IUBMB Enzyme Nomenclature


Accepted name: formate—phosphoribosylaminoimidazolecarboxamide ligase

Reaction: ATP + formate + 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide = ADP + phosphate + 5-formamido-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide

Other name(s): 5-formaminoimidazole-4-carboxamide ribonucleotide synthetase; 5-formaminoimidazole-4-carboxamide-1-β-D-ribofuranosyl 5'-monophosphate synthetase; purP (gene name)

Systematic name: formate:5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide ligase (ADP-forming)

Comments: This archaeal enzyme, characterized from the methanogen Methanocaldococcus jannaschii, catalyses a step in the synthesis of purine nucleotides. It differs from the orthologous bacterial/eukaryotic enzymes, which utilize 10-formyltetrahydrofolate rather than formate and ATP. cf. EC, phosphoribosylaminoimidazolecarboxamide formyltransferase.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Ownby, K., Xu, H. and White, R.H. A Methanocaldococcus jannaschii archaeal signature gene encodes for a 5-formaminoimidazole-4-carboxamide-1-β-D-ribofuranosyl 5'-monophosphate synthetase. A new enzyme in purine biosynthesis. J. Biol. Chem. 280 (2005) 10881-10887. [PMID: 15623504]

2. Zhang, Y., White, R.H. and Ealick, S.E. Crystal structure and function of 5-formaminoimidazole-4-carboxamide ribonucleotide synthetase from Methanocaldococcus jannaschii. Biochemistry 47 (2008) 205-217. [PMID: 18069798]

[EC created 2013]

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