FAICAR  (Synonyms: 5-Formamidoimidazole-4-carboxamide ribotide)

FAICAR (5-Formamidoimidazole-4-carboxamide ribotide) is a purine nucleotide and the IMP cyclohydrolase substrate of Cryptococcus neoformans ATIC. It is a key intermediate in the de novo purine synthesis pathway. FAICAR can be used in studies related to Cryptococcus neoformans infection^[1][2][3].

FAICAR (0.005-0.3 mM) was used as substrate at 37°C, and recombinantly expressed C. neoformans ATIC exhibits IMP cyclohydrolase activity with a K_m_app of 30 μM, Vmax of 8.6 U/mg, and kcat of 7.7 s^−1[1].
FAICAR (0.1-4 μM) acts as a substrate for human AICAR transformylase-IMP cyclohydrolase's IMP cyclohydrolase domain, with a K_s of 0.87 μM at pH 7.4, and supports an IMP cyclohydrolase specific activity of 29.5 nmol IMP formed/min/μg protein at a concentration of 4 μM^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

366.22

C₁₀H₁₅N₄O₉P

13018-54-7

Solid

Dark purple to black

O=C(C1=C(NC=O)N([C@@H]2O[C@H](COP(O)(O)=O)[C@@H](O)[C@H]2O)C=N1)N

Room temperature in continental US; may vary elsewhere.

-20°C, stored under nitrogen

*In solvent : -80°C, 6 months; -20°C, 1 month (stored under nitrogen)

• [1]. Wizrah MSI, et al. AICAR transformylase/IMP cyclohydrolase (ATIC) is essential for de novo purine biosynthesis and infection by Cryptococcus neoformans. J Biol Chem. 2022;298(10):102453.  [Content Brief]

  [2]. Szabados E, et al. Radioassay of bifunctional 5-aminoimidazole-4-carboxamide ribotide transformylase-IMP cyclohydrolase by thin-layer chromatography. Anal Biochem. 1994;221(2):401-404.  [Content Brief]

  [3]. Vergis JM, et al. Catalytic mechanism of the cyclohydrolase activity of human aminoimidazole carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase. Biochemistry. 2004;43(5):1184-1192.  [Content Brief]