1NNF

Crystal Structure Analysis of Haemophlius Influenzae Ferric-ion Binding Protein H9Q Mutant Form


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.10 Å
  • R-Value Free: 0.180 
  • R-Value Work: 0.158 
  • R-Value Observed: 0.159 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

High Resolution Structure of an Alternate Form of the Ferric ion Binding Protein from Haemophilus influenzae

Shouldice, S.R.Dougan, D.R.Skene, R.J.Tari, L.W.McRee, D.E.Yu, R.-H.Schryvers, A.B.

(2003) J Biol Chem 278: 11513-11519

  • DOI: 10.1074/jbc.M211780200
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The periplasmic iron binding protein of pathogenic Gram-negative bacteria performs an essential role in iron acquisition from transferrin and other iron sources. Structural analysis of this protein from Haemophilus influenzae identified four amino ac ...

    The periplasmic iron binding protein of pathogenic Gram-negative bacteria performs an essential role in iron acquisition from transferrin and other iron sources. Structural analysis of this protein from Haemophilus influenzae identified four amino acids that ligand the bound iron: His(9), Glu(57), Tyr(195), and Tyr(196). A phosphate provides an additional ligand, and the presence of a water molecule is required to complete the octahedral geometry for stable iron binding. We report the 1.14-A resolution crystal structure of the iron-loaded form of the H. influenzae periplasmic ferric ion binding protein (FbpA) mutant H9Q. This protein was produced in the periplasm of Escherichia coli and, after purification and conversion to the apo form, was iron-loaded. H9Q is able to bind ferric iron in an open conformation. A surprising finding in the present high resolution structure is the presence of EDTA located at the previously determined anion ternary binding site, where phosphate is located in the wild type holo and apo structures. EDTA contributes four of the six coordinating ligands for iron, with two Tyr residues, 195 and 196, completing the coordination. This is the first example of a metal binding protein with a bound metal.EDTA complex. The results suggest that FbpA may have the ability to bind and transport iron bound to biological chelators, in addition to bare ferric iron.


    Organizational Affiliation

    Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Iron-utilization periplasmic protein
A
309Haemophilus influenzaeMutation(s): 1 
Gene Names: hitA
Find proteins for P35755 (Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd))
Go to UniProtKB:  P35755
Protein Feature View
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDT
Query on EDT

Download CCD File 
A
{[-(BIS-CARBOXYMETHYL-AMINO)-ETHYL]-CARBOXYMETHYL-AMINO}-ACETIC ACID
C10 H16 N2 O8
KCXVZYZYPLLWCC-UHFFFAOYSA-N
 Ligand Interaction
FE
Query on FE

Download CCD File 
A
FE (III) ION
Fe
VTLYFUHAOXGGBS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.10 Å
  • R-Value Free: 0.180 
  • R-Value Work: 0.158 
  • R-Value Observed: 0.159 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 105.101α = 90
b = 75.344β = 90
c = 33.503γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
TRUNCATEdata reduction
MOLREPphasing
REFMACrefinement
HKL-2000data reduction
CCP4data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-04-01
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance