Glutamine Fructose-6-Phosphate Transaminase 2 (GFPT2)

Glutamine:fructose-6-phosphate amidotransferase (GFAT) is the first and rate-limiting enzyme of the hexosamine biosynthesis pathway. The enzyme transfers the amide group from L-glutamine to fructose 6-phosphate to form glucosamine 6-phosphate. See GFAT1 (GFPT1). By searching an EST database for sequences related to GFAT1, Oki et al. (1999) identified a cDNA encoding a new GFAT subtype that they called GFAT2. The predicted 682-amino acid human protein shares 76% and 97% similarity to human GFAT1 and mouse Gfat2, respectively. Recombinant GFAT2 exhibited GFAT enzyme activity in vitro. Northern blot analysis revealed that GFAT2 was expressed predominantly as a 3-kb mRNA, although additional transcripts were present in some tissues. The highest levels of expression were observed in heart, placenta, and spinal cord.