Purification Of Recombinant S-layer Protein Of Lactobacillus And The Identification Of Embedded Epitopes From Each-type FMDV

Foot-and-Mouth Disease (FMD) is an acute, febrile and highly contagious disease of cloven-hoofed animals which caused by Foot-and-Mouth Disease virus (FMDV). The outbreaks of FMD can cause serve economical loss to livestock industries. At present, vaccination is one of the most important measures for control of FMD. The common used vaccines are inactivated virus. Although vaccines take an important role in prevent and control FMD, there are many insufficient in the application of vaccine. Such as the purification of viral particles is difficult and the storage conditions of strains are strict, and the vaccination immune effect is not stable and so on. Actually, the common type epidemic of FMD is polymorphic and alternant of A, O and Asia I in china. And there are no crossed immune protections in each types of FMDV, so the curative effect of monovalent vaccine is poor in immunization.In this study, constructed pGEX-SLP and pGEX-SLP-MultiVPl prokaryotic expression vector by IPTG induction expression, which contain antigen gene SLP and SLP-MultiVP1.GST-SLP and GST-SLP-MultiVPl fusion protein with GST, which contain tag protein GST, were purified through the method of affinity chromatography (using Pierce (?) GST Spin Purification Kit) and LiCl precipitation, and evaluated the purified protein. Embedded Epitopes were recognized by each-type FMDV vaccine positive serum with A, O and Asia I in recombinant fusion protein GST-SLP-MultiVPl, and epitopes were recognized by protein SLP-MultiVPl again, which excised GST-tag protein by thrombin. The results of the study were as follows:1. Induced expression recombinant plasmid of pGEX-SLP and pGEX-SLP-MultiVP1in bacilli by IPTG, through the method of SDS-PAGE and Western blotting, the expressed protein was identified, molecular weight of the recombinant fusion protein were71KDa and80KDa respectively, which consist with theoretical value.2. Using Pierce(?) GST Spin Purification Kit affinity chromatography and LiCl precipitation, was carried out on the two kinds of recombinant fusion protein Purification. Higher purified recombinant fusion protein of GST-SLP was obtained, but GST-SLP-Multi VP1was impure.3. Whether GST-tag protein fusion or not, each-type FMDV vaccine positive serum with A, O and Asia I were able to recognize the recombinant fusion protein GST-SLP-MultiVPl embedded in each table. This indicates GST protein were not affected the folding of the recombinant fusion protein SLP, and all types epitopes of FMDV were located on the surface of SLP.This study laid foundations for construction of polyvalent or combination epitope peptide vaccine vector and for research of immunogenicity.