Table 1.
Energy parameters for the model complexes UDP-GlcUA/K4CP, UDP-GlcUA/(R313Q)-K4CP, UDP-GalNAc/K4CP and UDP-GalNAc/(R313Q)-K4CP.
| Complex | Conf. of Arg268a | Energy (kcal/mol) | ||||||
|---|---|---|---|---|---|---|---|---|
| LPEb | LEb | ΔEc | R268d | X313d | D311d | S334d | ||
| K4CP/UDP-GlcUAe | ext.a | -102.8 | -64.1 | -5.4 | -12.7 | -2.5 | 2.2 | -0.8 |
| benta | -99.3 | -64.0 | -8.7 | -2.5 | 2.0 | -2.0 | ||
| (R313Q)/UDP-GlcUAe | ext. | -100.6 | -63.8 | +1.3 | -12.6 | 0.14 | 2.0 | -1.4 |
| bent | -96.5 | -63.9 | -8.0 | 0.21 | 1.8 | -1.9 | ||
| K4CP/UDP-GalNAc (R313Q)/UDP-GalNAc | bent | -100.6 | -71.5 | n.a.f | -4.3 | -0.64 | 0.55 | -0.72 |
| bent | -99.4 | -71.5 | n.a.f | -3.7 | ~0 | 0.59 | -0.72 | |
a Conformation of Arg-268: extended (ext.), χ1 = 61°, χ2 = -165°, χ3 = 176°, χ4 = -163°; bent, χ1 = 55°, χ2 = 175°, χ3 = 168°, χ4 = -86°.
b LPE and LE are, respectively, the ligand/protein interaction energy and the ligand internal energy (including torsional energy and van der Waals and electrostatic interactions among ligand atoms).
c Difference between the total energy of the complex with Arg-268 in the extended conformation and the total energy of the complex with Arg-268 in the bent conformation.
d Contributions of single residues to LPE.
e The energy parameters of the most stable form of each complex are shown in bold.
f n.a., not applicable.