Vibrionaceae: Genera - Vibrio
27 October 2020 22:18
Vibrionaceae: Genera - Vibrio
Vibrionaceae is very similar genetically to the members of the Enterobacteriaceae.
Vibrionaceae are Gram-negative organisms and facultative anaerobes, capable of fermentation.
They contain oxidase and have one or more flagella, which are generally polar.
Within the Vibrio genera there are over 50 species. But focus on 3 main pathogens:
1. V.cholerae (waterborne infections)
2. V.parahaemolyticus (food-shellfish infections)
3. V.vulnificus (wound infections)
Similarities with members of Enterobacteriaceae:
• Gamma proteobacteria, Gram negative rods (sometimes curved)
• Facultative anaerobes/ fermentative (can survive in aerobic conditions)
• Similar genome size - 4-5 Mbp
• Similar G+C content - 47%
• Genetically tractable (easy to manipulate the genome)
Differences with members of Enterobacteriaceae:
• 2 Chromosomes
• Single polar flagella (high motility)
• Most oxidase positive
• Most live in aquatic habitats (fresh water to salt water conditions)
Vibrio cholerae:
There are over 200 serotypes - O- antigen serogroups. Vibrio cholerae had one of the largest impact
on society in terms of the number of infectious case historically recorded.
O1 and O139: Pan/ epidemic cholera:
This serogroup caused the significant amount of human disease now and historically. O1 serogroup
specifically caused the pandemic and epidemic cholera. This serogroup contains the virulence factor:
Cholera toxin (CT). It can be transmitted via ingesting contaminated water (waterborne) or transfer
directly from person to person. Causes watery diarrhoea in individuals.
Non-O1, Non-O139: Sporadic cases:
These serogroups of vibrio cholerae can still cause disease in human. But tends to be spread in
isolated cases than in population. Can cause gastroenteritis infection, which is usually an
inflammatory response, mild diarrhoea. Virulence factor may not be involved in the disease (cholera
toxin - negative). The pathogen can be transmitted through water and ingestion of shellfish.
V.cholerae O1 impact:
• Acute secretory diarrhoeal disease
• Endemic to 50 countries, and a public health problem for the native population and for
travellers to these regions.
• This ancient disease (5th century BC) remains a considerable social and economic
burden despite nearly 150 years of study.
Vibrio Page 1
27 October 2020 22:18
Vibrionaceae: Genera - Vibrio
Vibrionaceae is very similar genetically to the members of the Enterobacteriaceae.
Vibrionaceae are Gram-negative organisms and facultative anaerobes, capable of fermentation.
They contain oxidase and have one or more flagella, which are generally polar.
Within the Vibrio genera there are over 50 species. But focus on 3 main pathogens:
1. V.cholerae (waterborne infections)
2. V.parahaemolyticus (food-shellfish infections)
3. V.vulnificus (wound infections)
Similarities with members of Enterobacteriaceae:
• Gamma proteobacteria, Gram negative rods (sometimes curved)
• Facultative anaerobes/ fermentative (can survive in aerobic conditions)
• Similar genome size - 4-5 Mbp
• Similar G+C content - 47%
• Genetically tractable (easy to manipulate the genome)
Differences with members of Enterobacteriaceae:
• 2 Chromosomes
• Single polar flagella (high motility)
• Most oxidase positive
• Most live in aquatic habitats (fresh water to salt water conditions)
Vibrio cholerae:
There are over 200 serotypes - O- antigen serogroups. Vibrio cholerae had one of the largest impact
on society in terms of the number of infectious case historically recorded.
O1 and O139: Pan/ epidemic cholera:
This serogroup caused the significant amount of human disease now and historically. O1 serogroup
specifically caused the pandemic and epidemic cholera. This serogroup contains the virulence factor:
Cholera toxin (CT). It can be transmitted via ingesting contaminated water (waterborne) or transfer
directly from person to person. Causes watery diarrhoea in individuals.
Non-O1, Non-O139: Sporadic cases:
These serogroups of vibrio cholerae can still cause disease in human. But tends to be spread in
isolated cases than in population. Can cause gastroenteritis infection, which is usually an
inflammatory response, mild diarrhoea. Virulence factor may not be involved in the disease (cholera
toxin - negative). The pathogen can be transmitted through water and ingestion of shellfish.
V.cholerae O1 impact:
• Acute secretory diarrhoeal disease
• Endemic to 50 countries, and a public health problem for the native population and for
travellers to these regions.
• This ancient disease (5th century BC) remains a considerable social and economic
burden despite nearly 150 years of study.
Vibrio Page 1
