Non-homologous isofunctional enzymes

Non-Homologous Isofunctional Enzymes (NISE) are two evolutionarily unrelated enzymes that catalyze the same chemical reaction. Enzymes that catalyze the same reaction are sometimes referred to as analogous as opposed to homologous (Homology (biology)), however it is more appropriate to name them as Non-homologous Isofunctional Enzymes, hence the acronym (NISE).^[1] These enzymes all serve the same end function but do so in different organisms without detectable similarity in primary and possibly tertiary structures.^[2]