Cloning, In silico analysis, Expression and testing of Immune-potential of outer membrane protein ( Omp 87) of Pasteurella multocida serotype B: 2

Haemorrhagic septicemia (HS) caused by Pasteurella multocida (serotype B: 2) is an important disease of cattle and buffaloes in Asian sub-continent. Presently available vaccines for HS have their own limitations. Efforts have been made to develop better vaccine targeting outer membrane proteins and few of them have shown potential . Omp 87 protein has shown a protective potential against fowl cholera which is caused by Pasteurella multocida serotype A:1, so in present study gene encoding for Omp 87 protein of P. multocida serotype B:2 was cloned, expressed and tested for its immune-potential. An amplicon of 2300 bp was amplified by PCR and cloned in pGEMT vector and sequenced. Sequence was analyzed for open reading frame, structural analysis and epitope mapping. clones containing complete reading frame were sub-cloned in pQE30 expression vector. Recombinant plasmid was transformed in E. coli strain M 15 for over expression. Purified recombinant protein was tested for its antigencity by Western blot analysis. Clones containing Omp 87 Gene were confirmed by colony PCR and enzymatic digestion. Nuleotides sequence of serotype B:2 was compared with Omp87 of serotype A:1 and shown 94.8% similarity. In silico analysis revealed that Omp 87 is a stable trans-membrane protein having nine major B cell epitopes and several T cell epitopes which indicates immunogenic potential of Omp 87 . On expression recombinant protein of 80 kDa was obtained which produced strong signal on western blot. Our findings indicate that Omp 87 may be a potential candidate for r-DNA vaccine against Pasteurella multocida serotype B:2, causative agent of Haemorrhagic septicemia in Asia .