Limited Degradation of Gelatin Substrate by Cathepsin D

Cathepsin D has been demonstrated to degrade the protein backbone of proteinpolysaccharide. In this study we present evidence that cathepsin D has only a limited yet specific capacity to degrade gelatin. Similar to the effects of pepsin on collagen, cathepsin D degraded β chains of pure gelatin to α chains but showed no capacity to cleave at a site other than the N-terminal cross-link region. These data suggest that it is unlikely that cathepsin D has a major role in any phase of collagenolysis.