Formation of glucosamine 6-phosphate from fructose 6-phosphate and glutamine Authored: Dall'Olio, GM, 2009-11-10 EC Number: 2.6.1.16 Edited: Jassal, B, 2009-12-07 Glucosamine-fructose 6-phosphate aminotransferase (GFAT) is the first and rate-limiting enzyme in the hexosamine synthesis pathway, and thus formation of hexosamines like N-acetylglucosamine (GlcNAc). This enzyme probably plays a role in limiting the availability of substrates for the N- and O- linked glycosylation of proteins. Two isoforms, GFAT 1 and 2, have been identified (McKnight GL et al, 1992; Oki T et al, 1999). GFAT is required normal functioning of neuromuscular synaptic transmission. Defects in the gene expressing this protein leads to altered muscle fiber morphology and impaired neuromuscular junction development (Senderek et al, 2011). Pubmed10198162 Pubmed1460020 Pubmed21310273 Reactome Database ID Release 43449715 Reactome, http://www.reactome.org ReactomeREACT_22115 Reviewed: Gagneux, P, 2010-04-16