Pandemic influenza vaccine: characterization of A/California/07/2009 (H1N1) recombinant hemagglutinin protein and insights into H1N1 antigen stability

Table 1 Edman sequencing results for H1 A/California/07/2009 trypsin digested fragments

Band ID	Peptide sequence	Cleavage position	Comments
HA0	DTLxIGYHAL	A-17	Mature N-Terminus
HA1	DTLxIGY(H)A	A-17	Mature N-Terminus
HA2	GLFGAIAGFI	R-324	Conserved Cleavage Site
HA2a	RIENLNKKVD	K-419	Additional Cleavage Sites
	IENLNKKVDD	R-420
	KVDDGFLDI(W)	K-426
	VDDGFLDI(W)T	K-427
HA2b	GLFGAIAGFI	R-324	Conserved Cleavage Site
x - unmodified Cys based on the known sequence of H1 A/California/07/2009 rHA

N-terminal sequenced peptides were aligned with the H1 A/California/07/2009 amino acid sequence. The trypsin cleavage sites were identified based on sequence information and ExPASy Proteomic Tools (Peptide Cutter Software).
The trypsin cleavage sites are presented as conserved (for recent H1 strains) or additional cleavage sites (R-420, K-426 and K-427) and additional cleavage site K-419 is shown in bold.

ISSN: 1472-6750