Collagenase (from Clostridium histolyticum) is a protease with a specificity for the bond between a neutral amino acid (x) and glycine in the sequence Pro-X-Glyc-Pro. This sequence is frequently repeated in collagen and is unique among proteases in its ability to degrade the triple helical native collagen fibrils commonly found in connective tissue. The crude collagenase usually contains clostridiopeptidase A and a number of other proteases along with polysaccharidases and lipases and is commonly used for tissue dissociation.