Lysozymes are enzymes that break down bacterial cell walls by catalyzing the hydrolysis of 1,4-beta linkages between N-acetylmuramic acid and the acetyl-D-glucosamine residues in the bacterial wall. Lysozymes can help break down all gram-positive bacteria and some gram-negative bacteria.
Lysozymes function by attacking the peptidoglycan in the cell walls of bacteria. The enzyme also binds to the peptidoglycan molecules and causes them to change their conformational shape. The lysozyme can then break the glycosidic bonds in the peptidoglycan very easily and hydrolyze the bacterial cell wall. Lysozyme is found naturally in the human body and is key to a few different functions. This enzyme occurs in the innate immune system and helps the body fight off bacterial infections. The enzyme is also in human tears and saliva to act as a first defense mechanism to foreign antigens. In many different cancers, lysozyme also plays a role. Cancer cells can produce large amounts of lysozyme, which leads to high concentrations of the enzyme in the bloodstream. High lysozyme blood levels may lead to kidney disease or kidney failure, low blood potassium and low electrolyte levels in the blood. All of these conditions usually improve once a doctor removes the malignant tumor.