title: Interaction of cystatin C variants with papain and human cathepsins B, H and L.
abstract: Recombinant human cystatin C and two of its mutants were expressed in Escherichia coli. The recombinant inhibitor was found to be identical to authentic cystatin C as judged by isoelectric focusing (pI 9.2) and kinetics of inhibition of papain and human cathepsins B, H and L. N-terminal truncation of 8 residues resulted in a decrease of isoelectric point (pI 7.8), but the inhibitory properties were similar to those of recombinant cystatin C, suggesting that Leu9 is a critical residue for the inhibition. The mutation of Trp106 to Ser, however, resulted in a decreased affinity of the inhibitor for the enzymes tested, with the largest effect on cathepsin B inhibition (approximately 100-fold increase in Ki).
authors.affiliation: Department of Biochemical Research and Drug Design, KRKA, d.d., Ljubljana, Slovenia. nina.cimerman@krka.si
authors.forename: N
authors.initials: N
authors.lastname: Cimerman
authors.forename: M T
authors.initials: MT
authors.lastname: Prebanda
authors.forename: B
authors.initials: B
authors.lastname: Turk
authors.forename: T
authors.initials: T
authors.lastname: Popovic
authors.forename: I
authors.initials: I
authors.lastname: Dolenc
authors.forename: V
authors.initials: V
authors.lastname: Turk
mesh_terms: D002401:Cathepsin B / Q000037:antagonists & inhibitors; D056655:Cathepsin H; D056668:Cathepsin L; D002403:Cathepsins / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D055316:Cystatin C; D015891:Cystatins / Q000235:genetics / Q000494:pharmacology*; D003546:Cysteine Endopeptidases / Q000494:pharmacology; D015853:Cysteine Proteinase Inhibitors / Q000235:genetics / Q000494:pharmacology*; D010450:Endopeptidases; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D009154:Mutation; D010206:Papain / Q000037:antagonists & inhibitors*; D011994:Recombinant Proteins / Q000494:pharmacology; D017384:Sequence Deletion
chemical_list: C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors; D011994:Recombinant Proteins; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; C534281:CTSL protein, human; D056668:Cathepsin L; C534126:CTSH protein, human; D056655:Cathepsin H; D010206:Papain