3C9E

Crystal structure of the cathepsin K : chondroitin sulfate complex.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.180 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The crystal and molecular structures of a cathepsin K:chondroitin sulfate complex.

Li, Z.Kienetz, M.Cherney, M.M.James, M.N.Bromme, D.

(2008) J.Mol.Biol. 383: 78-91

  • DOI: 10.1016/j.jmb.2008.07.038

  • PubMed Abstract: 
  • Cathepsin K is the major collagenolytic enzyme produced by bone-resorbing osteoclasts. We showed earlier that the unique triple-helical collagen-degrading activity of cathepsin K depends on the formation of complexes with bone-or cartilage-resident g ...

    Cathepsin K is the major collagenolytic enzyme produced by bone-resorbing osteoclasts. We showed earlier that the unique triple-helical collagen-degrading activity of cathepsin K depends on the formation of complexes with bone-or cartilage-resident glycosaminoglycans, such as chondroitin 4-sulfate (C4-S). Here, we describe the crystal structure of a 1:n complex of cathepsin K:C4-S inhibited by E64 at a resolution of 1.8 A. The overall structure reveals an unusual "beads-on-a-string"-like organization. Multiple cathepsin K molecules bind specifically to a single cosine curve-shaped strand of C4-S with each cathepsin K molecule interacting with three disaccharide residues of C4-S. One of the more important sets of interactions comes from a single turn of helix close to the N terminus of the proteinase containing a basic amino acid triplet (Arg8-Lys9-Lys10) that forms multiple hydrogen bonds either to the caboxylate or to the 4-sulfate groups of C4-S. Altogether, the binding sites with C4-S are located in the R-domain of cathepsin K and are distant from its active site. This explains why the general proteolytic activity of cathepsin K is not affected by the binding of chondroitin sulfate. Biochemical analyses of cathepsin K and C4-S mixtures support the presence of a 1:n complex in solution; a dissociation constant, K(d), of about 10 nM was determined for the interaction between cathepsin K and C4-S.


    Organizational Affiliation

    Mount Sinai School of Medicine, Department of Human Genetics, New York, NY 10029, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Cathepsin K
A
215Homo sapiensMutation(s): 0 
Gene Names: CTSK (CTSO, CTSO2)
EC: 3.4.22.38
Find proteins for P43235 (Homo sapiens)
Go to Gene View: CTSK
Go to UniProtKB:  P43235
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
E64
Query on E64

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Download CCD File 
A
N-[N-[1-HYDROXYCARBOXYETHYL-CARBONYL]LEUCYLAMINO-BUTYL]-GUANIDINE
C15 H30 N5 O5
QPQNJAXBPHVASB-QWRGUYRKSA-O
 Ligand Interaction
BDP
Query on BDP

Download SDF File 
Download CCD File 
A
BETA-D-GLUCOPYRANURONIC ACID
D-GLUCURONIC ACID
C6 H10 O7
AEMOLEFTQBMNLQ-QIUUJYRFSA-N
 Ligand Interaction
ASG
Query on ASG

Download SDF File 
Download CCD File 
A
2-DEOXY-2-ACETAMIDO-BETA-D-GALACTOSE-4-SULFATE
C8 H15 N O9 S
WHCJUIFHMJFEFZ-UIAUGNHASA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
E64Kd: 10 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.180 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 42.000α = 90.00
b = 143.900β = 90.00
c = 87.200γ = 90.00
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling
PDB_EXTRACTdata extraction
CNSrefinement
MOLREPphasing
ADSCdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-08-26
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Non-polymer description, Version format compliance
  • Version 1.2: 2016-02-17
    Type: Derived calculations