Lysozyme

Definition

Lysozyme is an enzyme that catalyzes the hydrolysis of the polysaccharides in bacterial cell walls, leading to cell lysis. This enzyme is crucial for the immune system as it provides a first line of defense against bacterial infections by breaking down the protective layers of bacteria, allowing the body to eliminate these pathogens more effectively.

5 Must Know Facts For Your Next Test

1. Lysozyme is found in various body fluids such as tears, saliva, and mucus, where it helps protect against infections.
2. The enzyme works best at a pH of around 7-8, which is typical for many biological environments in the body.
3. Lysozyme can be classified as a glycoside hydrolase because it acts specifically on glycosidic bonds within carbohydrates.
4. This enzyme is also used in food preservation and fermentation processes due to its antibacterial properties.
5. Lysozyme was one of the first enzymes to be crystallized and studied, making it a model enzyme for understanding enzyme structure and function.

Review Questions

• How does lysozyme contribute to the immune response against bacterial infections?
  • Lysozyme contributes to the immune response by hydrolyzing the polysaccharides found in bacterial cell walls, which compromises their structural integrity. This enzymatic action leads to cell lysis, effectively killing the bacteria and preventing infection from spreading. Its presence in bodily fluids such as tears and saliva enhances our first line of defense against pathogens, showcasing its vital role in immunity.
• Discuss the mechanism by which lysozyme catalyzes the hydrolysis of bacterial cell walls.
  • Lysozyme catalyzes hydrolysis by binding to specific sites on the polysaccharides within bacterial cell walls, utilizing its catalytic residues to facilitate the breaking of glycosidic bonds. This interaction distorts the substrate, making it more susceptible to water molecules that participate in the hydrolytic reaction. The enzyme's specificity ensures that it efficiently targets and degrades bacterial components without affecting other cellular structures.
• Evaluate the significance of lysozyme beyond its role in human immunity, particularly in industrial applications.
  • Beyond its role in human immunity, lysozyme holds significant importance in various industrial applications, particularly in food preservation and biotechnology. Its antibacterial properties make it valuable in extending shelf life and maintaining safety in food products by preventing microbial spoilage. In biotechnology, lysozyme is used in laboratory settings for lysing bacterial cells during DNA extraction processes, showcasing its versatility and importance beyond physiological functions.

Related terms

Catalysis: The process by which a substance increases the rate of a chemical reaction without being consumed in the reaction itself.

Enzyme specificity: The ability of an enzyme to select for a specific substrate among many different molecules.

Hydrolysis: A chemical reaction in which water is used to break down the bonds of a particular substance, often involving the splitting of larger molecules into smaller ones.