From: H9N2 influenza virus acquires intravenous pathogenicity on the introduction of a pair of di-basic amino acid residues at the cleavage site of the hemagglutinin and consecutive passages in chickens
Passage number
PB2
HA
NP
NA
M2
271a
29
234
357
391
54
195
51
P0
T
N
L
A
W
I
P1-P5
.b
.
Q
P6
H
D
P7
N/Dc
P8
T/A
N/D
P9
G
P10