DNAse

Definition

DNAse is an enzyme that degrades DNA by cleaving phosphodiester bonds. It is often utilized by certain bacterial pathogens as a virulence factor to evade host immune responses.

5 Must Know Facts For Your Next Test

1. DNAse aids bacterial pathogens in evading neutrophil extracellular traps (NETs) which are composed of DNA.
2. The production of DNAse can increase the invasiveness of bacteria by breaking down host cell DNA.
3. Some bacteria secrete DNAse to facilitate the spread through tissue by reducing the viscosity of pus, which contains high concentrations of DNA from lysed cells.
4. Clinical isolates of Staphylococcus aureus and Streptococcus pyogenes often produce DNAse as a virulence factor.
5. Detection of DNAse activity can be used in diagnostic microbiology to identify specific bacterial species.

Review Questions

• How does DNAse contribute to the virulence of certain bacterial pathogens?
• What role does DNAse play in helping bacteria evade immune responses?
• Why might the presence of DNAse be significant in a clinical diagnostic setting?

Related terms

Neutrophil Extracellular Traps (NETs): Web-like structures composed mainly of DNA released by neutrophils to trap and kill pathogens.

Virulence Factor: Molecules produced by pathogens that contribute to their ability to cause disease.

Phosphodiester Bond: A chemical bond that joins nucleotides in a strand of DNA or RNA.