Crystal structure of West Nile virus envelope glycoprotein visualized with Yasara . (A) Analyzed motifs on PDB:2hg0  highlighted in red (PAAP) or magenta (YCYL). Structural analysis suggests that the PAAP motif is surface accessible while the YCYL motif is buried. (B) Analysis of the envelope protein in context of the assembled viral envelope PDB:3iyw . Three envelope proteins are shown in gray, purple and yellow. The PAAP surface motif (red residues in black circles) appears to form part of the interface between the envelope subunits. It also lies adjacent to the discontinuous epitope recognition site of co-crystallized neutralizing antibodies (blue and green).
Garg et al. BMC Microbiology 2013 13:197 doi:10.1186/1471-2180-13-197