Nematodes—which are found in the sea, fresh water and the soil—include bacteria in their diet and, thus, help keep the level of hygiene high by acting as members of the ‘clean-up crew’ in their environment. The cholera pathogen, however, has found a way to overcome this opponent. „It colonizes the worm’s digestive tract and releases substances that slow down the development and growth of the predator,“ explains Schild. The infected nematodes cannot reach the adult stage and, therefore, cannot reproduce. Among their other findings, the team from Graz has identified the gene that allows Vibrio cholerae to establish itself in and colonize the nematode.
The results of the study also show that the bacterium uses completely different mechanisms to employ this kind of defence than it does when it colonizes the human body. In the future, the researchers want to investigate the interactions between the pathogen and its predator in more detail to develop strategies that could be used to decimate Vibrio cholerae while it is still in the environment. „We’re entering new scientific territory here. If we can gain a better understanding of where and how human pathogens survive between outbreaks, we can hopefully contribute to new approaches that can be taken to prevent and control diseases,“ emphasizes Schild.
Cornelia List, Andreas Grutsch, Claudia Radler, Fatih Cakar, Franz G. Zingl, Kristina Schild-Prüfert, Stefan Schild: Genes Activated by Vibrio cholerae upon Exposure to Caenorhabditis elegans Reveal the Mannose-Sensitive Hemagglutinin to Be Essential for Colonization
mSphere, DOI: 10.1128/mSphereDirect.00238-18
Contact for further inquiries:
Assoc. Prof. Dr. Stefan Schild
Institute for Molecular Biosciences at the University of Graz