Figure 1

Molecular analysis of the cleavage site of HA amino acid sequences (Fig. 1a) and nucleotide sequences (Fig. 1b) of the CK/J1 and CK/J2 viruses, and respective H7N9 virus strains found in first to fifth epidemics (W1~W5). Numbering starts at the N-terminus/open reading frame (ORF, 1~1695nt) of HA. Only the amino acid and nucleotide sequences near the cleavage site regions are shown. In Fig. 1a, the amino acid insertion region is shown by blue break frame; the inserted amino acids of CK/J1 and CK/J2 are shown in yellow shadow; the high pathogenic human strains are shown in red shadow. Figure 1b, nucleotide mutation and insertion are shown in red break frame. Figure 1c, cleavage site sequencing peak maps of CK/J1 and CK/J2. Yellow shadow showing the mutation and nucleotide insertion in the cleavage site. Abbreviations: CK/J1(A/Chicken/Guangdong/J1/2017), CK/J2(A/Chicken/Guangdong/J1/2017), QY/GIRD1(A/Qingyuan/GIRD1/2017), GD/SP440(A/Guangdong/SP440/2017), GD/HP001(A/Guangdong/HP001/2017), GD/17SF003(A/Guangdong/17SF003/2016), GD/17SF006(A/Guangdong/17SF006/2017), HN/02258(A/Hunan/02258/2017), ZJ/6 (A/Zhejiang/6/2017), CK/GD/GZ79(A/Chicken/Guangdong/GZ79/2016), FJ/1(A/Fujian/1/2016), CK/LQ/LQ78(A/Chicken/Longquan/LQ78/2016), ZJ/8(A/Zhejiang/8/2015), GD/15SF043(A/Guangdong/15SF043/2015), HB/344007(A/Hebei/344007/2015), GD/24997(A/Guangdong/24997/2013), AH/09186(A/Anhui/09186/2014), CK/DG/210(A/Chicken/Dongguan/210/2014), SH/1(A/Shanghai/1/2013), CK/SH/S1078(A/Chicken/Shanghai/S1078/2013), GD/2(A/Guangdong/2/2013), LP (Low Pathogenic), HP (High Pathogenic). Amino acid and nucleotide sequence alignments were performed with MegAlign 7.0 (DNASTAR Inc. USA).