El plásmido ColV iss+ confiere resistencia al complemento en Escherichia coli Patogénica Aviar

espanolIss (increase survival serum) es una proteina de membrana externa de Escherichia coli que ha sido asociada como molecula de resistencia al sistema del complemento y como factor de virulencia, aunque su modo de accion aun no ha sido bien definido. El objetivo de este trabajo fue analizar la participacion del plasmido ColV iss+ de cepas de Escherichia coli patogenica en la resistencia al complemento para lo cual se realizo la deteccion fenotipica del plasmido ColV en ocho cepas de Escherichia coli patogenica aisladas de pulmon de aves con colisepticemia aviar asi como la deteccion genotipica del gen iss en las cepas portadoras del plasmido ColV. Material y Metodos: La deteccion del gen iss se llevo a cabo mediante la amplificacion de un fragmento del gen por PCR. El efecto bactericida del suero se analizo mediante ensayos de viabilidad bacteriana de la cepa RS4 (ColV iss+) y su isogenica curada de plasmidos RS4 (ColV-) en presencia de suero complementado, asi como de suero descomplementado. Los resultados demostraron que la cepa silvestre RS4 ColV iss+ mostro mayor resistencia a la accion bactericida del complemento en relacion con la isogenica curada RS4 ColV-, sugiriendo que dicho efecto es producido por la presencia del plasmido ColV iss+. EnglishIss (increase serum survival) is an outer membrane protein of Escherichia coli has been associated molecule resistance as the complement system and as a virulence factor, although its mode of action has not been well defined. in the resistence to complement in pathogenic Escherichia coli strains. Phenotypic detection of plasmid ColV was performed in eigth strains of pathogenic Escherichia coli isolated of lung of birds with avian colisepticemia and detection of gene iss was conducted in E. coli strains carrying ColV plasmid. Material and Methods: Detection of gen iss was performed by amplification of a gene fragment by PCR. The bactericidal effect of the serum was analyzed by bacterial viability assays RS4 (ColV iss+) and its isogenic strain plsmidos cured RS4 (ColV-) in the presence of supplemented serum, also decomplemented serum. The results showed that the wild strain iss+ RS4 ColV showed greater resistance to the bactericidal action of complement regarding RS4 ColV- cured isogenic, suggesting that this effect is caused by the presence of plasmid ColV iss+.