Table 3.
Natural substitutions at 9 key amino acid positions of H9N2 AIV field strains isolated in China.
| Amino acid position | Substitutions (%)a |
|---|---|
| 125 | S(61.73), G(34.9), D(2.88), Ib,N |
| 248 | G(99.37), E, R |
| 253 | R(98.18), K(1.64), G |
| 296 | K(90.16), R(9.49), N, M |
| 344 | R(98.18), S(1.15), E, K |
| 356 | D(63.19), S(19.07), N(14.27), Y(1.59), V(1.46) |
| 368 | N(41.24), K(27.54), S(17.74), E(8.34), D(3.33), V(1.20), R |
| 369 | D(61.60), G(32.54), N(4.66), K, C, E |
| 400 | S(90.55), R(4.48), N(3.56), G, I, H, T |
a
A total of 2255 NA sequences of Chinese H9N2 isolates available in GenBank (as of 16 June, 2020) were analysed.
b
Proportions of amino acids less than 1% were not shown.