Vibrio parahaemolyticus, a gram-negative marine bacterium, is a worldwide cause of food-borne illness.Vibrio parahaemolyticus inhabits the estuarine, marine and brackish water ecosystems. It is an important human pathogen responsible gastroenteritis associated with contaminated seafood. Prevelent in marine food products, therefore become a significant concern in the production and trade of seafood worldwide .Toxic Factor mainly associated with virulence to cause infection : Gastroenteritis
Necrotizing Fasciitis , Oyster-associated illness. It is a major cause of food poisoning in Asian -India countries .
Organism Details:
Shape and Size
1 . 4 - 2 . 4 ¼ m , R o d O R C o m m a s h a p e d .
Genome Information
vibrio parahaemolyticus is a Gram-negative halophilic, aerobic bacterium.
Vibrio parahaemolyticus O1:Kuk str. FDA_R31 chromosome I. 3362228 bp chromosome ( GI:523825568).It has 4,937genes and 4,731coding proteins, Pseudo Genes: 39, rRNAs: 37 ( 5S, 16S, 23S ),tRNAs: 130,Frameshifted Genes: 23. The GC content of vibrio parahaemolyticus is about 40% and the percentage coding of the bacteria is about 95%.
Food Source
Seafood borne (leading cause), Shellfish (primarily crustacean), Raw Molluscan, Raw Oysters, Eating raw or undercooked shellfish.
Pathological Factor
Virulence mainly associated with two toxin factor and hardly any isolates from the environment have these properties.: Thermostable Direct Hemolysin (TDH), encoded by the tdh genes, responsible for the beta-hemolysis. this protein forms a homotetramer with a central pore 23 Å in diamete. shown to have hemolytic, enterotoxic, cardiotoxic, and cytotoxic activities while TDH-related Hemolysin (TRH) encoded by the trh genes,TRH is predicted to act in a similar manner to lyse cells based upon high sequence homology (68%) between the trh and tdh genes. Major virulence factor of Vibrio associated with Thermostable direct hemolysin (TDH). Several cases of Gastroenteritis caused by Hemolytic TDH.However other virulence factors, such as a shiga-like toxin are also likely be involved. Shiga toxins a highly mobile genetic elements and play a central role in horizontal gene transfer while expression of hemolysin lead to causes.
Disease
V. parahaemolyticus causes three major syndromes of clinical illness, i.e., gastroenteritis, wound infections, and septicemia.The most common syndrome is gastroenteritis; the symptoms include diarrhea with abdominalcramps, nausea, vomiting, headache, and low-grade fever . Sometimes the diarrhea is bloody, watery stool but
unlike that seen in dysentery caused by
Shigella species or in amebiasis. The mean incubation period for V. Parahaemolyticus infection is 15 h (range, 4 to 96 h). The illness is self-limiting and of moderate severity and lasts an average of 3 days in immundefficient patients.