2ECS

Lambda Cro mutant Q27P/A29S/K32Q at 1.4 A in space group C2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.40 Å
  • R-Value Free: 0.175 
  • R-Value Work: 0.139 
  • R-Value Observed: 0.141 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Two structures of a lambda Cro variant highlight dimer flexibility but disfavor major dimer distortions upon specific binding of cognate DNA.

Hall, B.M.Roberts, S.A.Heroux, A.Cordes, M.H.

(2008) J Mol Biol 375: 802-811

  • DOI: 10.1016/j.jmb.2007.10.082
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Previously reported crystal structures of free and DNA-bound dimers of lambda Cro differ strongly (about 4 A backbone rmsd), suggesting both flexibility of the dimer interface and induced-fit protein structure changes caused by sequence-specific DNA ...

    Previously reported crystal structures of free and DNA-bound dimers of lambda Cro differ strongly (about 4 A backbone rmsd), suggesting both flexibility of the dimer interface and induced-fit protein structure changes caused by sequence-specific DNA binding. Here, we present two crystal structures, in space groups P3(2)21 and C2 at 1.35 and 1.40 A resolution, respectively, of a variant of lambda Cro with three mutations in its recognition helix (Q27P/A29S/K32Q, or PSQ for short). One dimer structure (P3(2)21; PSQ form 1) resembles the DNA-bound wild-type Cro dimer (1.0 A backbone rmsd), while the other (C2; PSQ form 2) resembles neither unbound (3.6 A) nor bound (2.4 A) wild-type Cro. Both PSQ form 2 and unbound wild-type dimer crystals have a similar interdimer beta-sheet interaction between the beta1 strands at the edges of the dimer. In the former, an infinite, open beta-structure along one crystal axis results, while in the latter, a closed tetrameric barrel is formed. Neither the DNA-bound wild-type structure nor PSQ form 1 contains these interdimer interactions. We propose that beta-sheet superstructures resulting from crystal contact interactions distort Cro dimers from their preferred solution conformation, which actually resembles the DNA-bound structure. These results highlight the remarkable flexibility of lambda Cro but also suggest that sequence-specific DNA binding may not induce large changes in the protein structure.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, AZ 85721, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Phage lambda CroA, B66Escherichia virus LambdaMutation(s): 3 
Gene Names: crolambdap57
Find proteins for P03040 (Escherichia phage lambda)
Explore P03040 
Go to UniProtKB:  P03040
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
ACT
Query on ACT

Download CCD File 
A, B
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
CL
Query on CL

Download CCD File 
B
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
LI
Query on LI

Download CCD File 
B
LITHIUM ION
Li
HBBGRARXTFLTSG-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.40 Å
  • R-Value Free: 0.175 
  • R-Value Work: 0.139 
  • R-Value Observed: 0.141 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 88.689α = 90
b = 26.999β = 103.69
c = 55.523γ = 90
Software Package:
Software NamePurpose
SCALAdata scaling
PHASERphasing
REFMACrefinement
PDB_EXTRACTdata extraction
Blu-Icedata collection
CrystalCleardata reduction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-01-08
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Derived calculations, Version format compliance