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Pap Mutant of Avian Pathogenic Escherichia coli O1, an O1:K1:H7 Strain, Is Attenuated In Vivo
Avian Diseases
  • Subhashinie Kariyawasam, Iowa State University
  • Lisa K. Nolan, Iowa State University
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Publication Date
P or Pap fimbriae of avian pathogenic Escherichia coli (APEC) have previously been shown to be important in the pathogenesis of colibacillosis. However, no study has been done to ascertain the effects of deletion of the genes responsible for P fimbrial biogenesis on APEC'sin vitro and/or in vivo characteristics. In the present study, all 11 genes of the pap gene cluster were deleted from APEC O1, the recently sequenced APEC strain, and the wild-type strain was compared to the mutant (ECPAP1) for changes in certain phenotypic characteristics and virulence for chickens. Both APEC O1 and ECPAP1 demonstrated mannose-sensitive agglutination of guinea pig and chicken erythrocytes, but only APEC O1 demonstrated mannose-resistant hemagglutination and P-receptor binding properties. The in vivo experiments revealed that ECPAP1 was markedly attenuated as compared to its wild-type strain APEC O1. These findings suggest that P fimbriae are involved in the virulence of APEC O1.

This article is from Avian Diseases 53, no. 2 (2009): 255–260, doi:10.1637/8519-111708-Reg.1.

Copyright Owner
American Association of Avian Pathologists
Date Available
May 8, 2013
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Citation Information
Subhashinie Kariyawasam and Lisa K. Nolan. "Pap Mutant of Avian Pathogenic Escherichia coli O1, an O1:K1:H7 Strain, Is Attenuated In Vivo" Avian Diseases Vol. 53 Iss. 2 (2009) p. 255 - 260
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