2013
Mammalian Neuronal Sodium Channel Blocker μ‑Conotoxin BuIIIB Has a Structured N‑Terminus That Influences Potency
Kuang Z, Zhang MM, Gupta K, Gajewiak J, Gulyas J, Balaram P, Rivier JE, Olivera BM, Yoshikami D, Bulaj G, Norton RS. Mammalian Neuronal Sodium Channel Blocker μ‑Conotoxin BuIIIB Has a Structured N‑Terminus That Influences Potency. ACS Chemical Biology 2013, 8: 1344-1351. PMID: 23557677, PMCID: PMC4201638, DOI: 10.1021/cb300674x.Peer-Reviewed Original ResearchCyclic AMP-dependent Protein Lysine Acylation in Mycobacteria Regulates Fatty Acid and Propionate Metabolism*
Nambi S, Gupta K, Bhattacharyya M, Ramakrishnan P, Ravikumar V, Siddiqui N, Thomas AT, Visweswariah SS. Cyclic AMP-dependent Protein Lysine Acylation in Mycobacteria Regulates Fatty Acid and Propionate Metabolism*. Journal Of Biological Chemistry 2013, 288: 14114-14124. PMID: 23553634, PMCID: PMC3656268, DOI: 10.1074/jbc.m113.463992.Peer-Reviewed Original ResearchMeSH KeywordsAcetylesteraseAmino Acid SequenceBacterial ProteinsCoenzyme A LigasesCyclic AMPFatty AcidsGene DeletionGene Expression Regulation, BacterialLysineMass SpectrometryMolecular Sequence DataMutagenesisMycobacterium bovisMycobacterium tuberculosisPropionatesSequence Homology, Amino AcidSignal TransductionConceptsCAMP-dependent mannerAcyl-CoA synthetaseLysine residuesProtein Lysine AcylationLysine acetyltransferaseLysine acylationPosttranslational modificationsImportant lysine residuesFatty acidsBiological processesIntracellular cAMP levelsFADDMultiple substratesCoA synthetasePropionyl-CoAAcetylationBiological organismsRegulatory cycleCritical roleCAMP levelsResiduesBovis bacillus Calmette-GuérinPropionate metabolismMetabolismEukaryotes
2011
Combined Electron Transfer Dissociation–Collision-Induced Dissociation Fragmentation in the Mass Spectrometric Distinction of Leucine, Isoleucine, and Hydroxyproline Residues in Peptide Natural Products
Gupta K, Kumar M, Chandrashekara K, Krishnan KS, Balaram P. Combined Electron Transfer Dissociation–Collision-Induced Dissociation Fragmentation in the Mass Spectrometric Distinction of Leucine, Isoleucine, and Hydroxyproline Residues in Peptide Natural Products. Journal Of Proteome Research 2011, 11: 515-522. PMID: 22111579, DOI: 10.1021/pr200091v.Peer-Reviewed Original ResearchConceptsIsobaric residuesMass spectrometric peptide sequencingNatural peptide librariesPeptide natural productsCrude peptide mixturesTandem mass spectrometric methodMass spectrometric distinctionMass spectrometric methodRadical ionsIsobaric leucineElectron transferCollisional activationDissociation fragmentationPeptide mixturesNatural productsNominal massSpectrometric methodLiquid chromatographyPeptide sequencingPresence of hydroxyprolineIonsPeptide libraryDifferent peptidesDissociation approachHydroxyproline residues
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 ResearchConceptsS 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