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Virulence factors and markers in Escherichia coli from calves with bacteremia
1988
Mohamed Ou Said, A. | Contrepois, M.G. | Der Vartanian, M. | Girardeau, J.P.
Relative pathogenicity of 151 Escherichia coli isolates from 36 calves with bacteremia after necropsy was studied by measurement of the LD50 after mice were inoculated IP with E coli isolates. Study of virulence factors and markers revealed that the pathogenicity of E coli was associated with the production of hydroxamate siderophores and with resistance to serum bactericidal effects. Production of colicins, including colicin V, and of surface antigen 31A was correlated with virulence. The close association between phenotypic expression of virulence factors and markers was consistent with a hypothesis of a localization of genes coding for virulence factors and markers on the same plasmid.
Show more [+] Less [-]Comparison of phenotypic characteristics of Salmonella spp isolated from healthy and ill (infected) chickens
1991
Nolan, L.K. | Wooley, R.E. | Brown, J. | Payeur, J.B.
Phenotypic characteristics of 12 paired, Salmonella serotypes isolated from healthy and ill chickens were compared. Variables compared included antibiotic resistance profiles, production of colicins and siderophores, mannose-sensitive hemagglutination of erythrocytes, resistance to serum complement, carbon source utilization, presence and transmissibility of R plasmids, and invasiveness in primary chicken kidney cell culture. Differences were found between pairs for utilization of carbon sources, mannose-sensitive hemagglutination of erythrocytes, and invasiveness in cell culture.
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