Influenza Virus Hemagglutinin: A Model for Protein N-Glycosylation in Recombinant Escherichia coli

<i>Background:</i> The hemagglutinin molecule of influenza virus is considered as an ideal model to study biological processes as well as the effect of glycosylation on the function of glycoproteins. <i>Objectives:</i> The large subunit of the influenza virus A/New Caledonia/20/99 (H1N1) hemagglutinin (HA1) was expressed in recombinant <i>Escherichia coli</i> containing the glycosylation system of <i>Campylobacter jejuni</i>. This viral glycoprotein contains glycosylation motifs recognized by prokaryotic and eukaryotic oligosaccharyltransferases. <i>Methods:</i> In order to express the hemagglutinin large subunit gene, the gene was amplified using reverse transcription polymerase chain reaction (RT-PCR), and it was cloned in pET22b for periplasmic expression. <i>Results:</i> Western blotting and lectin blotting bands confirmed glycosylation of the HA1 in recombinant <i>E. coli</i>. <i>Conclusion:</i> Such a successful accomplishment of hemagglutinin expression in recombinant <i>E. coli</i> can be used to construct carbohydrates in hemagglutinin molecules of different strains in order to produce effective antigens for vaccine and rapid diagnostic kits against new emerging viruses.