Collagenases are a category of enzymes that speed the hydrolysis of collagen. This task is accomplished by the breaking of peptide bonds within collagen, which is a vital part of the animal extracellular matrix in flesh and connective tissue in the body. Collagenase helps create collagen by cleaving pro-collagen, collagen's precursor, once it is secreted by the cell.
Collagenase was first identified in the 1950s and research progressed quickly. This resulted in its release to the academic world as a commercial isolate in 1959. By the 1980s, several types had been separated and characterized by a number of studies. These multiple classes differed in function and composition, but they also shared many common features.
Collagenase has a molecular weight ranging from 68 kilodaltons (kDa) to 130 Kda due to differing sizes based on the class to which the isolate belongs. The optimal pH for stability ranges from approximately 6.3 to 7.5 with a theoretical isoelectric point of 5.62. In addition, its enzymatic activity means numerous compounds and molecules have the capability of acting as its activator or inhibitor. For example, Ca2+ and Zn2+ ions are two known activators. On the other hand, ethylenediaminetetraacetic acid (EDTA), ethylene glycol tetraacetic acid (EGTA), cysteine, histidine, dithiothreitol (DTT), 2-mercaptoethanol, o-phenanthroline, Hg2+, Pb2+, Cd2+, Cu2+, and Zn2+ are all known inhibitors of collagenase activity.
In the pharmaceutical industry, collagenase has numerous applications. One such application is its use for the isolation of cardiomyocytes from bone, cartilage, and muscle tissue. Another known application is its use to stop the introduction of pathogens in bioprocessing experiments. When using collagenase in research studies, investigators use highly purified preparations purchased from various companies.
Collagenases have also been found to assist in the destruction of extracellular structures in pathogenic bacteria. For example, within the bacterium clostidium, collagenase acts as an exotoxin, which is any toxin secreted by a microorganism to cause damage to the host by disrupting normal cellular functions. Thus, it acts as a virulence factor and helps spread gas gangrene by targeting connective tissue in muscle cells and other body organs.
Within an organism, collagenase production can be induced during an immune response. Cytokines, which are small cell-signaling protein molecules, stimulate fibroblast and osetoblast cells, which causes indirect tissue damage. This has led to collagenases' approval for two medical uses. First is the use of Santyl ointment to remove dead skin from a wound. The second use is for treatment of Duputren’s contracture.