title: Epoxysuccinyl peptide-derived affinity labels for cathepsin B.
abstract: Extracellular cysteine proteases, in particular cathepsin B, have been implicated in a variety of pathological processes. Selectively targeting labels of this enzyme are important tools to gain more detailed understanding of its specific roles. Starting from our recently developed irreversible epoxysuccinyl-based inhibitor (R-Gly-Gly-Leu-(2S,3S)-tEps-Leu-Pro-OH, R=OMe), we have synthesized two affinity labels, R=NH-(CH(2))(6)-NH-rhodamine B and R=NH-(CH(2))(6)-NH-biotin. Using MCF-7 cells, the labeled inhibitors were shown to be virtually non-cell-permeant. Moreover, affinity blot analysis with the biotinylated inhibitor allowed a highly sensitive and selective non-radioactive detection of active cathepsin B.
authors.affiliation: Max-Planck-Institut für Biochemie, Martinsried, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Schaschke
authors.forename: I
authors.initials: I
authors.lastname: Assfalg-Machleidt
authors.forename: T
authors.initials: T
authors.lastname: Lassleben
authors.forename: C P
authors.initials: CP
authors.lastname: Sommerhoff
authors.forename: L
authors.initials: L
authors.lastname: Moroder
authors.forename: W
authors.initials: W
authors.lastname: Machleidt
mesh_terms: D000345:Affinity Labels / Q000138:chemical synthesis* / Q000737:chemistry; D001710:Biotin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D002401:Cathepsin B / Q000737:chemistry* / Q000378:metabolism*; D056668:Cathepsin L; D002403:Cathepsins / Q000737:chemistry / Q000378:metabolism; D003546:Cysteine Endopeptidases; D010450:Endopeptidases; D006801:Humans; D007202:Indicators and Reagents; D007700:Kinetics; D015394:Molecular Structure; D009842:Oligopeptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D012235:Rhodamines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000345:Affinity Labels; D007202:Indicators and Reagents; D009842:Oligopeptides; D012235:Rhodamines; C415204:biotin-aminohexylamino-glycyl-glycyl-leucyl-epoxysuccinyl-leucyl-proline; C415203:rhodamine B-aminohexylamino-glycyl-glycyl-leucyl-epoxysuccinyl-leucyl-proline; D001710:Biotin; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; C534281:CTSL protein, human; D056668:Cathepsin L