allantoinase

{{Short description|Enzyme in the InterPro Family}}

{{infobox enzyme

| Name = allantoinase

| EC_number = 3.5.2.5

| CAS_number = 9025-20-1

| GO_code = 0004038

| image = 3cl7.jpg

| width = 270

| caption = Allantoinase (analog) tetramer, Pseudomonas fluorescens

}}

In enzymology, an allantoinase ({{EC number|3.5.2.5}}) is an enzyme that catalyzes the chemical reaction

:(S)-allantoin + H₂O $\backslash rightleftharpoons$ allantoate

Thus, the two substrates of this enzyme are (S)-allantoin and H₂O, whereas its product is allantoate.

This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in cyclic amides. The systematic name of this enzyme class is (S)-allantoin amidohydrolase. This enzyme participates in purine metabolism.