Xylono 1,4 lactonase

In enzymology, a xylono-1,4-lactonase (EC 3.1.1.68) is an enzyme that catalyzes the chemical reaction

Thus, the two substrates of this enzyme are D-xylono-1,4-lactone and H₂O, whereas its product is D-xylonate.

This enzyme belongs to the family of hydrolases, specifically those acting on carboxylic ester bonds. The systematic name of this enzyme class is D-xylono-1,4-lactone lactonohydrolase. Other names in common use include xylono-g-lactonase, and xylonolactonase. This enzyme participates in pentose and glucuronate interconversions.