2.6.1.16	malfunction	deletion of the isozyme is lethal	759211	
2.6.1.16	metabolism	glutamine: fructose-6-phosphate amidotransferase (GFAT) enzymes catalyse the first committed step of the hexosamine biosynthesis pathway (HBP) using glutamine and fructose-6-phosphate to form glucosamine-6-phosphate (GlcN6P)	759211	
2.6.1.16	additional information	mutation of residue Ser593 enhances the flexibility of the protein, which ultimately leads to increased enzyme activity, molecular dynamics simulation, homology modeling, and protein-ligand docking, overview	-, 758961	
2.6.1.16	additional information	the glutaminase domain catalyzes the conversion of glutamine to glutamic acid with the release of ammonia. A catalytically important cysteinyl (Cys1) has been suggested to act as the mechanistic nucleophile after being activated by the N-terminal amine of the glutaminase domain (i.e. its own alpha-amine). Using molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) computational methods, the active site of the glutaminase domain, the protonation state of its N-terminal amine, substrate binding, and catalytic mechanism are analysed, potential for an active site histidyl (His71) to alternatively act as the required base. A tetrahedral oxyanion intermediate is formed during the mechanism, stabilized by a water and two enzyme residues: Asn98 and Gly99. The overall rate-limiting step of the mechanism is the nucleophilic attack of a water on the thioester cross-linked intermediate with a barrier of 74.4 kJ/mol. An alternate mechanism in which His71 acts as the nucleophile-activating base, and which requires the Cys1 alpha-amine to be protonated, is calculated to be enzymatically feasible but to have a much higher overall rate-limiting barrier of 93.7 kJ/mol. Structure-function analysis and enzyme-substrate binding, overview	760122	
2.6.1.16	additional information	the residues involved in substrate binding are conserved in both Drosophila melanogaster GFAT1 and GFAT2 isozymes	759211	
2.6.1.16	physiological function	a GlmS deletion mutant is defective in growth unless media are supplemented with D-glucosamine. The mutant is highly sensitive to detergents, hydrophobic antibiotics, and bile salts compared to the wild-type. Mutant secretes higher amounts of beta-lactamase than the wild-type in culture supernatant fractions and is attenuated in cell culture models of Salmonella infection	-, 737569	
2.6.1.16	physiological function	glucosamine-6-phosphate N-acetyltransferase (GNA1), catalyzing acetyl transfer from acetyl-coenzyme A to glucosamine-6-phosphate (GlcN-6P) and glutamine-fructose-6-phosphate aminotransferase (GlmS) catalyzing the formation of GlcN-6P from fructose-6-phosphate (Fru-6P), are two key enzymes in Bacillus subtilis for the bioproduction of N-acetylglucosamine (GlcNAc)	-, 756261	
2.6.1.16	physiological function	glucosamine-6-phosphate synthase (GlmS) is a key enzyme in the biosynthesis of hexosamine	760122	
2.6.1.16	physiological function	glucosamine-6-phosphate synthase is an important enzyme for bacterial and fungal cell wall synthesis	-, 758967	
2.6.1.16	physiological function	glutamine:fructose-6-phosphate amidotransferase is a rate-limiting enzyme in the hexoamine biosynthetic pathway and plays an important role in type 2 diabetes	703705