Deformation-Dependent Enzyme Cleavage of Collagen

Collagen degradation is a mechanism for normal musculoskeletal development and extracellular matrix (ECM) maintenance, and in response to trauma, disease and inflammation. Matrix metalloproteinases (MMP-1, 8, and 13, the collagenases) are the primary enzymes that act to degrade collagen. These MMPs gain access to the collagen triple helix by binding to the enzyme’s attachment domain along the α-chains, followed by separation (unwinding) of the α-chains to expose the 3/4–1/4 cleavage site, and then cleavage of the α-chain by the enzyme’s catalytic domain [3, 5].