6-Formylpterin

6-Formylpterin is an oxidized pterin produced by photolytic breakdown of folic acid.¹ It binds to one of two active sites on XO nearly quantitatively and irreversibly and prevents the metabolism of other substrates at the second site, resulting in “hetero-substrate” inhibition at nanomolar concentrations.^1,2 However, 6-formylpterin itself is converted by XO to 6-carboxylpterin and H₂O₂ and the turnover rate of this reaction can actually be accelerated by prior binding of a hetero-substrate to XO.² In this way, 6-formylpterin acts as an intracellular generator of H₂O₂ in cells expressing XO, altering cellular function.^3,4

WARNING This product is not for human or veterinary use.

1. Spector, T., and Ferone, R. Folic acid does not inactivate xanthine oxidase. The Journal of Biological Chemisty 259(17), 10784-10786 (1984).

2. Tai, L.A., and Hwang, K.C. Regulation of xanthine oxidase activity by substrates at active sites via cooperative interactions between catalytic subunits: Implication to drug pharmacokinetics. Curr. Med. Chem. 18(1), 69-78 (2011).

3. Yamashita, K., Arai, T., Fukuda, K., et al. 6-Formylpterin intracellularly generates hydrogen peroxide and restores the impaired bactericidal activity of human neutrophils. Biochem. Biophys. Res. Commun. 289(1), 85-90 (2001).

4. Mori, H., Arai, T., Hirota, K., et al. Effects of 6-formylpterin, a xanthine oxidase inhibitor and a superoxide scavenger, on production of nitric oxide in RAW 264.7 macrophages. Biochim. Biophys. Acta 1474(1), 93-99 (2000).