General description

Cathepsin K is a member of the papain cysteine proteinase family and has been identified as the predominant proteinase responsible for the resorption of the bone matrix. The enzyme cleaves proteins such as collagen type I, collagen type II and osteonectin and therefore plays a role in bone remodeling and resorption in diseases such as osteoporosis, osteolytic bone metastasis and rheumatoid arthritis (Bromme and Okamoto, 1995; Drake, F. et al 1996; Bossard et al, 1996). Cathepsin K is synthesized as an inactive proenzyme (35.1 kDa) that is converted to its mature active form (23.6 kDa) by proteolytic cleavage of its 99-amino-acid propeptide domain. The in-vitro processing of procathepsin K to mature cathepsin K is autocatalytic.

Physical form

2.5 mg/mL solution in 25 mM Na2HPO4 and 500 mM NaCl (pH 7.0).