Design of H1pHA9 fragment

<p>An HA1 fragment, H1pHA9, defined by stable breakpoints was designed <i>in silico</i>. (A) Shown in stereoview is the cartoon representation of H1N1 A/California/04/2009 HA trimer (PDB ID: 3LZG). Residues 65–286 comprising H1pHA9 (colored grey) have been mapped onto a monomer (orange) of the crystal structure of H1N1 A/California/04/2009 HA. The rest of the molecule is colored green. The mutations introduced in H1pHA9 are colored red. The receptor binding site residues are colored yellow. (B) The mutated residues (red) in H1pHA9 do not contribute to any of the antigenic sites or the receptor binding site (yellow) on HA. The figures were generated in PyMOL (The PyMOL Molecular Graphics System, version 1.2r2, DeLano Scientific, LLC).</p