Current Progress in the Structural and Biochemical Characterization of Proteins Involved in the Assembly of Lipopolysaccharide

Figure 3

LpxA: (a) ribbon diagram of the LpxA trimer bound to its UDP-3-O-(R3-hydroxymyristoyl)-N-acetylglucosamine product (PDB: 2QIA) [23]; (b) residues involved in product binding from (a). Subscripts are used below to distinguish subunits in the trimer. Hydrogen-bonding interactions are shown. Distances of interactions in Ångstroms are as follows: 3.3 from 3′-acyl carbonyl O to G143_0.3 N 3.2 from uracil O4 to N198_0.1 Nδ, 3.0 from uracil O4 to R205_0.1 Nη2 2.7 from uracil N3 to N198_0.1 Oδ, 2.9 from water to H99_0.3 Nδ, 2.8 from same water to β-hydroxyl, 2.8 from β-hydroxyl to H122_0.3 Nε, 3.0 from β-hydroxyl to Q73_0.3 Nε, 3.3 from glucosamine 3′O to H125_0.3, 2.8 from H125_0.3 Nδ to D126_0.3, 2.9 from glucosamine 6′-hydroxyl to H144_0.3 Nε, 3.0 from the glucosamine ring O to K76_0.3 Nζ, 3.0 from 2′-acetyl carbonyl to L75_0.3 N, and 2.6 from α-phosphate to Q161_0.3 Nε. Protein structure figures were generated using UCSF Chimera [24].