Amino AcidsAmino Acid Transport SystemsReceptors, Purinergic P2X1LeucineSequence Homology, Amino AcidSerineAmino Acid SequenceAmino Acid SubstitutionCloning, MolecularAmino Acids, EssentialSequence AlignmentMolecular Sequence DataBase SequenceSerine EndopeptidasesMutationAmino Acid MotifsBinding SitesEscherichia coliMutagenesis, Site-DirectedKineticsDNA, ComplementaryRecombinant ProteinsPeptide FragmentsSequence Homology, Nucleic AcidProtein ConformationModels, MolecularSubstrate SpecificityAmino Acids, AromaticAmino Acids, Branched-ChainStructure-Activity RelationshipProtein Structure, TertiaryAmino Acids, SulfurProtein BindingMolecular WeightCell LinePeptidesDNABacterial ProteinsAlanineRestriction MappingElectrophoresis, Polyacrylamide GelPhylogenyRecombinant Fusion ProteinsProteinsSequence Analysis, DNASerine Proteinase InhibitorsRNA, MessengerGenes, BacterialSerine ProteasesProtein Structure, SecondaryPlasmidsChromatography, High Pressure LiquidAmino Acid Transport Systems, BasicConserved SequenceCarrier ProteinsSpecies SpecificityDNA PrimersLysineAmino Acids, NeutralTrypsinIsoleucineCattleGlycineBiological TransportCodonAmino Acids, BasicPhosphorylationHydrogen-Ion ConcentrationThreonineCyanogen BromideCysteineAspartic AcidGlutamineAmino Acids, DiaminoTransfectionMethionineGenesSaccharomyces cerevisiaeArginineOpen Reading FramesProtein BiosynthesisProlineValinePoint MutationPolymerase Chain ReactionSequence DeletionMutagenesisMembrane ProteinsGene LibraryPhenylalanineSequence AnalysisEndopeptidasesNitrogenTranscription, GeneticEvolution, MolecularNeutral RedExcitatory Amino AcidsHydrolysisTryptophanAmino Acid Transport System A