2.4.1.182 evolution LpxB is among the most highly conserved enzymes in the Raetz pathway 759836 2.4.1.182 evolution LpxB is an inverting glycosyltransferase of family 19 of the GT-B superfamily -, 758842 2.4.1.182 malfunction 42fold accumulation of 2,3-diacylglucosamine 1-phosphate in Arabidopsis thaliana atlpxb-1 mutant -, 718879 2.4.1.182 malfunction overexpression of LpxB in Escherichia coli results in the accumulation of aberrant tubular membranes of a uniform diameter along the inner surface of the bacterial inner membrane, suggesting that the accumulation of the lipid product of the LpxB reaction, 2',3'-diacylglucosamine-(beta,1'-6)-2,3-diacylglucosamine-1-phosphate (DSMP), is toxic to cells -, 758842 2.4.1.182 metabolism catalyzes the fifth step of lipid A biosynthesis -, 702266 2.4.1.182 metabolism LpxB is a glycosyltransferase in the Raetz (lipid A synthesis) pathway that catalyzes nucleophilic attack of the 6'-hydroxyl of lipid X on the anomeric carbon of UDP-diacyl-glucosamine (UDP-DAG) to form beta(1-6)-tetraacyl-disaccharide 1-phosphate (lipid A disaccharide) 759836 2.4.1.182 metabolism the enzyme is involved in the lipid A biosynthesis catalyzing the fifth step, LpxH and LpxB may form a complex that performs metabolic channeling. LpxB combines lipid X with the preceding lipid metabolite, UDP-2,3-bis(beta-hydroxymyristoyl)-D-glucosamine, to form lipid A disaccharide. Development of a quantitative model of the nine enzyme-catalyzed steps of Escherichia coli lipid A biosynthesis, modelling, detailed overview 737072 2.4.1.182 additional information Escherichia coli enzyme LpxB has a glycosyltransferase-B family fold but with a highly intertwined, C-terminally swapped dimer comprising four domains. Homology modeling using the UDP-N-acetylglucosamine 2-epimerase structure from Thermus thermophilus strain HB8 (PDB ID 1V4V) as template, structure comparisons, overview. The hydrophobic patch (V66, V68, L69, L72, L75, and L76) is essential for productive membrane association or substrate binding 759836 2.4.1.182 physiological function most Gram-negative bacteria are surrounded by a glycolipid called lipopolysaccharide (LPS), which forms a barrier to hydrophobic toxins and, in pathogenic bacteria, is a virulence factor. During LPS biosynthesis, the membrane-associated glycosyltransferase (LpxB) forms a tetraacylated disaccharide that is further acylated to form the membrane anchor moiety of LPS. LpxB is essential for growth of Escherichia coli and is among the most highly conserved enzymes in the Raetz pathway 759836 2.4.1.182 physiological function role of LpxB as the disaccharide synthetase to condense UDP-DAGn with lipid X to form DSMP and UDP -, 758842