The bacterium Vibrio cholerae was discovered more than 150 years ago but remains as one of the main causes of bacterial infectious disease globally, especially in low-income nations where it occurs endemic, and outbreaks of cholera disease can lead to major epidemics.
In addition to causing cholera disease characterized by very severe watery diarrhea, different variants of V. cholerae can cause, for example, wound infections and infections in the ear canal (ear inflammation). If the infection is reaching the bloodstream, it can lead to blood poisoning. Such variants of Vibrio bacteria are common in brackish water, but can be found both in freshwater and saltwater and are also present in such environments in our country.
Scientists from Umeå University have now discovered and characterised the structure and function of a so far unknown Vibrio toxin. A team led by Professor Sun Nyunt Wai at Department of Molecular Biology and MIMS used the worm Caenorhabditis elegans as a predatory host for the bacteria and identified by molecular genetic analysis the V. cholerae genes required for production and release of the new protein toxin, now called MakA.
“In addition to the toxicity of MakA demonstrated with C. elegans, our studies revealed that upon infection of Zebrafish the toxin caused damage in particular to the intestinal system,” explains Sun Nyunt Wai.
Sun Nyunt Wai lrSun Nyunt Wai and her colleagues were also curious about the details of the bacterial release mechanism of the newly discovered toxin from V. cholerae.