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Published on: November 8, 2016
Bacteriocin Typing of Vibrio cholerae
A N Chakrabarty1, S Adhya, J Basu
1Division of Microbiology, Jadavpur University, Calcutta-32, India.
Infection and Immunity
|March 1, 1970
Summary
Vibrio cholerae bacteriocins are potent bactericidal agents effective against various bacteria. Optimizing production conditions and indicator strain treatment enhances their characterization and typing.
Area of Science:
- Microbiology
- Bacteriology
- Molecular Biology
Background:
- Bacteriocins are ribosomally synthesized antimicrobial peptides with narrow-spectrum activity.
- Vibrio cholerae, the causative agent of cholera, produces bacteriocins that can inhibit other bacteria.
- Understanding bacteriocin production and activity is crucial for potential therapeutic and diagnostic applications.
Purpose of the Study:
- To characterize bacteriocin production by Vibrio cholerae strains.
- To identify optimal conditions for bacteriocin production and activity.
- To determine the diversity of bacteriocins produced by V. cholerae using various indicator strains.
Main Methods:
- Conventional microbiological techniques were employed to demonstrate bacteriocin activity.
- Bacteriocin production was assessed on various agar media.
- Optimal production factors, including buffer concentration, pH, and cold shock, were investigated.
- Indicator organisms were thermally treated to enhance susceptibility.
Main Results:
- Vibrio cholerae bacteriocins exhibited potent diffusible bactericidal activity against enterobacterial and vibrio indicator organisms.
- Abundant bacteriocin production was observed on specific nutrient-rich agars.
- Optimal production occurred at a citrate-phosphate buffer concentration of 0.5-0.7% and pH 7.5-7.6, enhanced by cold shock.
- Thermal treatment of indicator strains at 45°C for 12 minutes increased the percentage of typable strains.
- Eleven distinct bacteriocin types were identified among 425 V. cholerae strains using 8 indicator strains, with 87% being typable.
Conclusions:
- Vibrio cholerae bacteriocins are effective bactericidal agents.
- Specific culture conditions and indicator strain preparation significantly enhance bacteriocin characterization.
- A notable diversity of bacteriocin types exists within V. cholerae strains, suggesting potential for strain typing and further research.
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