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Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
Published on: May 30, 2017
A potential epidemic factor from the bacteria, Vibrio cholerae WO7
Shalmoli Bhattacharyya1, Jasleen Shant, Nirmal K Ganguly
1Department of Biophysics, Panjab University, Chandigarh, India.
Current Microbiology
|November 9, 2007
Summary
Researchers identified a novel toxin from Vibrio cholerae W07, a strain lacking cholera toxin. This toxin, composed of 58 kDa and 40 kDa subunits, induces apoptosis in HEp-2 cells, suggesting a role in cholera pathogenesis.
Area of Science:
- Microbiology
- Pathogenesis
- Molecular Biology
Background:
- Vibrio cholerae causes cholera, a severe diarrheal disease.
- Pathogenicity is often linked to cholera toxin.
- Epidemic strains can possess alternative virulence factors.
Purpose of the Study:
- To characterize a novel toxin from Vibrio cholerae W07, an epidemic strain lacking the cholera toxin gene.
- To investigate the purification, subunit composition, and biological activity of this new toxin.
Main Methods:
- Modified purification techniques were employed to isolate the novel toxin.
- Toxin subunits were dissociated by heating.
- Subunit characterization and apoptosis induction assays in HEp-2 cells were performed.
Main Results:
- A novel toxin was successfully purified from V. cholerae W07 with improved yield and purity.
- The toxin consists of 58 kDa and 40 kDa subunits, dissociable by heat.
- The 40 kDa subunit functions as the carbohydrate-binding component.
- The purified toxin induced apoptosis in HEp-2 cells.
Conclusions:
- The novel WO7 toxin is a significant virulence factor in Vibrio cholerae W07.
- This toxin plays a potential role in the pathogenesis of cholera associated with this specific strain.
- Further research into this toxin could reveal new therapeutic targets for cholera.
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