The Prokaryotic Expression And Immune Characteristic Analysis Of Predicted B Cell Epitope In SS2MRP And SspA

This study focus the prepotent antigenic determinant of MRP(lysozyme release protein) and sspA(subtilisin-like serine protease),which can against the infection of SS2(streptococcus suis type2).MRP and sspA can provide protection force and against the infection of SS2in the reports in the literature.Get the amino acid sequence information and structural information of MRP and sspA from the database NCBI(National Center for Biotechnology Iformation).Remove signal peptides and poisonous force structure, get the prepotent antigenic determinant by using ANTHEPROT5.0to analyse the secondary structure(turning、foldin、helix and random coil)、hydropHily、 accessibility and antigenicity; The predicted91～323aa peptide of sspA(sspA-1) and950-1210aa peptide of MRP(mrp-1) prokaryotic expression vector pET32a-prtS-1and pET32a-mrp-1were constructed by using genetic engineering theory method and then purified by protein purification kits; Analyse the immunogenicity and reactivity by Western blot analysis using the purified MRP-1and sspA-1incubate respectively with immune serum and SS2rehabilitation serum. Observe the role of pHylaxis in SS2infection through the mice survival rate after using the purified protein MRP-1and sspA-1immune mice and injecting the fatal dose of SS2.The recombinant protein MRP-1and sspA-1have been soluble efficiently expressed; Western blot display that the recombinant protein have good immunogenicity and reactivity; Animal experiment results shows that the recombinant protein MRP-1can protect40%mice against the infection of SS2which is50%of the protecting by Inactivated bacteria; The recombinant protein sspA-1can not protect mice from death but delay time of death and get a synergistic effect when it mixxed with MRP-1. This study laid foundation for the application of this protein as a novel efficient immune reagent.