The Presence of Cathepsin B in Cartilage

Abstract

These experiments demonstrated the presence of an enzyme resembling cathepsin B in rabbit ear cartilage. Some of the properties found for cathepsin B in cartilage sections such as pH optimum, activation by cysteine and inhibition by arginine and iodoacetamide are shared by the enzyme responsible for the autolytic degradation of rabbit ear cartilage at pH 5. Further experiments are required to see whether other known synthetic substrates for cathepsins are hydrolyzed by cartilage enzymes. It should eventually be possible to show whether only cathepsin B is responsible for the autolytic release of chondromucopeptide from cartilage at pH 5 or whether it acts in conjunction with other cathepsins or enzymes.