from Larodan Fine Chemicals (Malmö, Sweden), already dissolved in chloroform.…”

Section: Methodsmentioning

confidence: 99%

Light-harvesting Complexes (LHCs) Cluster Spontaneously in Membrane Environment Leading to Shortening of Their Excited State Lifetimes

Natali

Gruber

Dietzel

et al. 2016

Journal of Biological Chemistry

View full text Add to dashboard Cite

The light reactions of photosynthesis, which include lightharvesting and charge separation, take place in the amphiphilic environment of the thylakoid membrane. The light-harvesting complex II (LHCII) is the main responsible for light absorption in plants and green algae and is involved in photoprotective mechanisms that regulate the amount of excited states in the membrane. The dual function of LHCII has been extensively studied in detergent micelles, but recent results have indicated that the properties of this complex differ in a lipid environment. In this work we checked these suggestions by studying LHCII in liposomes. By combining bulk and single molecule measurements, we monitored the fluorescence characteristics of liposomes containing single complexes up to densely packed proteoliposomes. We show that the natural lipid environment per se does not alter the properties of LHCII, which for single complexes remain very similar to that in detergent. However, we show that LHCII has the strong tendency to cluster in the membrane and that protein interactions and the extent of crowding modulate the lifetimes of the excited state in the membrane. Finally, the presence of LHCII monomers at low concentrations of complexes per liposome is discussed.Photosynthetic organisms evolved the capacity to harvest the energy of solar radiation and store it into chemical compounds. In vascular plants and green algae, sunlight is absorbed by a series of membrane proteins called light-harvesting complexes (LHC).3 The most abundant of these pigment-protein complexes is LHCII. The LHCs have a dual function; in low light conditions they absorb solar energy and efficiently transfer the excitation energy to the reaction center, and in high light they additionally play a role in photoprotection by dissipating the energy absorbed in excess as heat (1, 2). This last process called non-photochemical quenching (NPQ) leads to a decrease of the excited state lifetime of chlorophyll a (Chl a), limiting the possibility of Chl triplet formation and thus the production of singlet oxygen (3). The fast, on the timescale of seconds, and fully reversible part of NPQ is called qE. This mechanism is triggered by the acidification of the lumenal space of the thylakoids, which activates PsbS (4) and LhcSR (5), the proteins responsible for NPQ in plants and green algae, respectively, and the violaxanthin de-epoxidase, which converts violaxanthin into zeaxanthin (for reviews, see Refs. 6 and 7). Although the precise molecular mechanism of quenching has not been fully elucidated yet, a prominent idea discussed in literature is that NPQ is regulated via conformational changes of LHCII. Those changes could be correlated to, or even caused by, LHCII aggregation (8, 9). It was observed that low pH and zeaxanthin, both occurring in high light, enhance LHCII aggregation (10). Aggregation of LHCII in vitro is accompanied by a decrease of the Chl a fluorescence yield, indicating an increased rate of energy dissipation (9, 11). The generation of new quenching sit...

show abstract

Factors determining the fluorescence yield of fucoxanthin-chlorophyll complexes (FCP) involved in non-photochemical quenching in diatoms

Cited by 75 publications

References 34 publications

Regulation of excitation energy transfer in diatom PSII dimer: How does it change the destination of excitation energy?

Regulation of excitation energy transfer in diatom PSII dimer: How does it change the destination of excitation energy?

Energy dissipation pathways in Photosystem 2 of the diatom, Phaeodactylum tricornutum, under high-light conditions

Light-harvesting Complexes (LHCs) Cluster Spontaneously in Membrane Environment Leading to Shortening of Their Excited State Lifetimes

Contact Info

Product

Resources

About