LPS

Definition

LPS (Lipopolysaccharide) is a major component of the outer membrane of Gram-negative bacteria, acting as an endotoxin. It plays a crucial role in triggering strong immune responses and can lead to conditions like septic shock.

5 Must Know Facts For Your Next Test

1. LPS consists of three parts: lipid A, core polysaccharide, and O antigen.
2. The lipid A component is responsible for the toxic effects associated with LPS.
3. LPS can activate the innate immune system by binding to Toll-like receptor 4 (TLR4).
4. High levels of LPS in the bloodstream can cause severe inflammatory responses and septic shock.
5. LPS is a key virulence factor for many Gram-negative pathogens such as Escherichia coli and Salmonella.

Review Questions

• What are the three main components of LPS?
• How does LPS interact with the immune system to induce an inflammatory response?
• Why is lipid A considered the toxic component of LPS?

Related terms

Endotoxin: A toxin that is a structural molecule of the bacteria that is recognized by the immune system.

Toll-like receptor 4 (TLR4): A protein that plays a vital role in pathogen recognition and activation of innate immunity.

Septic Shock: A severe condition caused by overwhelming infection leading to low blood pressure and organ failure.