1R6B

High resolution crystal structure of ClpA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.25 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.234 
  • R-Value Observed: 0.235 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystallographic investigation of peptide binding sites in the N-domain of the ClpA chaperone.

Xia, D.Esser, L.Singh, S.K.Guo, F.Maurizi, M.R.

(2004) J Struct Biol 146: 166-179

  • DOI: 10.1016/j.jsb.2003.11.025
  • Primary Citation of Related Structures:  
    1R6Q, 1R6O, 1R6C, 1R6B

  • PubMed Abstract: 
  • Escherichia coli ClpA, an Hsp100/Clp chaperone and an integral component of the ATP-dependent ClpAP protease, participates in the dissolution and degradation of regulatory proteins and protein aggregates. ClpA consists of three functional domains: an N-terminal domain and two ATPase domains, D1 and D2 ...

    Escherichia coli ClpA, an Hsp100/Clp chaperone and an integral component of the ATP-dependent ClpAP protease, participates in the dissolution and degradation of regulatory proteins and protein aggregates. ClpA consists of three functional domains: an N-terminal domain and two ATPase domains, D1 and D2. The N-domain is attached to D1 by a mobile linker and is made up of two tightly bound, identically folded alpha-helical bundles related by a pseudo 2-fold symmetry. Between the halves of the pseudo-dimer is a large flexible acidic loop that becomes better ordered upon binding of the small adaptor protein, ClpS. We have identified a number of structural features in the N-domain, including a Zn(++) binding motif, several interfaces for binding to ClpS, and a prominent hydrophobic surface area that binds peptides in different configurations. These structural motifs may contribute to binding of protein or peptide substrates with weak affinity and broad specificity. Kinetic studies comparing wild-type ClpA to a mutant ClpA with its N-domain deleted show that the N-domains contribute to the binding of a non-specific protein substrate but not of a folded substrate with the specific SsrA recognition tag. A functional model is proposed in which the N-domains in ClpA function as tentacles to weakly hold on to proteins thereby enhancing local substrate concentration.


    Related Citations: 
    • Crystal structure of ClpA, an Hsp100 chaperone and regulator of ClpAP protease
      Guo, F., Maurizi, M.R., Esser, L., Xia, D.
      (2002) J Biol Chem 277: 46743

    Organizational Affiliation

    Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. dixia@helix.nih.gov



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
ClpA proteinA [auth X]758Escherichia coliMutation(s): 1 
UniProt
Find proteins for P0ABH9 (Escherichia coli (strain K12))
Explore P0ABH9 
Go to UniProtKB:  P0ABH9
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ADP (Subject of Investigation/LOI)
Query on ADP

Download Ideal Coordinates CCD File 
E [auth X], F [auth X]ADENOSINE-5'-DIPHOSPHATE
C10 H15 N5 O10 P2
XTWYTFMLZFPYCI-KQYNXXCUSA-N
 Ligand Interaction
MG
Query on MG

Download Ideal Coordinates CCD File 
B [auth X], C [auth X], D [auth X]MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.25 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.234 
  • R-Value Observed: 0.235 
  • Space Group: P 65
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 124.11α = 90
b = 124.11β = 90
c = 97.049γ = 120
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
SCALEPACKdata scaling
MLPHAREphasing

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-08-24
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance