3KOF

Crystal structure of the double mutant F178Y/R181E of E.coli transaldolase B


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.203 
  • R-Value Observed: 0.205 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Redesigning the Active Site of Transaldolase TalB from Escherichia coli: New Variants with Improved Affinity towards Nonphosphorylated Substrates.

Schneider, S.Gutierrez, M.Sandalova, T.Schneider, G.Clapes, P.Sprenger, G.A.Samland, A.K.

(2010) Chembiochem 11: 681-690

  • DOI: https://doi.org/10.1002/cbic.200900720
  • Primary Citation of Related Structures:  
    3KOF

  • PubMed Abstract: 

    Recently, we reported on a transaldolase B variant (TalB F178Y) that is able to use dihydroxyacetone (DHA) as donor in aldol reactions. In a second round of protein engineering, we aimed at improving the affinity of this variant towards nonphosphorylated acceptor aldehydes, that is, glyceraldehyde (GA). The anion binding site was identified in the X-ray structure of TalB F178Y where a sulfate ion from the buffer was bound in the active site. Therefore, we performed site-directed saturation mutagenesis at three residues forming the putative phosphate binding site, Arg181, Ser226 and Arg228. The focused libraries were screened for the formation of D-fructose from DHA and d,l-GA by using an adjusted colour assay. The best results with respect to the synthesis of D-fructose were achieved with the TalB F178Y/R181E variant, which exhibited an at least fivefold increase in affinity towards d,l-GA (K(M)=24 mM). We demonstrated that this double mutant can use D-GA, glycolaldehyde and the L-isomer, L-GA, as acceptor substrates. This resulted in preparative synthesis of D-fructose, D-xylulose and L-sorbose when DHA was used as donor. Hence, we engineered a DHA-dependent aldolase that can synthesise the formation of polyhydroxylated compounds from simple and cheap substrates at preparative scale.


  • Organizational Affiliation

    Institute of Microbiology, Universität Stuttgart, Allmandring 31, Germany.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Transaldolase B
A, B
337Escherichia coli K-12Mutation(s): 3 
Gene Names: talByaaKb0008JW0007
EC: 2.2.1.2
UniProt
Find proteins for P0A870 (Escherichia coli (strain K12))
Explore P0A870 
Go to UniProtKB:  P0A870
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0A870
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.203 
  • R-Value Observed: 0.205 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 66.404α = 90
b = 86.397β = 90
c = 130.745γ = 90
Software Package:
Software NamePurpose
ADSCdata collection
MOLREPphasing
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2010-02-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2021-10-13
    Changes: Database references, Derived calculations
  • Version 1.3: 2023-09-06
    Changes: Data collection, Refinement description