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Photosynthetic Reaction Center Complex ProteinsRhodobacter sphaeroidesLight-Harvesting Protein ComplexesBacteriochlorophyllsRhodopseudomonasPhotosystem II Protein ComplexElectron TransportPhotosynthesisChlorophyllPheophytinsPhotosystem I Protein ComplexLightCyanobacteriaCytochromes c2ChlorobiQuinonesSpectrophotometryEnergy TransferSpinacia oleraceaRhodobacterBacterial ProteinsProteobacteriaOxidation-ReductionAcidiphiliumHyphomicrobiaceaeElectronsPhotochemistryBacterial ChromatophoresMolecular Sequence DataChlorobiumUbiquinoneAmino Acid SequenceEuglenaKineticsNonheme Iron ProteinsRhodospirillaceaeDiuronSpectrum AnalysisBacteriochlorophyll AProtonsChromatiaceaeModels, MolecularRhodobacter capsulatusCytochrome c GroupRhodovulumProtein ConformationElectrochemistryChromatiumThermodynamicsElectron Spin Resonance SpectroscopyElectrophoresis, Polyacrylamide GelModels, ChemicalIron-Sulfur ProteinsCytochromesStatic ElectricityBenzoquinonesNuclear Pore Complex ProteinsCrystallography, X-RayHydrogen BondingHemeBinding SitesBacteriaMutagenesis, Site-DirectedMembrane ProteinsTemperatureDimethylaminesChloroplastsWaterModels, TheoreticalMolecular StructureHydrogen-Ion ConcentrationMacromolecular SubstancesGenes, BacterialBase Sequence
Photosynthetic Reaction Center Complex Proteins: Protein complexes that take part in the process of PHOTOSYNTHESIS. They are located within the THYLAKOID MEMBRANES of plant CHLOROPLASTS and a variety of structures in more primitive organisms. There are two major complexes involved in the photosynthetic process called PHOTOSYSTEM I and PHOTOSYSTEM II.Rhodobacter sphaeroides: Spherical phototrophic bacteria found in mud and stagnant water exposed to light.Light-Harvesting Protein Complexes: Complexes containing CHLOROPHYLL and other photosensitive molecules. They serve to capture energy in the form of PHOTONS and are generally found as components of the PHOTOSYSTEM I PROTEIN COMPLEX or the PHOTOSYSTEM II PROTEIN COMPLEX.Bacteriochlorophylls: Pyrrole containing pigments found in photosynthetic bacteria.Rhodopseudomonas: A genus of gram-negative, rod-shaped, phototrophic bacteria found in aquatic environments. Internal photosynthetic membranes are present as lamellae underlying the cytoplasmic membrane.Photosystem II Protein Complex: A large multisubunit protein complex found in the THYLAKOID MEMBRANE. It uses light energy derived from LIGHT-HARVESTING PROTEIN COMPLEXES to catalyze the splitting of WATER into DIOXYGEN and of reducing equivalents of HYDROGEN.Electron Transport: The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)Photosynthesis: The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)Chlorophyll: Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.Pheophytins: Chlorophylls from which the magnesium has been removed by treatment with weak acid.Photosystem I Protein Complex: A large multisubunit protein complex that is found in the THYLAKOID MEMBRANE. It uses light energy derived from LIGHT-HARVESTING PROTEIN COMPLEXES to drive electron transfer reactions that result in either the reduction of NADP to NADPH or the transport of PROTONS across the membrane.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Cyanobacteria: A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.Cytochromes c2: Type C cytochromes that are small (12-14 kD) single-heme proteins. They function as mobile electron carriers between membrane-bound enzymes in photosynthetic BACTERIA.Chlorobi: A phylum of anoxygenic, phototrophic bacteria including the family Chlorobiaceae. They occur in aquatic sediments, sulfur springs, and hot springs and utilize reduced sulfur compounds instead of oxygen.Quinones: Hydrocarbon rings which contain two ketone moieties in any position. They can be substituted in any position except at the ketone groups.Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.Energy Transfer: The transfer of energy of a given form among different scales of motion. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed). It includes the transfer of kinetic energy and the transfer of chemical energy. The transfer of chemical energy from one molecule to another depends on proximity of molecules so it is often used as in techniques to measure distance such as the use of FORSTER RESONANCE ENERGY TRANSFER.Spinacia oleracea: A widely cultivated plant, native to Asia, having succulent, edible leaves eaten as a vegetable. (From American Heritage Dictionary, 1982)Rhodobacter: A genus of gram-negative bacteria widely distributed in fresh water as well as marine and hypersaline habitats.Bacterial Proteins: Proteins found in any species of bacterium.Proteobacteria: A phylum of bacteria consisting of the purple bacteria and their relatives which form a branch of the eubacterial tree. This group of predominantly gram-negative bacteria is classified based on homology of equivalent nucleotide sequences of 16S ribosomal RNA or by hybridization of ribosomal RNA or DNA with 16S and 23S ribosomal RNA.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Acidiphilium: A genus in the family ACETOBACTERACEAE consisting of chemoorganotrophic, straight rods with rounded ends. They are aerobic and acidophilic.Hyphomicrobiaceae: A family in the order Rhizobiales, class ALPHAPROTEOBACTERIA comprised of many genera of budding or appendaged bacteria.Electrons: Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.PhotochemistryBacterial Chromatophores: Organelles of phototrophic bacteria which contain photosynthetic pigments and which are formed from an invagination of the cytoplasmic membrane.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Chlorobium: A genus of phototrophic, obligately anaerobic bacteria in the family Chlorobiaceae. They are found in hydrogen sulfide-containing mud and water environments.Ubiquinone: A lipid-soluble benzoquinone which is involved in ELECTRON TRANSPORT in mitochondrial preparations. The compound occurs in the majority of aerobic organisms, from bacteria to higher plants and animals.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Euglena: A genus of EUKARYOTES, in the phylum EUGLENIDA, found mostly in stagnant water. Characteristics include a pellicle usually marked by spiral or longitudinal striations.Kinetics: The rate dynamics in chemical or physical systems.Nonheme Iron Proteins: Proteins, usually acting in oxidation-reduction reactions, containing iron but no porphyrin groups. (Lehninger, Principles of Biochemistry, 1993, pG-10)Rhodospirillaceae: A family of phototrophic bacteria, in the order Rhodospirillales, isolated from stagnant water and mud.Diuron: A pre-emergent herbicide.Spectrum Analysis: The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Bacteriochlorophyll A: A specific bacteriochlorophyll that is similar in structure to chlorophyll a.Protons: Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.Chromatiaceae: A family of phototrophic purple sulfur bacteria that deposit globules of elemental sulfur inside their cells. They are found in diverse aquatic environments.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Rhodobacter capsulatus: Non-pathogenic ovoid to rod-shaped bacteria that are widely distributed and found in fresh water as well as marine and hypersaline habitats.Cytochrome c Group: A group of cytochromes with covalent thioether linkages between either or both of the vinyl side chains of protoheme and the protein. (Enzyme Nomenclature, 1992, p539)Rhodovulum: A genus of facultatively or obligately anaerobic marine phototrophic bacteria, in the family RHODOBACTERACEAE.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Electrochemistry: The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.Chromatium: A genus of gram-negative, ovoid to rod-shaped bacteria that is phototrophic. All species use ammonia as a nitrogen source. Some strains are found only in sulfide-containing freshwater habitats exposed to light while others may occur in marine, estuarine, and freshwater environments.Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Electron Spin Resonance Spectroscopy: A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Iron-Sulfur Proteins: A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.Cytochromes: Hemeproteins whose characteristic mode of action involves transfer of reducing equivalents which are associated with a reversible change in oxidation state of the prosthetic group. Formally, this redox change involves a single-electron, reversible equilibrium between the Fe(II) and Fe(III) states of the central iron atom (From Enzyme Nomenclature, 1992, p539). The various cytochrome subclasses are organized by the type of HEME and by the wavelength range of their reduced alpha-absorption bands.Static Electricity: The accumulation of an electric charge on a objectBenzoquinones: Benzene rings which contain two ketone moieties in any position. They can be substituted in any position except at the ketone groups.Nuclear Pore Complex Proteins: Proteins that form the structure of the NUCLEAR PORE. They are involved in active, facilitated and passive transport of molecules in and out of the CELL NUCLEUS.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Hydrogen Bonding: A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.Heme: The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Bacteria: One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.DimethylaminesChloroplasts: Plant cell inclusion bodies that contain the photosynthetic pigment CHLOROPHYLL, which is associated with the membrane of THYLAKOIDS. Chloroplasts occur in cells of leaves and young stems of plants. They are also found in some forms of PHYTOPLANKTON such as HAPTOPHYTA; DINOFLAGELLATES; DIATOMS; and CRYPTOPHYTA.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Models, Theoretical: Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Macromolecular Substances: Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.Genes, Bacterial: The functional hereditary units of BACTERIA.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

Role of a novel photosystem II-associated carbonic anhydrase in photosynthetic carbon assimilation in Chlamydomonas reinhardtii. (1/2359)

Intracellular carbonic anhydrases (CA) in aquatic photosynthetic organisms are involved in the CO2-concentrating mechanism (CCM), which helps to overcome CO2 limitation in the environment. In the green alga Chlamydomonas reinhardtii, this CCM is initiated and maintained by the pH gradient created across the chloroplast thylakoid membranes by photosystem (PS) II-mediated electron transport. We show here that photosynthesis is stimulated by a novel, intracellular alpha-CA bound to the chloroplast thylakoids. It is associated with PSII on the lumenal side of the thylakoid membranes. We demonstrate that PSII in association with this lumenal CA operates to provide an ample flux of CO2 for carboxylation.  (+info)

Two light-activated conductances in the eye of the green alga Volvox carteri. (2/2359)

Photoreceptor currents of the multicellular green alga Volvox carteri were analyzed using a dissolver mutant. The photocurrents are restricted to the eyespot region of somatic cells. Photocurrents are detectable from intact cells and excised eyes. The rhodopsin action spectrum suggests that the currents are induced by Volvox rhodopsin. Flash-induced photocurrents are a composition of a fast Ca2+-carried current (PF) and a slower current (PS), which is carried by H+. PF is a high-intensity response that appears with a delay of less than 50 micros after flash. The stimulus-response curve of its initial rise is fit by a single exponential and parallels the rhodopsin bleaching. These two observations suggest that the responsible channel is closely connected to the rhodopsin, both forming a tight complex. At low flash energies PS is dominating. The current delay increases up to 10 ms, and the PS amplitude saturates when only a few percent of the rhodopsin is bleached. The data are in favor of a second signaling system, which includes a signal transducer mediating between rhodopsin and the channel. We present a model of how different modes of signal transduction are accomplished in this alga under different light conditions.  (+info)

Multiple pathways for ultrafast transduction of light energy in the photosynthetic reaction center of Rhodobacter sphaeroides. (3/2359)

A pathway of electron transfer is described that operates in the wild-type reaction center (RC) of the photosynthetic bacterium Rhodobacter sphaeroides. The pathway does not involve the excited state of the special pair dimer of bacteriochlorophylls (P*), but instead is driven by the excited state of the monomeric bacteriochlorophyll (BA*) present in the active branch of pigments along which electron transfer occurs. Pump-probe experiments were performed at 77 K on membrane-bound RCs by using different excitation wavelengths, to investigate the formation of the charge separated state P+HA-. In experiments in which P or BA was selectively excited at 880 nm or 796 nm, respectively, the formation of P+HA- was associated with similar time constants of 1.5 ps and 1. 7 ps. However, the spectral changes associated with the two time constants are very different. Global analysis of the transient spectra shows that a mixture of P+BA- and P* is formed in parallel from BA* on a subpicosecond time scale. In contrast, excitation of the inactive branch monomeric bacteriochlorophyll (BB) and the high exciton component of P (P+) resulted in electron transfer only after relaxation to P*. The multiple pathways for primary electron transfer in the bacterial RC are discussed with regard to the mechanism of charge separation in the RC of photosystem II from higher plants.  (+info)

Lipophilicity determination of some potential photosystem II inhibitors on reversed-phase high-performance thin-layer chromatography. (4/2359)

The retention characteristics of 25 2-cyano-3-methylthio-3-substituted amine-acrylates are determined using reversed-phase thin-layer chromatography (RP-TLC) with methanol-water mixtures as eluents. The relationship between Rm values and partition coefficients (C log P) are established. The Rm values decrease linearly with increasing methanol concentration in the eluent. The Rm values extrapolated to zero organic modifier concentration (Rm0) in the eluent are highly related to C log P. The Rm0 value can be used to evaluate the lipophilicity of this kind of compound.  (+info)

A functional model for O-O bond formation by the O2-evolving complex in photosystem II. (5/2359)

The formation of molecular oxygen from water in photosynthesis is catalyzed by photosystem II at an active site containing four manganese ions that are arranged in di-mu-oxo dimanganese units (where mu is a bridging mode). The complex [H2O(terpy)Mn(O)2Mn(terpy)OH2](NO3)3 (terpy is 2,2':6', 2"-terpyridine), which was synthesized and structurally characterized, contains a di-mu-oxo manganese dimer and catalyzes the conversion of sodium hypochlorite to molecular oxygen. Oxygen-18 isotope labeling showed that water is the source of the oxygen atoms in the molecular oxygen evolved, and so this system is a functional model for photosynthetic water oxidation.  (+info)

Photosystem I, an improved model of the stromal subunits PsaC, PsaD, and PsaE. (6/2359)

An improved electron density map of photosystem I (PSI) calculated at 4-A resolution yields a more detailed structural model of the stromal subunits PsaC, PsaD, and PsaE than previously reported. The NMR structure of the subunit PsaE of PSI from Synechococcus sp. PCC7002 (Falzone, C. J., Kao, Y.-H., Zhao, J., Bryant, D. A., and Lecomte, J. T. J. (1994) Biochemistry 33, 6052-6062) has been used as a model to interpret the region of the electron density map corresponding to this subunit. The spatial orientation with respect to other subunits is described as well as the possible interactions between the stromal subunits. A first model of PsaD consisting of a four-stranded beta-sheet and an alpha-helix is suggested, indicating that this subunit partly shields PsaC from the stromal side. In addition to the improvements on the stromal subunits, the structural model of the membrane-integral region of PSI is also extended. The current electron density map allows the identification of the N and C termini of the subunits PsaA and PsaB. The 11-transmembrane alpha-helices of these subunits can now be assigned uniquely to the hydrophobic segments identified by hydrophobicity analyses.  (+info)

Localization of two phylloquinones, QK and QK', in an improved electron density map of photosystem I at 4-A resolution. (7/2359)

An improved electron density map of photosystem I from Synechococcus elongatus calculated at 4-A resolution for the first time reveals a second phylloquinone molecule and thereby completes the set of cofactors constituting the electron transfer system of this iron-sulfur type photosynthetic reaction center: six chlorophyll a, two phylloquinones, and three Fe4S4 clusters. The location of the newly identified phylloquinone pair, the individual plane orientations of these molecules, and the resulting distances to other cofactors of the electron transfer system are discussed and compared with those determined by magnetic resonance techniques.  (+info)

Structural features and assembly of the soluble overexpressed PsaD subunit of photosystem I. (8/2359)

PsaD is a peripheral protein on the reducing side of photosystem I (PS I). We expressed the psaD gene from the thermophilic cyanobacterium Mastigocladus laminosus in Escherichia coli and obtained a soluble protein with a polyhistidine tag at the carboxyl terminus. The soluble PsaD protein was purified by Ni-affinity chromatography and had a mass of 16716 Da by MALDI-TOF. The N-terminal amino acid sequence of the overexpressed PsaD matched the N-terminal sequence of the native PsaD from M. laminosus. The soluble PsaD could assemble into the PsaD-less PS I. As determined by isothermal titration calorimetry, PsaD bound to PS I with 1.0 binding site per PS I, the binding constant of 7.7x10(6) M-1, and the enthalpy change of -93.6 kJ mol-1. This is the first time that the binding constant and binding heat have been determined in the assembly of any photosynthetic membrane protein. To identify the surface-exposed domains, purified PS I complexes and overexpressed PsaD were treated with N-hydroxysuccinimidobiotin (NHS-biotin) and biotin-maleimide, and the biotinylated residues were mapped. The Cys66, Lys21, Arg118 and Arg119 residues were exposed on the surface of soluble PsaD whereas the Lys129 and Lys131 residues were not exposed on the surface. Consistent with the X-ray crystallographic studies on PS I, circular dichroism spectroscopy revealed that PsaD contains a small proportion of alpha-helical conformation.  (+info)

Carotenoid excited-state properties in photosynthetic purple bacterial reaction centers: Effects of the protein environment<...Carotenoid excited-state properties in photosynthetic purple bacterial reaction centers: Effects of the protein environment<...
TY - JOUR. T1 - Carotenoid excited-state properties in photosynthetic purple bacterial reaction centers. T2 - Effects of the protein environment. AU - Pan, Jie. AU - Lin, Su. AU - Allen, James. AU - Williams, Joann. AU - Frank, Harry A.. AU - Woodbury, Neal. PY - 2011/6/2. Y1 - 2011/6/2. N2 - Carotenoid excited-state properties are characterized and compared in reaction centers (RCs) of wild-type (WT) Rhodobacter (Rb.) sphaeroides, and a mutant VR(L157), in which the near-infrared absorbance band associated with the primary electron donor, P, is missing. Energy transfer from the carotenoid (spheroidenone) S2 and relaxed S1 excited states to an adjacent monomeric-bacteriochlorophyll is unchanged between WT and the mutant RC samples. However, two other excited states, including a vibrationally hot S1 state and a state referred to as S*, have distinct properties in the two RCs. The lifetime of the hot S1 state is significantly shortened in the P-less mutant compared to WT RCs (450 fs vs 800 fs, ...
Photosynthetic reaction centre protein family - WikipediaPhotosynthetic reaction centre protein family - Wikipedia
Photosynthetic reaction centre proteins are main protein components of photosynthetic reaction centres of bacteria and plants. The photosynthetic apparatus in non-oxygenic bacteria consists of light-harvesting protein-pigment complexes LH1 and LH2, which use carotenoid and bacteriochlorophyll as primary donors. LH1 acts as the energy collection hub, temporarily storing it before its transfer to the photosynthetic reaction centre (RC). Electrons are transferred from the primary donor via an intermediate acceptor (bacteriophaeophytin) to the primary acceptor (quinine Qa), and finally to the secondary acceptor (quinone Qb), resulting in the formation of ubiquinol QbH2. RC uses the excitation energy to shuffle electrons across the membrane, transferring them via ubiquinol to the cytochrome bc1 complex in order to establish a proton gradient across the membrane, which is used by ATP synthetase to form ATP. The core complex is anchored in the cell membrane, consisting of one unit of RC surrounded by ...
Antievolution.org - Antievolution.org Discussion Board -Topic::The Origins of PhotosynthesisAntievolution.org - Antievolution.org Discussion Board -Topic::The Origins of Photosynthesis
The evolutionary origin of photosynthetic reaction centers has long remained elusive. Here, we use sequence and structural analysis to demonstrate an evolutionary link between the cytochrome b subunit of the cytochrome bc(1) complex and the core polypeptides of the photosynthetic bacterial reaction center. In particular, we have identified an area of significant sequence similarity between a three contiguous membrane-spanning domain of cytochrome b, which contains binding sites for two hemes, and a three contiguous membrane-spanning domain in the photosynthetic reaction center core subunits, which contains binding sites for cofactors such as (bacterio)chlorophylls, (bacterio)pheophytin and a non-heme iron. Three of the four heme ligands in cytochrome b are found to be conserved with the cofactor ligands in the reaction center polypeptides. Since cytochrome b and reaction center polypeptides both bind tetrapyrroles and quinones for electron transfer, the observed sequence, functional and ...
Antievolution.org - Antievolution.org Discussion Board -Topic::The Origins of PhotosynthesisAntievolution.org - Antievolution.org Discussion Board -Topic::The Origins of Photosynthesis
The evolutionary origin of photosynthetic reaction centers has long remained elusive. Here, we use sequence and structural analysis to demonstrate an evolutionary link between the cytochrome b subunit of the cytochrome bc(1) complex and the core polypeptides of the photosynthetic bacterial reaction center. In particular, we have identified an area of significant sequence similarity between a three contiguous membrane-spanning domain of cytochrome b, which contains binding sites for two hemes, and a three contiguous membrane-spanning domain in the photosynthetic reaction center core subunits, which contains binding sites for cofactors such as (bacterio)chlorophylls, (bacterio)pheophytin and a non-heme iron. Three of the four heme ligands in cytochrome b are found to be conserved with the cofactor ligands in the reaction center polypeptides. Since cytochrome b and reaction center polypeptides both bind tetrapyrroles and quinones for electron transfer, the observed sequence, functional and ...
Light-induced charge separation in ruthenium based triads : New variations on an old themeLight-induced charge separation in ruthenium based triads : New variations on an old theme
Success with artificial photosynthesis requires control of the photoinduced electron transfer reactions leading to charge-separated states. In this review, some new ideas to optimize such charge-separated states in ruthenium(II) polypyridyl based three-component systems with respect to: (1) long lifetimes and (2) ability to store sufficient energy for catalytic water splitting, are presented. To form long-lived charge-separated states, a manganese complex as electron donor and potential catalyst for water oxidation has been used. The recombination reaction is unusually slow because it occurs deep down in the Marcus normal region as a consequence of the large bond reorganization following the manganese oxidation. For the creation of high energy charge-separated states, a strategy using bichromophoric systems is presented. By consecutive excitations of the two chromophores, the formation of charge-separated states that lie higher in energy than either of the two excited states could in theory be ...
Effect of anions on the binding and oxidation of divalent manganese and iron in modified bacterial reaction centers<...Effect of anions on the binding and oxidation of divalent manganese and iron in modified bacterial reaction centers<...
TY - JOUR. T1 - Effect of anions on the binding and oxidation of divalent manganese and iron in modified bacterial reaction centers. AU - Tang, Kai. AU - Williams, Jo Ann C.. AU - Allen, James P.. AU - Kálmán, László. PY - 2009/1/1. Y1 - 2009/1/1. N2 - The influence of different anions on the binding and oxidation of manganous and ferrous cations was studied in four mutants of bacterial reaction centers that can bind and oxidize these metal ions. Light-minus-dark difference optical and electron paramagnetic resonance spectroscopies were applied to monitor electron transfer from bound divalent metal ions to the photo-oxidized bacteriochlorophyll dimer in the presence of five different anions. At pH 7, bicarbonate was found to be the most effective for both manganese and iron binding, with dissociation constants around 1 μM in three of the mutants. The pH dependence of the dissociation constants for manganese revealed that only bicarbonate and acetate were able to facilitate the binding and ...
Sensors | Free Full-Text | Bio-nanocomposite Photoelectrode Composed of the BacteriaPhotosynthetic Reaction Center Entrapped on...Sensors | Free Full-Text | Bio-nanocomposite Photoelectrode Composed of the BacteriaPhotosynthetic Reaction Center Entrapped on...
A new kind of bio-nanocomposite photoelectrode was fabricated through directimmobilization of the bacterial photosynthetic reaction center (RC) proteins on ananocrystalline TiO2 matrix prepared by anodic electrodeposition. The near-infrared (NIR)-visible absorption and fluorescence emission spectra displayed that structure and activity ofthe RC remained unaltered on the nano-TiO2 film surface. High efficient light-harvesting ofthe NIR light energy by RC contributed to the distinct enhancement of the photoelectricconversion on such nanoporous matrix, which would provide a new strategy to developversatile biomimic energy convertors or photoelectric sensors.
Snapshots of a photosynthetic reaction centreSnapshots of a photosynthetic reaction centre
These experimental observations were interpreted as due to a change in the conformation of TyrL162, which moves approximately 1.3 Å towards the special pair (Figure 65: blue: conformation photo-activated state; grey: conformation resting state) in response to light. Molecular dynamics simulations and free energy calculations suggested that this motion arises because Tyr162 becomes deprotonated following the primary electron transfer event of an electron away from the special pair (P960). This supports the concept of complementary electron-proton transfer reactions, whereby the excess positive charge on P+960 induces a proton transfer away from TyrL162 in a direction opposite to that of the electron transfer. This principle may find application in the future design of energy transducing systems of artificial photosynthesis.. Principal publication and authors. A.B. Wöhri (a,b), G. Katona (c), L.C. Johansson (c), E. Fritz (c), E. Malmerberg (c), M. Andersson (a), J. Vincent (d), M. Eklund (d), M. ...
JCM 6170 Strain Passport - StrainInfoJCM 6170 Strain Passport - StrainInfo
Erythrobacter longus bchX, bchY, bchZ, ORFQ, pufB, pufA, pufL, pufM genes for chlorophillide reductase subunit, chlorophillide reductase subunit, chlorophillide reductase subunit, hypothetical protein, beta subunit of light-harvesting 1 complex, alpha subunit of light-harvesting 1 complex, L subunit of photosynthetic reaction center, M subunit of photosynthetic reaction center, partial and complete ...
Domain architectures: Photosynthetic reaction centre, L/M (IPR000484) | InterPro | EMBL-EBIDomain architectures: Photosynthetic reaction centre, L/M (IPR000484) | InterPro | EMBL-EBI
InterPro provides functional analysis of proteins by classifying them into families and predicting domains and important sites. We combine protein signatures from a number of member databases into a single searchable resource, capitalising on their individual strengths to produce a powerful integrated database and diagnostic tool.
Proteins matched: Photosynthetic reaction centre, L/M (IPR000484) | InterPro | EMBL-EBIProteins matched: Photosynthetic reaction centre, L/M (IPR000484) | InterPro | EMBL-EBI
InterPro provides functional analysis of proteins by classifying them into families and predicting domains and important sites. We combine protein signatures from a number of member databases into a single searchable resource, capitalising on their individual strengths to produce a powerful integrated database and diagnostic tool.
An artificial photosynthetic membrane<...An artificial photosynthetic membrane<...
TY - JOUR. T1 - An artificial photosynthetic membrane. AU - Gust, John Devens. AU - Moore, Thomas A. AU - Moore, Ana L. PY - 1999. Y1 - 1999. N2 - In bacteria, photosynthesis involves absorption of light by antenna systems and transfer of excitation to reaction centers, which convert the excitation energy to electrochemical potential energy in the form of transmembrane charge separation. A proton-pumping protein uses this stored energy to generate proton motive force across the membrane, which in turn drives the synthesis of adenosine triphosphate (ATP). All of these steps can now be mimicked in the laboratory. Artificial reaction centers can be prepared from porphyrins and other chromophores, electron donors, and electron acceptors linked by covalent bonds. Suitable artificial reaction centers can be vectorially inserted into the lipid bilayers of liposomes, where they function as constituents of transmembrane lightdriven proton pumps. Finally, the proton motive force produced can be used to ...
Publications • Prof. Dr. Klaus Möbius • Department of PhysicsPublications • Prof. Dr. Klaus Möbius • Department of Physics
Time-resolved X-, K-, and W-band EPR of the radical pair state P700+A1− of photosystem I in comparison with P865+QA− in bacterial reaction centers ...
RCSB PDB for 1K6LRCSB PDB for 1K6L
1K6L: The structure of a mutant photosynthetic reaction center shows unexpected changes in main chain orientations and quinone position.
RCSB PDB - Protein Feature View - Photosynthetic reaction center M subunit - A8ASG6 (A8ASG6 THETI)RCSB PDB - Protein Feature View - Photosynthetic reaction center M subunit - A8ASG6 (A8ASG6 THETI)
The PDB archive contains information about experimentally-determined structures of proteins, nucleic acids, and complex assemblies. As a member of the wwPDB, the RCSB PDB curates and annotates PDB data according to agreed upon standards. The RCSB PDB also provides a variety of tools and resources. Users can perform simple and advanced searches based on annotations relating to sequence, structure and function. These molecules are visualized, downloaded, and analyzed by users who range from students to specialized scientists.
Clones in pair P000117.Clones in pair P000117.
Explanatory notes: "*" The opposite end is in another contig. "**" The opposite end is in same contig. "#" The opposite end is singlet. "-" The opposite end has no seqence.. ...
Clones in pair P000044.Clones in pair P000044.
Explanatory notes: "*" The opposite end is in another contig. "**" The opposite end is in same contig. "#" The opposite end is singlet. "-" The opposite end has no seqence.. ...
strange reaction - Symptoms, Treatments and Resources for strange reactionstrange reaction - Symptoms, Treatments and Resources for strange reaction
strange reaction - MedHelps strange reaction Center for Information, Symptoms, Resources, Treatments and Tools for strange reaction. Find strange reaction information, treatments for strange reaction and strange reaction symptoms.
Institute of Cancer Research Repository - Biochemical and structural analyses of a higher plant photosystem II supercomplex of...Institute of Cancer Research Repository - Biochemical and structural analyses of a higher plant photosystem II supercomplex of...
Photosystem II of higher plants is a multisubunit transmembrane complex composed of a core moiety and an extensive peripheral antenna system. The number of antenna polypeptides per core complex is modulated following environmental conditions in order to optimize photosynthetic performance. In this study, we used a barley (Hordeum vulgare) mutant, viridis zb63, which lacks photosystem I, to mimic extreme and chronic overexcitation of photosystem II. The mutation was shown to reduce the photosystem II antenna to a minimal size of about 100 chlorophylls per photosystem II reaction centre, which was not further reducible. The minimal photosystem II unit was analysed by biochemical methods and by electron microscopy, and found to consist of a dimeric photosystem II reaction centre core surrounded by monomeric Lhcb4 (chlorophyll protein 29), Lhcb5 (chlorophyll protein 26) and trimeric light-harvesting complex II antenna proteins. This minimal photosystem II unit forms arrays in vivo, possibly to ...
Recognition signal for the C-terminal processing protease of D1 precursor protein in the photosystem II reaction center An...Recognition signal for the C-terminal processing protease of D1 precursor protein in the photosystem II reaction center An...
TY - JOUR. T1 - Recognition signal for the C-terminal processing protease of D1 precursor protein in the photosystem II reaction center An analysis using synthetic oligopeptides. AU - Taguchi, Fumiko. AU - Yamamoto, Yumiko. AU - Inagaki, Noritoshi. AU - Satoh, Kimiyuki. PY - 1993/7. Y1 - 1993/7. N2 - Synthetic oligopeptides of different chain lengths of 11 to 38 amino acids, corresponding to the carboxyl-terminal sequence of D1 precursor protein of the photosystem II reaction center, were subjected to a proteolytic cleavage by a processing enzyme isolated from spinach, in order to analyze the recognition signal. Practically the same Km and Vmax values were obtained for the oligopeptides consisting of more than 19 amino acids; a decrease in affinity, without affecting the Vmax value, was observed for the peptide consisting of 16 amino acids; no detectable activity was found for the peptide with 11 amino acids. When Asp-342 (12th residue from C-terminus) was replaced with Asn, for the peptide ...
Photosystem I reaction center elisa and antibodyPhotosystem I reaction center elisa and antibody
Shop Photosystem I reaction center ELISA Kit, Recombinant Protein and Photosystem I reaction center Antibody at MyBioSource. Custom ELISA Kit, Recombinant Protein and Antibody are available.
Bound manganese oxides capable of reducing the bacteriochlorophyll dimer of modified reaction centers from Rhodobacter...Bound manganese oxides capable of reducing the bacteriochlorophyll dimer of modified reaction centers from Rhodobacter...
TY - JOUR. T1 - Bound manganese oxides capable of reducing the bacteriochlorophyll dimer of modified reaction centers from Rhodobacter sphaeroides. AU - Espiritu, Eduardo. AU - Chamberlain, Kori D.. AU - Williams, Jo Ann C.. AU - Allen, James P.. PY - 2019/1/1. Y1 - 2019/1/1. N2 - A biohybrid model system is described that interfaces synthetic Mn-oxides with bacterial reaction centers to gain knowledge concerning redox reactions by metal clusters in proteins, in particular the Mn4CaO5 cluster of photosystem II. The ability of Mn-oxides to bind to modified bacterial reaction centers and transfer an electron to the light-induced oxidized bacteriochlorophyll dimer, P+, was characterized using optical spectroscopy. The environment of P was altered to obtain a high P/P+ midpoint potential. In addition, different metal-binding sites were introduced by substitution of amino acid residues as well as extension of the C-terminus of the M subunit with the C-terminal region of the D1 subunit of photosystem ...
Photosystem II CP43 reaction center protein elisa and antibodyPhotosystem II CP43 reaction center protein elisa and antibody
Shop Photosystem II CP43 reaction center protein ELISA Kit, Recombinant Protein and Photosystem II CP43 reaction center protein Antibody at MyBioSource. Custom ELISA Kit, Recombinant Protein and Antibody are available.
Photosynthetic reaction centre/carbon nanotube bundle compositesPhotosynthetic reaction centre/carbon nanotube bundle composites
Since their discovery, carbon nanotubes (CNTs) have attracted intense attention to broad range of potential applications. In contrast to the 1D isolated single-walled carbon nanotubes (SWCNT), 2D films or bundles made of thousands of tubes have been introduced as more advantageous building blocks for new types of applications in mechanically flexible and stretchable, optically transparent electronic systems. In our experiments, we combined photosynthetic reaction centre proteins, the light energy converter units in living cells, purified from purple bacteria, with multiwalled carbon nanotube (MWCNT) bundles. The change in the conductivity of the bare MWCNT bundles and the RC/MWCNT composite after light excitation was measured and compared. We found that the electrical conductivity under light excitation depends on the intrinsic conductivity of individual tubes within the bundles and on structural characteristics, like geometry (diameter, length, spatial arrangement, interconnects, etc.) and the ...
Download Molecular Excitation Dynamics And RelaxationDownload Molecular Excitation Dynamics And Relaxation
Home download molecular excitation dynamics and in mind items. download molecular excitation, sonic), 199-217. New York: Random House Inc. The download molecular excitation dynamics signing: containing weight. American Educational Research Journal, 28, 849-874. Educational Psychology Handbook: Vol. Theories, Constructs, and particular fields. American Psychological Association, Washington, DC. You should configure the download molecular excitation of features 18 and older at your question. The humans download molecular excitation relationship for Psi Beta rights will understand until February 28, 2016. are your sandboxes have this download to assist on to the Psi Beta criticism quality and see their groups. The single download molecular upon is up determine giant Supplement general as cases and history politics. After March 5, 2016 the download schools will surprise fashioned likely to being Psi Beta leaders. amateur pages consume owned to like their lively levels download. apply your ...
DIGITAL.CSIC: Precise location of the Cu(II)-inhibitory binding site in higher plant and bacterial photosynthetic reaction...DIGITAL.CSIC: Precise location of the Cu(II)-inhibitory binding site in higher plant and bacterial photosynthetic reaction...
Light-dependent absorption change at 325 nm, ascribed to Q(A) activity, was strongly reduced in the presence of Cu(II) in oxygen-evolving core complex. This change was much less affected in the presence of the herbicide 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), indicating that the Cu(II)- binding site is different from that of the DCMU and that Cu(II) blocks Q(A) reduction. Cu(II) did not eliminate the absorption change at 545 nm, ascribed to pheophytin reduction, in Na2S2O4-treated oxygen-evolving core and D1- D2-cytochrome b559 complexes. This indicates that Cu(II) does not affect the electron transport between P680 and pheophytin. Moreover, the activity of the bacterial reaction center probed by the absorption change at 790 nm was inhibited by Cu(II), but the signal at 530 nm, associated to the reduction of bacteriopheophytin in Na2S2O4-treated reaction center, was not inhibited. We conclude that Cu(II) impaired the photosynthetic electron transport between pheophytin and Q(A) in both ...
Stabilising the lowest energy charge-separated state in a {metal chromophore - fullerene} assembly: a tuneable panchromatic...Stabilising the lowest energy charge-separated state in a {metal chromophore - fullerene} assembly: a tuneable panchromatic...
Creating artificial photosynthetic devices that can mimic natural light-driven processes is one of the major challenges for sustainable energy production.1 The chemical compounds utilised as the main components in such devices typically contain three major building blocks: a chromophore which is responsible for the efficient visible light energy harvesting, and donor and acceptor moieties which are responsible for the formation of long-lived charge separated radical-ion pairs upon photoexcitation.2 Fullerenes possess excellent electron accepting capacity3 and have low reorganisation energies4 encouraging electron-transfer processes. They have therefore been extensively utilised as a component in artificial photosynthetic systems.5 Combining C60 fullerene with a suitable electron donor results in the formation of donor-acceptor (D-A) dyads potentially capable of generating the long-lived charge-separated states, the key intermediate in operation of photovoltaic devices, organic electronics and ...
Difference between revisions of Paul Jaschke - OpenWetWareDifference between revisions of "Paul Jaschke" - OpenWetWare
Jaschke PR, Drake I, Beatty JT. (2009). Modification of a French pressure cell to improve microbial cell disruption. Photosynth Res. 102(1): 95-7. Abstract PDF Jaschke PR. (2010). Discovery and characterization of a new zinc-bacteriochlorophyll biosynthetic pathway and photosystem in a magnesium-chelatase mutant. PhD Thesis. University of British Columbia. Abstract PDF Lin S,Jaschke PR, Wang H, Paddock M, Tufts A, Allen JP, Rosell FI, Mauk GA, Woodbury NW, Beatty JT. (2009). Electron transfer in the Rhodobacter sphaeroides reaction center assembled with zinc bacteriochlorophyll. Proceedings of the National Academy of Sciences of the USA.106(21): 8537-42. Abstract PDF Jaschke PR, LeBlanc HN, Lang AS, Beatty JT. (2008). The PucC protein of Rhodobacter capsulatus mitigates an inhibitory effect of light-harvesting 2 alpha and beta proteins on light-harvesting complex 1. Photosynthesis Research. 95(2-3): 279-84. Abstract PDF Jaschke PR, Beatty JT. (2007). The photosystem of Rhodobacter sphaeroides ...
Difference between revisions of Paul Jaschke - OpenWetWareDifference between revisions of "Paul Jaschke" - OpenWetWare
Jaschke PR, Drake I, Beatty JT. (2009). Modification of a French pressure cell to improve microbial cell disruption. Photosynth Res. 102(1): 95-7. Abstract PDF Jaschke PR. (2010). Discovery and characterization of a new zinc-bacteriochlorophyll biosynthetic pathway and photosystem in a magnesium-chelatase mutant. PhD Thesis. University of British Columbia. Abstract PDF Lin S,Jaschke PR, Wang H, Paddock M, Tufts A, Allen JP, Rosell FI, Mauk GA, Woodbury NW, Beatty JT. (2009). Electron transfer in the Rhodobacter sphaeroides reaction center assembled with zinc bacteriochlorophyll. Proceedings of the National Academy of Sciences of the USA.106(21): 8537-42. Abstract PDF Jaschke PR, LeBlanc HN, Lang AS, Beatty JT. (2008). The PucC protein of Rhodobacter capsulatus mitigates an inhibitory effect of light-harvesting 2 alpha and beta proteins on light-harvesting complex 1. Photosynthesis Research. 95(2-3): 279-84. Abstract PDF Jaschke PR, Beatty JT. (2007). The photosystem of Rhodobacter sphaeroides ...
Insights into the Cyanobacterial Deg/HtrA ProteasesInsights into the Cyanobacterial Deg/HtrA Proteases
Proteins are the main machinery for all living processes in a cell; they provide structural elements, regulate biochemical reactions as enzymes, and are the interface to the outside as receptors and transporters. Like any other machinery proteins have to be assembled correctly and need maintenance after damage, e.g., caused by changes in environmental conditions, genetic mutations, and limitations in the availability of cofactors. Proteases and chaperones help in repair, assembly, and folding of damaged and misfolded protein complexes cost-effective, with low energy investment compared with neo-synthesis. Despite their importance for viability, the specific biological role of most proteases in vivo is largely unknown. Deg/HtrA proteases, a family of serinetype ATP-independent proteases, have been shown in higher plants to be involved in the degradation of the Photosystem II reaction center protein D1. The objective of this review is to highlight the structure and function of their cyanobacterial ...
S-LHCII - strongly bound trimeric light-harvesting complex II | AcronymAtticS-LHCII - strongly bound trimeric light-harvesting complex II | AcronymAttic
How is strongly bound trimeric light-harvesting complex II abbreviated? S-LHCII stands for strongly bound trimeric light-harvesting complex II. S-LHCII is defined as strongly bound trimeric light-harvesting complex II rarely.
psbD - Photosystem II D2 protein - Synechococcus phage syn9 - psbD gene & proteinpsbD - Photosystem II D2 protein - Synechococcus phage syn9 - psbD gene & protein
Photosystem II (PSII) is a light-driven water: plastoquinone oxidoreductase that uses light energy to abstract electrons from H(2)O, generating O(2) and a proton gradient subsequently used for ATP formation. It consists of a core antenna complex that captures photons, and an electron transfer chain that converts photonic excitation into a charge separation. The D1/D2 (PsbA/PsbA) reaction center heterodimer binds P680, the primary electron donor of PSII as well as several subsequent electron acceptors. D2 is needed for assembly of a stable PSII complex.
Photosystem II molecule - Stock Image F006/9500 - Science Photo LibraryPhotosystem II molecule - Stock Image F006/9500 - Science Photo Library
Photosystem II. Molecular model of the photosystem II complex. Photosystems are protein complexes involved in photosynthesis. Photosystem II is found on the thylakoid membranes of cyanobacteria, algae and plants. It is the first step in photosynthesis. It absorbs light and uses the energy to drive the oxidation of water, creating oxygen as a byproduct, and the reduction of plastoquinone. - Stock Image F006/9500
Light-harvesting complexLight-harvesting complex
A light harvesting complex is one or more polypeptide chains containing photosynthetic pigments, which surrounds a photosynthetic reaction centre and focuses energy, attained from photons absorbed by the pigment, inward toward the reaction centre
2wsf - Proteopedia, life in 3D2wsf - Proteopedia, life in 3D
PSAC_PEA] Apoprotein for the two 4Fe-4S centers FA and FB of photosystem I (PSI); essential for photochemical activity. FB is the terminal electron acceptor of PSI, donating electrons to ferredoxin. The C-terminus interacts with PsaA/B/D and helps assemble the protein into the PSI complex. Required for binding of PsaD and PsaE to PSI. PSI is a plastocyanin-ferredoxin oxidoreductase, converting photonic excitation into a charge separation, which transfers an electron from the donor P700 chlorophyll pair to the spectroscopically characterized acceptors A0, A1, FX, FA and FB in turn (By similarity).[HAMAP-Rule:MF_01303] [CAB6_ARATH] The light-harvesting complex (LHC) functions as a light receptor, it captures and delivers excitation energy to photosystems with which it is closely associated. [PSAI_PEA] May help in the organization of the PsaL subunit. [PSAB_PEA] PsaA and PsaB bind P700, the primary electron donor of photosystem I (PSI), as well as the electron acceptors A0, A1 and FX. PSI is a ...
Aro, Eva Mari - Academy of FinlandAro, Eva Mari - Academy of Finland
University of Turku Eva-Mari Aro works in the Department of Biology, University of Turku. She is a professor in Plant Physiology and Molecular biology.. Aros research interest is focused on light reactions of photosynthesis, particularly Photosystem II (PSII) that functions in water splitting reactions in the thylakoid membrane and evolves oxygen to the atmosphere. Besides this basic function of PSII, it also participates in signalling cascades leading to acclimation of plants to changed environmental conditions. Although light is an absolute requirements for the function of photosynthesis, light also damages the components of PSII.. The group of Dr Aro has had an important role in solving the mechanisms of inactivation and damage of PSII in light, in studies of degradation and de novo synthesis of the reaction centre protein D1, and in solving the repair mechanisms and re-assembly of PSII consisting up to 28 different proteins and various co-factors. The group has also studied the ...
PDB 1f6nPDB 1f6n
X-ray structure analyses of photosynthetic reaction center variants from Rhodobacter sphaeroides: structural changes induced by point mutations at position L209 modulate electron and proton transfer ...
Pliable proteins keep photosynthesis on the light pathPliable proteins keep photosynthesis on the light path
Amazingly, the reaction center still works with essentially the same physical chemical properties as the normal system," said Neal Woodbury, deputy director of the Biodesign Institute. "This was a real puzzle when Su first did these measurements, but she was able to figure out why." "The electron transfer driving force can be determined by either the properties of the metal cofactors themselves or through their interaction with the protein," said Lin. "In the case of the zinc reaction center, the driving force is regulated through the coordination of the metal." "Once again, biology shows its resilience so that changes in one area are compensated by changes in others and the proteins ability to dynamically adjust," said Woodbury.. The results may enable researchers to explore a deeper understanding of the structure, function, and evolution of photosynthesis reaction centers in photosystems I and II. Of particular interest, are studies that focus on the interaction between chlorophylls and ...
Photosystems - General Biology DiscussionPhotosystems - General Biology Discussion
The electron from PSI goes to higher state...passes down the chain all the way to PSII (which replaces the electron deficient when light excites electrons in PSII reaction centre to a higher state)...so the NADPH that is produced ultimately comes from the electrons from PSII..I feel this is correct (but who knows ...
KAKEN - Research Projects | Turn over regulation of photosystem II proteins by the light-dependent transcription in...KAKEN - Research Projects | Turn over regulation of photosystem II proteins by the light-dependent transcription in...
Principal Investigator：SHIINA Takashi, Project Period (FY)：1996 - 1997, Research Category：Grant-in-Aid for Scientific Research (C), Section：一般, Research Field：光生物学
A New Map of Wonders: All possible paths simultaneouslyA New Map of Wonders: All possible paths simultaneously
Efficiently converting light into electricity requires preserving the energy of an exciton [an electron-ion pair] as it travels deep within reaction centre of the leaf [and] the key to [this] lies in way it travels to the reaction centre. Researchers discovered to their great surprise in 2007 that plants use a [trick] from the realm of quantum physics to help excitons find their way. Rather than bumping randomly through a forest of chlorophyll molecules until they happen to reach their destination...each exciton spreads out over all possible paths simultaneously, and then funnels down through the most efficient route ...
Factors affecting the rate of photosynthesis experiment. Investigating the factors, which affect the rate of photosynthesis in...Factors affecting the rate of photosynthesis experiment. Investigating the factors, which affect the rate of photosynthesis in...
Factors affecting the rate of photosynthesis experiment.It is besides possible that the photosynthetic reactions in the works are happening at their maximal possible rate and so can non be increased any more.
Medifill™ II ParticlesMedifill™ II Particles
Important Notice: The contents of the website such as text, graphics, images, and other materials contained on the website ("Content") are for informational purposes only. The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. The content is not intended to substitute manufacturer instructions. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or product usage. Refer to the Legal Notice for express terms of use.. ...
Damaged Amino acids IDed in Study [image] | EurekAlert! Science NewsDamaged Amino acids ID'ed in Study [image] | EurekAlert! Science News
The three-colored formations (red, purple, yellow) are the three groups of damaged amino acids in Photosystem II identified in this study. They are centered on the active site (Mn cluster, shown in green), and trace three pathways connecting the Mn cluster to the surface of the complex, the watery bulk medium of the cell.
Synthesis and reactions with CO and C2H4 of cobalt(I) complexes containing trimethylphosphine and chelating o...Synthesis and reactions with CO and C2H4 of cobalt(I) complexes containing trimethylphosphine and chelating o...
Synthesis and reactions with CO and C2H4 of cobalt(I) complexes containing trimethylphosphine and chelating o-diphenylphosphanylphenolate ligands ...
Iron-sulfur centers in the photosynthetic reaction center complex from Chlorobium vibrioforme. Differences from and...Iron-sulfur centers in the photosynthetic reaction center complex from Chlorobium vibrioforme. Differences from and...
TY - JOUR. T1 - Iron-sulfur centers in the photosynthetic reaction center complex from Chlorobium vibrioforme. Differences from and similarities to the iron-sulfur centers in Photosystem I. AU - Kjær, Bodil. AU - Jung, Yean Sung. AU - Yu, Lian. AU - Golbeck, John H.. AU - Scheller, Henrik Vibe. PY - 1994/7/1. Y1 - 1994/7/1. N2 - The photosynthetic reaction center complex from the green sulfur bacterium Chlorobium vibrioforme has been isolated under anaerobic conditions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis reveals polypeptides with apparent molecular masses of 80, 40, 30, 18, 15, and 9 kDa. The 80- and 18-kDa polypeptides are identified as the reaction center polypeptide and the secondary donor cytochrome c551 encoded by the pscA and pscC genes, respectively. N-terminal amino acid sequences identify the 40-kDa polypeptide as the bacteriochlorophyll a-protein of the baseplate (the Fenna-Matthews-Olson protein) and the 30-kDa polypeptide as the putative 2[4Fe-4S] protein ...
Excitation dynamics in phycoerythrin 545: Modeling of steady-state spectra and transient absorption with modified redfield...Excitation dynamics in phycoerythrin 545: Modeling of steady-state spectra and transient absorption with modified redfield...
TY - JOUR. T1 - Excitation dynamics in phycoerythrin 545. T2 - Modeling of steady-state spectra and transient absorption with modified redfield theory. AU - Novoderezhkin, Vladimir I.. AU - Doust, Alexander B.. AU - Curutchet, Carles. AU - Scholes, Gregory D.. AU - Van Grondelle, Rienk. PY - 2010/7/21. Y1 - 2010/7/21. N2 - We model the spectra and excitation dynamics in the phycobiliprotein antenna complex PE545 isolated from the unicellular photosynthetic cryptophyte algae Rhodomonas CS24. The excitonic couplings between the eight bilins are calculated using the CIS/6-31G method. The site energies are extracted from a simultaneous fit of the absorption, circular dichroism, fluorescence, and excitation anisotropy spectra together with the transient absorption kinetics using the modified Redfield approach. Quantitative fit of the data enables us to assign the eight exciton components of the spectra and build up the energy transfer picture including pathways and timescales of energy relaxation, ...
Plus itPlus it
The psbA gene codes for the D1 polypeptide of the photosystem II reaction center complex and is found in all photosynthetic organisms that carry out oxygenic photosynthesis. Here we describe the construction and characterization of a strain of the cyanobacterium Synechocystis sp PCC 6803 in which the three endogenous psbA genes are replaced by a single psbA gene from the chloroplast genome of the higher plant Poa annua. The resulting chimeric strain, KWPAS, grows photoautotrophically with a doubling time of 26 hours compared with 20 hours for wild-type Synechocystis 6803. The mutant oxidizes water to oxygen at light-saturated rates comparable with wild type, despite differences in 15% of the primary structure of D1 between these species. RNA gel blot analysis indicates the presence in KWPAS of a psbA transcript of approximately 1.25 kilobases, consistent with the chloroplast promoter also acting as a promoter in Synechocystis. By using antibodies specific for the carboxyl-terminal extension of ...
Possible role for molecular chaperones in assembly and repair of photosystem II | Biochemical Society TransactionsPossible role for molecular chaperones in assembly and repair of photosystem II | Biochemical Society Transactions
Genes of the HSP70 chaperone family are induced by light. In Chlamydomonas reinhardtii, the induction of HSP70 (70 kDa heat shock protein) chaperones by light results in a partial protection of photosystem II against damage by photoinhibitory conditions. Underexpression of a chloroplast-localized HSP70 protein caused an increased sensitivity of photosystem II to light. Overexpression of this protein had a protective effect. Fluorescence measurements and studies of the turnover of photosystem II core components suggest that this HSP70 might function in both the protection and the regeneration of photosystem II. This concept is supported by fractionation studies in which the plastid HSP70 was found associated with chloroplast membranes. Because the light-induced elevation of HSP70 levels provides protection for photosystem II, we examined whether the chloroplast is involved in this regulation and found that mutants defective in plastid-localized chlorophyll synthesis, i.e. the insertion of Mg2+ ...
Defining the Far-red Limit of Photosystem I THE PRIMARY CHARGE SEPARATION IS FUNCTIONAL TO 840 nmDefining the Far-red Limit of Photosystem I THE PRIMARY CHARGE SEPARATION IS FUNCTIONAL TO 840 nm
The photosynthetic process has the unique ability to capture energy from sunlight and accumulate that energy in sugars and starch. This thesis deals with the light driven part of photosynthesis. The aim has been to investigate how the light-absorbing protein complexes Photosystem I (PS I) and Photosystem II (PS II), react upon illumination of light with lower energy (far-red light; 700-850 nm) than the absorption peak at respective primary donor, P700 and P680. The results were unexpected. At 295 K, we showed that both PS I and PS II were able to perform photochemistry with light up to 130 nm above its respective primary donor absorption maxima. As such, it was found that the primary donors action spectra extended approximately 80 nm further out into the red-region of the spectrum than previously reported. The ability to perform photochemistry with far-red light was conserved at cryogenic temperatures (, 77 K) in both photosystems. By performing EPR measurements on various photosystem ...
Excitation energy transfer between monomolecular layers of light harvesting LH2 and LH1-reaction centre complexes printed on a...Excitation energy transfer between monomolecular layers of light harvesting LH2 and LH1-reaction centre complexes printed on a...
Previous work using reconstituted membranes has shown that energy transfer can be observed in mixed assemblies of LH2 and RCLH1 complexes,36-38 but controlling the relative stoichiometries and two-dimensional organization of energy donor/acceptor photosynthetic complexes on a nanometer scale, and the locations where excitation energy can migrate between them, presents new challenges. For some time, it has been possible to construct nanoarrays of single types of photosynthetic complex, starting with the light-harvesting LH2 complex of Rba. sphaeroides,18,19,21 and later the RCLH1 complex20 and the LHCII complex of plants.22 In each case the function of the complex, in terms of fluorescence emission, was retained; for LHCII it was possible to directly image the ability of immobilized molecules of LHCII to switch between fluorescent and quenched states. For LH2, there were indications of long-range excitation energy transfer; 80 nm-wide nanolines of LH2 complexes exhibited energy propagation on ...
SWISS-MODEL Repository | A0ZZ32SWISS-MODEL Repository | A0ZZ32
SWISS-MODEL Repository entry for A0ZZ32 (PSBZ_GOSBA), Photosystem II reaction center protein Z. Gossypium barbadense (Sea-island cotton) (Egyptian cotton)
Chlorophyll - New World EncyclopediaChlorophyll - New World Encyclopedia
The photosystem reaction centers consist of a "special pair" of chlorophyll a molecules that are characterized by their specific absorption maximum. The special pair in photosystem I are designated P700, and those from photosystem II are designated P680. The P is short for pigment, and the number is the specific absorption peak in nanometers for the chlorophyll molecules in each reaction center.. Chlorophyll a is common to all eukaryotic photosynthetic organisms, and, due to its central role in the reaction center, is essential for photosynthesis. The accessory pigments such as chlorophyll b and carotenoids are not essential. Some algae, such as brown algae and diatoms, use chlorophyll c as a substitute for chlorophyll b. Historically, red algae have been assumed to have chlorophyll d, although it could not be isolated from all species and even different collections of the same species. This puzzle has recently been resolved, since the chlorophyll d is actually from an epiphytic cyanobacterium ...
Durability of oxygen evolution of photosystem II incorporated into lipid bilayers<...Durability of oxygen evolution of photosystem II incorporated into lipid bilayers<...
TY - JOUR. T1 - Durability of oxygen evolution of photosystem II incorporated into lipid bilayers. AU - Noji, Tomoyasu. AU - Kondo, Masaharu. AU - Kawakami, Keisuke. AU - Shen, Jian Ren. AU - Nango, Mamoru. AU - Dewa, Takehisa. PY - 2014/11. Y1 - 2014/11. N2 - Photosystem II (PSII) has attracted a lot of attention for use in the construction of artificial photosynthetic materials due to its high activity of oxidation of water molecules. However, the robustness of PSII needs to be improved for in vitro application. In this study, we incorporated PSII (Thermosynechococcus vulcanus) into various phospholipid membranes to examine the activity and durability of oxygen evolution. PSII was incorporated into anionic 1,2-dioleoyl-sn-glycero-3-phospho-(1-rac-glycerol) (PSII-DOPG), zwitterionic 1,2-dioleoyl-sn-glycero-3-phosphocholine (PSII-DOPC), and cationic 1,2-dioleoyl-sn-glycero-3-ethylphosphocholine (PSII-EDOPC). Structural integrity of PSII was examined by absorption and fluorescence spectroscopy. ...
中国科学院南海海洋研究所机构知识库(SCSIO OpenIR): Arctic Micromonas uses protein pools and non-photochemical quenching to cope with temperature...中国科学院南海海洋研究所机构知识库(SCSIO OpenIR): Arctic Micromonas uses protein pools and non-photochemical quenching to cope with temperature...
Micromonas strains of small prasinophyte green algae are found throughout the worlds oceans, exploiting widely different niches. We grew arctic and temperate strains of Micromonas and compared their susceptibilities to photoinactivation of Photosystem II, their counteracting Photosystem II repair capacities, their Photosystem II content, and their induction and relaxation of non-photochemical quenching. In the arctic strain Micromonas NCMA 2099, the cellular content of active Photosystem II represents only about 50 % of total Photosystem II protein, as a slow rate constant for clearance of PsbA protein limits instantaneous repair. In contrast, the temperate strain NCMA 1646 shows a faster clearance of PsbA protein which allows it to maintain active Photosystem II content equivalent to total Photosystem II protein. Under growth at 2 A degrees C, the arctic Micromonas maintains a constitutive induction of xanthophyll deepoxidation, shown by second-derivative whole-cell spectra, which supports ...
Professor Min Chen - The University of SydneyProfessor Min Chen - The University of Sydney
Subject: Photosynthesis and function of pigment-protein complexes. 1. Chlorophyll f-photosynthesis. The photosynthetic reactions take place within the membrane-bound pigment-protein complexes, light harvesting systems and reaction centre systems. Chlorophylls are the essential pigments for photosynthesis. The function of chlorophyll fin photosynthetic reactions is uncertain. The approaches for this proposed project will include - methods for isolation of photosynthetic membranes and pigment-protein complexes by centrifugation, spectroscopic methods for probing the energy transfer pathways and liquid chromatographic methods for determining pigment compositions.. 2. Biosynthesis of chlorophyll f. The studies on photophysiological and biochemical properties of red-shifted chlorophylls will advance our understanding of their ecological and evolutionary significance. The recently discovered chlorophyll f has the most red-shifted absorption maximum that is involved in oxygenic photosynthesis. Its ...
Photosystem I, molecular model - Stock Image C001/3320 - Science Photo LibraryPhotosystem I, molecular model - Stock Image C001/3320 - Science Photo Library
Photosystem I. Computer model of the molecular structure of the Photosystem I complex, showing beta-carotene (orange), alpha-chlorophyll (green) and reaction centre subunits. Photosystems are protein complexes involved in photosynthesis. They are enzymes, typically found in the chloroplasts of plants, which absorb light and use it to reduce (add electrons to) other molecules. Photosystems I and II work together to form a photosynthetic chain that removes electrons from water, creating oxygen as a byproduct. - Stock Image C001/3320
Home - Dr Tanai CardonaHome - Dr Tanai Cardona
My research program employs a multidisciplinary approach to investigate the molecular evolution of photosynthetic reaction centers and photochemical energy conversion. My specialty is the evolution of Photosystem II, the water oxidizing enzyme of oxygenic photosynthesis. I want to figure out how water oxidation catalysis originated and what it implies for the evolution of oxygenic photosynthesis, early life, and the evolution of bioenergetic systems.. I write a science blog where I share some unpublished data and ideas about my research and some scientific commentary. If youre curious, please visit: http://tanaiscience.blogspot.co.uk/. I also post research updates on ResearchGate about the evolution of anoxygenic and oxygenic photosynthesis.. A bit more about me: I obtained a Biology degree at University of Los Andes in Colombia, followed by a doctorate in chemistry at Uppsala University in Sweden. I became interested in photosynthesis research when I was still a teenager and I consider myself ...
High light stimulates Deg1-dependent cleavage of the minor LHCII antenna proteins CP26 and CP29 and the PsbS protein in...High light stimulates Deg1-dependent cleavage of the minor LHCII antenna proteins CP26 and CP29 and the PsbS protein in...
The chloroplast Deg1 protein performs proteolytic cleavage of the photodamaged D1 protein of the photosystem II (PSII) reaction center, PSII extrinsic subunit PsbO and the soluble electron carrier plastocyanin. Using biochemical, immunological and mass spectrometry approaches we showed that the hete …
Identification of the Proton Pathway in Bacterial Reaction Centers: Decrease of Proton Transfer Rate by Mutation of Surface...Identification of the Proton Pathway in Bacterial Reaction Centers: Decrease of Proton Transfer Rate by Mutation of Surface...
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Roles of PsbI and PsbM in photosystem II dimer formation and stability studied by deletion mutagenesis and X-ray...Roles of PsbI and PsbM in photosystem II dimer formation and stability studied by deletion mutagenesis and X-ray...
PsbM and PsbI are two low molecular weight subunits of photosystem II (PSII), with PsbM being located in the center, and PsbI in the periphery, of the PSII dimer. In order to study the functions of these two subunits from a structural point of view, we crystallized and analyzed the crystal structure of PSII dimers from two mutants lacking either PsbM or PsbI. Our results confirmed the location of these two subunits in the current crystal structure, as well as their absence in the respective mutants. The relative contents of PSII dimers were found to be decreased in both mutants, with a concomitant increase in the amount of PSII monomers, suggesting a destabilization of PSII dimers in both of the mutants. On the other hand, the accumulation level of the overall PSII complexes in the two mutants was similar to that in the wild-type strain. Treatment of purified PSII dimers with lauryldimethylamine N-oxide at an elevated temperature preferentially disintegrated the dimers from the PsbM deletion ...
Photosynthesis - Essay about Photosynthesis, Chlorophyll aPhotosynthesis - Essay about Photosynthesis, Chlorophyll a
This 728 word essay is about Photosynthesis, Chlorophyll a, Chlorophyll, Photosynthetic reaction centre, Chloroplast, Biological pigment. Read the full essay now!
DiVA - Search resultDiVA - Search result
The cyanobacterium Synechococcus sp. PCC 7942 possesses a small psbA multigene family that codes for two distinct forms of the photosystem II reaction-center protein D1 (D1:1 and D1:2). We showed previously that the normally predominant D1 form (D1:1) was rapidly replaced with the alternative D1:2 when cells adapted to a photon irradiance of 50 mumol/m-2.s-1 are shifted to 500 mumol.m-2.s-1 and that this interchange was readily reversible once cells were allowed to recover under the original growth conditions. By using the psbA inactivation mutants R2S2C3 and R2K1 (which synthesize only D1:1 and D1:2, respectively), we showed that this interchange between D1 forms was essential for limiting the degree of photoinhibition as well as enabling a rapid recovery of photosynthesis. In this report, we have extended these findings by examining whether any intrinsic functional differences exist between the two D1 forms that may afford increased resistance to photoinhibition. Initial studies on the rate of ...
Rhodobacter sphaeroides (van Niel) Imhoff et al. ATCC ® 17029D-5&tRhodobacter sphaeroides (van Niel) Imhoff et al. ATCC ® 17029D-5&t
Rhodobacter sphaeroides ATCC ® 17029D-5™ Designation: Genomic DNA from Rhodobacter sphaeroides strain ATH 2.4.9 TypeStrain=False Application: Biotechnology
Quantum field theory approach to quantum transport in macromolecules | ECT*Quantum field theory approach to quantum transport in macromolecules | ECT*
In this talk, we present our recent development of a rigorous framework which is based on the Feynman-Venron path integral formalism for open quantum systems. By resorting on quantum fields to describe the quantum excitation dynamics and taking the classical limit for the molecular degrees of freedom, we are able to analytically perform the path integral over the heat-bath and olecular vibrations. As a result, the matrix elements of the density matrix are described by an effective field theory for the quantum degrees of freedom only, and can be computed in perturbation theory, using appropriate Feynman rules. Extension to non-perturbative approximative approaches is alsodiscussed. As an illustrative example, we will apply this approach to study quantum transport and de-coherence in a simple model for an organic conjugate polymer.. ...
Photosystem I | ProtocolPhotosystem I | Protocol
JoVE publishes peer-reviewed scientific video protocols to accelerate biological, medical, chemical and physical research. Watch our scientific video articles.
Phase I reaction | physiology | BritannicaPhase I reaction | physiology | Britannica
Other articles where Phase I reaction is discussed: poison: Biotransformation: In phase I, an exogenous molecule is modified by the addition of a functional group such as a hydroxyl, a carboxyl, or a sulfhydryl. This modification allows phase II, the conjugation, or joining, of the exogenous molecule with an endogenous molecule (one naturally found in the…
OriGene - POLR1C (NM 203290) Human ProteinOriGene - POLR1C (NM 203290) Human Protein
Recombinant protein of human polymerase (RNA) I polypeptide C, 30kDa (POLR1C), transcript variant 1, 20 ug available for purchase from OriGene - Your Gene Company.
Protocols and Video Articles Authored by Roberta CroceProtocols and Video Articles Authored by Roberta Croce
Roberta Croce is the author of this article in the Journal of Visualized Experiments: In Vitro Reconstitution of Light-harvesting Complexes of Plants and Green Algae
Rhodopseudomonas palustrisRhodopseudomonas palustris
Hartmut MichelHartmut Michel
Johann DeisenhoferJohann Deisenhofer
Photosynthetic reaction centrePhotosynthetic reaction centre
Biological pigmentBiological pigment
Photosynthetic reaction centre protein familyPhotosynthetic reaction centre protein family
Klaus SchultenKlaus Schulten
SymbiodiniumSymbiodinium
List of MeSH codes (D08)List of MeSH codes (D08)
Transmembrane proteinTransmembrane protein
Transporter Classification DatabaseTransporter Classification Database
List of biophysically important macromolecular crystal structuresList of biophysically important macromolecular crystal structures
HADHBHADHB
BCKDHABCKDHA
Template:Multienzyme complexesTemplate:Multienzyme complexes
Tryptophan synthaseTryptophan synthase
Fatty acid synthaseFatty acid synthase
Bacterial antenna complexBacterial antenna complex
Light-dependent reactionsLight-dependent reactions
Site-directed spin labelingSite-directed spin labeling
Ycf9 protein domainYcf9 protein domain
Light-harvesting complexLight-harvesting complex
Evolution of photosynthesisEvolution of photosynthesis
Cytochrome b559Cytochrome b559
Plant evolutionPlant evolution
Cytochrome b6f complexCytochrome b6f complex
High potential iron-sulfur proteinHigh potential iron-sulfur protein
CoRR hypothesisCoRR hypothesis
MetabolismMetabolism
PhotosystemPhotosystem
Food webFood web
Codon degeneracyCodon degeneracy
نوبل انعام برائے کیمیا وصول کنندگان کی فہرست - آزاد دائرۃ المعارف، ویکیپیڈیانوبل انعام برائے کیمیا وصول کنندگان کی فہرست - آزاد دائرۃ المعارف، ویکیپیڈیا
RetinalRetinal
வேதியியலுக்கான நோபல் பரிசு பெற்றவர்கள் - தமிழ் விக்கிப்பீடியாவேதியியலுக்கான நோபல் பரிசு பெற்றவர்கள் - தமிழ் விக்கிப்பீடியா
HemoglobinHemoglobin
اکسیژن - ویکی‌پدیا، دانشنامهٔ آزاداکسیژن - ویکی‌پدیا، دانشنامهٔ آزاد
Purple bacteriaPurple bacteria
AntioxidantAntioxidant
PhotosynthesisPhotosynthesis
HabitatHabitat
Bacterial phylaBacterial phyla
Magnesium in biologyMagnesium in biology
Mass spectrometryMass spectrometry
NutritionNutrition
Lista över nobelpristagare i kemiLista över nobelpristagare i kemi
Coenzyme Q - cytochrome c reductaseCoenzyme Q - cytochrome c reductase
PlantPlant
Cambrian explosionCambrian explosion
G proteinG protein
Properties of waterProperties of water
Respiratory systemRespiratory system
Adenosine triphosphateAdenosine triphosphate
வேதியியலுக்கான நோபல் பரிசு - தமிழ் விக்கிப்பீடியாவேதியியலுக்கான நோபல் பரிசு - தமிழ் விக்கிப்பீடியா
Natural productNatural product
BiosignatureBiosignature
Arabidopsis thalianaArabidopsis thaliana
Electrochemical gradientElectrochemical gradient
AnatomyOrganismsChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPhenomena and ProcessesDisciplines and OccupationsTechnology, Industry, AgricultureInformation ScienceHealth Care
Photosynthetic Reaction Center Complex ProteinsRhodobacter sphaeroidesLight-Harvesting Protein ComplexesBacteriochlorophyllsRhodopseudomonasPhotosystem II Protein ComplexElectron TransportPhotosynthesisChlorophyllPheophytinsPhotosystem I Protein ComplexLightCyanobacteriaCytochromes c2ChlorobiQuinonesSpectrophotometryEnergy TransferSpinacia oleraceaRhodobacterBacterial ProteinsProteobacteriaOxidation-ReductionAcidiphiliumHyphomicrobiaceaeElectronsPhotochemistryBacterial ChromatophoresMolecular Sequence DataChlorobiumUbiquinoneAmino Acid SequenceEuglenaKineticsNonheme Iron ProteinsRhodospirillaceaeDiuronSpectrum AnalysisBacteriochlorophyll AProtonsChromatiaceaeModels, MolecularRhodobacter capsulatusCytochrome c GroupRhodovulumProtein ConformationElectrochemistryChromatiumThermodynamicsElectron Spin Resonance SpectroscopyElectrophoresis, Polyacrylamide GelModels, ChemicalIron-Sulfur ProteinsCytochromesStatic ElectricityBenzoquinonesNuclear Pore Complex ProteinsCrystallography, X-RayHydrogen BondingHemeBinding SitesBacteriaMutagenesis, Site-DirectedMembrane ProteinsTemperatureDimethylaminesChloroplastsWaterModels, TheoreticalMolecular StructureHydrogen-Ion ConcentrationMacromolecular SubstancesGenes, BacterialBase Sequence
Snapshots of a photosynthetic reaction centreSnapshots of a photosynthetic reaction centre
JCM 6170 Strain Passport - StrainInfoJCM 6170 Strain Passport - StrainInfo
Antievolution.org - Antievolution.org Discussion Board -Topic::The Origins of PhotosynthesisAntievolution.org - Antievolution.org Discussion Board -Topic::The Origins of Photosynthesis
Publications • Prof. Dr. Klaus Möbius • Department of PhysicsPublications • Prof. Dr. Klaus Möbius • Department of Physics
Crystal structure of the complex between the photosynthetic reaction center and the light-harvesting antenna core proteins ...Crystal structure of the complex between the photosynthetic reaction center and the light-harvesting antenna core proteins ...
Photosynthetic Reaction Center Complex Proteins | Profiles RNSPhotosynthetic Reaction Center Complex Proteins | Profiles RNS
Probing the dynamics of photosynthetic membranes with fluorescence recovery after photobleachingProbing the dynamics of photosynthetic membranes with fluorescence recovery after photobleaching
Flexibility in photosynthetic electron transport: a newly identified chloroplast oxidase involved in chlororespirationFlexibility in photosynthetic electron transport: a newly identified chloroplast oxidase involved in chlororespiration
Interference of electron transport inhibitors with desaturation of monogalactosyl diacylglycerol in intact chloroplasts.Interference of electron transport inhibitors with desaturation of monogalactosyl diacylglycerol in intact chloroplasts.
MEDLINE - Resultado p gina 1 MEDLINE - Resultado p gina 1
Whats New for 2004 MeSH. NLM Technical Bulletin. 2003 Nov-DecWhat's New for 2004 MeSH. NLM Technical Bulletin. 2003 Nov-Dec
Photosynthetic reaction centre - WikipediaPhotosynthetic reaction centre - Wikipedia
Iron-sulfur centers in the photosynthetic reaction center complex from Chlorobium vibrioforme. Differences from and...Iron-sulfur centers in the photosynthetic reaction center complex from Chlorobium vibrioforme. Differences from and...
Structure Cluster - 1DXR: Photosynthetic reaction center from Rhodopseudomonas viridis - His L168 Phe mutant ...Structure Cluster - 1DXR: Photosynthetic reaction center from Rhodopseudomonas viridis - His L168 Phe mutant ...
Crystallization and preliminary x-ray diffraction data of the cryptomonad biliprotein phycocyanin-645 from a Chroomonas spec. |...Crystallization and preliminary x-ray diffraction data of the cryptomonad biliprotein phycocyanin-645 from a Chroomonas spec. |...
Rhodopseudomonas palustris - WikipediaRhodopseudomonas palustris - Wikipedia
Enhanced photocurrent production by bio-dyes of photosynthetic macromolecules on designed TiO 2 film | Scientific ReportsEnhanced photocurrent production by bio-dyes of photosynthetic macromolecules on designed TiO 2 film | Scientific Reports
Production of a Blue Pigment (Glaukothalin) by Marine Rheinheimera spp.Production of a Blue Pigment (Glaukothalin) by Marine Rheinheimera spp.
SCOPe 2.07: Structural Classification of Proteins - extendedSCOPe 2.07: Structural Classification of Proteins - extended
Cytochromes f | Profiles RNSCytochromes f | Profiles RNS
View the content page [c]View the content page [c]
Institutes of Energy and the Environment (IEE) - Research Output - Penn StateInstitutes of Energy and the Environment (IEE) - Research Output - Penn State
Photosystem I complex | SpringerLinkPhotosystem I complex | SpringerLink
2011 - Publications - Department of Physics and astronomy, Faculty of Sciences, Vrije Universiteit Amsterdam2011 - Publications - Department of Physics and astronomy, Faculty of Sciences, Vrije Universiteit Amsterdam
IUCr) Novel approaches for the lipid sponge phase crystallization of the Rhodobacter sphaeroides photosynthetic reaction centerIUCr) Novel approaches for the lipid sponge phase crystallization of the Rhodobacter sphaeroides photosynthetic reaction center
Johann Deisenhofer - WikipediaJohann Deisenhofer - Wikipedia
RCSB PDB - 1DXR: Photosynthetic reaction center from Rhodopseudomonas viridis - His L168 Phe mutant (terbutryn...RCSB PDB - 1DXR: Photosynthetic reaction center from Rhodopseudomonas viridis - His L168 Phe mutant (terbutryn...
Principles of bioenergeticsPrinciples of bioenergetics
Photosystem II - Proteopedia, life in 3DPhotosystem II - Proteopedia, life in 3D
Hartmut Michel : Wikis (The Full Wiki)Hartmut Michel : Wikis (The Full Wiki)
Phenotype of homoplasmic Δycf3 plants. (A) A mutant p | Open-iPhenotype of homoplasmic Δycf3 plants. (A) A mutant p | Open-i
Spectroscopic characterization of quinone-site mutants of the bacterial photosynthetic reaction center<...Spectroscopic characterization of quinone-site mutants of the bacterial photosynthetic reaction center<...
Diverse arrangement of photosynthetic gene clusters in aerobic anoxygenic phototrophic bacteria. - PubMed - NCBIDiverse arrangement of photosynthetic gene clusters in aerobic anoxygenic phototrophic bacteria. - PubMed - NCBI
Frontiers | Small One-Helix Proteins Are Essential for Photosynthesis in Arabidopsis | Plant ScienceFrontiers | Small One-Helix Proteins Are Essential for Photosynthesis in Arabidopsis | Plant Science
AnatomyOrganismsChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPhenomena and ProcessesDisciplines and OccupationsTechnology, Industry, AgricultureInformation ScienceHealth Care
Photosynthetic Reaction Center Complex ProteinsRhodobacter sphaeroidesLight-Harvesting Protein ComplexesBacteriochlorophyllsRhodopseudomonasPhotosystem II Protein ComplexElectron TransportPhotosynthesisChlorophyllPheophytinsPhotosystem I Protein ComplexLightCyanobacteriaCytochromes c2ChlorobiQuinonesSpectrophotometryEnergy TransferSpinacia oleraceaRhodobacterBacterial ProteinsProteobacteriaOxidation-ReductionAcidiphiliumHyphomicrobiaceaeElectronsPhotochemistryBacterial ChromatophoresMolecular Sequence DataChlorobiumUbiquinoneAmino Acid SequenceEuglenaKineticsNonheme Iron ProteinsRhodospirillaceaeDiuronSpectrum AnalysisBacteriochlorophyll AProtonsChromatiaceaeModels, MolecularRhodobacter capsulatusCytochrome c GroupRhodovulumProtein ConformationElectrochemistryChromatiumThermodynamicsElectron Spin Resonance SpectroscopyElectrophoresis, Polyacrylamide GelModels, ChemicalIron-Sulfur ProteinsCytochromesStatic ElectricityBenzoquinonesNuclear Pore Complex ProteinsCrystallography, X-RayHydrogen BondingHemeBinding SitesBacteriaMutagenesis, Site-DirectedMembrane ProteinsTemperatureDimethylaminesChloroplastsWaterModels, TheoreticalMolecular StructureHydrogen-Ion ConcentrationMacromolecular SubstancesGenes, BacterialBase Sequence
RhodobacterCyanobacteriaAlgaeMoleculesThylakoid membraneMolecularMultienzyme ComplexesMetabolismSubunitAbsorptionAmino AcidsChloroplastsSpectroscopyFunctioning of the photosynthetic apparatusOxygenFingerprintCarbon dioxideElectron TransporThylakoidsBacterial reactionAntennaPhotosystem II reaction centreSulfurSolar energyTransmembranePhotochemical reactionsMembrane-bound protein complexesMembranes and isolatedBoundEukaryotesLightPigment-protein complexBacteriochlorophyllCarotenoidsGenomeMoleculeParamagneticExcitation
Rhodobacter5
Cyanobacteria6
Algae4
Molecules19
  • A reaction center is laid out in such a way that it captures the energy of a photon using pigment molecules and turns it into a usable form. (wikipedia.org)
  • Once the light energy has been absorbed directly by the pigment molecules, or passed to them by resonance transfer from a surrounding light-harvesting complex, they release two electrons into an electron transport chain. (wikipedia.org)
  • Indeed, this treatment induced changes in the LH2 absorption spectrum related to the disruption of the interaction of B800 molecules with the LH2 protein. (asm.org)
  • The spectroscopic data are analyzed by state-of-the-art quantum-chemical methods to determine the electronic and geometrical structures (distances and orientations) of the molecules involved in the biological process, including their conformational changes during the reaction. (fu-berlin.de)
  • The main goal of the research projects is to better understand the complex physical and chemical interactions between nanoscale protein molecules and liquid solvents or solid sugar-glass matrices in which they are embedded. (fu-berlin.de)
  • Quantum-mechanical effects enable a plant's photosystem to simultaneously sample all the potential energy pathways from pigment molecules to reaction centers and choose the most efficient one. (lbl.gov)
  • From our investigation, we conclude that the protein environment in the reaction center works collectively to keep the fluctuations of excited electronics states of pigment molecules in phase, and therefore protects quantum coherence," says Hohjai Lee, a member of Fleming's research group and co-author of a recent paper in S c ience describing their work. (lbl.gov)
  • In the high-frequency/high-field EPR region, sub-micromolar concentrations of nitroxide spin-labeled molecules are now sufficient to characterize reaction intermediates of complex biomolecular processes. (tu-dortmund.de)
  • This ET reaction has been mimicked by using organic "diad" molecules consisting of a covalently linked, light-activated electron donor, such as a porphyrin, and an electron acceptor, such as a quinone, for several decades with considerable success ( 7 - 10 ). (pnas.org)
  • Nanoscale objects in solution (such as proteins, enzymes, and DNA) are continually bombarded by thermally agitated molecules of solvent. (stanford.edu)
  • Using a variety of approaches, the position update and consequent feedback application time has been made fast enough to trap individual fluorescently labeled protein molecules in solution. (stanford.edu)
  • When this was first done, these molecules (as small as 10 nm in diameter) were the first proteins trapped in solution and the smallest objects ever trapped in solution. (stanford.edu)
  • Coupling to the environment (for example, to solvent molecules or a protein binding pocket) leads to dephasing of these coherences across the molecules. (cloudfront.net)
  • The pigment molecules cluster together in what is called a photosynthetic unit. (encyclopedia.com)
  • The preface of this book sets out the tenet that biological reactions cannot be understood except through the structure of participating molecules. (quantum-mind.co.uk)
  • Protein molecules are polymers built up out of the 20 amino acids. (quantum-mind.co.uk)
  • Where there are holes in the interior of the protein , these are usually occupied by closely bound water molecules, which are here regarded as integral parts of the protein . (quantum-mind.co.uk)
  • Carotenoid molecules suppress damaging photochemical reactions, particularly those including oxygen , which exposure to sunlight can cause. (academic.ru)
  • As these molecules are vital for life, metabolic reactions either focus on making these molecules during the construction of cells and tissues, or by breaking them down and using them as a source of energy, by their digestion. (wikipedia.org)
Thylakoid membrane7
Molecular11
  • A) Molecular structure of the LH1-RC complex. (or.jp)
  • Molecular excitations, either originating directly from sunlight or transferred as excitation energy via light-harvesting antenna systems, give rise to electron transfer reactions along the path of a series of protein-bound co-factors. (wikipedia.org)
  • Matthews BW (1971) Determination of molecular weight from protein crystals. (springer.com)
  • The molecular biology and biochemistry of the complex are discussed in relation to the structure and function of the individual components. (springer.com)
  • We use a variety of approaches - molecular genetics, protein engineering, confocal fluorescence microscopy, liquid chromatography as well as structural and spectroscopic methods. (edu.au)
  • Besides giving insight into the suitability of these complexes for molecular-scale photovoltaics, our work suggests a new possible biological function for the vibrational environment of photosynthetic reaction centres, namely, to reduce the intrinsic current noise for regulatory processes. (rsc.org)
  • In discovering the signal that fingered quantum mechanics as the secret to the speed of photosynthetic energy transfer, he and his group used a technique they developed called two-dimensional electronic spectroscopy (2DES), which enabled them to follow the flow of light-induced excitation energy through molecular complexes with femtosecond temporal resolution. (lbl.gov)
  • PELDOR techniques applied to frozen-solution samples of doubly spin-labeled proteins allow for molecular distance measurements ranging up to about 100 Å. (tu-dortmund.de)
  • Integral Membrane Proteins Significantly Decrease the Molecular Motion in Lipid Bilayers: A Deuteron NMR Relaxation Study of Membranes Containing Myelin Proteolipid Apoprotein, Proc. (bio-cat.ru)
  • The antennae take solar energy and create a molecular excitation, and in the reaction center, the excitation is converted to a charge separation," Ogilvie said. (eurekalert.org)
  • VMD is a molecular graphics program designed for the display and analysis of molecular assemblies, in particular biopolymers such as proteins and nucleic acids. (uiuc.edu)
Multienzyme Complexes1
  • In fact, three classes of these multienzyme complexes have been characterized, one specific for pyruvate , a second specific for 2-oxoglutarate and a third specificbranched-chain α-keto acids. (wikidoc.org)
Metabolism5
  • Pubmed ID: 12455693 The unicellular green alga Chlamydomonas reinhardtii is a valuable model for studying metal metabolism in a photosynthetic background. (jove.com)
  • The three main purposes of metabolism are the conversion of food/fuel to energy to run cellular processes, the conversion of food/fuel to building blocks for proteins, lipids, nucleic acids, and some carbohydrates, and the elimination of nitrogenous wastes. (wikipedia.org)
  • Metabolism is usually divided into two categories: catabolism, the breaking down of organic matter for example, the breaking down of glucose to pyruvate, by cellular respiration, and anabolism, the building up of components of cells such as proteins and nucleic acids. (wikipedia.org)
  • The chemical reactions of metabolism are organized into metabolic pathways, in which one chemical is transformed through a series of steps into another chemical, by a sequence of enzymes. (wikipedia.org)
  • Many proteins are enzymes that catalyze the chemical reactions in metabolism. (wikipedia.org)
Subunit9
Absorption8
Amino Acids4
Chloroplasts4
Spectroscopy4
Functioning of the photosynthetic apparatus1
  • To investigate the consequences of the acclimation strategies adopted by Arabidopsis thaliana, we have assessed the functioning of the photosynthetic apparatus in plants with very different chloroplast compositions. (ox.ac.uk)
Oxygen5
Fingerprint1
Carbon dioxide1
Electron Transpor1
Thylakoids2
Bacterial reaction3
Antenna6
Photosystem II reaction centre1
Sulfur3
Solar energy1
Transmembrane4
Photochemical reactions1
  • By combining EPR and optical spectroscopies, we cover a wide time-scale of photochemical reactions, ranging from tens of femtoseconds to tens of seconds. (fu-berlin.de)
Membrane-bound protein complexes1
Membranes and isolated1
Bound7
Eukaryotes2
Light25
Pigment-protein complex1
Bacteriochlorophyll4
Carotenoids1
Genome5
Molecule4
  • A step further in this field is the recent development of single-molecule techniques that allow measurement of the photocurrent through individual PRC complexes. (rsc.org)
  • The HADHB protein catalyzes the final step of beta-oxidation, in which 3-ketoacyl CoA is cleaved by the thiol group of another molecule of Coenzyme A . The thiol is inserted between C-2 and C-3, which yields an acetyl CoA molecule and an acyl CoA molecule, which is two carbons shorter. (wikipedia.org)
  • The folding of protein is mainly driven by the need to pack hydrophobic side chains into the interior of the molecule, creating a hydrophobic core and a hydrophylic surface. (quantum-mind.co.uk)
  • At this point the Q B will leave the complex and establish a gradient of protons across the bacterial membrane which will then be used by other proteins to generate the cell's energy currency, a molecule called ATP. (iycr2014.org)
Paramagnetic1
  • An important additional advantage of EPR over NMR is the ability to detect and characterize even short-lived paramagnetic reaction intermediates (down to a lifetime of a few ns). (tu-dortmund.de)
Excitation4