Figure 1.
HA180-195 epitope homology among different influenza virus heterotypes. (A) Sequence alignment of the HA proteins from several influenza virus strains and homologous residues 180–195 comprising part of the Sb antigenic site. (B) Ribbon representation of the HA protein (PDB ID 1ru7:A, residues 54–270) revealing the Sb antigenic site in red. Shown is in detailed view of the Sb antigenic site, the 180–195 residues side chains in ball and stick representation together with their carbon atoms colored in grey, nitrogen in blue and oxygen in red. The first and last residues of the Sb site are indicated with a black dot and labeled, and the highly exposed residues of the HA180-195 epitope located within the a-helix are labeled. (C) Overlapped conformations of soluble HA180-195 epitope from PR8/A/34 (red ribbon), Memphis (yellow ribbon) and Hokkaido (blue ribbon) viruses according to “de novo” modeling approach and PEP-FOLD server (described in materials and methods section).