TABLE 2.
A/CA/7/09 HA variants identified from MDCK cells and introduced by reverse genetics
| Virus | Amino acid at indicated positiona (H3 position) |
Virus titerb in eggs (log10 FFU/ml ± SE) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| 119 (122) | 153 (156) | 154 (157) | 155 (158) | 186 (189) | 222 (225) | 223 (226) | 278 (280) | ||
| V5 | K | K | K | G | A | G | Q | T | 7.4 ± 0.14 |
| V6 | D | R | 7.7 ± 0.14 | ||||||
| V5-119N | N | 8.3 ± 0.06 | |||||||
| V5-119E | E | 8.3 ± 0.07 | |||||||
| V5-153E | E | 8.3 ± 0.05 | |||||||
| V5-154E | E | 8.6 ± 0.05 | |||||||
| V6-186D | D | D | R | 8.4 ± 0.06 | |||||
| V5-186D | D | 8.3 ± 0.15 | |||||||
| V5-119E/186D | E | D | 8.5 ± 0.06 | ||||||
| V6-119N | N | D | R | 7.9 ± 0.20 | |||||
| V6-119N/186D | N | D | D | R | 8.1 ± 0.09 | ||||
| V5-155E | E | 8.4 ± 0.11 | |||||||
| V5-278K | K | 7.6 ± 0.19 | |||||||
| V6-155E | E | D | R | 8.4 ± 0.19 | |||||
| V6-278K | D | R | K | 7.7 ± 0.27 | |||||
a
Amino acid changes from V5 or V6 are shown.
b
Virus titers are mean titers from at least three virus stocks.