PathwayStep2241 PathwayStep2228 PathwayStep2216 Purine salvage Purine ribonucleoside monophosphate biosynthesis Purine catabolism Purine metabolism Authored: Jassal, B, 2003-06-26 04:06:16 Edited: D'Eustachio, P, 0000-00-00 00:00:00 GENE ONTOLOGYGO:0006144 Pubmed4620886 Reactome Database ID Release 4373847 Reactome, http://www.reactome.org ReactomeREACT_522 Reviewed: Rush, MG, 2008-01-11 00:00:00 The events of human purine metabolism are conveniently, if somewhat arbitrarily, grouped into four pathways: de novo synthesis of inosine 5'-monophosphate (IMP), the biosynthesis of other purine ribo- and deoxyribonucleotides, purine salvage reactions, and purine catabolism (Watts 1974).<P><B>De novo synthesis of inosine 5'-monophosphate (IMP).</B> The purine ribonucleotide IMP is assembled on 5-phospho-alpha-D-ribose 1-diphosphate (PRPP).<P><B>Purine biosynthesis [interconversion].</B> Purine ribo- and deoxyribonucleotide di- and triphosphates are synthesized, both from IMP and from guanosine and adenosine ribo- and deoxyribonucleotide monophosphates generated in salvage reactions. <P><B>Purine salvage reactions.</B> Purine nucleosides and free bases generated by DNA and RNA breakdown are converted to nucleotide monophosphates.<P><B>Purine catabolism.</B> The purine bases guanine and hypoxanthine are degraded to uric acid, which is excreted from the body.