Cyclisation of GTP to precursor Z NFS1 transfers sulfur from cysteine onto MOCS3 PathwayStep2400 PathwayStep2397 PathwayStep2398 PathwayStep2395 PathwayStep2396 PathwayStep2399 Molybdenum cofactor biosynthesis Authored: Stephan, R, 2010-09-05 Edited: Jassal, B, 2010-09-08 GENE ONTOLOGYGO:0032324 Molybdenum cofactor (MoCo) is needed by three enzymes in humans: sulfite oxidase, xanthine oxidase and aldehyde oxidase. The pathway of its synthesis is so conserved that plants and bacteria can readily use human enzymes. Bacteria, however, diverge after the first three steps from this path and their final MoCo differs from that of the eukaryotes. Plants and animals have also developed a refinement of their MoCo which is needed for the function of their xanthine and aldehyde oxidases. This means, in humans we find sulfurated instead of desulfurated molybdenum cofactor on these two enzymes (Schwarz 2005; Schwarz, Mendel, Ribbe 2009). Pubmed16261263 Pubmed19675644 Reactome Database ID Release 43947581 Reactome, http://www.reactome.org ReactomeREACT_25073 Reviewed: D'Eustachio, P, 2010-11-05 Transfer of sulfur from MOCS3-S-S onto MOCS2A Sulfhydrylation and ring cleavage of precursor Z Molybdenum ion transfer onto molybdopterin Exchange of oxygen with sulfur in MoCo