2.4.1.182 additional information involved in the biosynthetic pathway leading to 3-aminoglucosamine analogues of lipid A, responsible for cytotoxic effect on the host Acanthamoeba castellanii Legionella pneumophila ? - ? 89 2.4.1.182 additional information formation of lipid A disaccharide from UDP-GlcNAc and lipid X, i.e. 2,3-diacylglucosamine 1-phosphate, releasing UDP. Lipid X, i.e. 2,3-diacylglucosamine 1-phosphate, bears two R-3-hydroxymyristoyl chains in Arabidopsis thaliana and is a key precursor of lipid A. No other lipid X molecular species are detected Arabidopsis thaliana ? - ? 89 2.4.1.182 additional information LpxB combines lipid X with the preceding lipid metabolite, UDP-2,3-bis(beta-hydroxymyristoyl)-D-glucosamine, to form lipid A disaccharide Escherichia coli ? - ? 89 2.4.1.182 additional information LpxB only consumes lipid X in a 1:1 ratio with UDP-2,3-bis(beta-hydroxymyristoyl)-D-glucosamine. Near irreversibility of the LpxB enzyme Escherichia coli ? - ? 89 2.4.1.182 additional information analysis of UDP binding site structure and ligand-bound structure of LpxB. The GlcNAc moiety is highly flexible or that UDP-GlcNAc is hydrolysed during soaking. The uracil base binds in a hydrophobic pocket formed by L197, P198, P231, and V233, which is on the second Rossmann-fold domain and facing the deep inter-domain cleft. The P231 carbonyl oxygen also hydrogen-bonds with N3 of uracil and the G199 amide nitrogen hydrogen-bonds with the O4 carbonyl of uracil. In addition, two water molecules connect active site residues to uracil: the first water connects the G199 carbonyl oxygen and the V233 amide nitrogen to O4 of uracil, and the second water connects the G261 amide nitrogen to the O2 carbonyl of uracil Escherichia coli ? - - 89 2.4.1.182 additional information formation of lipid A disaccharide from UDP-GlcNAc and lipid X, i.e. 2,3-diacylglucosamine 1-phosphate, releasing UDP. Lipid X, i.e. 2,3-diacylglucosamine 1-phosphate, bears two R-3-hydroxymyristoyl chains in Arabidopsis thaliana and is a key precursor of lipid A. No other lipid X molecular species are detected Arabidopsis thaliana Col-0 ? - ? 89 2.4.1.182 UDP-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosamine + 2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate - Escherichia coli UDP + 2,3-bis((R)-3-hydroxytetradecanoyl)-beta-D-glucosaminyl-(1->6)-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate - ? 355101 2.4.1.182 UDP-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosamine + 2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate - Escherichia coli UDP + 2,3-bis((R)-3-hydroxytetradecanoyl)-beta-D-glucosaminyl-(1->6)-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate - ir 355101 2.4.1.182 UDP-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosamine + 2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate - Escherichia coli UDP + 2,3-bis((R)-3-hydroxytetradecanoyl)-beta-D-glucosaminyl-(1->6)-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate product analysis ? 355101 2.4.1.182 UDP-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosamine + 2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate 2,3-diacylglucosamine 1-phosphate is lipid X Escherichia coli UDP + 2,3-bis((R)-3-hydroxytetradecanoyl)-beta-D-glucosaminyl-(1->6)-2,3-bis((R)-3-hydroxytetradecanoyl)-alpha-D-glucosaminyl 1-phosphate - ? 355101