Dataset Information

The interaction of Escherichia coli O157?:H7 and Salmonella Typhimurium flagella with host cell membranes and cytoskeletal components.

ABSTRACT: Bacterial flagella have many established roles beyond swimming motility. Despite clear evidence of flagella-dependent adherence, the specificity of the ligands and mechanisms of binding are still debated. In this study, the molecular basis of Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium flagella binding to epithelial cell cultures was investigated. Flagella interactions with host cell surfaces were intimate and crossed cellular boundaries as demarcated by actin and membrane labelling. Scanning electron microscopy revealed flagella disappearing into cellular surfaces and transmission electron microscopy of S. Typhiumurium indicated host membrane deformation and disruption in proximity to flagella. Motor mutants of E. coli O157:H7 and S. Typhimurium caused reduced haemolysis compared to wild-type, indicating that membrane disruption was in part due to flagella rotation. Flagella from E. coli O157 (H7), EPEC O127 (H6) and S. Typhimurium (P1 and P2 flagella) were shown to bind to purified intracellular components of the actin cytoskeleton and directly increase in vitro actin polymerization rates. We propose that flagella interactions with host cell membranes and cytoskeletal components may help prime intimate attachment and invasion for E. coli O157:H7 and S. Typhimurium, respectively.

SUBMITTER: Wolfson EB

PROVIDER: S-EPMC7660914 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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The interaction of Escherichia coli O157 :H7 and Salmonella Typhimurium flagella with host cell membranes and cytoskeletal components.

Wolfson Eliza B EB Elvidge Johanna J Tahoun Amin A Gillespie Trudi T Mantell Judith J McAteer Sean P SP Rossez Yannick Y Paxton Edith E Lane Fiona F Shaw Darren J DJ Gill Andrew C AC Stevens Jo J Verkade Paul P Blocker Ariel A Mahajan Arvind A Gally David L DL

Microbiology (Reading, England) 20201001 10

Bacterial flagella have many established roles beyond swimming motility. Despite clear evidence of flagella-dependent adherence, the specificity of the ligands and mechanisms of binding are still debated. In this study, the molecular basis of Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium flagella binding to epithelial cell cultures was investigated. Flagella interactions with host cell surfaces were intimate and crossed cellular boundaries as demarcated by ac ...[more]

PMID: 32886602

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Dataset Information

The interaction of Escherichia coli O157?:H7 and Salmonella Typhimurium flagella with host cell membranes and cytoskeletal components.

Publications

The interaction of <i>Escherichia coli</i> O157 :H7 and <i>Salmonella</i> Typhimurium flagella with host cell membranes and cytoskeletal components.

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