1PV2

Native Form 2 E.coli Chaperone Hsp31


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.71 Å
  • R-Value Free: 0.286 
  • R-Value Work: 0.221 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A new native EcHsp31 structure suggests a key role of structural flexibility for chaperone function.

Quigley, P.M.Korotkov, K.Baneyx, F.Hol, W.G.J.

(2004) Protein Sci. 13: 269-277

  • DOI: 10.1110/ps.03399604

  • PubMed Abstract: 
  • Heat shock proteins and proteases play a crucial role in cell survival under conditions of environmental stress. The heat shock protein Hsp31, produced by gene hchA at elevated temperatures in Escherichia coli, is a homodimeric protein consisting of ...

    Heat shock proteins and proteases play a crucial role in cell survival under conditions of environmental stress. The heat shock protein Hsp31, produced by gene hchA at elevated temperatures in Escherichia coli, is a homodimeric protein consisting of a large A domain and a smaller P domain connected by a linker. Two catalytic triads are present per dimer, with the Cys and His contributed by the A domain and an Asp by the P domain. A new crystal Form II confirms the dimer and catalytic triad arrangement seen in the earlier crystal Form I. In addition, several loops exhibit increased flexibility compared to the previous Hsp31 dimer structure. In particular, loops D2 and D3 are intriguing because their mobility leads to the exposure of a sizable hydrophobic patch made up by surface areas of both subunits near the dimer interface. The residues creating this hydrophobic surface are completely conserved in the Hsp31 family. At the same time, access to the catalytic triad is increased. These observations lead to the hypothesis for the functioning of Hsp31 wherein loops D2 and D3 play a key role: first, at elevated temperatures, by becoming mobile and uncovering a large hydrophobic area that helps in binding to client proteins, and second, by removing the client protein from the hydrophobic patch when the temperature decreases and the loops adopt their low-temperature positions at the Hsp31 surface. The proposed mode of action of flexible loops in the functioning of Hsp31 may be a general principle employed by other chaperones.


    Organizational Affiliation

    Department of Biochemistry, Department of Chemical Engineering, and Howard Hughes Medical Institute, University of Washington, Seattle, Washington 98195-7742, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Chaperone protein hchA
A, B, C, D, E, F, G, H
283Escherichia coli (strain K12)Gene Names: hchA (yedU, yzzC)
EC: 3.4.11.-, 4.2.1.130
Find proteins for P31658 (Escherichia coli (strain K12))
Go to UniProtKB:  P31658
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.71 Å
  • R-Value Free: 0.286 
  • R-Value Work: 0.221 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 54.487α = 102.95
b = 99.018β = 101.52
c = 116.795γ = 94.19
Software Package:
Software NamePurpose
DENZOdata reduction
AMoREphasing
REFMACrefinement
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-01-13
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance