STUDIES OF VIABLE BUT NONCULTURABLE VIBRIO PARAHAEMOLYTICU S AT LOW TEMPERATURE UNDER POOR NUTRITION CONDITIONS AND ITS RESUSCITATION

Vibrio parahaemolyticus, a halophilic Gram negative bacterium, causes acute gastroenteritis in humans.This bacteriumis a prevalent foodborne pathogen isolated from coastal water and from a variety of seafood, including fish.Most clinical isolatesare hemolytic on Wagatsuma agar (Kanagawa-positive,KP+) and produce amajorvirulence factor,thermostabledirect hemolysin(TDH).Seawater represents a nutrien-t limiting environment for V.parahaemolyticus.During its persistence in seawater, V.para-haemolyticus is exposed to a variety of environmental stresses, including fluctuations in temperature and cold stress.Many bacteriahave developed strategies for metamorphosis into more or less sophisticated survival forms in response to such harsh environmentalconditions.The formation of (Viable but nonculturable) VBNC cells of bacteria has been proposed as a survival strategy to ad-verse conditions.The VBNC cell is a metabolically one although cells are incapable of undergoing the sustained cellular divisionrequired to form a colony on regular agar media.This state has been demonstrated in other human and fish bacterial pathogens, in-cluding Vibrio vulnificus, Salmonella enteritidis, enterotoxigenic Escherichia coli, Helicobacter pylori, Campylobacter jejuni, Le-gionella pneumophila, Shigella dysenteriae and Aeromonas hydrophila.