FAD-AMP lyase (cyclizing)

In enzymology, a FAD-AMP lyase (cyclizing) () is an enzyme that catalyzes the chemical reaction
Hence, this enzyme has one substrate, FAD, and two products, AMP and riboflavin cyclic-4',5'-phosphate.
This enzyme belongs to the family of lyases, specifically the class of phosphorus-oxygen lyases. The systematic name of this enzyme class is FAD AMP-lyase (riboflavin-cyclic-4',5'-phosphate-forming). Other names in common use include FMN cyclase, and FAD AMP-lyase (cyclic-FMN-forming).