Collagen types I, II, III
Collagen is the main structural protein in the extracellular matrix found in the body’s various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals making 30% of the body protein content. Collagen consists of amino acids bound together to form collagen helix. It is mostly found in connective tissue such as cartilage, bones, tendons, ligaments, and skin.
Types of collagen:
Type I: skin, tendon, vasculature, organs, bone (main component of the organic part of bone)
Type II: cartilage (main collagenous component of cartilage)
Type III: reticulate (main component of reticular fibers), commonly found alongside type I