1K6K | pdb_00001k6k

Crystal Structure of ClpA, an AAA+ Chaperone-like Regulator of ClpAP protease implication to the functional difference of two ATPase domains

• PDB DOI: https://doi.org/10.2210/pdb1K6K/pdb

• Classification: HYDROLASE
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2001-10-16 Released: 2002-09-27 
• Deposition Author(s): Guo, F., Maurizi, M.R., Esser, L., Xia, D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 
  0.263 (Depositor) 
• R-Value Work: 
  0.214 (Depositor) 

Starting Model: experimental

Literature

Crystal structure of ClpA, an HSP100 chaperone and regulator of ClpAP protease

Guo, F., Maurizi, M.R., Esser, L., Xia, D.

(2002) J Biological Chem 277: 46743-46752

• PubMed: 12205096 
• DOI: https://doi.org/10.1074/jbc.M207796200
• Primary Citation Related Structures: 
  1K6K, 1KSF


• PubMed Abstract: 
  

  Escherichia coli ClpA, an Hsp100/Clp chaperone and an integral component of the ATP-dependent ClpAP protease, participates in regulatory protein degradation and the dissolution and degradation of protein aggregates. The crystal structure of the ClpA subunit reveals an N-terminal domain with pseudo-twofold symmetry and two AAA(+) modules (D1 and D2) each consisting of a large and a small sub-domain with ADP bound in the sub-domain junction. The N-terminal domain interacts with the D1 domain in a manner similar to adaptor-binding domains of other AAA(+) proteins. D1 and D2 are connected head-to-tail consistent with a cooperative and vectorial translocation of protein substrates. In a planar hexamer model of ClpA, built by assembling ClpA D1 and D2 into homohexameric rings of known structures of AAA(+) modules, the differences in D1-D1 and D2-D2 interfaces correlate with their respective contributions to hexamer stability and ATPase activity.

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Organizational Affiliation: 
• Laboratory of Cell Biology, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 16.2 kDa 
• Atom Count: 1,193 
• Modeled Residue Count: 142 
• Deposited Residue Count: 143 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ATP-DEPENDENT CLP PROTEASE ATP-BINDING SUBUNIT CLPA	A	143	Escherichia coli	Mutation(s): 0
UniProt
Find proteins for P0ABH9 (Escherichia coli (strain K12)) Explore P0ABH9  Go to UniProtKB:  P0ABH9

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free:  0.263 (Depositor) 
• R-Value Work:  0.214 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 36.021	α = 90
b = 51.965	β = 90
c = 65.1	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
CNS	refinement
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2002-09-27 
Deposition Author(s): Guo, F., Maurizi, M.R., Esser, L., Xia, D.

Revision History  

• Version 1.0: 2002-09-27
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-07
  Changes: Data collection, Database references
• Version 1.4: 2024-04-03
  Changes: Refinement description