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Determination of Tolerable Fatty Acids and Cholera Toxin Concentrations Using Human Intestinal Epithelial Cells and BALB/c Mouse Macrophages
Published on: May 30, 2013
Cholera stool bacteria repress chemotaxis to increase infectivity
Susan M Butler1, Eric J Nelson, Nityananda Chowdhury
1Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA.
Molecular Microbiology
|April 1, 2006
Summary
Vibrio cholerae in rice-water stools exhibit enhanced infectivity due to a transient, non-chemotactic state. This adaptation, involving reduced CheW-1 levels, aids pathogen transmission during cholera outbreaks.
Area of Science:
- Microbiology
- Infectious Diseases
- Pathogen Transmission
Background:
- Understanding pathogen transmission factors is crucial for controlling outbreaks.
- Vibrio cholerae causes cholera, a severe diarrheal disease, with transmission often linked to contaminated water and food.
Purpose of the Study:
- To investigate factors enhancing Vibrio cholerae transmission from human hosts.
- To identify specific bacterial adaptations contributing to increased oral infectious dose.
Main Methods:
- Comparative analysis of Vibrio cholerae infectivity from human stools versus in vitro cultures using an animal model.
- Assessment of chemotaxis ability in stool-derived V. cholerae via capillary assays.
- Mutational analysis to confirm the role of specific bacterial factors, including CheW-1, in infectivity.
Main Results:
- Vibrio cholerae from rice-water stools showed a 10-fold lower oral infectious dose in animal models compared to in vitro grown bacteria.
- Stool-derived V. cholerae exhibited a chemotaxis defect, associated with reduced levels of the chemotaxis protein CheW-1.
- This transient motile but chemotaxis-defective state was confirmed to enhance V. cholerae infectivity.
Conclusions:
- Pathogen transmission can be significantly enhanced by host-induced bacterial adaptations.
- Vibrio cholerae adopts a specific chemotactic state upon shedding to increase its infectivity and transmission potential.
- This study is the first to report a pathogen altering its chemotactic state in response to human infection to enhance transmission.
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