Isolation and Characterization of an Escherichia albertii Strain Producing Three Different Toxins from a Child with Diarrhea

Abstract

Here, we report a bacterium—isolated as the sole pathogen from a child with diarrhea—harboring eae and 2 different cytolethal distending toxin genes (cdt) that are homologous to Escherichia coli cdt-I and cdt-II. The bacterium was originally identified as atypical E. coli by conventional biochemical testing, but was finally identified as E. albertii by multilocus sequence analysis, which is the only method that can currently differentiate E. albertii from E. coli. The Shiga toxin 2f (stx2f) genes were also detected in the strain. Production of these 3 toxins was confirmed by western blotting and/or a cytotoxicity assay using eukaryotic cell lines. This is the first report showing the biological activity of CDT-I, CDT-II, and Stx2f in E. albertii.