IUBMB Enzyme Nomenclature


Accepted name: phosphoribosyl-AMP cyclohydrolase

Reaction: 1-(5-phospho-β-D-ribosyl)-AMP + H2O = 1-(5-phospho-β-D-ribosyl)-5-[(5-phospho-β-D-ribosylamino)methylideneamino]imidazole-4-carboxamide

For diagram click here.

Other name(s): PRAMP-cyclohydrolase; phosphoribosyladenosine monophosphate cyclohydrolase; 1-(5-phospho-D-ribosyl)-AMP 1,6-hydrolase

Systematic name: 1-(5-phospho-β-D-ribosyl)-AMP 1,6-hydrolase

Comments: The Neurospora crassa enzyme also catalyses the reactions of EC (histidinol dehydrogenase) and EC (phosphoribosyl-ATP diphosphatase).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37289-22-8


1. Minson, A.C. and Creaser, E.H. Purification of a trifunctional enzyme, catalysing three steps of the histidine pathway, from Neurospora crassa. Biochem. J. 114 (1969) 49-56. [PMID: 4309307]

[EC created 1972, modified 1976, modified 1981, modified 2000]

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