1XRK

Crystal structure of a mutant bleomycin binding protein from Streptoalloteichus hindustanus displaying increased thermostability


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.174 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Engineering a selectable marker for hyperthermophiles

Brouns, S.J.J.Wu, H.Akerboom, J.Turnbull, A.P.de Vos, W.M.van der Oost, J.

(2005) J.Biol.Chem. 280: 11422-11431

  • DOI: 10.1074/jbc.M413623200

  • PubMed Abstract: 
  • Limited thermostability of antibiotic resistance markers has restricted genetic research in the field of extremely thermophilic Archaea and bacteria. In this study, we used directed evolution and selection in the thermophilic bacterium Thermus thermo ...

    Limited thermostability of antibiotic resistance markers has restricted genetic research in the field of extremely thermophilic Archaea and bacteria. In this study, we used directed evolution and selection in the thermophilic bacterium Thermus thermophilus HB27 to find thermostable variants of a bleomycin-binding protein from the mesophilic bacterium Streptoalloteichus hindustanus. In a single selection round, we identified eight clones bearing five types of double mutated genes that provided T. thermophilus transformants with bleomycin resistance at 77 degrees C, while the wild-type gene could only do so up to 65 degrees C. Only six different amino acid positions were altered, three of which were glycine residues. All variant proteins were produced in Escherichia coli and analyzed biochemically for thermal stability and functionality at high temperature. A synthetic mutant resistance gene with low GC content was designed that combined four substitutions. The encoded protein showed up to 17 degrees C increased thermostability and unfolded at 85 degrees C in the absence of bleomycin, whereas in its presence the protein unfolded at 100 degrees C. Despite these highly thermophilic properties, this mutant was still able to function normally at mesophilic temperatures in vivo. The mutant protein was co-crystallized with bleomycin, and the structure of the binary complex was determined to a resolution of 1.5 A. Detailed structural analysis revealed possible molecular mechanisms of thermostabilization and enhanced antibiotic binding, which included the introduction of an intersubunit hydrogen bond network, improved hydrophobic packing of surface indentations, reduction of loop flexibility, and alpha-helix stabilization. The potential applicability of the thermostable selection marker is discussed.


    Organizational Affiliation

    Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Hesselink van Suchtelenweg 4, 6703 CT Wageningen, The Netherlands. stan.brouns@wur.nl




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Bleomycin resistance protein
A, B
124Streptoalloteichus hindustanusMutation(s): 4 
Gene Names: ble
Find proteins for P17493 (Streptoalloteichus hindustanus)
Go to UniProtKB:  P17493
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

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

Download SDF File 
Download CCD File 
A, B
BLEOMYCIN A2
N1-[3-(DIMETHYLSULFONIO)-PROPYL]BLEOMYCINAMIDE
C55 H85 N17 O21 S3
ZGCQRJQBETWECF-UAPAGMARSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.174 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 43.983α = 90.00
b = 66.617β = 117.43
c = 47.179γ = 90.00
Software Package:
Software NamePurpose
MOLREPphasing
REFMACrefinement
SCALEPACKdata scaling
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-01-11
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance