NO biosynthesis Authored: Hemish, J, 2007-10-19 18:00:42 EC Number: 1.14.13.39 Nitric oxide (NO) is produced from L-arginine by the family of nitric oxide synthases (NOS) enzymes, forming the free radical NO and citrulline as byproduct. The cofactor tetrahydrobiopterin (BH4) is an essential requirement for the delivery of an electron to the intermediate in the catalytic cycle of NOS. Pubmed15467163 Pubmed7526779 Pubmed8782602 Pubmed9173876 Reactome Database ID Release 43202127 Reactome, http://www.reactome.org ReactomeREACT_12443 Reviewed: Enikolopov, G, 2008-02-28 17:52:44 has a Stoichiometric coefficient of 2