Open AccessShiga toxins decrease enterohaemorrhagic E scherichia coli survival within A canthamoeba castellanii
Author(s) -
Chekabab Samuel M.,
Daigle France,
Charette Steve J.,
Dozois Charles M.,
Harel Josée
Publication year - 2013
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/1574-6968.12158
Subject(s) - microbiology and biotechnology , acanthamoeba , biology , pathogen , escherichia coli , gentamicin protection assay , human pathogen , amoeba (genus) , bacteria , biochemistry , genetics , western blot , gene
Enterohaemorrhagic E scherichia coli ( EHEC ) are zoonotic pathogens transmitted to humans through contaminated water or bovine products. One of the strategies used by pathogenic bacteria to survive in aquatic environments is using free‐living amoebae as hosts. A canthamoeba castellanii is an amoeba known to host several waterborne pathogens. This study investigates the survival of EHEC with A . castellanii , which could contribute to its spread and transmission to humans. We used a gentamicin protection assay as well as fluorescence and electron microscopy to monitor the intra‐amoebae survival of EHEC O 157: H 7 over 24 h. The results showed that EHEC were able to survive within A . castellanii and that this survival was reduced by S higa toxins ( S tx) produced by EHEC . A toxic effect mediated by S tx was demonstrated by amoebae mortality and LDH release during co‐culture of EHEC and amoeba. This work describes the ability of EHEC to survive within A . castellanii , and this host‐pathogen interaction is partially controlled by the S tx. Thus, this ubiquitous amoeba could represent an environmental niche for EHEC survival and transmission.