CatalysisEnzymesBiocatalysisCatalytic DomainKineticsModels, MolecularProtein ConformationModels, ChemicalBinding SitesHydrogen-Ion ConcentrationSubstrate SpecificityCrystallography, X-RayMolecular Sequence DataMutagenesis, Site-DirectedAmino Acid SequenceEscherichia coliRNA, CatalyticHydrolysisProtein Structure, TertiaryProtein BindingHistidineMolecular StructureMutationStructure-Activity RelationshipRecombinant ProteinsBase SequenceSequence Homology, Amino AcidOxidation-ReductionAntibodies, CatalyticStereoisomerismHydrogen BondingAmino Acid SubstitutionEnzyme StabilityAspartic AcidSequence AlignmentProtein Structure, SecondaryMetalsThermodynamicsMagnesiumMolecular ConformationCysteineBacterial ProteinsProtonsConserved SequenceCloning, Molecular