2012
Distinct Disulfide Isomers of μ‑Conotoxins KIIIA and KIIIB Block Voltage-Gated Sodium Channels
Khoo KK, Gupta K, Green BR, Zhang MM, Watkins M, Olivera BM, Balaram P, Yoshikami D, Bulaj G, Norton RS. Distinct Disulfide Isomers of μ‑Conotoxins KIIIA and KIIIB Block Voltage-Gated Sodium Channels. Biochemistry 2012, 51: 9826-9835. PMID: 23167564, PMCID: PMC4131687, DOI: 10.1021/bi301256s.Peer-Reviewed Original ResearchMeSH KeywordsChromatography, High Pressure LiquidCloning, MolecularConotoxinsDisulfidesIon Channel GatingIsomerismMass SpectrometryNuclear Magnetic Resonance, BiomolecularOxidation-ReductionSodium ChannelsConceptsΜ-Conotoxin KIIIADisulfide connectivityCollision-induced dissociation fragmentationDisulfide isomersNuclear magnetic resonance dataNative disulfide connectivityDisulfide patternVenom-derived peptidesDisulfide bond connectivitySame disulfide connectivityOxidative foldingDissociation fragmentationMagnetic resonance dataBond connectivityMultiple disulfide bondsMinor productsMajor isomerSolution structureActive peptidesIsomersΜ-conotoxinsResonance dataKIIIAVenom of ConusDisulfide bondsLipopeptides from the Banyan Endophyte, Bacillus subtilis K1: Mass Spectrometric Characterization of a Library of Fengycins
Pathak KV, Keharia H, Gupta K, Thakur SS, Balaram P. Lipopeptides from the Banyan Endophyte, Bacillus subtilis K1: Mass Spectrometric Characterization of a Library of Fengycins. Journal Of The American Society For Mass Spectrometry 2012, 23: 1716-1728. PMID: 22847390, DOI: 10.1007/s13361-012-0437-4.Peer-Reviewed Original ResearchMeSH KeywordsBacillus subtilisBacterial ProteinsChromatography, High Pressure LiquidLipopeptidesMass SpectrometryPeptides, CyclicConceptsHigh-performance liquid chromatographyMass spectrometryIonization mass spectrometric studyHigh-resolution mass spectrometryDiagnostic fragment ionsResolution mass spectrometryMass spectrometric characterizationMass spectrometric studyChain length variationReversed-phase high-performance liquid chromatographyMS/MS analysisLaser desorption ionizationMass spectrometric analysisLinear precursorsFragment ionsMacrocyclic ringFatty acid chainsPerformance liquid chromatographySpectrometric characterizationGlu replacementSpectrometric studyAcid moietyComplex mixturesDesorption ionizationFatty acid moieties
2010
Disulfide Bond Assignments by Mass Spectrometry of Native Natural Peptides: Cysteine Pairing in Disulfide Bonded Conotoxins
Gupta K, Kumar M, Balaram P. Disulfide Bond Assignments by Mass Spectrometry of Native Natural Peptides: Cysteine Pairing in Disulfide Bonded Conotoxins. Analytical Chemistry 2010, 82: 8313-8319. PMID: 20843009, DOI: 10.1021/ac101867e.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsChromatography, High Pressure LiquidConotoxinsConus SnailCysteineDisulfidesPeptidesSpectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationConceptsS bond cleavageBond cleavageNatural peptidesDisulfide bondsProduct ion yieldsMass spectral fragmentationDisulfide bond assignmentsDisulfide pairingFragment ionsStructure elucidationPeptide backboneBond assignmentDissociation conditionsMass spectrometryMultiple disulfide bondsCysteine pairingsSpectral fragmentationPossible disulfideMultiple cysteine residuesNative peptideAnalytical methodologyBondsCorrect disulfide pairingIon yieldFurther fragmentation