Question

Which of the following enzymes is involved in the crosslinking of collagen fibrils?

• A. Prolyl hydroxylase
• B. Lysyl hydroxylase
• C. Prolyl oxidase
• D. Lysyl oxidase

Hint:

Lysyl oxidase is crucial for collagen and elastin stability, as it forms cross-links that strengthen collagen fibers and contribute to tissue integrity.

Answer 1

The Correct Option is D

Lysyl oxidase is the key enzyme responsible for the crosslinking of collagen fibrils. It plays a critical role in collagen maturation by catalyzing the oxidative deamination of lysine residues in collagen molecules, which results in the formation of reactive aldehydes. These aldehydes then facilitate the formation of covalent cross-links between collagen molecules, which are crucial for the stability and strength of the collagen fibrils. Although prolyl hydroxylase and lysyl hydroxylase are also involved in collagen biosynthesis by modifying proline and lysine residues, they are not directly responsible for the crosslinking process. Prolyl oxidase is involved in the hydroxylation of proline but does not contribute to the formation of cross-links in collagen. The crosslinking of collagen is vital for its structural function, providing tensile strength and resilience to connective tissues such as skin, tendons, and bones.