Cathepsins B , L , H , and S readily cleave BGP at the G 7 A8 bond ; cathepsin L also cleaves at R 43 R44 ; cathepsin B also cleaves at R 44 F45 ; and cathepsin D cleaves only at A 41 Y42 . ^^^ Identification of peptide fragments generated by digestion of bovine and human osteocalcin with the lysosomal proteinases cathepsin B , D , L , H , and S . ^^^