Role of the external loops in the formation of antigenic structure of OmpF porin from Yersinia pseudotuberculosis

Abstract

Event Abstract Back to Event Role of the external loops in the formation of antigenic structure of OmpF porin from Yersinia pseudotuberculosis Olga Portnyagina1*, Olga Novikova2, Olga Sidorova3 and Valentina Khomenko4 1 G.B. Elyakov Pacific Institute of Bioorganic Chemistry Far Eastern Branch, Russian Academy of Sciences, Molecular Immunology, Russia 2 G.B. Elyakov Pacific Institute of Bioorganic Chemistry Far Eastern Branch, Russian Academy of Sciences, Russia 3 G.B. Elyakov Pacific Institute of Bioorganic Chemistry Far Eastern Branch, Russian Academy of Sciences, Molecular Immunology, Russia 4 G.B. Elyakov Pacific Institute of Bioorganic Chemistry Far Eastern Branch, Russian Academy of Sciences, Russia Porins are the components of Gram-negative bacteria outer membrane (OM) playing a crucial role at the pathogen - host interrelations. Porins are the factors of microbial pathogenicity, participating in the forming of protective immunity at the same time. We have investigated the antigenic structure of the recombinant porin from OM of Yersinia pseudotuberculosis, the causative agents of pseudotuberculosis, using polyclonal antibodies against the full -sized OmpF porin (RP) and against the mutant porins with deletions of the external loops of the protein (del1, del4, del6, del8). As result of refolding conducted by dialysis and ion-exchange chromatography, the recombinant proteins were obtained as trimers and were used for immunization. It is interesting to note the most immunogenicity of del4 and del6 samples for mice, compared with RP. Perhaps, the absence of the loop sites of the protein sequence makes some of T-epitopes more "accessible" to form a ternary complex of antigen / T-receptor / MHC receptor. Deletion loops L1, by contrast, led to 50% loss of antigenic epitopes involved in the formation of the humoral immune response. Analysis of the interaction of specific antibodies against mutant proteins with RP as antigen showed no effect of the lack of loops L6 and L8 on the structure of B-epitopes formation as soon as the efficiency of antibody - antigen binding is similar for the RP and for the mutants. At the same time, deletion of loops L1 and L4 cause loss of 10% and 20% of antigenic epitopes, respectively. Keywords: Yerinia pseudotuberculosis, OmpF porin, antigenic structure, external loops, recombinant protein Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Host-pathogen interactions Citation: Portnyagina O, Novikova O, Sidorova O and Khomenko V (2013). Role of the external loops in the formation of antigenic structure of OmpF porin from Yersinia pseudotuberculosis. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.00285 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 13 Mar 2013; Published Online: 22 Aug 2013. * Correspondence: Dr. Olga Portnyagina, G.B. Elyakov Pacific Institute of Bioorganic Chemistry Far Eastern Branch, Russian Academy of Sciences, Molecular Immunology, Vladivostok, 690022, Russia, odd64@mail.ru Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Olga Portnyagina Olga Novikova Olga Sidorova Valentina Khomenko Google Olga Portnyagina Olga Novikova Olga Sidorova Valentina Khomenko Google Scholar Olga Portnyagina Olga Novikova Olga Sidorova Valentina Khomenko PubMed Olga Portnyagina Olga Novikova Olga Sidorova Valentina Khomenko Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.