Question

Name the enzyme present in tears that prevents eye infection.

Answer 1

Hint: Human secretions such as tears, human milk, mucus, and saliva have certain antimicrobial and glycoside hydrolase enzymes that protect organs from pathogenic microbes and prevent infections.

Complete step by step answer:
Lysozyme is an enzyme found in human secretions like tears as well as saliva, human milk, mucus, etc and works on the cell wall of bacteria to catalyze the breakdown of certain carbohydrates in it. Thus, it prevents infection caused by these bacteria.

Additional Information: Lysozyme, also known as muramidase or N-acetylmuramide glycohydrolase is an enzyme abundantly found in the secretion of the human body such as tears, saliva, human milk, etc. This enzyme is antimicrobial and is a part of the innate immune system as it has the ability to kill harmful bacteria by causing lysis of the bacteria. By lysis we mean it can break a major component of the bacterial cell wall named peptidoglycan by hydrolyzing the 1,4-beta-linkage between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in it. Apart from human secretion, these are also found in cytoplasmic granules of the macrophages and the PMNs (polymorphonuclear neutrophils), and in egg whites.

Note: The lysozyme enzyme has various roles on the therapeutic side as well. Human lysozyme milk is used in piglets for faster recovery from diarrheal disease caused by E.coli. It is also associated with bronchopulmonary dysplasia in newborns. In case, children can't get the benefits of human breastfeeding, a new line of goats was developed and their milk is used to treat them. Though they have several benefits, excessive secretion of lysozyme in the blood can cause kidney failure and low blood potassium as well.