2003
Two Redox-Active β-Carotene Molecules in Photosystem II †
Tracewell C, Brudvig G. Two Redox-Active β-Carotene Molecules in Photosystem II †. Biochemistry 2003, 42: 9127-9136. PMID: 12885246, DOI: 10.1021/bi0345844.Peer-Reviewed Original ResearchMeSH KeywordsAdaptation, PhysiologicalBeta CaroteneCyanobacteriaDarknessElectron Spin Resonance SpectroscopyFree RadicalsFreezingLight-Harvesting Protein ComplexesNormal DistributionOxidation-ReductionPhotochemistryPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexSpectroscopy, Near-InfraredSpinacia oleraceaTyrosineConceptsSecondary electron transfer pathwayElectron transfer pathwayElectron paramagnetic resonance spectroscopyElectron transfer reactionsElectron transfer pathParamagnetic resonance spectroscopyHole-hopping mechanismPS II core complexesΒ-carotene moleculesPS II membranesII core complexesPhotosystem IIIR spectroscopyPS IILow temperatureCharge separationElectrostatic interactionsOxygen evolutionResonance spectroscopyLow-temperature illuminationInhibited samplesSpectroscopyEquilibrated statePeak variesSynechocystis PCC 6803
2001
Quantifying the Ion Selectivity of the Ca2+ Site in Photosystem II: Evidence for Direct Involvement of Ca2+ in O2 Formation †
Vrettos J, Stone D, Brudvig G. Quantifying the Ion Selectivity of the Ca2+ Site in Photosystem II: Evidence for Direct Involvement of Ca2+ in O2 Formation †. Biochemistry 2001, 40: 7937-7945. PMID: 11425322, DOI: 10.1021/bi010679z.Peer-Reviewed Original ResearchConceptsOxygen-evolving complexTrivalent metal ionsMetal ionsPSII samplesPhotosystem IISubstrate water moleculesSmall metal ionsO2 evolutionSteady-state enzyme kineticsWater oxidationAqua ionsWater moleculesLewis acidO2 formationIonic radiusIon selectivityKcal/Monovalent ionsIonsExtrinsic polypeptidesFree energyEnzyme kineticsStructural cofactorSr2Activity measurements
2000
Characterization of Carotenoid and Chlorophyll Photooxidation in Photosystem II †
Tracewell C, Cua A, Stewart D, Bocian D, Brudvig G. Characterization of Carotenoid and Chlorophyll Photooxidation in Photosystem II †. Biochemistry 2000, 40: 193-203. PMID: 11141071, DOI: 10.1021/bi001992o.Peer-Reviewed Original ResearchMeSH KeywordsCarotenoidsChlorophyllCyanobacteriaElectron Spin Resonance SpectroscopyFree RadicalsLight-Harvesting Protein ComplexesOxidation-ReductionPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexSpectroscopy, Near-InfraredSpectrum Analysis, RamanSpinacia oleraceaTemperatureThylakoidsConceptsSpinach PSII membranesPSII core complexesPSII membranesIR bandsElectron paramagnetic resonance spectroscopyAccessory chlorophyllPhotosystem IIParamagnetic resonance spectroscopyResonance Raman bandsPrevious spectroscopic studiesCation radicalsRaman difference spectroscopySpectroscopic studiesAlternate electron donorsElectron donorInfrared absorbanceCharacterization of carotenoidsRaman bandsResonance spectroscopyDifference spectroscopyHeme cofactorProtein conformersCore complexDifferent stabilitiesMultiphasic kinetics
1999
Competitive Binding of Acetate and Chloride in Photosystem II †
Kühne H, Szalai V, Brudvig G. Competitive Binding of Acetate and Chloride in Photosystem II †. Biochemistry 1999, 38: 6604-6613. PMID: 10350479, DOI: 10.1021/bi990341t.Peer-Reviewed Original Research
1998
Characterization of the Interaction between Manganese and Tyrosine Z in Acetate-Inhibited Photosystem II †
Szalai V, Kühne H, Lakshmi K, Brudvig G. Characterization of the Interaction between Manganese and Tyrosine Z in Acetate-Inhibited Photosystem II †. Biochemistry 1998, 37: 13594-13603. PMID: 9753446, DOI: 10.1021/bi9813025.Peer-Reviewed Original ResearchCatalase-Free Photosystem II: The O2-Evolving Complex Does Not Dismutate Hydrogen Peroxide †
Sheptovitsky Y, Brudvig G. Catalase-Free Photosystem II: The O2-Evolving Complex Does Not Dismutate Hydrogen Peroxide †. Biochemistry 1998, 37: 5052-5059. PMID: 9548736, DOI: 10.1021/bi972872s.Peer-Reviewed Original ResearchCalcium Binding Studies of Photosystem II Using a Calcium-Selective Electrode †
Grove G, Brudvig G. Calcium Binding Studies of Photosystem II Using a Calcium-Selective Electrode †. Biochemistry 1998, 37: 1532-1539. PMID: 9484223, DOI: 10.1021/bi971356z.Peer-Reviewed Original Research
1997
Fluorescence Quenching by Chlorophyll Cations in Photosystem II †
Schweitzer R, Brudvig G. Fluorescence Quenching by Chlorophyll Cations in Photosystem II †. Biochemistry 1997, 36: 11351-11359. PMID: 9298954, DOI: 10.1021/bi9709203.Peer-Reviewed Original ResearchConceptsFluorescence quenchingPhotosystem IIElectron donorDonor sideElectron paramagnetic resonance spectroscopyRedox-active tyrosinesRedox-active centersCharge-separated stateSteady-state fluorescence quenchingParamagnetic resonance spectroscopyRedox-active componentsElectron donor sideElectron transfer pathwayCytochrome b559Redox stateFluorescence intensityO2-evolving complexPrimary electron donorReversible oxidationChlorophyll cationElectron donationFurther oxidationChlZRapid photooxidationDifferent sample preparationThe Tetranuclear Manganese Cluster in Photosystem II: Location and Magnetic Properties of the S2 State As Determined by Saturation−Recovery EPR Spectroscopy †
Koulougliotis D, Schweitzer R, Brudvig G. The Tetranuclear Manganese Cluster in Photosystem II: Location and Magnetic Properties of the S2 State As Determined by Saturation−Recovery EPR Spectroscopy †. Biochemistry 1997, 36: 9735-9746. PMID: 9245405, DOI: 10.1021/bi970326t.Peer-Reviewed Original ResearchConceptsFirst excited spin stateSpin-lattice relaxationSpin statesMagnetic propertiesExcited spin statesS2-state multiline EPRNuclear spin-lattice relaxationSpin-lattice relaxation propertiesEffective magnetic momentLine shapeUntreated photosystem IIMagnetic momentDifferent spin statesDipolar modelNear resonanceGround spin stateSaturation-recovery EPR spectroscopyNuclear relaxation processesLarmor frequencyOrbach mechanismGreater relaxation enhancementTemperature-dependent enhancementDipole-dipole interactionTetranuclear manganese clusterS2-state multiline EPR signal
1996
Formation and Decay of the S3 EPR Signal Species in Acetate-Inhibited Photosystem II †
Szalai V, Brudvig G. Formation and Decay of the S3 EPR Signal Species in Acetate-Inhibited Photosystem II †. Biochemistry 1996, 35: 1946-1953. PMID: 8639678, DOI: 10.1021/bi952378t.Peer-Reviewed Original ResearchReversible Binding of Nitric Oxide to Tyrosyl Radicals in Photosystem II. Nitric Oxide Quenches Formation of the S3 EPR Signal Species in Acetate-Inhibited Photosystem II†
Szalai V, Brudvig G. Reversible Binding of Nitric Oxide to Tyrosyl Radicals in Photosystem II. Nitric Oxide Quenches Formation of the S3 EPR Signal Species in Acetate-Inhibited Photosystem II†. Biochemistry 1996, 35: 15080-15087. PMID: 8942675, DOI: 10.1021/bi961117w.Peer-Reviewed Original ResearchConceptsS3 EPR signalOxygen-evolving complexMultiline EPR signalEPR signalS2 statePhotosystem IIManganese-depleted photosystem IIS2-state multiline EPR signalRedox-active tyrosinesPhotosystem II samplesRadical EPR signalSignal speciesNitric oxide (NO) bindsTyrosyl radicalsAmmonia resultsReversible bindingOxideYZDipolar interactionsRibonucleotide reductaseIsolation and Characterization of Spinach Photosystem II Membrane-Associated Catalase and Polyphenol Oxidase †
Sheptovitsky Y, Brudvig G. Isolation and Characterization of Spinach Photosystem II Membrane-Associated Catalase and Polyphenol Oxidase †. Biochemistry 1996, 35: 16255-16263. PMID: 8973199, DOI: 10.1021/bi9613842.Peer-Reviewed Original ResearchMeSH KeywordsAmino AcidsCatalaseCatechol OxidaseChloroplastsChromatography, High Pressure LiquidChromatography, Ion ExchangeCopperElectrophoresis, Polyacrylamide GelHot TemperatureIntracellular MembranesKineticsMolecular WeightOxygenOxygen ConsumptionPeptide MappingPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexSpectrophotometrySpinacia oleraceaSubstrate SpecificityConceptsPSII membranesCentre of PSIIUV-visible absorptionO2 evolution activityThylakoid membranesSpinach thylakoid membranesAnion-exchange chromatographyMembrane-associated catalaseHeme enzymesBatch adsorptionHeme catalasesMild heat treatmentHeat treatmentMolecular weightAnion-exchange beadsNative molecular weightPPOIrreversible aggregationGel filtrationFurther manipulationAdsorptionAmino acid compositionTriazoleMembraneChromatography
1995
Spectroscopic evidence for the symmetric location of tyrosines D and Z in photosystem II.
Koulougliotis D, Tang X, Diner B, Brudvig G. Spectroscopic evidence for the symmetric location of tyrosines D and Z in photosystem II. Biochemistry 1995, 34: 2850-6. PMID: 7893698, DOI: 10.1021/bi00009a015.Peer-Reviewed Original Research
1994
Location of chlorophyllZ in photosystem II.
Koulougliotis D, Innes J, Brudvig G. Location of chlorophyllZ in photosystem II. Biochemistry 1994, 33: 11814-22. PMID: 7918399, DOI: 10.1021/bi00205a018.Peer-Reviewed Original ResearchBacteriochlorophyllsChlorophyllCold TemperatureCyanidesDarknessDysprosiumEdetic AcidElectron Spin Resonance SpectroscopyIronLightLight-Harvesting Protein ComplexesManganeseMicrowavesModels, ChemicalOxidation-ReductionPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexSpinacia oleracea