TABLE 3.

Susceptibility to NAIs and viral properties caused by the selected substitutions in NA of avian N9 influenza viruses^a

NA amino acid change (N2 numbering)	Location within NA active siteb	Selection NAIc	Oseltamivir		Zanamivir		Peramivir		Mean infectivity (log10 PFU/ml ± SD)	Mean plaque size ± SD (mm)	Genetic stabilityd (% read)
			Mean IC50 ± SD (nM)	Fold change	Mean IC50 ± SD (nM)	Fold change	Mean IC50 ± SD (nM)	Fold change
WT N9	na	na	0.40 ± 0.02	1.0	0.59 ± 0.03	1.0	0.06 ± 0.03	1.0	8.1 ± 0.2	1.51 ± 0.40	na
E119V	Framework	OS	20.01 ± 1.35	49.5	1.79 ± 0.13	3.0	0.08 ± 0.02	1.4	8.6 ± 0.2	1.23 ± 0.16*	V (100)
P120S	–	ZA	0.40 ± 0.01	1.0	0.73 ± 0.03	1.2	0.06 ± 0.04	1.0	8.5 ± 0.2	1.35 ± 0.36	ND
Q136K	–	ZA	0.20 ± 0.04	0.5	71.48 ± 4.47	121.1	3.23 ± 0.89	53.9	7.6 ± 0.2	0.74 ± 0.21*	K (100)
G147R	–	ZA	0.26 ± 0.02	0.6	1.03 ± 0.07	1.7	0.08 ± 0.04	1.5	8.3 ± 0.5	1.28 ± 0.23*	ND
I222M	Framework	OS	7.32 ± 0.27	18.3	2.37 ± 0.74	4.0	0.24 ± 0.02	4.0	8.1 ± 0.3	1.05 ± 0.22*	M (100)
A246T	–	ZA	2.47 ± 0.72	6.2	15.01 ± 1.93	25.4	0.43 ± 0.07	7.2	7.5 ± 0.1	1.51 ± 0.31	T (100)
E259D	–	OS	0.41 ± 0.02	1.0	0.75 ± 0.09	1.3	0.13 ± 0.02	2.2	8.0 ± 0.0	1.54 ± 0.26	ND
H274Y	Framework	Inducede	36.13 ± 12.53	90.3	1.41 ± 0.18	2.4	0.67 ± 0.19	11.2	7.7 ± 0.1	0.89 ± 0.22*	Y (100)
R292K	Catalytic	OS	27,832.00 ± 31,020.67	68,891.1	30.27 ± 5.49	51.3	116.43 ± 6.65	2,067.9	8.5 ± 0.1	1.00 ± 0.16*	K (100)
D339G	–	ZA	0.38 ± 0.02	0.9	0.63 ± 0.10	1.1	0.10 ± 0.01	1.7	8.4 ± 0.2	1.62 ± 0.44	ND

^aSee Table 1, footnote a.

^bSee Table 1, footnote b.

^cSee Table 1, footnote c.

^dSee Table 1, footnote d.

^eSee Table 1, footnote e.