TABLE 3

Amino acid residues at the cleavage site of the HA protein of avian H5N2 virusesa

Isolation date (mo/yr)StrainbAmino acid residue at:
HA1 positionHA2 position +1
−6−5−4−3−2−1
1994Ck/Hidalgo/28159-232/94PQRETRG
2005Ck/Ibaraki/1/05PQRETRG
12/2003Ck/TW/1209/03PQREKRG
10/2008Ck/TW/A703-1/08PQRKKRG
1/2012Ck/TW/0101/12PQRKKRG
2/2012Ck/TW/A1997/12PQRRKRG
12/2012Ck/TW/683/12-like (n = 3)PQREKRG
Ck/TW/2593/12PQREKRG
1/2013Ck/TW/1680/13-like (n = 5)PQRKKRG
3/2013Ck/TW/2948/13PQREKRG
Ck/TW/7350/13PQRKKRG
Ck/TW/8994/13-like (n = 3)PQRKKRG
Ck/TW/8996/13PQREKRG
5/2013Ck/TW/4443/13PQREKRG
  • a The glycosylation site at +11 (H3 numbering) is conserved in all viruses in this table.

  • b Three viruses (Ck/TW/1680/13, Ck/TW/8994/13, and Ck/TW/8996/13) were selected for determination of pathogenicity in day-old chickens using the intracerebral pathogenicity index (ICPI).