An investigation of the expression and adhesin function of H7 flagella in the interaction ofEscherichia coliO157: H7 with bovine intestinal epithelium

Mahajan, A. et al. (2009) An investigation of the expression and adhesin function of H7 flagella in the interaction ofEscherichia coliO157: H7 with bovine intestinal epithelium. Cellular Microbiology, 11(1), pp. 121-137. (doi: 10.1111/j.1462-5822.2008.01244.x) (PMID:19016776)

Abstract

Enterohaemorrhagic Escherichia coli O157 : H7 is a bacterial pathogen that can cause haemorrhagic colitis and haemolytic uremic syndrome. In the primary reservoir host, cattle, the terminal rectum is the principal site of E. coli O157 colonization. In this study, bovine terminal rectal primary epithelial cells were used to examine the role of H7 flagella in epithelial adherence. Binding of a fliCH7 mutant O157 strain to rectal epithelium was significantly reduced as was binding of the flagellated wild-type strain following incubation with H7-specific antibodies. Complementation of fliCH7 mutant O157 strain with fliCH7 restored the adherence to wild-type levels; however, complementation with fliCH6 did not restore it. High-resolution ultrastructural and imunofluorescence studies demonstrated the presence of abundant flagella forming physical contact points with the rectal epithelium. Binding to terminal rectal epithelium was specific to H7 by comparison with other flagellin types tested. In-cell Western assays confirmed temporal expression of flagella during O157 interaction with epithelium, early expression was suppressed during the later stages of microcolony and attaching and effacing lesion formation. H7 flagella are expressed in vivo by individual bacteria in contact with rectal mucosa. Our data demonstrate that the H7 flagellum acts as an adhesin to bovine intestinal epithelium and its involvement in this crucial initiating step for colonization indicates that H7 flagella could be an important target in intervention strategies.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Smith, Professor David and Roe, Professor Andrew
• Authors: Mahajan, A., Currie, C.G., Mackie, S., Tree, J., McAteer, S., McKendrick, I., McNeilly, T.N., Roe, A., La Ragione, R.M., Woodward, M.J., Gally, D.L., and Smith, D.G.E.
• College/School: College of Medical Veterinary and Life Sciences; College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Cellular Microbiology
• Publisher: Wiley-Blackwell Publishing
• ISSN: 1462-5814
• ISSN (Online): 1462-5822
• Published Online: 02 October 2008