IUBMB Enzyme Nomenclature


Accepted name: GTP cyclohydrolase II

Reaction: GTP + 3 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate

Other name(s): guanosine triphosphate cyclohydrolase II; GTP-8-formylhydrolase

Systematic name: GTP 7,8-8,9-dihydrolase (diphosphate-forming)

Comments: Two C-N bonds are hydrolysed, releasing formate, with simultaneous removal of the terminal diphosphate.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 56214-35-8


1. Foor, F. and Brown, G.M. Purification and properties of guanosine triphosphate cyclohydrolase II from Escherichia coli. J. Biol. Chem. 250 (1975) 3545-3551. [PMID: 235552]

[EC created 1984, modified 2011]

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