Codon Optimization of the Major Antigen Encoding Genes of Diverse Strains of Influenza A Virus

A large number of influenza A virus outbreaks and mortality occurred in the world recently, an urgent attention to develop effective and sufficient quantity of vaccines are needed. Vaccines are generally protein with immunogenic properties and are not expressed in sufficient quantity because of the codon bias, so it is necessary to optimize its codon in the expression host. Codon optimization was used to improve the protein expression in living organisms by increasing the translational efficiency of gene of interest. Two surface antigenic glycoproteins, hemagglutinin (HA) and neuraminidase (NA) are present in influenza A viruses. We have used HA and NA genes from 19 strains of influenza A viruses for codon optimization in E. coli. Both genes of the influenza virus show that the codon adaptation index (CAI) and GC content of the genes in optimized DNA were enhanced significantly (p < 0.01) as compared to wild type. CAI and GC of HA in optimized DNA was enhanced by 3.2 (68.5%) and 1.2 (16.2%) fold respectively, while in NA it was increased by 3.3 (69.7%) and 1.2 (15.8%) fold respectively. Our finding demonstrates that the optimized genes could be useful for better expression in host without any truncated proteins and also helpful for protein folding and function. This work provides new insight in the synthetic biology research.