title: Psb27, a cyanobacterial lipoprotein, is involved in the repair cycle of photosystem II.
abstract: Photosystem II (PSII) performs one of the key reactions on our planet: the light-driven oxidation of water. This fundamental but very complex process requires PSII to act in a highly coordinated fashion. Despite detailed structural information on the fully assembled PSII complex, the dynamic aspects of formation, processing, turnover, and degradation of PSII with at least 19 subunits and various cofactors are still not fully understood. Transient complexes are especially difficult to characterize due to low abundance, potential heterogeneity, and instability. Here, we show that Psb27 is involved in the assembly of the water-splitting site of PSII and in the turnover of the complex. Psb27 is a bacterial lipoprotein with a specific lipid modification as shown by matrix-assisted laser-desorption ionization time of flight mass spectrometry. The combination of HPLC purification of four different PSII subcomplexes and (15)N pulse label experiments revealed that lipoprotein Psb27 is part of a preassembled PSII subcomplex that represents a distinct intermediate in the repair cycle of PSII.
authors.affiliation: Plant Biochemistry, Ruhr-University Bochum, D-44780 Bochum, Germany.
authors.forename: Marc M
authors.initials: MM
authors.lastname: Nowaczyk
authors.forename: Romano
authors.initials: R
authors.lastname: Hebeler
authors.forename: Eberhard
authors.initials: E
authors.lastname: Schlodder
authors.forename: Helmut E
authors.initials: HE
authors.lastname: Meyer
authors.forename: Bettina
authors.initials: B
authors.lastname: Warscheid
authors.forename: Matthias
authors.initials: M
authors.lastname: Rögner
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D002614:Chelating Agents / Q000378:metabolism; D002852:Chromatography, Ion Exchange; D000458:Cyanobacteria / Q000378:metabolism* / Q000528:radiation effects; D004591:Electrophoresis, Polyacrylamide Gel; D006639:Histidine; D008027:Light; D008074:Lipoproteins / Q000737:chemistry / Q000378:metabolism*; D013058:Mass Spectrometry; D008954:Models, Biological; D008969:Molecular Sequence Data; D009532:Nickel / Q000302:isolation & purification; D009587:Nitrogen Isotopes; D009842:Oligopeptides; D010455:Peptides / Q000737:chemistry; D045332:Photosystem II Protein Complex / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000528:radiation effects; D021122:Protein Subunits / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D002614:Chelating Agents; C471213:His-His-His-His-His-His; D008074:Lipoproteins; D009587:Nitrogen Isotopes; D009842:Oligopeptides; D010455:Peptides; D045332:Photosystem II Protein Complex; D021122:Protein Subunits; D006639:Histidine; D009532:Nickel