TABLE 2.
Comparison of amino acid substitutions in IBV att strains
| IBV protein | Amino acid (nucleotide) substitution(s)a in the following virus: |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| B/Bris att |
Cold-adapted B/Ann Arbor/1/1966b | Cold-adapted B/USSR/60/1969c | |||||||||
| Predicted | Amplified in MDCK cells |
Amplified in eggs |
Serially passaged in MDCK cells |
Serially passaged in eggs |
|||||||
| P1 | P2 | E1 | E2 | sP1 | sP20 | sE1 | sE15 | ||||
| PB2 | None | NT | NT | NT | NT | None | None | None | S764 (T2315C)Syn | R78Q, M183I, V269I, S630R | 3 mutations |
| PB1 | E391 (G1192), G580 (G1760), A660 (G1999), HA tag | E391 (G1192), G580 (G1760), A660 (G1999), HA tag | E391 (G1192), G580 (G1760), A660 (G1999), HA tag | E391K (G1192A)Rev, G580 (G1760), A660 (G1999), HA tag | E391K (G1192A)Rev, G580 (G1760), A660 (G1999), HA tag | E48K (G163A)NonS, E391 (G1192), G580 (G1760), A660 (G1999), HA tag | E48K (G163A)NonS, E391 (G1192), G580 (G1760), A660 (G1999), HA tag | E391K (G1192A)Rev, G580 (G1760), A660 (G1999), HA tag | E391K (G1192A)Rev, V474I (G1441A)NonS, G580 (G1760), A660 (G1999), HA tag | R433K, I651V, H751Y | |
| PA | None | NT | NT | NT | NT | None | E296 (G917A)Syn | None | K489Q (A1494C)NonS | H160S, S271N, V431M, I495M, Y497H, D589E | 2 mutations |
| HA | None | NT | NT | NT | NT | None | None | None | None | NT | |
| NP | None | NT | NT | NT | NT | None | K341 (A1083G)Syn | None | D377N (G1189A)NonS | T55A, I61D, Y129F, V114A, P410H, A509T, I531T, V534I, D535E | |
| NA | None | NT | NT | NT | NT | None | K371E (A1164G)NonS | None | None | NT | |
| NB | None | NT | NT | NT | NT | None | None | None | None | NT | |
| BM1 | None | NT | NT | NT | NT | None | None | None | None | H159Q, M183V | 1 mutation |
| BM2 | None | NT | NT | NT | NT | None | None | None | None | None | 1 mutation |
| NS1 | None | NT | NT | NT | NT | None | M106T (T361C)NonS | None | None | None | 1 mutation |
| NEP | None | NT | NT | NT | NT | None | None | None | None | None | |
a
NT, not tested; NonS, nonsynonymous mutation (amino acid change); Syn, synonymous mutation (no amino acid change); Rev, reversion to wild-type amino acid sequence. Reversion mutations are underlined. Modifications introduced to attenuate the virus are in boldface.
b
Data from reference 25.
c
Data from reference 70 (sequence information not publicly available; only the number of mutations per segment is given).