| Autor: |
Kjellin J; Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden., Lee D; Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden., Steinsland H; CISMAC, Centre for International Health, Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway.; Department of Biomedicine, University of Bergen, Bergen, Norway., Dwane R; Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden., Barth Vedoy O; Department of Clinical Science, University of Bergen, Bergen, Norway., Hanevik K; Department of Clinical Science, University of Bergen, Bergen, Norway.; National centre for Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital, Bergen, Norway., Koskiniemi S; Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden. |
| Abstrakt: |
Diarrheal diseases are still a significant problem for humankind, causing approximately half a million deaths annually. To cause diarrhea, enteric bacterial pathogens must first colonize the gut, which is a niche occupied by the normal bacterial microbiota. Therefore, the ability of pathogenic bacteria to inhibit the growth of other bacteria can facilitate the colonization process. Although enterotoxigenic Escherichia coli (ETEC) is one of the major causative agents of diarrheal diseases, little is known about the competition systems found in and used by ETEC and how they contribute to the ability of ETEC to colonize a host. Here, we collected a set of 94 fully assembled ETEC genomes by performing whole-genome sequencing and mining the NCBI RefSeq database. Using this set, we performed a comprehensive search for delivered bacterial toxins and investigated how these toxins contribute to ETEC competitiveness in vitro . We found that type VI secretion systems (T6SS) were widespread among ETEC ( n = 47). In addition, several closely related ETEC strains were found to encode Colicin Ia and T6SS ( n = 8). These toxins provide ETEC competitive advantages during in vitro competition against other E. coli , suggesting that the role of T6SS as well as colicins in ETEC biology has until now been underappreciated. |
