Strain and host-cell dependent role of type-1 fimbriae in the adherence phenotype of super-shed Escherichia coli O157:H7.

Autor: Katani R; The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA., Kudva IT; Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, USA. Electronic address: Indira.kudva@usda.gov., Srinivasan S; The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA., Stasko JB; Microscopy Services, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, USA., Schilling M; The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA., Li L; Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, USA., Cote R; The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA., DebRoy C; Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, USA., Arthur TM; Roman L. Hruska U.S. Meat Animal Research Center, Agricultural Research Service, U.S. Department of Agriculture, Clay Center, NE, USA., Sokurenko EV; Department of Microbiology, University of Washington, Seattle, WA, USA., Kapur V; The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA, USA; Department of Animal Science, The Pennsylvania State University, University Park, PA, USA. Electronic address: vkapur@psu.edu.
Jazyk: angličtina
Zdroj: International journal of medical microbiology : IJMM [Int J Med Microbiol] 2021 May; Vol. 311 (4), pp. 151511. Date of Electronic Publication: 2021 May 05.
DOI: 10.1016/j.ijmm.2021.151511
Abstrakt: Super-shed (SS) Escherichia coli O157 (E. coli O157) demonstrate a strong, aggregative, locus of enterocyte effacement (LEE)-independent adherence phenotype on bovine recto-anal junction squamous epithelial (RSE) cells, and harbor polymorphisms in non-LEE-adherence-related loci, including in the type 1 fimbriae operon. To elucidate the role of type 1 fimbriae in strain- and host-specific adherence, we evaluated the entire Fim operon (FimB-H) and its adhesion (FimH) deletion mutants in four E. coli O157 strains, SS17, SS52, SS77 and EDL933, and evaluated the adherence phenotype in bovine RSE and human HEp-2 adherence assays. Consistent with the prevailing dogma that fimH expression is genetically switched off in E. coli O157, the ΔfimHSS52, ΔfimB-HSS52, ΔfimB-HSS17, and ΔfimHSS77 mutants remained unchanged in adherence phenotype to RSE cells. In contrast, the ΔfimHSS17 and ΔfimB-HSS77 mutants changed from a wild-type strong and aggregative, to a moderate and diffuse adherence phenotype, while both ΔfimHEDL933 and ΔfimB-HEDL933 mutants demonstrated enhanced binding to RSE cells (p < 0.05). Additionally, both ΔfimHSS17 and ΔfimHEDL933 were non-adherent to HEp-2 cells (p < 0.05). Complementation of the mutant strains with their respective wild-type genes restored parental phenotypes. Microscopy revealed that the SS17 and EDL933 strains indeed carry type 1 fimbriae-like structures shorter than those seen in uropathogenic E. coli. Taken together, these results provide compelling evidence for a strain and host cell type-dependent role of fimH and the fim operon in E. coli O157 adherence that needs to be further evaluated.
(Published by Elsevier GmbH.)
Databáze: MEDLINE
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