2IT0

Crystal structure of a two-domain IdeR-DNA complex crystal form II


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.226 
  • R-Value Observed: 0.229 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Crystal structures, metal activation, and DNA-binding properties of two-domain IdeR from Mycobacterium tuberculosis

Wisedchaisri, G.Chou, C.J.Wu, M.Roach, C.Rice, A.E.Holmes, R.K.Beeson, C.Hol, W.G.

(2007) Biochemistry 46: 436-447

  • DOI: https://doi.org/10.1021/bi0609826
  • Primary Citation of Related Structures:  
    2ISY, 2ISZ, 2IT0

  • PubMed Abstract: 

    The iron-dependent regulator IdeR is a key transcriptional regulator of iron uptake in Mycobacterium tuberculosis. In order to increase our insight into the role of the SH3-like third domain of this essential regulator, the metal-binding and DNA-binding properties of two-domain IdeR (2D-IdeR) whose SH3-like domain has been truncated were characterized. The equilibrium dissociation constants for Co2+ and Ni2+ activation of 2D-IdeR for binding to the fxbA operator and the DNA-binding affinities of 2D-IdeR in the presence of excess metal ions were estimated using fluorescence spectroscopy. 2D-IdeR binds to fxbA operator DNA with similar affinity as full-length IdeR in the presence of excess metal ion. However, the Ni2+ concentrations required to activate 2D-IdeR for DNA binding appear to be smaller than that for full-length IdeR while the concentration of Co2+ required for activation remains the same. We have determined the crystal structures of Ni2+-activated 2D-IdeR at 1.96 A resolution and its double dimer complex with the mbtA-mbtB operator DNA in two crystal forms at 2.4 A and 2.6 A, the highest resolutions for DNA complexes for any structures of iron-dependent regulator family members so far. The 2D-IdeR-DNA complex structures confirm the specificity of Ser37 and Pro39 for thymine bases and suggest preferential contacts of Gln43 to cytosine bases of the DNA. In addition, our 2D-IdeR structures reveal a remarkable property of the TEV cleavage sequence remaining after removal of the C-terminal His6. This C-terminal tail promotes crystal contacts by forming a beta-sheet with the corresponding tail of neighboring subunits in two unrelated structures of 2D-IdeR, one with and one without DNA. The contact-promoting properties of this C-terminal TEV cleavage sequence may be beneficial for crystallizing other proteins.


  • Organizational Affiliation

    Department of Biochemistry and Biomolecular Structure Center, University of Washington, Seattle, Washington 98195, USA.


Macromolecules

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
Iron-dependent repressor ideRC [auth A],
D [auth B],
E [auth C],
F [auth D]
157Mycobacterium tuberculosisMutation(s): 0 
Gene Names: IdeRdtxR
UniProt
Find proteins for P9WMH1 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WMH1 
Go to UniProtKB:  P9WMH1
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP9WMH1
Sequence Annotations
Expand
  • Reference Sequence
Find similar nucleic acids by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains LengthOrganismImage
mbtA/mbtB operator strand 1A [auth E]33N/A
Sequence Annotations
Expand
  • Reference Sequence
Find similar nucleic acids by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains LengthOrganismImage
mbtA/mbtB operator strand 2B [auth F]33N/A
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
ACT
Query on ACT

Download Ideal Coordinates CCD File 
AA [auth D]
BA [auth D]
J [auth A]
K [auth A]
L [auth A]
AA [auth D],
BA [auth D],
J [auth A],
K [auth A],
L [auth A],
P [auth B],
Q [auth B],
U [auth C],
V [auth C],
W [auth C]
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
NI
Query on NI

Download Ideal Coordinates CCD File 
G [auth A]
H [auth A]
I [auth A]
M [auth B]
N [auth B]
G [auth A],
H [auth A],
I [auth A],
M [auth B],
N [auth B],
O [auth B],
R [auth C],
S [auth C],
T [auth C],
X [auth D],
Y [auth D],
Z [auth D]
NICKEL (II) ION
Ni
VEQPNABPJHWNSG-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.226 
  • R-Value Observed: 0.229 
  • Space Group: P 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 54.009α = 108.95
b = 70.363β = 103.08
c = 79.569γ = 94.84
Software Package:
Software NamePurpose
SCALAdata scaling
MOLREPphasing
REFMACrefinement
PDB_EXTRACTdata extraction
MOSFLMdata reduction
CCP4data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2007-02-13
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2023-08-30
    Changes: Data collection, Database references, Derived calculations, Refinement description