Sialic acid

Definition

Sialic acid is a family of acidic sugars commonly found at the outermost end of glycan chains on the surfaces of cells and proteins. It plays crucial roles in cellular recognition and pathogen interactions.

5 Must Know Facts For Your Next Test

1. Sialic acid is often exploited by bacterial and viral pathogens to evade host immune responses.
2. Many influenza viruses bind to sialic acids on host cell surfaces as part of their infection mechanism.
3. Bacterial pathogens such as Neisseria gonorrhoeae use sialylation to avoid detection by the host's immune system.
4. Sialic acids are involved in mediating cell-cell interactions, which can influence pathogen colonization and spread.
5. Enzymes like neuraminidase can cleave sialic acids, aiding in viral release from infected cells.

Review Questions

Related terms

Neuraminidase:

An enzyme that cleaves sialic acids from glycoproteins and glycolipids, facilitating viral release.

Glycan: A polysaccharide or oligosaccharide chain that can be attached to proteins or lipids.

Capsule:

A polysaccharide layer that surrounds some bacterial cells, often containing sialic acid to help evade immune detection.