Figure 3.

Amino acid substitution sites mapped onto the H3-HA molecule, Yokohama, 2016/17 and 2017/18 influenza seasons

HA: haemaglutinin.

Amino acid substitutions at the antigenic sites of H3-HA derived from A/Singapore/INFIMH-16–0019/2016, A/Gunma/140/2017, A/Osaka/163/2017, A/Shimane/112/2017, A/Yokohama/150/2017 or A/Yokohama/138/2017, compared with A/Hong Kong/7127/2014 (Clade 3C.2A), were mapped onto the HA trimer and are indicated by purple, orange, red, green, blue and brown, respectively, with the antigenic sites in parentheses. High-mannose type N-linked glycans (shown in cyan) on the HA trimer of A/Victoria/361/2011 (PDB ID code 4O5N) have been added. Amino acid substitutions involved in the loss of an N-glycosylation site are underlined. The receptor-binding site is shown in yellow.