Shigella spp.
From DrugPedia: A Wikipedia for Drug discovery
Shigella spp.
It is a genus of Gram-negative, non-spore forming rod-shaped bacteria closely related to Escherichia coli and Salmonella. It is only naturally found in humans and apes.
| Kingdom | Bacteria |
|---|---|
| Phylum | Proteobacteria |
| Class | Gamma Proteobacteria |
| Order | Enterobacteriales |
| Family | Enterobacteriaceae |
| Genus | Shigella |
Contents |
Surface Characteristics
Its cell wall contains LPS, a complex macromolecule composed of the biologically active lipid A moiety, covalently attached core oligosaccharide, and distally linked polysaccharide O-side chain. The O-antigen consists of the following residues : -3)-β-D-Quip4NAc-(1-->2)-α-D-Manp [branched to α-L-Rhap-(1-->3)] -(1-->4)-β-D-Galp-(1-->3)-α-D-GlcpNAc-(1-
Transmission
Shigella invade the host through epithelial cells of the large intestine. Using a Type III secretion system acting as a biological syringe, the bacterium injects IpaD protein into cell, triggering bacterial invasion and the subsequent lysis of vacuolar membranes using IpaB and IpaC proteins. It utilizes a mechanism for its motility by which its IcsA protein triggers actin polymerization in the host cell (via N-WASP recruitment of Arp2/3 complexes) in a "rocket" propulsion fashion for cell-to-cell spread.
Pathogenic Activity
It may cause diarrhea, fever, nausea, vomiting, stomach cramps, flatulence, and constipation. Shigella is implicated as one of the pathogenic causes of reactive arthritis worldwide.
Virulence
The stool may contain blood, mucus, or pus. In rare cases, young children may have seizures. Symptoms can take as long as a week to show up, but most often begin two to four days after ingestion. Symptoms usually last for several days but can last for weeks.
