Shigella

Definition

Shigella is a genus of Gram-negative bacteria known for causing shigellosis, a severe form of dysentery. It primarily affects the gastrointestinal tract by invading and destroying the epithelial cells lining the intestines.

5 Must Know Facts For Your Next Test

1. Shigella species are non-motile, facultative anaerobes that belong to the Enterobacteriaceae family.
2. The four major Shigella species are S. dysenteriae, S. flexneri, S. boydii, and S. sonnei.
3. Shigellosis is typically transmitted via the fecal-oral route through contaminated food or water.
4. Shiga toxin, produced by some strains of Shigella, contributes to its pathogenicity by inhibiting protein synthesis in host cells.
5. Symptoms of shigellosis include diarrhea (often bloody), fever, and stomach cramps starting a day or two after exposure.

Review Questions

• What are the primary modes of transmission for Shigella?
• Which toxin is associated with Shigella's pathogenicity?
• Name at least two symptoms commonly associated with shigellosis.

Related terms

Enterobacteriaceae:

A large family of Gram-negative bacteria that includes many pathogens such as E. coli and Salmonella.

Fecal-Oral Route:

A common pathway for pathogen transmission where infectious agents in fecal particles pass from one person to another orally.

Dysentery:

An inflammatory disorder of the intestine causing severe diarrhea with blood and mucus.