3STI

Crystal structure of the protease domain of DegQ from Escherichia coli


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.222 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Molecular adaptation of the DegQ protease to exert protein quality control in the bacterial cell envelope.

Sawa, J.Malet, H.Krojer, T.Canellas, F.Ehrmann, M.Clausen, T.

(2011) J.Biol.Chem. 286: 30680-30690

  • DOI: 10.1074/jbc.M111.243832
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • To react to distinct stress situations and to prevent the accumulation of misfolded proteins, all cells employ a number of proteases and chaperones, which together set up an efficient protein quality control system. The functionality of proteins in t ...

    To react to distinct stress situations and to prevent the accumulation of misfolded proteins, all cells employ a number of proteases and chaperones, which together set up an efficient protein quality control system. The functionality of proteins in the cell envelope of Escherichia coli is monitored by the HtrA proteases DegS, DegP, and DegQ. In contrast with DegP and DegS, the structure and function of DegQ has not been addressed in detail. Here, we show that substrate binding triggers the conversion of the resting DegQ hexamer into catalytically active 12- and 24-mers. Interestingly, substrate-induced oligomer reassembly and protease activation depends on the first PDZ domain but not on the second. Therefore, the regulatory mechanism originally identified in DegP should be a common feature of HtrA proteases, most of which encompass only a single PDZ domain. Using a DegQ mutant lacking the second PDZ domain, we determined the high resolution crystal structure of a dodecameric HtrA complex. The nearly identical domain orientation of protease and PDZ domains within 12- and 24-meric HtrA complexes reveals a conserved PDZ1 → L3 → LD/L1/L2 signaling cascade, in which loop L3 senses the repositioned PDZ1 domain of higher order, substrate-engaged particles and activates protease function. Furthermore, our in vitro and in vivo data imply a pH-related function of DegQ in the bacterial cell envelope.


    Organizational Affiliation

    Institute of Molecular Pathology, A-1030 Vienna, Austria.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Protease degQ
A, B, C
245Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: degQ (hhoA)
EC: 3.4.21.107
Find proteins for P39099 (Escherichia coli (strain K12))
Go to UniProtKB:  P39099
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.222 
  • Space Group: P 31
Unit Cell:
Length (Å)Angle (°)
a = 70.868α = 90.00
b = 70.868β = 90.00
c = 152.013γ = 120.00
Software Package:
Software NamePurpose
BUSTERrefinement
PHASERphasing
SCALEPACKdata scaling
MAR345dtbdata collection
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-07-27
    Type: Initial release
  • Version 1.1: 2012-01-11
    Type: Database references