CatalysisEnzymesBiocatalysisCatalytic DomainKineticsModels, MolecularProtein ConformationModels, ChemicalBinding SitesHydrogen-Ion ConcentrationSubstrate SpecificityCrystallography, X-RayMutagenesis, Site-DirectedMolecular Sequence DataAmino Acid SequenceEscherichia coliRNA, CatalyticHydrolysisHistidineMolecular StructureProtein Structure, TertiaryProtein BindingStructure-Activity RelationshipRecombinant ProteinsAntibodies, CatalyticOxidation-ReductionStereoisomerismSequence Homology, Amino AcidHydrogen BondingBase SequenceMutationAmino Acid SubstitutionEnzyme StabilityAspartic AcidMetalsProtein Structure, SecondaryThermodynamicsMagnesiumSequence AlignmentCysteine