In enzymology, a 1,4-lactonase (EC 18.104.22.168) is an enzyme that catalyzes the generic chemical reaction:a 1,4-lactone + H2O
Thus, the two substrates of this enzyme are 1,4-lactone and H2O, whereas its product is 4-hydroxyacid.
This enzyme belongs to the family of hydrolases, specifically those acting on carboxylic ester bonds. The systematic name of this enzyme class is 1,4-lactone hydroxyacylhydrolase. This enzyme is also called gamma-lactonase. This enzyme participates in galactose metabolism and ascorbate and aldarate metabolism. It employs one cofactor, calcium.
As of late 2007, three structures have been solved for this class of enzymes, with PDB accession codes 2DG0, 2DG1, and 2DSO.