Accumulation of monomer and dimer photosystem (PS) II reaction center core complexes has been analyzed by two-dimensional Blue-native/SDS-PAGE in Synechocystis PCC 6803 wild type mutant strains lacking genes psbA, psbB, psbC, psbDIC/DII, or the psbEFLJ operon. In vivo pulse-chase radiolabeling experiments revealed that cells assembled PSII precomplexes only. DeltapsbC DeltapsbB, assembly cores CP43 was detected, respectively. DeltapsbA, protein subunits CP43, CP47, D2, cytochrome b559 were...

The role of the slr2034 (ycf48) gene product in assembly and repair photosystem II (PSII) has been studied cyanobacterium Synechocystis PCC 6803. YCF48 (HCF136) is involved Arabidopsis thaliana PSII reaction center (RC) complexes but its mode action unclear. We show here that a component two cyanobacterial RC-like vivo absent larger core complexes. Interruption ycf48 slowed formation wild type, as judged from pulse-labeling experiments, caused decrease final level type marked reduction...

Abstract The role of the Psb28 protein in structure and function photosystem II (PSII) complex has been studied cyanobacterium Synechocystis sp. PCC 6803. was localized membrane fraction and, whereas most detected as an unassembled protein, a small portion found PSII core lacking CP43 antenna (RC47). association with RC47 further confirmed by preferential isolation from strain containing histidine-tagged derivative using nickel-affinity chromatography. However, affinity-purified also...

Macromolecular membrane assemblies of chlorophyll-protein complexes efficiently harvest and trap light energy for photosynthesis. To investigate the delivery chlorophylls to newly synthesized photosystem apoproteins, a terminal enzyme chlorophyll biosynthesis, synthase (ChlG), was tagged in cyanobacterium Synechocystis PCC 6803 (Synechocystis) used as bait pull-down experiments. We retrieved an enzymatically active complex comprising ChlG high-light-inducible protein HliD, which associates...

Abstract Efficient assembly and repair of the oxygen-evolving photosystem II (PSII) complex is vital for maintaining photosynthetic activity in plants, algae, cyanobacteria. How chlorophyll delivered to PSII during how vulnerable complexes are protected from photodamage unknown. Here, we identify a β-carotene binding protein cyanobacterium Synechocystis PCC 6803 important formation D1/D2 reaction center complex. It composed putative short-chain dehydrogenase/reductase Ycf39, encoded by...

The cyanobacterium Synechocystis sp. PCC 6803 contains four members of the FtsH protease family. One these, (slr0228), has been implicated recently in repair photodamaged photosystem II (PSII) complexes. We have demonstrated here, using a combination blue native PAGE, radiolabeling, and immunoblotting, that (slr0228) is required for selective replacement D1 reaction center subunit both wild type PSII complexes subcomplexes lacking chlorophyll a-binding CP43. To test whether more general role...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTComparison of psbO and psbH deletion mutants Synechocystis PCC 6803 indicates that degradation D1 protein is regulated by the QB site dependent on synthesisJosef Komenda James BarberCite this: Biochemistry 1995, 34, 29, 9625–9631Publication Date (Print):July 25, 1995Publication History Published online1 May 2002Published inissue 25 July 1995https://pubs.acs.org/doi/10.1021/bi00029a040https://doi.org/10.1021/bi00029a040research-articleACS...

Abstract We have investigated the location of Psb27 protein and its role in photosystem (PS) II biogenesis cyanobacterium Synechocystis sp. PCC 6803. Native gel electrophoresis revealed that was present mainly monomeric PSII core complexes but also smaller amounts dimeric complexes, large supercomplexes, unassembled fraction. conclude from analysis assembly mutants isolated histidine-tagged subcomplexes associates with “unassembled” CP43 complex, as well larger containing CP43, possibly...

Biochemical characterization of intermediates involved in the assembly oxygen-evolving Photosystem II (PSII) complex is hampered by their low abundance membrane. Using cyanobacterium Synechocystis sp. PCC 6803, we describe here isolation CP47 and CP43 subunits, which, during biogenesis, attach to a reaction center containing D1, D2, cytochrome b(559), with binding first. Our experimental approach combination His tagging, use D1 deletion mutant that blocks PSII at an early stage, and, case...

Cyanobacteria acclimate to high-light conditions by adjusting photosystem stoichiometry through a decrease of I (PSI) abundance in thylakoid membranes. As PSI complexes bind the majority chlorophyll (Chl) cyanobacterial cells, it is accepted that mechanism controlling level/synthesis tightly associated with Chl biosynthetic pathway. However, how distributed photosystems under different light remains unknown. Using radioactive labeling 35S and 14C combined native/two-dimensional...

Abstract A biosensor for the detection of triazine‐ and phenylurea‐type herbicides was constructed using isolated Photosystem II (PS II) complexes as a biosensing element. PSII from thermophilic cyanobacterium Synechococcus elongatus immobilized on surface screen‐printed sensor composed graphite working electrode Ag/AgCl reference deposited polymeric substrate. The mounted in flow microcell with illumination. principle based fact that selectively block electron transport activity...

Different species of microalgae show a wide range susceptibility to ultraviolet‐B (UV‐B) radiation. To identify factors responsible for the UV‐B tolerance some algae, we compared 8 that are highly tolerant susceptible. The contained substantial amounts an acetolysis‐resistant residue. residue consists sporopollenin, biopolymer variable chemical composition occurs in algal cell walls and absorbs susceptible little or no sporopollenin. We propose sporopollenin provides protection by screening...

The cyanobacterial small CAB-like proteins (SCPs) consist of one-helix that resemble transmembrane regions the light-harvesting plants. To determine whether these are associated with protein complexes in thylakoid membrane, an abundant member SCP family, ScpD, was marked a His tag, and co-isolating His-tagged ScpD were identified. These included major Photosystem (PS) II components as well FtsH, which is involved degradation PSII complex. ascertain specific interaction between complex,...

Action of reactive oxygen species (ROS) on the isolated D1 protein, a key component Photosystem II (PSII) complex, was studied and compared with effect high irradiance this protein in mildly solubilized photosynthetic membranes cells cyanobacterium Synechocystis. Whereas singlet caused mainly modification reflected by shift its electrophoretic mobility, action hydrogen peroxide superoxide resulted generation specific fragments. Hydroxyl radicals as most ROS induced fast disappearance...

The selective replacement of photodamaged D1 protein within the multisubunit photosystem II (PSII) complex is an important photoprotective mechanism in chloroplasts and cyanobacteria. FtsH proteases are involved at early stage degradation, but it remains unclear how damaged subunit recognized, degraded, replaced. To test role N-terminal region PSII biogenesis repair, we have constructed mutants cyanobacterium Synechocystis sp PCC 6803 that truncated exposed N terminus. Removal 5 or 10...

Abstract The involvement of the PsbI protein in assembly and repair photosystem II (PSII) complex has been studied cyanobacterium Synechocystis sp. PCC 6803. Analysis PSII complexes wild-type strain showed that was present dimeric monomeric core complexes, lacking CP43, reaction center containing D1, D2, cytochrome b-559. In addition, immunoprecipitation experiments use a histidine-tagged derivative have revealed presence thylakoid membrane either precursor or mature forms D1. psbI deletion...

Gun4 is a porphyrin-binding protein that activates magnesium chelatase, multimeric enzyme catalyzing the first committed step in chlorophyll biosynthesis. In plants, GUN4 has been implicated plastid-to-nucleus retrograde signaling processes coordinate both photosystem II and I nuclear gene expression with chloroplast function. this work we present functional analysis of from cyanobacterium Synechocystis sp. PCC 6803. Affinity co-purification FLAG-tagged ChlH subunit chelatase confirmed...

The crtB gene of Synechocystis sp. PCC 6803, encoding phytoene synthase, was inactivated in the ΔcrtH mutant to generate a carotenoidless ΔcrtH/B double mutant. cells were used because they had better transformability than wild-type cells, most probably due their adaptation partial carotenoid deficiency. Cells light sensitive and could grow only under light-activated heterotrophic growth conditions presence glucose. Carotenoid deficiency did not significantly affect cellular content...