Isozymes(alsoknownasisoenzymes)areenzymesthatdifferinaminoacidsequencebutcatalyzethesamechemicalreaction.Theseenzymesusuallydisplaydifferentkineticparameters(i.e.differentKMvalues),ordifferentregulatoryproperties.Theexistenceofisozymespermitsthefine-tuningofmetabolismtomeettheparticularneedsofagiventissueordevelopmentalstage(forexamplelactatedehydrogenase(LDH)).Inbiochemistry,isozymes(orisoenzymes)areisoforms(closelyrelatedvariants)ofenzymes.Inmanycases,theyarecodedforbyhomologousgenesthathavedivergedovertime.Although,strictlyspeaking,allozymesrepresentenzymesfromdifferentallelesofthesamegene,andisozymesrepresentenzymesfromdifferentgenesthatprocessorcatalysethesamereaction,thetwowordsareusuallyusedinterchangeably.