title: Is It Beneficial for the Major Photosynthetic Antenna Complex of Plants To Form Trimers?
abstract: The process of primary electric charge separation in photosynthesis takes place in the reaction centers, but photosynthesis can operate efficiently and fluently due to the activity of several pigment-protein complexes called antenna, which absorb light quanta and transfer electronic excitations toward the reaction centers. LHCII is the major photosynthetic pigment-protein antenna complex of plants and appears in the trimeric form. Several recent reports point to trimeric organization of LHCII as a key factor responsible for the chloroplast architecture via stabilization of granal organization of the thylakoid membranes. In the present work, we address the question of whether such an organization could also directly influence the antenna properties of this pigment-protein complex. Chlorophyll fluorescence analysis reveals that excitation energy transfer in LHCII is substantially more efficient in trimers and dissipative energy losses are higher in monomers. It could be concluded that trimers are exceptionally well suited to perform the antenna function. Possibility of fine regulation of the photosynthetic antenna function via the LHCII trimer-monomer transition is also discussed, based on the fluorescence lifetime analysis in a single chloroplast.
authors.affiliation: †Department of Biophysics, Institute of Physics, Maria Curie-Skłodowska University, Lublin 20-031, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Janik
authors.affiliation: †Department of Biophysics, Institute of Physics, Maria Curie-Skłodowska University, Lublin 20-031, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Bednarska
authors.affiliation: †Department of Biophysics, Institute of Physics, Maria Curie-Skłodowska University, Lublin 20-031, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Zubik
authors.affiliation: †Department of Biophysics, Institute of Physics, Maria Curie-Skłodowska University, Lublin 20-031, Poland.|‡Faculty of Pharmacy, Medical University, Lublin 20-093, Poland.
authors.forename: Karol
authors.initials: K
authors.lastname: Sowinski
authors.affiliation: †Department of Biophysics, Institute of Physics, Maria Curie-Skłodowska University, Lublin 20-031, Poland.
authors.forename: Rafal
authors.initials: R
authors.lastname: Luchowski
authors.affiliation: †Department of Biophysics, Institute of Physics, Maria Curie-Skłodowska University, Lublin 20-031, Poland.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Grudzinski
authors.affiliation: †Department of Biophysics, Institute of Physics, Maria Curie-Skłodowska University, Lublin 20-031, Poland.
authors.forename: Wieslaw I
authors.initials: WI
authors.lastname: Gruszecki
mesh_terms: D002736:Chloroplasts / Q000737:chemistry; D004586:Electrophoresis; D007700:Kinetics; D008856:Microscopy, Fluorescence; D045332:Photosystem II Protein Complex / Q000737:chemistry* / Q000302:isolation & purification; D013057:Spectrum Analysis; D018724:Spinacia oleracea
chemical_list: D045332:Photosystem II Protein Complex