|Nisbet, David - Dave|
|Donoghue, Ann - Annie|
Submitted to: Biofilms
Publication Type: Abstract Only
Publication Acceptance Date: 8/22/2003
Publication Date: 11/1/2003
Citation: Nava, G., Higgins, S., Bielke, L., Tellez, G., Nisbet, D.J., Anderson, R.C., Donoghue, A.M., Hargis, B. 2003. Biofilm development as an important factor in the virulence of intestinal bacteria. [abstract]. Biofilms. p. 144. Interpretive Summary:
Technical Abstract: Microbial characteristics associated with virulent bacteria include type I pili (TIP), curli production (CP), motility (M), hemolytic reaction (HR), and resistance to the lytic action of host complement (RHC). The role of biofilm production (BP) has not been considered as an important factor of virulence for promoting bacterial colonization of epithelial surfaces, entry into host cells, and exchange of genetic material between bacteria, and competition for intestinal niches. The aim of the present study was to estimate the relationship of selected virulence parameters and BP between pathogenic and endemic intestinal bacteria by comparing the occurrence of these factors. Eight avian pathogenic strains (E. coli O1:K1, E. coli O78:K8, E. coli-Brown, Salmonella enteritidis, Salmonella typhimurium, E. coli O2, E. coli O2:K1, E. coli O1) and seven endemic non-pathogenic intestinal strains (five E. coli isolates, Klebsiella trevisanii, and Kluyvera ascorbata) isolated from avian intestine were evaluated. Assays for TIP, CP, M, HR, CR, and BD were performed to each isolate. All pathogenic strains were positive to CP and RHC. Of these pathogenic strains, only Salmonella typhimurium and E. coli O2:K1 (intermediate RHC) failed to produce appreciable biofilm while the rest of the pathogenic strains were positive in the BP assay. Four of the endemic intestinal strains were positive to CP and produced appreciable amount of biofilm in the BP assay, additionally, three of these bacteria were RHC positive. A casual relationship was not observed between parameters described above and TIP, M, or HR assays in comparison between pathogenic or non-pathogenic bacteria. These results suggest that biofilm production could be an important factor in the virulence of pathogenic bacteria given that it could be used as a advantage to avoid immune, cellular, and chemical systems of host defense. However, BP alone does not necessarily predict virulence as some pathogenic isolates failed to produce biofilm and some non-pathogenic isolates did produce appreciable amounts of biofilm.