Formimidoyltetrahydrofolate cyclodeaminase
In enzymology, a formimidoyltetrahydrofolate cyclodeaminase (EC4.3.1.4) is an enzyme that catalyzes the chemical reaction
Hence, this enzyme has one substrate, 5-formimidoyltetrahydrofolate, and two products, 5,10-methenyltetrahydrofolate and NH3.
This enzyme belongs to the family of lyases, specifically ammonia lyases, which cleave carbon-nitrogen bonds. The systematic name of this enzyme class is 5-formimidoyltetrahydrofolate ammonia-lyase (cyclizing 5,10-methenyltetrahydrofolate-forming). Other names in common use include formiminotetrahydrofolate cyclodeaminase, and 5-formimidoyltetrahydrofolate ammonia-lyase (cyclizing). This enzyme participates in folate metabolism by catabolising histidine and adding to the C1-tetrahydrofolate pool.