A5043965678- Photosynthetic Processes and Mechanisms
- Photoreceptor and optogenetics research
- Light effects on plants
- Spectroscopy and Quantum Chemical Studies
- Mitochondrial Function and Pathology
- Electrochemical Analysis and Applications
- Antioxidant Activity and Oxidative Stress
- Plant Stress Responses and Tolerance
- Advanced Fluorescence Microscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Plasmonic and Surface Plasmon Research
- Remote Sensing in Agriculture
- Water Quality Monitoring and Analysis
- Porphyrin and Phthalocyanine Chemistry
- Advanced Chemical Physics Studies
- Strong Light-Matter Interactions
- Water resources management and optimization
- Algal biology and biofuel production
- Water-Energy-Food Nexus Studies
- Greenhouse Technology and Climate Control
- ATP Synthase and ATPases Research
- Plant Water Relations and Carbon Dynamics
- Molecular Junctions and Nanostructures
- Climate change impacts on agriculture
Wageningen University & Research
2016-2025
Vrije Universiteit Amsterdam
2011-2019
Institute of Photonic Sciences
2014-2016
University of Groningen
2008-2012
Molecular Research Institute
2009
The mechanisms underlying the wavelength dependence of quantum yield for CO(2) fixation (α) and its acclimation to growth-light spectrum are quantitatively addressed, combining in vivo physiological vitro molecular methods. Cucumber (Cucumis sativus) was grown under an artificial sunlight spectrum, shade light blue light, photosystem I (PSI) II (PSII) electron transport α were simultaneously measured at 20 different wavelengths. excitation balance calculated from both these data composition...
LHCII, the most abundant membrane protein on earth, is major light-harvesting complex of plants. It generally accepted that LHCII associated with Photosystem II and only as a short-term response to overexcitation PSII subset moves I, triggered by its phosphorylation (state1 state2 transition). However, here we show in natural light conditions serves an antenna both I it quantitatively demonstrated this required achieve excitation balance between two photosystems. This allows for acclimation...
Time‐resolved fluorescence on oligomers of the main light‐harvesting complex from higher plants indicate that in vitro oligomerization leads to formation a weakly coupled inter‐trimer chlorophyll–chlorophyll (Chl) exciton state which converts tens ps into is spectrally broad and has strongly far‐red enhanced spectrum. Both its lifetime spectrum show striking similarity with 400 component appearing intact leaves Arabidopsis when non‐photochemical quenching (NPQ) induced. The components high...
The energy dissipation mechanism in oligomers of the major light-harvesting complex II (LHC II) from Arabidopsis thaliana mutants npq1 and npq2, zeaxanthin-deficient zeaxanthin-enriched, respectively, has been studied by femtosecond transient absorption. kinetics obtained at different excitation intensities are compared implications singlet-singlet annihilation discussed. Under conditions where is absent, two types LHC show distributive biexponential (bimodal) with lifetimes approximately...
We have studied thylakoid membranes of Arabidopsis thaliana acclimated to different light conditions and related protein composition excitation energy transfer trapping kinetics in Photosystem II (PSII). In high light: the plants reduced amounts antenna complexes LHCII CP24, overall time PSII is only ∼180 ps, quantum efficiency reaches a value 91%. low upregulated, lifetime becomes ∼310 decreases 84%. This difference largely caused by slower migration reaction centers low-light due trimers...
The nature of the highly efficient energy transfer in photosynthetic light-harvesting complexes is a subject intense research. Unfortunately, low fluorescence efficiency and limited photostability hampers study individual at ambient conditions. Here we demonstrate an over 500-fold enhancement complex 2 (LH2) single-molecule level by coupling to gold nanoantenna. resonant antenna produces excitation circa 100 times lifetime shortening ~\n20 ps. radiative rate results 5.5-fold-improved quantum...
The outer antenna of higher-plant PSI (Photosystem I) is composed four complexes [Lhc (light-harvesting complex) a1-Lhca4] belonging to the light-harvesting protein family. Difficulties in their purification have so far prevented determination properties and most knowledge about Lhcas has been obtained from study vitro reconstituted antennas. In present we were able purify native complexes, showing that Lhca2/3 Lhca1/4 form two functional heterodimers. Both dimers show red-fluorescence...
The light-harvesting complexes of photosystem I and II (Lhcas Lhcbs) plants display a high structural homology similar pigment content organization. Yet, the spectroscopic properties these complexes, accordingly their functionality, differ substantially. This difference is primarily due to charge-transfer (CT) character chlorophyll dimer in all Lhcas, which mixes with excitonic states whereas this CT generally absent Lhcbs. By means single-molecule spectroscopy near room temperature, we...
In this work, Photosystem I supercomplexes have been purified from Lhca-deficient lines of Arabidopsis thaliana using a mild detergent treatment that does not induce loss outer antennas. The complexes studied by integrating biochemical analysis with electron microscopy. This allows the direct correlation changes in protein content supramolecular structure to get information about position individual Lhca subunits, association antenna core, and influence subunits on stability system. only two...
Plants are exposed to continuous changes in light quality and quantity that challenge the performance of photosynthetic apparatus have evolved a series mechanisms face this challenge. In work, we studied state transitions, process redistributes excitation pressure between photosystems I II (PSI/PSII) by reversible association LHCII, major antenna complex higher plants, with either one them upon phosphorylation/dephosphorylation. By combining biochemical analysis electron microscopy, effect...
Photosystem I (PSI) is an essential component of photosynthetic membranes. Despite the high sequence and structural homologies, its absorption properties differ substantially in algae, plants cyanobacteria. In particular it characterized by presence low-energy chlorophylls (red forms), number energy which vary different organisms. The PSI-LHCI (PSI-light harvesting complex I) green alga Chlamydomonas reinhardtii (C.r.) significantly larger than that plants, containing five additional...
Light absorbed by chlorophylls of Photosystems II and I drives oxygenic photosynthesis. Light-harvesting complexes increase the absorption cross-section these photosystems. Furthermore, play a central role in photoprotection dissipating excess light energy an inducible regulated fashion. In higher plants, main light-harvesting complex is trimeric LHCII. this work, we used CRISPR/Cas9 to knockout five genes encoding LHCB1, which major component absence accumulation other LHCII isoforms was...
Photosynthetic light-harvesting antennae are pigment-binding proteins that perform one of the most fundamental tasks on Earth, capturing light and transferring energy enables life in our biosphere. Adaptation to different environments led evolution an astonishing diversity systems. At same time, several strategies have been developed optimize input into photosynthetic membranes response fluctuating conditions. The basic feature these prompt responses is dynamic nature antenna complexes,...
CP24 is a minor antenna complex of Photosystem II, which specific for land plants. It has been proposed that this involved in the process excess energy dissipation, protects plants from photodamage high light conditions. Here, we have investigated functional architecture complex, integrating mutation analysis with time-resolved spectroscopy. A comprehensive picture obtained about nature, spectroscopic properties, and role quenching solution pigments individual binding sites. The lowest...
The transfer of electronic charge in the reaction center Photosystem II is one key building blocks conversion sunlight energy into chemical within cascade photosynthetic reactions. Since dynamics mixed with dynamics, an effective tool for direct resolution separation still missing. Here, we use experimental two-dimensional optical photon echo spectroscopy combination theoretical calculation to resolve its signature. A global fitting analysis allows us clearly and directly identify a decay...
Cyanobacteria use chlorophyll and phycobiliproteins to harvest light. The resulting excitation energy is delivered reaction centers (RCs), where photochemistry starts. relative amounts of arriving at the RCs photosystem I (PSI) II (PSII) depend on spectral composition To balance excitations in both photosystems, cyanobacteria perform state transitions equilibrate energy. They go if PSI preferentially excited, for example after illumination with blue light (light I), green-orange II) or dark...