2VEC

The crystal structure of the protein YhaK from Escherichia coli


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The Crystal Structure of the Protein Yhak from Escherichia Coli Reveals a New Subclass of Redox Sensitive Enterobacterial Bicupins.

Gurmu, D.Lu, J.Johnson, K.A.Nordlund, P.Holmgren, A.Erlandsen, H.

(2008) Proteins 74: 18

  • DOI: 10.1002/prot.22128

  • PubMed Abstract: 
  • YhaK is a protein of unknown function found in low abundance in the cytosol of Escherichia coli. DNA array studies have revealed that YhaK is strongly up-regulated by nitroso-glutathione (GSNO) and also displays a 12-fold increase in expression durin ...

    YhaK is a protein of unknown function found in low abundance in the cytosol of Escherichia coli. DNA array studies have revealed that YhaK is strongly up-regulated by nitroso-glutathione (GSNO) and also displays a 12-fold increase in expression during biofilm growth of E. coli 83972 and VR50 in human urine. We have determined the YhaK crystal structure and demonstrated that in vitro YhaK is a good marker for monitoring oxidative stresses in E. coli. The YhaK protein structure shows a bicupin fold where the two cupin domains are crosslinked with one intramolecular disulfide bond (Cys10 to Cys204). We found that the third cysteine in YhaK, Cys122, is oxidized to a sulfenic acid. Two chloride ions are found in the structure, one close to the reactive Cys122, and the other on a hydrophobic surface close to a symmetry-related molecule. There are major structural differences at the N-terminus of YhaK compared with similar structures that also display the bicupin fold (YhhW and hPirin). YhaK showed no quercetinase and peroxidase activity. However, reduced YhaK was very sensitive to reactive oxygen species (ROS). The complete, functional E. coli glutaredoxin or thioredoxin systems protected YhaK from oxidation. E. coli thioredoxin reductase and NADPH produced ROS and caused oxidation and oligomerization of reduced YhaK. Taken together, we propose that YhaK is the first of a new sub-class of bicupins that lack the canonical cupin metal-binding residues of pirins and may be involved in chloride binding and/or sensing of oxidative stress in enterobacteria.


    Organizational Affiliation

    Department of Biochemistry and Biophysics, The Arrhenius Laboratories for Natural Sciences, Stockholm University, 10691 Stockholm, Sweden.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PIRIN-LIKE PROTEIN YHAK
A
256Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: yhaK
Find proteins for P42624 (Escherichia coli (strain K12))
Go to UniProtKB:  P42624
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CSO
Query on CSO
A
L-PEPTIDE LINKINGC3 H7 N O3 SCYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.182 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 57.648α = 90.00
b = 57.648β = 90.00
c = 162.092γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
MOLREPphasing
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-07-01
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance