Binding of chondroitin 4-sulfate to cathepsin S regulates its enzymatic activity
Publikation: Beitrag in Fachzeitschrift › Forschungsartikel › Beigetragen › Begutachtung
Beitragende
Abstract
Human cysteine cathepsin S (catS) participates in distinct physiological and pathophysiological cellular processes and is considered as a valuable therapeutic target in autoimmune diseases, cancer, atherosclerosis, and asthma. We evaluated the capacity of negatively charged glycosaminoglycans (heparin, heparan sulfate, chondroitin 4/6-sulfates, dermatan sulfate, and hyaluronic acid) to modulate the activity of catS. Chondroitin 4-sulfate (C4-S) impaired the collagenolytic activity (type IV collagen) and inhibited the peptidase activity (Z-Phe-Arg-AMC) of catS at pH 5.5, obeying a mixed-type mechanism (estimated Ki = 16.5 ± 6 μM). Addition of NaCl restored catS activity, supporting the idea that electrostatic interactions are primarly involved. Furthermore, C4-S delayed in a dose-dependent manner the maturation of procatS at pH 4.0 by interfering with the intermolecular processing pathway. Binding of C4-S to catS was demonstrated by gel-filtration chromatography, and its affinity was measured by surface plasmon resonance (equilibrium dissociation constant Kd = 210 ± 40 nM). Moreover, C4-S induced subtle conformational changes in mature catS as observed by intrinsic fluorescence spectroscopy analysis. Molecular docking predicted three specific binding sites on catS for C4-S that are different from those found in the crystal structure of the cathepsin K-C4-S complex. Overall, these results describe a novel glycosaminoglycan-mediated mechanism of catS inhibition and suggest that C4-S may modulate the collagenase activity of catS in vivo.
Details
Originalsprache | Englisch |
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Seiten (von - bis) | 6487-6498 |
Seitenumfang | 12 |
Fachzeitschrift | Biochemistry : a weekly publication of the American Chemical Society |
Jahrgang | 52 |
Ausgabenummer | 37 |
Publikationsstatus | Veröffentlicht - 17 Sept. 2013 |
Peer-Review-Status | Ja |
Externe IDs
Scopus | 84884275724 |
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Schlagworte
Ziele für nachhaltige Entwicklung
Schlagwörter
- Binding Sites, Cathepsins/antagonists & inhibitors, Chondroitin Sulfates/metabolism, Chromatography, Gel, Collagen Type IV/metabolism, Coumarins/metabolism, Dipeptides/metabolism, Humans, Kinetics, Molecular Docking Simulation, Molecular Dynamics Simulation, Surface Plasmon Resonance