Tags: Enzyme.
In enzymology a tetrahydroxypteridine cycloisomerase (EC 5.5.1.3) is an enzyme that catalyzes the chemical reactiontetrahydroxypteridine xanthine-8-carboxylateHence this enzyme has one substrate tetrahydroxypteridine and one product xanthine-8-carboxylate.This enzyme belongs to the family of isomerases specifically the class of intramolecular lyases. The systematic name of this enzyme class is tetrahydroxypteridine lyase (isomerizing). It employs one cofactor NAD+.