2005
New Linear High-Valent Tetranuclear Manganese-Oxo Cluster Relevant to the Oxygen-Evolving Complex of Photosystem II with Oxo, Hydroxo, and Aqua Coordinated to a Single Mn(IV)
Chen, Collomb M, Duboc C, Blondin G, Rivière E, Faller J, Crabtree R, Brudvig G. New Linear High-Valent Tetranuclear Manganese-Oxo Cluster Relevant to the Oxygen-Evolving Complex of Photosystem II with Oxo, Hydroxo, and Aqua Coordinated to a Single Mn(IV). Inorganic Chemistry 2005, 44: 9567-9573. PMID: 16323946, DOI: 10.1021/ic051462m.Peer-Reviewed Original ResearchConceptsGround stateSpin statesFirst excited spin stateExcited spin statesSpin-triplet stateLarge energy gapOxygen-Evolving ComplexMn–Mn distanceDiamagnetic ground stateEnergy gapVariable-temperature magnetic susceptibility dataX-ray powder diffractionTriplet stateMagnetic susceptibility dataTetranuclear manganeseMnIV ionsHigh‐Spin Chloro Mononuclear MnIII Complexes: A Multifrequency High‐Field EPR Study
Mantel C, Chen H, Crabtree R, Brudvig G, Pécaut J, Collomb M, Duboc C. High‐Spin Chloro Mononuclear MnIII Complexes: A Multifrequency High‐Field EPR Study. ChemPhysChem 2005, 6: 541-546. PMID: 15799481, DOI: 10.1002/cphc.200400484.Peer-Reviewed Original ResearchConceptsElectronic propertiesLigand field strengthHigh-Field EPR StudyPorphyrinic systemsTridentate ligandMnIII complexesDistorted octahedronLigands decreasesSolid stateJahn-Teller distortionPrevious complexesStructural characterizationCrystallographic dataEPR studiesMultifrequency EPRManganese ionsComplexesOctahedraTetragonal distortionE termDifferent temperaturesAnionsEPRLigandsProperties
2004
Q-Band EPR of the S2 State of Photosystem II Confirms an S=5/2 Origin of the X-Band g=4.1 Signal
Haddy A, Lakshmi K, Brudvig G, Frank H. Q-Band EPR of the S2 State of Photosystem II Confirms an S=5/2 Origin of the X-Band g=4.1 Signal. Biophysical Journal 2004, 87: 2885-2896. PMID: 15454478, PMCID: PMC1304705, DOI: 10.1529/biophysj.104.040238.Peer-Reviewed Original ResearchMeSH KeywordsElectron Spin Resonance SpectroscopyEthanolLightMicrowavesPhotosystem II Protein ComplexConceptsSame spin systemS2 stateSpin systemsZero-field splitting valuesMiddle Kramers doubletPhotosystem IILight-induced signalsS2 oxidation stateX-bandKramers doubletX-band signalQ-band EPRPSII-enriched membrane fragmentsSplitting valuesLow-field signalMn clusterQ-bandState originEPR signalOxidation stateStateDoubletSpectraSignalsGHz
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 6803Pulsed High-Frequency EPR Study on the Location of Carotenoid and Chlorophyll Cation Radicals in Photosystem II
Lakshmi K, Poluektov O, Reifler M, Wagner A, Thurnauer M, Brudvig G. Pulsed High-Frequency EPR Study on the Location of Carotenoid and Chlorophyll Cation Radicals in Photosystem II. Journal Of The American Chemical Society 2003, 125: 5005-5014. PMID: 12708850, DOI: 10.1021/ja0295671.Peer-Reviewed Original ResearchMeSH KeywordsBeta CaroteneBinding SitesCationsChlorophyllCyanobacteriaDeuteriumElectron Spin Resonance SpectroscopyFerrous CompoundsFree RadicalsLight-Harvesting Protein ComplexesOxidation-ReductionPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexProtein ConformationRhodospirillumConceptsHigh-frequency EPR spectroscopyRelaxation enhancementEPR spectroscopyRelaxation ratePS IIElectron donorChlorophyll cation radicalsSpin-lattice relaxation rateWater oxidation complexFrequency EPR StudyPigment-protein complexesPhotosystem IIGreater relaxation enhancementCarotenoid-binding siteCation radicalsChlorophyll radicalsElectron transferAlternate electron donorsEPR studiesEPR signalDistance estimatesReaction centersRadicalsSpectroscopy
2002
Component B Binding to the Soluble Methane Monooxygenase Hydroxylase by Saturation-Recovery EPR Spectroscopy of Spin-Labeled MMOB
MacArthur R, Sazinsky M, Kühne H, Whittington D, Lippard S, Brudvig G. Component B Binding to the Soluble Methane Monooxygenase Hydroxylase by Saturation-Recovery EPR Spectroscopy of Spin-Labeled MMOB. Journal Of The American Chemical Society 2002, 124: 13392-13393. PMID: 12418885, DOI: 10.1021/ja0279904.Peer-Reviewed Original ResearchBinding SitesElectron Spin Resonance SpectroscopyKineticsMethylococcus capsulatusModels, MolecularMultienzyme ComplexesOxygenasesProtein Conformation
2001
Pulsed electron paramagnetic resonance methods for macromolecular structure determination
Lakshmi K, Brudvig G. Pulsed electron paramagnetic resonance methods for macromolecular structure determination. Current Opinion In Structural Biology 2001, 11: 523-531. PMID: 11785751, DOI: 10.1016/s0959-440x(00)00242-6.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAzurinElectron Spin Resonance SpectroscopyMacromolecular SubstancesModels, MolecularNitric Oxide SynthaseNitric Oxide Synthase Type IIIPhotosynthetic Reaction Center Complex ProteinsConceptsElectron paramagnetic resonance methodHigh-field EPRParamagnetic resonance methodMacromolecular structure determinationStructure elucidationEPR distance measurementsMacromolecular systemsStructure determinationStructure/function relationshipsRecent applicationsResonance methodMicrowave technologyFunction relationshipsEPRDeterminationRecent developmentsReview articlePowerful toolElucidationFactors that determine the unusually low reduction potential of cytochrome c550 in cyanobacterial photosystem II
Vrettos J, Reifler M, Kievit O, Lakshmi K, de Paula J, Brudvig G. Factors that determine the unusually low reduction potential of cytochrome c550 in cyanobacterial photosystem II. JBIC Journal Of Biological Inorganic Chemistry 2001, 6: 708-716. PMID: 11681704, DOI: 10.1007/s007750100249.Peer-Reviewed Original ResearchConceptsPCC 6803 photosystem IILow reduction potentialReduction potentialPyrolytic graphite edge electrodeElectron paramagnetic resonance spectroscopySquare wave voltammetryDirect electrochemical measurementsParamagnetic resonance spectroscopyBis-histidine axial ligationHeme reduction potentialCyanobacterial photosystem IIResonance Raman spectraPhotosystem IIWave voltammetryElectrode surfaceElectrochemistry experimentsElectrochemical measurementsElectrochemical valuesAxial ligationSolvent waterCyt c550Solvent exposureRedox titrationPeak separationPSII preparationsPhotosynthetic Water Oxidation in Cytochromeb 559 Mutants Containing a Disrupted Heme-binding Pocket*
Morais F, Kühn K, Stewart D, Barber J, Brudvig G, Nixon P. Photosynthetic Water Oxidation in Cytochromeb 559 Mutants Containing a Disrupted Heme-binding Pocket*. Journal Of Biological Chemistry 2001, 276: 31986-31993. PMID: 11390403, DOI: 10.1074/jbc.m103935200.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBase SequenceCarrier ProteinsChlamydomonas reinhardtiiCytochrome b GroupDNA PrimersElectron Spin Resonance SpectroscopyHeme-Binding ProteinsHemeproteinsMutagenesis, Site-DirectedMutationOxidation-ReductionPhotosynthesisPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexWaterConceptsPhotosynthetic oxygen evolutionMethionine mutantsWild typeAlpha subunitLight-saturated ratePhotosystem two complexWild-type levelsHeme of cytochromePhotosynthetic water oxidationHeme-binding pocketOxygen evolutionChloroplast mutantsPSII supercomplexesHistidine axial ligandsChlamydomonas reinhardtiiGlutamine mutantTyrosine mutantsMutantsType levelsRedox roleHemeSubunitsOxygen evolution activityTyrosineComplexesHigh-Frequency EPR Study of a New Mononuclear Manganese(III) Complex: [(terpy)Mn(N3)3] (terpy = 2,2‘:6‘,2‘ ‘-Terpyridine)
Limburg J, Vrettos J, Crabtree R, Brudvig G, de Paula J, Hassan A, Barra A, Duboc-Toia C, Collomb M. High-Frequency EPR Study of a New Mononuclear Manganese(III) Complex: [(terpy)Mn(N3)3] (terpy = 2,2‘:6‘,2‘ ‘-Terpyridine). Inorganic Chemistry 2001, 40: 1698-1703. PMID: 11261982, DOI: 10.1021/ic001118j.Peer-Reviewed Original ResearchMeSH KeywordsCrystallography, X-RayElectron Spin Resonance SpectroscopyManganese CompoundsModels, MolecularMolecular StructureOrganometallic CompoundsPyridinesUse of EPR Spectroscopy to Study Macromolecular Structure and Function
Biswas R, KÜhne H, Brudvig G, Gopalan V. Use of EPR Spectroscopy to Study Macromolecular Structure and Function. Science Progress 2001, 84: 45-68. PMID: 11382137, PMCID: PMC10367463, DOI: 10.3184/003685001783239050.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsElectron Spin Resonance SpectroscopyHumansMutagenesis, Site-DirectedProtein Structure, QuaternarySpin LabelsConceptsElectron paramagnetic resonance spectroscopyProtein-nucleic acid complexesSpin-labeling reagentParamagnetic resonance spectroscopySpin labelsEPR spectroscopyAcid complexesBiological macromoleculesEPR spectraSite-specific substitutionMacromolecular structureResonance spectroscopyNucleic acidsSpectroscopyRecent applicationsStructural aspectsCommercial availabilityMacromoleculesCysteine residuesReagentsAdvent of techniquesStructure-function correlatesExperimental strategiesComplexesPowerful toolCarotenoid Photooxidation in Photosystem II
Tracewell C, Vrettos J, Bautista J, Frank H, Brudvig G. Carotenoid Photooxidation in Photosystem II. Archives Of Biochemistry And Biophysics 2001, 385: 61-69. PMID: 11361027, DOI: 10.1006/abbi.2000.2150.Peer-Reviewed Original ResearchConceptsPhotosystem IIElectron transfer reactionsPhotosynthetic reaction centersWater oxidationLight-harvesting pigmentsCarotenoid cationOxidizing intermediatesElectron transferRedox roleBacterial photosynthesisReaction centersPhysical methodsCationsPhotooxidationCarotenoid compositionRedoxOxidationIntermediatesAlternate pathwayCarotenoidsMinireviewReactionPhotoprotectionPossible rolePigments
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 kineticsAssignment of the Q y Absorbance Bands of Photosystem II Chromophores by Low-Temperature Optical Spectroscopy of Wild-Type and Mutant Reaction Centers †
Stewart D, Nixon P, Diner B, Brudvig G. Assignment of the Q y Absorbance Bands of Photosystem II Chromophores by Low-Temperature Optical Spectroscopy of Wild-Type and Mutant Reaction Centers †. Biochemistry 2000, 39: 14583-14594. PMID: 11087414, DOI: 10.1021/bi001246j.Peer-Reviewed Original ResearchMeSH KeywordsBacteriochlorophyllsBenzoquinonesCold TemperatureCyanobacteriaElectron Spin Resonance SpectroscopyFree RadicalsFreezingGlutamineHistidineLight-Harvesting Protein ComplexesMutagenesis, Site-DirectedOxidation-ReductionPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexSpectrophotometryTyrosineConceptsAbsorbance bandPhotosystem IIHydrogen bonding environmentOptical spectroscopyReaction center chromophoresRedox-active cofactorsDouble difference spectraLow temperature optical spectroscopyNumber of chromophoresRedox-active quinonesMutant reaction centersRedox stateRC chromophoresAxial ligandsCryogenic optical spectroscopyChromophore positionProtein environmentPSII preparationsSpectral assignmentsElectrochromic effectAccessory ChlElectronic structureChromophoreChromophore interactionsPhotosynthetic RCs
1999
Location of the Iron−Sulfur Clusters FA and FB in Photosystem I: An Electron Paramagnetic Resonance Study of Spin Relaxation Enhancement of P700 + †
Lakshmi K, Jung Y, Golbeck J, Brudvig G. Location of the Iron−Sulfur Clusters FA and FB in Photosystem I: An Electron Paramagnetic Resonance Study of Spin Relaxation Enhancement of P700 + †. Biochemistry 1999, 38: 13210-13215. PMID: 10529193, DOI: 10.1021/bi9910777.Peer-Reviewed Original ResearchOrientation of the Tetranuclear Manganese Cluster and Tyrosine Z in the O2-Evolving Complex of Photosystem II: An EPR Study of the S2YZ • State in Oriented Acetate-Inhibited Photosystem II Membranes †
Lakshmi K, Eaton S, Eaton G, Brudvig G. Orientation of the Tetranuclear Manganese Cluster and Tyrosine Z in the O2-Evolving Complex of Photosystem II: An EPR Study of the S2YZ • State in Oriented Acetate-Inhibited Photosystem II Membranes †. Biochemistry 1999, 38: 12758-12767. PMID: 10504246, DOI: 10.1021/bi990780s.Peer-Reviewed Original ResearchElectron Spin Resonance SpectroscopyManganeseOxygenPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexTyrosineCompetitive 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 ResearchA Functional Model for O-O Bond Formation by the O2-Evolving Complex in Photosystem II
Limburg J, Vrettos J, Liable-Sands L, Rheingold A, Crabtree R, Brudvig G. A Functional Model for O-O Bond Formation by the O2-Evolving Complex in Photosystem II. Science 1999, 283: 1524-1527. PMID: 10066173, DOI: 10.1126/science.283.5407.1524.Peer-Reviewed Original ResearchConceptsMolecular oxygenPhotosystem IIO bond formationPhotosynthetic water oxidationWater oxidationManganese dimerBond formationOxygen atomsActive siteIsotope labelingManganese ionsOxygenPhotosynthesisWaterSodium hypochloriteOxidationIonsFormationAtomsDimersComplexesO2Functional modelConversionHypochloriteMapping RNA−Protein Interactions in Ribonuclease P from Escherichia coli Using Electron Paramagnetic Resonance Spectroscopy †
Gopalan V, Kühne H, Biswas R, Li H, Brudvig G, Altman S. Mapping RNA−Protein Interactions in Ribonuclease P from Escherichia coli Using Electron Paramagnetic Resonance Spectroscopy †. Biochemistry 1999, 38: 1705-1714. PMID: 10026248, DOI: 10.1021/bi9807106.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceBacterial ProteinsBinding SitesComputer SimulationElectron Spin Resonance SpectroscopyEndoribonucleasesEscherichia coliEscherichia coli ProteinsModels, MolecularMolecular Sequence DataMutagenesis, Site-DirectedProtein FoldingRibonuclease PRibonucleoproteinsRNA, BacterialRNA, CatalyticSpin LabelsStructure-Activity RelationshipConceptsM1 RNAC5 proteinRibonuclease PCysteine residuesEscherichia coliRNA-protein interfaceCatalytic RNA subunitNative cysteine residuesSulfhydryl-specific reagentsCatalytic ribonucleoproteinRNA subunitHoloenzyme complexRNP complexesProtein cofactorsMutant derivativesDeletion derivativesRNASpin labelsProteinSpectroscopy-based approachRibonucleoproteinResiduesPosition 16Coli
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 Research