2015
Chapter Nine Biophysical Approaches to the Study of LeuT, a Prokaryotic Homolog of Neurotransmitter Sodium Symporters
Singh SK, Pal A. Chapter Nine Biophysical Approaches to the Study of LeuT, a Prokaryotic Homolog of Neurotransmitter Sodium Symporters. Methods In Enzymology 2015, 557: 167-198. PMID: 25950965, PMCID: PMC4818570, DOI: 10.1016/bs.mie.2015.01.002.Peer-Reviewed Original ResearchConceptsMultiple integral membrane proteinsSolute carrier 6 (SLC6) familyNeurotransmitter sodium symportersIntegral membrane proteinsAmino acid symporterDependent neurotransmitter transportersEukaryotic counterpartsSodium symportersProkaryotic homologAcid symporterLeuT structureMembrane proteinsNeurotransmitter transportersBiophysical approachesLeuTHomology modelingMechanism of transportSecondary transportAmino acidsLipid bilayersSignificant transportersMechanistic paradigmMolecular dynamics simulationsSymporterProtein
2014
Functionally Important Carboxyls in a Bacterial Homologue of the Vesicular Monoamine Transporter (VMAT)*
Yaffe D, Vergara-Jaque A, Shuster Y, Listov D, Meena S, Singh SK, Forrest LR, Schuldiner S. Functionally Important Carboxyls in a Bacterial Homologue of the Vesicular Monoamine Transporter (VMAT)*. Journal Of Biological Chemistry 2014, 289: 34229-34240. PMID: 25336661, PMCID: PMC4256354, DOI: 10.1074/jbc.m114.607366.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsArginineBacterial ProteinsBiogenic MonoaminesBrevibacillusCarrier ProteinsDrug Resistance, BacterialEscherichia coliEvolution, MolecularGene ExpressionHistidineModels, MolecularMolecular Sequence DataProtein FoldingRatsRecombinant ProteinsSequence AlignmentStructural Homology, ProteinStructure-Activity RelationshipSubstrate SpecificitySynaptic TransmissionVesicular Monoamine Transport ProteinsConceptsBacterial multidrug transportersMultidrug transporterBacterial homologueVesicular monoamine transporterRat vesicular monoamine transporterMonoamine transportersPreliminary biochemical characterizationMammalian transportersTransmembrane helicesMammalian counterpartsTransmembrane segmentsMammalian organismsEvolutionary aspectsMajor facilitatorBiochemical characterizationImportant carboxylB. brevisHomology modelBiochemical studiesTransportersHomologuesCarboxyl residuesAntibiotic resistanceOrganismsNeurotransporters
2013
Radioligand Binding to Nanodisc-Reconstituted Membrane Transporters Assessed by the Scintillation Proximity Assay
Nasr ML, Singh SK. Radioligand Binding to Nanodisc-Reconstituted Membrane Transporters Assessed by the Scintillation Proximity Assay. Biochemistry 2013, 53: 4-6. PMID: 24344975, PMCID: PMC4062192, DOI: 10.1021/bi401412e.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid Transport Systems, NeutralBacterial ProteinsLigandsLipid BilayersNanostructuresScintillation CountingConceptsMembrane transportersPhospholipid bilayer nanodiscsNative cell membranesSecondary transportersScintillation proximityBilayer nanodiscsDetergent solubilizationCell membraneLipid vesiclesTransportersNanodiscsScreening effortsBackground interferenceLeuTProteinVesiclesPowerful techniqueBindingMembraneReconstitutionRadioligand bindingSolubilizationInterferencePotential challengesProximity
2008
A Competitive Inhibitor Traps LeuT in an Open-to-Out Conformation
Singh SK, Piscitelli CL, Yamashita A, Gouaux E. A Competitive Inhibitor Traps LeuT in an Open-to-Out Conformation. Science 2008, 322: 1655-1661. PMID: 19074341, PMCID: PMC2832577, DOI: 10.1126/science.1166777.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid Transport SystemsAmino AcidsBacterial ProteinsBinding SitesBinding, CompetitiveBiological TransportCrystallizationCrystallography, X-RayHydrogen BondingHydrophobic and Hydrophilic InteractionsKineticsLeucineLigandsModels, BiologicalModels, MolecularProtein ConformationProtein Structure, TertiarySodiumSymportersTryptophanConceptsNeurotransmitter sodium symportersPrimary substrate siteAmino acid substratesSodium symportersSecondary transportersExtracellular gateSubstrate passageLeucine transporterArginine 30Substrate transportCellular membranesConformational changesAcid substratesConformational statesSubstrate siteFunctional studiesIon gradientsLeuTWeak binding sitesTransportersBinding sitesSmall moleculesCompetitive inhibitorConformationTrp complexLeuT: A prokaryotic stepping stone on the way to a eukaryotic neurotransmitter transporter structure
Singh SK. LeuT: A prokaryotic stepping stone on the way to a eukaryotic neurotransmitter transporter structure. Channels 2008, 2: 380-389. PMID: 19066470, DOI: 10.4161/chan.2.5.6904.Peer-Reviewed Original ResearchMeSH KeywordsBacterial ProteinsEukaryotaHumansPlasma Membrane Neurotransmitter Transport ProteinsProtein ConformationConceptsSodium binding siteSolute carrier 6 (SLC6) familyIntegral membrane proteinsStructure/function studiesBinding sitesCrystal structureEukaryotic counterpartsAccurate homology modelsTransporter structureBacterial membersMembrane proteinsNutrient uptakeSequence identityMolecular insightsConformational changesHomology modelSecondary transportLeuTNeurotransmitter clearanceLipid bilayersSolute moleculesBiochemical dataFunction studiesIon bindingCrucial role
2005
Crystal structure of a bacterial homologue of Na+/Cl--dependent neurotransmitter transporters
Yamashita A, Singh SK, Kawate T, Jin Y, Gouaux E. Crystal structure of a bacterial homologue of Na+/Cl--dependent neurotransmitter transporters. Nature 2005, 437: 215-223. PMID: 16041361, DOI: 10.1038/nature03978.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceBacteriaBacterial ProteinsBinding SitesBiological TransportChloridesCrystallography, X-RayHydrophobic and Hydrophilic InteractionsLeucineMembrane Transport ProteinsModels, MolecularMolecular Sequence DataNeurotransmitter AgentsSequence AlignmentSodiumStructure-Activity RelationshipWaterConceptsBacterial homologueProtein coreDependent neurotransmitter transportersTransmembrane helicesTransmembrane segmentsAquifex aeolicusUptake of neurotransmittersSubstrate bindingNeurotransmitter transportersMain-chain atomsMembrane bilayerDependent transportersElectrochemical gradientIon binding siteTransportersHelix dipole