Figure 3

Mutated sites in the crystal structure of HA protein. The crystal model is HA protein of A/Vietnam/1203/2005, built by the program PyMOL program (V1.4). A is the intact model of HA protein displayed the mutated amino acids in the five antigenic epitope sites. B is the detail profile of the five antigenic epitope sites A, B, C, D and E. The mutated amino acid sites in the 10 avian influenza viruses HA proteins located in the five epitopes were labeled. Amino acids labeled with green were pattern 1 mutation; amino acids labeled with red were pattern 2 mutation; amino acids labeled with blue were pattern 3 mutation; amino acids labeled with orange were pattern 4 mutation (table2).