2J0P

Structure of the haem-chaperone Proteobacteria-protein HemS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.192 
  • R-Value Observed: 0.194 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

An Induced Fit Conformational Change Underlies the Binding Mechanism of the Heme Transport Proteobacteria-Protein Hems.

Schneider, S.Sharp, K.H.Barker, P.D.Paoli, M.

(2006) J Biol Chem 281: 32606

  • DOI: 10.1074/jbc.M607516200
  • Primary Citation of Related Structures:  
    2J0R, 2J0P

  • PubMed Abstract: 
  • Bacteria rely on their environment and/or host to acquire iron and have evolved specialized systems to sequester and transport heme. The heme uptake system HemRSTUV is common to proteobacteria, and a major challenge is to understand the molecular mechanism of heme binding and transfer between the protein molecules that underlie this heme transport relay process ...

    Bacteria rely on their environment and/or host to acquire iron and have evolved specialized systems to sequester and transport heme. The heme uptake system HemRSTUV is common to proteobacteria, and a major challenge is to understand the molecular mechanism of heme binding and transfer between the protein molecules that underlie this heme transport relay process. In the Gram-negative pathogen Yersinia enterocolitica, the HemRSTUV system culminates with the cytoplasmic recipient HemS, which stores and delivers heme for cellular needs. HemS belongs to a family of proteins essential and unique to proteobacteria. Here we report on the binding mechanism of HemS based on structural data from its apo- and ligand-loaded forms. This heme carrier protein associates with its cargo through a novel, partly preformed binding pocket, formed between a large beta-sheet dome and a three-helix subdomain. In addition to a histidine interacting with the iron, the complex is stabilized by a distal non-coordinating arginine that packs along the porphyrin plane and extensive electrostatic contacts that firmly anchor the heme propionate groups within the protein. Comparison of apo- and ligand-bound HemS crystal structures reveals striking conformational changes that underlie a "heme-induced fit" binding mechanism. Local shifts in amino acid positions combine with global, rigid body-like domain movements, and together, these bring about a switch from an open, apo-form to a closed, bound state. This is the first report in which both liganded and unliganded forms of a heme transport protein are described, thus providing penetrating insights into its mechanism of heme binding and release.


    Related Citations: 
    • Crystallization and Preliminary X-Ray Diffraction Analysis of the Haem-Binding Protein Hems from Yersinia Enterocolitica.
      Schneider, S., Paoli, M.
      (2005) Acta Crystallogr Sect F Struct Biol Cryst Commun 61: 802

    Organizational Affiliation

    School of Pharmacy and Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
HEMIN TRANSPORT PROTEIN HEMSA345Yersinia enterocoliticaMutation(s): 0 
Gene Names: hemS
Find proteins for P31517 (Yersinia enterocolitica)
Explore P31517 
Go to UniProtKB:  P31517
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM

Download Ideal Coordinates CCD File 
B [auth A]PROTOPORPHYRIN IX CONTAINING FE
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
12P
Query on 12P

Download Ideal Coordinates CCD File 
C [auth A]DODECAETHYLENE GLYCOL
C24 H50 O13
WRZXKWFJEFFURH-UHFFFAOYSA-N
 Ligand Interaction
PEG
Query on PEG

Download Ideal Coordinates CCD File 
E [auth A]DI(HYDROXYETHYL)ETHER
C4 H10 O3
MTHSVFCYNBDYFN-UHFFFAOYSA-N
 Ligand Interaction
MLI
Query on MLI

Download Ideal Coordinates CCD File 
D [auth A]MALONATE ION
C3 H2 O4
OFOBLEOULBTSOW-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.192 
  • R-Value Observed: 0.194 
  • Space Group: I 2 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.941α = 90
b = 77.593β = 90
c = 114.291γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling
PHASERphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-08-29
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Version format compliance