Author(s)

Sunita Kumari Yadav¹, Carmelita N. Marbaniang², Vibhuti Sharma¹, Aparna Dixit^1*

¹School of Biotechnology, Jawaharlal Nehru University, New Delhi, India.
²RNA Biology Group, Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany.

Aeromonas hydrophila, a gram negative bacterium is a major fish pathogen and causes major economic losses to aquaculture industry. Outer membrane proteins play a significant role in its survival during different environmental conditions and bacterial pathogenesis. The outer membrane protein R (OmpR) is a member of the two-component regulatory system of Aeromonas hydrophila which differentially regulates the expression of OmpF or OmpC depending on the osmolarity conditions. Role of OmpR has been demonstrated in its virulence in other infectious bacteria and it is found to be a potential drug target/vaccine candidate. However, the OmpR of A. hydrophila has not been characterized. In the present study, we report recombinant expression, purification of the OmpR of A. hydrophila strain Ah17 in salt inducible E. coli GJ1158 cells. Leaky expression of rOmpR was confirmed by Western blot analysis using anti-6 × His antibody. The histidine tagged recombinant OmpR (rOmpR) (~29 kDa) was purified using Ni-NTA affinity chromatography from the soluble fraction of induced E. coli cells. The rOmpR was found to be highly immunogenic with end point titres of greater than 1:80,000. The anti-rOmpR antisera were capable of agglutinating live A. hydrophila cells, thus showing vaccine potential of the rOmpR.

OmpR, Aeromonas, Cross-Reactivity, Outer Membrane Protein, Expression, E. coli GJ1158

Yadav, S. , Marbaniang, C. , Sharma, V. and Dixit, A. (2015) Heterologous Soluble Expression of Recombinant OmpR of Aeromonas hydrophila and Its Immunogenic Potential. Advances in Bioscience and Biotechnology, 6, 443-451. doi: 10.4236/abb.2015.67044.