Plesiomonas is a genus of Gram-negative, facultatively anaerobic bacteria belonging to the family Enterobacteriaceae. These bacteria are typically found in water environments such as freshwater, brackish water, and marine habitats. The genus Plesiomonas comprises several species, with Plesiomonas shigelloides being the most commonly recognized.
Plesiomonas bacteria are rod-shaped and motile, possessing a single polar flagellum that aids in their movement. They have the ability to ferment glucose but are unable to break down lactose. The bacteria are oxidase-positive, meaning they produce the enzyme oxidase, which distinguishes them from other related enteric bacteria.
In terms of pathogenicity, Plesiomonas can cause intestinal infections in humans, resulting in gastroenteritis. This is typically characterized by symptoms such as diarrhea, abdominal pain, nausea, and vomiting. The bacteria may also be associated with extraintestinal infections, including wound infections, septicemia, and meningitis, particularly among immunocompromised individuals.
Plesiomonas infections are often acquired through the consumption of contaminated water or food, especially raw or undercooked seafood. Infections can occur both in tropical and temperate regions, and outbreaks have been linked to contaminated drinking water supplies.
Identification of Plesiomonas is usually performed through laboratory testing, including culture techniques and biochemical tests. Proper diagnosis allows for appropriate treatment, usually involving antibiotics targeting Gram-negative bacteria.
Overall, Plesiomonas is a bacterial genus that can cause gastrointestinal and extraintestinal infections in humans, primarily associated with contaminated water and seafood consumption.
