Recombinant Production of a Chimeric Protein Containing StxB, Eae, Cfab, and LTB Proteins in Hairy Roots of Nicotiana tabaccum

The technology of recombinant protein production has revolutionized biological, pharmaceutical, and medical researches. Plants are appropriate systems for the production of recombinant proteins. In the present study, a chimeric gene encoding a chimeric protein containing StxB, Eae, CfaB, and LTB as a candidate vaccine against enterotoxigenic and enterohemorrhagic E. coli, was transferred to the hairy root of the tobacco plant and its expression was analyzed. For this aim, the plant-based codon-optimized gene, which was synthetically cloned in pBI121 binary vector, was transferred into Agrobacterium rhizogenes competent cells. A. rhizogenes cells containing pBI121+secl were transferred into sterile Nicotiana tabaccum plants by direct and indirect methods. Finally, the expression of recombinant protein was analyzed by the ELISA method. The transformation of A. rhizogenes cells and Tobacco plants was confirmed by PCR amplification of a fragment of the chimeric gene with specific primers. SDS-PAGE and ELISA analysis showed the successful expression of the chimeric recombinant protein. In conclusion, it was shown that the hairy roots of tobacco plant is a proper expression system for the recombinant production of SECL protein. The protein can be used for mice's immunization against enterotoxigenic and enterohemorrhagic E. coli strains.