Lysozyme

Definition

Lysozyme is an enzyme that breaks down the cell walls of bacteria, particularly Gram-positive bacteria, by cleaving the bonds in peptidoglycan. It is a crucial component of the innate immune system and is found in various body fluids such as tears, saliva, and mucus.

5 Must Know Facts For Your Next Test

1. It targets the peptidoglycan layer of bacterial cell walls.
2. Lysozyme is abundant in human secretions like tears and saliva.
3. It is especially effective against Gram-positive bacteria due to their thick peptidoglycan layer.
4. Lysozyme plays a significant role in the first line of defense in innate immunity.
5. In addition to humans, lysozymes are found in other animals and plants.

Review Questions

• What type of bacteria is lysozyme most effective against?
• In which body fluids can lysozyme be commonly found?
• What specific part of bacterial cells does lysozyme target?

Related terms

Peptidoglycan:

A polymer that forms a protective layer outside the plasma membrane of most bacteria.

Innate Immunity:

The non-specific first line of defense against pathogens present at birth.

Gram-Positive Bacteria: Bacteria with thick peptidoglycan layers in their cell walls that retain crystal violet stain during Gram staining.