collagen
Protein that is the main constituent of connective tissue. Collagen is present in skin, cartilage, tendons, and ligaments. Bones are made up of collagen, with the mineral calcium phosphate providing increased rigidity.
Collagen is made by fibroblast cells that are found in connective tissue. The collagen molecule consists of three protein chains, each about 1,000 amino acids in length, that are entwined in a triple helix. There are 15 known types of collagen that can be divided into fibrillar and nonfibrillar. Fibrillar collagens are found in cartilage, tendons, skin, and bones and the fibrillar structure gives these great strength. Nonfibrillar collagens are found separating the basement membranes, the epithelial layers that line tube and in the cornea. They form networks and sheets.
Collagen therapy
Collagen is used cosmetically to enhance lips and smooth out wrinkles. The collagen, which is extracted mainly from cow hides, is injected into the skin. For wrinkle treatment it is injected into the dermis over six sessions, which have to be repeated after several months as the implants degrade.
| It was identified in a yeastlike fungus in 1996, the first time it has been found in a nonanimal source. |
