Membrane vesicles released by Avibacterium paragallinarum contain putative virulence factors.
Avibacterium paragallinarum, the causative agent of infectious coryza, releases extracellular membrane vesicles (MVs), containing immunogenic proteins, proteases, putative RTX proteins, haemagglutinin, and nucleic acids, into the medium. MVs ranging 50-300 nm in diameter were observed by electron microscopy. They contained immunogenic proteins in the range of 20-160 kDa, detected using vaccinated or experimentally infected chicken sera raised against Av. paragallinarum, but not in pooled sera from specific pathogen-free chickens. Proteolytic activity was not detected in MVs through zymograms; however, immune recognition of high molecular mass bands was observed by Western blotting using an antiprotease serum against Actinobacillus pleuropneumoniae serotype 1 purified protease, suggesting its presence. MVs agglutinated glutaraldehyde-fixed chicken red blood cells indicating the presence of haemagglutinating antigens. Nucleic acids were also detected inside MVs. Avibacterium paragallinarum releases MVs containing putative virulence factors, which could be important in the pathogenesis of infectious coryza.
Carrera de Biología, Facultad de Estudios Superiores Iztacala, UNAM, Estado de México, Mexico.
Marcela O
MO
Ramón Rocha
Octavio
O
García-González
Alma
A
Pérez-Méndez
Jorge
J
Ibarra-Caballero
Victor M
VM
Pérez-Márquez
Sergio
S
Vaca
Erasmo
E
Negrete-Abascal
D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D001427:Bacterial Toxins / Q000276:immunology / Q000378:metabolism; D002645:Chickens; D004269:DNA, Bacterial / Q000378:metabolism; D006388:Hemagglutinins / Q000276:immunology / Q000378:metabolism; D015661:Pasteurellaceae / Q000378:metabolism / Q000472:pathogenicity / Q000648:ultrastructure*; D016871:Pasteurellaceae Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary; D010447:Peptide Hydrolases / Q000276:immunology / Q000378:metabolism; D011201:Poultry Diseases / Q000276:immunology / Q000382:microbiology; D022161:Transport Vesicles / Q000378:metabolism* / Q000648:ultrastructure; D037521:Virulence Factors / Q000378:metabolism*
D000907:Antibodies, Bacterial; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D006388:Hemagglutinins; D037521:Virulence Factors; D010447:Peptide Hydrolases