1. SHIGELLA
By: Hunter Reynolds

2. Scientific name
Hylobates concolor

3. Classification
Strains-A study of the nutritional requirements of five strains of Shigella flexneri serotype 3 was carried out.
Shape-Circular DNA genome.
Shigella is its own clade.
Gram negative bacilli

4. Metabolism
Shigella pathogens use a mixed acid fermentation pathway to metabolize substrates. Products of this anaerobic pathway include ethanol, acetic acid, lactic acid, succinic acid, formic acid, and carbon dioxide.
It is an auto transporter.
Facultative anaerobes
The intra- and inter-cellular spreading phenotypes

5. Habitat The intestinal tract of infected humans.
Humans are the only reservoir for Shigella. Transmitted by the fecal-oral route.

6. Special adaptations Transcriptional adaptation
invades epithelial cells as well as macrophages and dendritic cells and escapes into the cytosol soon after invasion
929 and 1,060 genes were up- or down-regulated within HeLa cells and U937 cells
The production of invasion plasmid antigens (Ipa) that have a direct role in the Shigella invasion process
Adhesins that are involved in the adherence of bacteria onto the surface of target epithelial cells

7. Disease causing
Symptoms of shigellosis include diarrhea, bloody stool, abdominal cramps, and fever. The incubation period is 1-3 days
Initial profuse watery diarrhea typically appears first as a result of enterotoxin. Within 1-2 days this progresses to Abdominal cramps and tenesmus, with or without bloody stool. Classic shigellosis presents itself as lower abdominal cramps and stool abundant with blood and pus develops as the Shigella invade the mucosa of the colon.
It is an endotoxin.

8. gram
Shigella is a negative gram.

9. Function
Infection by the gram-negative bacterium Shigella flexneri results in dysentery, an acute inflammatory disease of the colon
the pathogenesis of Shigella infections include bacterial invasion of epithelial cells, escape from the phagosome, and induction of apoptosis in macrophages
Induction of apoptosis is dependent on IpaB binding to the cysteine protease caspase-1 (Casp-1). The activation of this enzyme triggers both apoptosis and release of the proinflammatory cytokine interleukin

10. WOW
In the UK and other developed countries most cases of infection (>90%) are due to S. sonnei and to a much lesser extent S. flexneri, while in developing countries S. dysenteriae and S. flexneri are the commonest species
The organism invades the cells lining the large bowel and multiplies there, killing the cell; this is the cause of the symptoms produced
Shigella infections may also be acquired from contaminated food, vegetables harvested from fields with sewage in it, flies that breed in the infected feces and then contaminate food or by drinking or swimming in contaminated water.

11. By: Hunter Reynolds