Cloning , Expression and Characterization of Matrix protein ( M 1 ) of highly pathogenic avian influenza H 5 N 1 in Escherichia coli

Avian influenza is highly contagious disease of avian species. Vaccination is considered as one of the efficient tool for controlling the disease. Recombinant avian influenza vaccines comprising haemagglutinin and neuraminidase genes expressed in various platforms has already been investigated and is demonstrated to offer protection in animals. However, because of the high variable nature of these antigens, the less variant matrix protein could be an efficient vaccine candidate against avian influenza. But the applicability of M1 protein as a vaccine is not studied much in animals. Hence, in an effort to develop a matrix protein based sub-unit vaccine against avian influenza, the M1 protein from Eschericia coli was cloned and expressed in BL21-DE3 pLysS. The expression levels were found to be better when the cells were induced with 0.5 mM IPTG and incubated for 3 hrs at 25°C. The rM1 protein was purified using Ni-NTA chromatography under denaturing conditions. The protein was refolded in a reducing buffer conditions which resulted in soluble form of the protein. The total yield of rM1 protein was estimated to be 12-14 mg / liter bacterial culture. Since, this method does not involve complicated purification methods and higher yield can be produced in less than week time, this method of producing rM1 antigen may provide useful insights for the development of faster, cheaper and bulk vaccines for avian influenza pandemic.