Figure 3.
Electrostatic potential at the surface of three alternative models for SIYRYYGL/H-2Kb (a–c, Left). The large picture on the right is a superposition of the backbone geometries. Positions of charged groups and conformations of the peptides of the three structures are displayed. The orientation is identical to the representation of the electrostatic potential, with the N terminus of the peptide pointing down. The backbones of the peptide conformations are displayed in bright colors, the backbones of the MHC conformations in dull colors (yellow/brown, pink/dark blue, cyan/green are used for the peptide MHC backbone corresponding to the representations a, b, and c, respectively). Charged groups of lysine and arginine are represented by blue, those of glutamic acid and aspartic acid by red spheres. Positive and negative electrostatic potentials are displayed in blue and red, respectively.