And no attempt has been reported so far in analysis of the ECPs of A. pleuropneumonae. The complete genome sequence of A. pleuropneumonia JL03 provided an essential database for applying immunoproteomic approach to JL03. In the present study, we report this approach to JL03 for the first time which involved the identification of immunogenic proteins from its OMPs and ECPs. Results and Discussion 2-DE profile of the ECPs and OMPs, immunoblotting analysis and identification of immunogenic proteins In
the present study, linear immobilized pH gradient strips (3–10 L IPG 13 cm) and 10% SDS-PAGE gels were used for the prepared samples separation. Figure 1A and 1B show the 2-DE profile of OMPs and ECPs of A. pleuropneumoniae JL03. The 2-DE and immunoblotting Vorinostat manufacturer were repeated three times and the results were reproducible. A total of 110 spots and 98 spots were detected on the silver-stained gels of OMPs and ECPs respectively by the software ImageMaster v 6.01. After immunoblotting analysis with convalescent sera, 28 immunoreactive spots from OMPs (Figure 1A and 1C) were identified, and they represented 17 proteins. Chung et al. recently
identified 47 OM proteins from A. pleuropneumoniae 5b with an optimized extraction protocol based on the sucrose-density gradient which yielded preparations highly enriched for OM proteins and lipoproteins[8], and 10 of the 47 OM proteins were identified as immunogenic proteins in this study. In addition, Rhonda et al. recently demonstrated the sucrose-density PKA activator gradient extraction of outer membranes in Campylobacter jejuni produced purer sample than
carbonate extraction [9] that was applied in this study. So further study needs to be tried on immunoproteomic analysis of other serotypes of A. pleuropneumoniae with the optimized OMP extraction protocol of Chung et al. for search of more immunogenic OMPs. All the 19 immunoreactive spots from ECPs (Figure 1B and 1D) that represented 16 proteins were identified whereas no specific immunoreactive protein spot was observed from OMPs and ECPs using control sera. The detailed Peptide Mass Fingerprinting Protein kinase N1 (PMF) results of the immunoreactive proteins are listed in supplemental table S1 [see additional file 1]. Overall, values of gel estimated pI and MW are matched well with their theoretical ones but some discrepancies still exist. Similar migration for several proteins has been observed in proteomic analysis of other pathogens AZD6094 manufacturer previously[10, 11]. This might be due to the presence of natural isoforms, posttranslational processing, and/or modification, or an artifact caused by sample preparation. Figure 1 2-DE profile of ECPs and OMPs and immunoblot. 2-DE profile of OMPs (A) and ECPs (B) from A. pleuropneumoniae JL03 strain. Preparative gel stained with Silver Nitrate. Immunoblot of OMPs and ECPs from convalescent sera (C) and (D).