Transcript Vibrio vulnificus - University of Louisville

C. Medley F2013
Modified by DYH
Vibrio vulnificus
 Gram negative bacteria
 Gammaproteobacterium
 Halophilic; inhabits oceans and is transmitted
to humans through improperly cooked
seafood
 V. vulnificus is in the same family as the
causative agent of cholera, Vibrio cholera
 Was first isolated in 1976 in the Center for
Disease Control in Atlanta and was named in
1979
 The strain YJ016 (the human pathogen) has
two chromosomes and a plasmid.
http://textbookofbacteriology.net/V.vulnificu
s.html
C. Medley F2013
Modified by DYH
PATHOGENICITY
• Utilizes the cytotoxin RTX secreted through the Type 1 secretion system
(T1SS)
• Most RTX genes are on the small chromosomes
• Can be ingested, causing food poisoning and diarrhea. If V. vulnificus
enters through a wound, it may cause tissue deterioration. In
immunocompromised individuals, especially those with liver damage, V.
vulnificus can cause septicemia. Most individuals infected have blisters and
hemorrhagic necrosis.
• There are 69 ORFs on the plasmid
• Possesses Type IV Pili
• These genes are split amongst the small and large chromosome
• Has a capsule, allowing the bacteria to evade the host immune system
• There is no ORF on present that would assist the bacterium in invading the
host. That is why V. vulnificus must enter the host via the gastrointestinal
tract or through wounds.