Table 1.

Analysis of amino acid sequences of surface and internal proteins

	HA clevage site	HA receptor binding sites		NA stalk deletion	PB2	PB1‐F2	PB1	PA	NP	M2	NS1
	335‐339	234	236	63‐65	627E	66N	368V	436E	136L	16E	42S
Virus strains	RSSR↓G	L	G
CK/BJ/94	+	Q	+	−	+	+	I	+	+	G	+
DK/HK/Y280	+	+	+	+	+	+	I	+	+	G	+
CK/SH/F/98	+	Q	+	+	+	+	I	+	+	G	+
QA/HK/Y439	ASNR↓G	Q	+	−	+	+	I	+	+	+	+
QA/HK/G1	+	+	+	38‐40	+	S	I	+	+	+	+
TK/WI/66	VSSR↓G	Q	+	−	+	+	I	+	M	G	+
CK/KR/96	ASYR↓G	Q	+	−	+	+	I	+	+	+	+
CK/JS/1/00	+	+	+	−	+	+	I	+	+	+	+
CK/JX/09	KSSR↓G	+	+	+	+	+	+	+	+	+	+
CK/JX/12	KSSR↓G	+	+	+	+	+	+	+	+	+	+
CK/JX/13	+	+	+	+	+	+	I	+	+	+	+
CK/JX/14	+	+	+	+	+	+	I	+	+	+	+
CK/JX/15	+	+	+	+	+	+	+	+	+	+	+
DK/JX/16	+	+	+	+	+	+	+	+	+	+	+
CK/JX/17	+	+	+	+	+	+	+	+	+	+	+
DK/JX/18	KSSR↓G	+	+	+	+	+	+	+	+	+	+
CK/JX/19	+	+	+	+	+	+	+	+	+	+	+
CK/JX/20	+	+	+	+	+	+	+	+	+	+	+
CK/JX/21	KSSR↓G	+	+	+	+	+	+	+	+	+	+
CK/JX/37	+	+	+	+	+	+	+	+	+	+	+
CK/JX/38	+	+	+	+	+	+	+	+	+	+	+
CK/JX/40	+	+	+	+	+	+	+	+	+	+	+
CK/JX/13Y	KSSR↓G	+	+	+	+	+	+	+	+	V	+
CK/JX/15Y	KSSR↓G	+	+	+	+	+	+	+	+	V	+
CK/JX/69Y	KSSR↓G	+	+	+	+	+	+	+	+	V	+