Table 1.

Sequences of the hinge peptide shown for representatives from each subtype (H1–H17), highlighting the conserved position of the histidine in the His¹¹¹ and His¹⁰⁶ groups of HA subtypes

Residue		95	96	97	98	99	100	101	102	103	104	105	106	107	108	109	110	111	112	113	114	115	116	117	118	119	120
His111	H1	N	A	E	L	L	V	L	L	E	N	E	R	T	L	D	F	H	D	S	N	V	R	N	L	Y	E
	H2	N	A	E	L	L	V	L	M	E	N	E	R	T	L	D	F	H	D	S	N	V	K	N	L	Y	D
	H5	N	V	E	L	L	V	L	M	E	N	E	R	T	L	D	F	H	D	S	N	V	N	N	L	Y	D
	H6	N	A	E	L	L	V	L	L	E	N	E	R	T	L	D	L	H	D	A	N	V	K	N	L	Y	E
	H8	N	A	E	L	L	V	L	L	E	N	E	R	T	L	D	L	H	D	A	N	V	K	N	L	Y	E
	H9	N	A	E	L	L	V	L	L	E	N	Q	K	T	L	D	E	H	D	A	N	V	N	N	L	Y	N
	H11	N	A	Q	L	L	V	L	L	E	N	E	K	T	L	D	L	H	D	S	N	V	R	N	L	H	E
	H12	N	A	E	L	L	V	L	L	E	N	Q	K	T	L	D	E	H	D	A	N	V	R	N	L	H	D
	H13	N	A	K	L	L	V	L	L	E	N	D	K	T	L	D	M	H	D	A	N	V	K	N	L	H	E
	H16	N	A	K	L	L	V	L	L	E	N	D	R	T	L	D	L	H	D	A	N	V	R	N	L	H	E
	H17	N	T	E	L	L	V	L	L	E	N	E	R	T	L	D	F	H	D	A	N	V	K	N	L	F	E
His106	H3a	N	A	E	L	L	V	A	L	E	N	Q	H	T	I	D	L	A	D	S	E	M	N	K	L	F	E
	H4	N	A	E	L	L	V	A	L	E	N	Q	H	T	I	D	V	T	D	S	E	M	N	K	L	F	E
	H7	N	A	E	L	L	V	A	M	E	N	Q	H	T	I	D	L	A	D	S	E	M	N	R	L	Y	E
	H10	N	A	E	L	L	V	A	M	E	N	Q	H	T	I	D	M	A	D	S	E	M	L	N	L	Y	E
	H14	N	A	E	L	L	V	A	L	E	N	Q	H	T	I	D	V	T	D	S	E	M	N	K	L	F	E
	H15	N	A	E	L	L	V	A	M	E	N	Q	H	T	I	D	L	A	D	S	E	M	N	K	L	Y	E

The hinge region is highlighted. The subtypes simulated in this study and the hinge histidines are indicated in boldface.

^aFor H3 subtype, both human and avian variants, denoted, respectively, as H3a and H3b in the text, have been simulated. The sequence shown in the table is for H3a, with the sequence of H3b being different only at position 111, where Thr replaces Ala.