A Micropolymorphism Altering the Residue Triad 97/114/156 Determines the Relative Levels of Tapasin Independence and Distinct Peptide Profiles for HLA-A24 Allotypes

Figure 8

Representation of the 97/114/156 residue triad. Ribbon representation of the HLA-A24:02 structure (PDB 3I6L) [29], HLA hc (green) and b2m (turquoise) and peptide (yellow); residues 97, 99, 114, 133, and 156 are drawn as ball and stick (a). A magnified view of the residues highlighted in (a); the HLA hc, b2m, and peptide have been removed for clarity (b). The residue triad Met97/His114/Gln156 from the HLA-A24:02 structure is shown as ball and stick with a transparent van der Waals surface (grey). The HLA-A24: (pink) or HLA-A24: (orange) polymorphisms, depicted as a dotted van der Waals surface, show increased energetically stability provided by improved packing between the triad residues and aromatic residues Phe99 and Trp133.

(a)

(b)