Amino AcidsSequence Homology, Amino AcidAmino Acid SequenceAmino Acid SubstitutionCloning, MolecularEscherichia coliBase SequenceAmino Acids, EssentialKineticsMutationMolecular Sequence DataProtein BiosynthesisAmino Acid Transport SystemsSequence AlignmentLeucineDNARNA, MessengerBinding SitesAmino Acid MotifsCell LineBacterial ProteinsStructure-Activity RelationshipRecombinant ProteinsMutagenesis, Site-DirectedDNA, ComplementaryModels, MolecularMolecular WeightSequence Homology, Nucleic AcidPeptide FragmentsAmino Acids, Branched-ChainStereoisomerismAmino Acids, AromaticSubstrate SpecificityProtein ConformationPeptidesProtein BindingElectrophoresis, Polyacrylamide GelAmino Acids, SulfurMolecular StructureProtein Structure, TertiaryTranscription, GeneticProteinsCells, CulturedGenes, BacterialPlasmidsRestriction MappingChromatography, High Pressure LiquidLiverRecombinant Fusion ProteinsProtein Synthesis InhibitorsMethionineAlanineCarbon IsotopesSequence Analysis, DNADNA PrimersPhylogenyCarrier ProteinsPhenylalanineCattleSpecies SpecificitySaccharomyces cerevisiaeGenesLysineBiological TransportViral ProteinsRNAIsoleucineArginineConserved SequenceGlutamineCycloheximideProtein Structure, SecondaryCatalysisTritiumGlycineDNA, BacterialAmino Acid Transport Systems, BasicCodonNitrogenValineDNA ReplicationTime FactorsMagnetic Resonance SpectroscopyRabbitsProlineTemperatureGene ExpressionMembrane ProteinsBlotting, NorthernTransfectionOpen Reading FramesPolymerase Chain ReactionTrypsinAmino Acids, BasicMutagenesisCricetinaeCulture MediaTryptophanSequence DeletionCysteine