4F5M

Wild-Type E. coli Aspartate Aminotransferase: A Template For The Interconversion of Substrate Specificity and Activity To Tyrosine Aminotransferase By The JANUS Algorithm.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.65 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.177 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Janus: prediction and ranking of mutations required for functional interconversion of enzymes.

Addington, T.A.Mertz, R.W.Siegel, J.B.Thompson, J.M.Fisher, A.J.Filkov, V.Fleischman, N.M.Suen, A.A.Zhang, C.Toney, M.D.

(2013) J Mol Biol 425: 1378-1389

  • DOI: https://doi.org/10.1016/j.jmb.2013.01.034
  • Primary Citation of Related Structures:  
    4F5F, 4F5G, 4F5H, 4F5I, 4F5J, 4F5K, 4F5M

  • PubMed Abstract: 

    Identification of residues responsible for functional specificity in enzymes is a challenging and important problem in protein chemistry. Active-site residues are generally easy to identify, but residues outside the active site are also important to catalysis and their identities and roles are more difficult to determine. We report a method based on analysis of multiple sequence alignments, embodied in our program Janus, for predicting mutations required to interconvert structurally related but functionally distinct enzymes. Conversion of aspartate aminotransferase into tyrosine aminotransferase is demonstrated and compared to previous efforts. Incorporation of 35 predicted mutations resulted in an enzyme with the desired substrate specificity but low catalytic activity. A single round of DNA back-shuffling with wild-type aspartate aminotransferase on this variant generated mutants with tyrosine aminotransferase activities better than those previously realized from rational design or directed evolution. Methods such as this, coupled with computational modeling, may prove invaluable in furthering our understanding of enzyme catalysis and engineering.


  • Organizational Affiliation

    Department of Chemistry, University of California, Davis, CA 95616, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Aspartate aminotransferase
A, B
406Escherichia coli K-12Mutation(s): 0 
Gene Names: AATaspCb0928JW0911
EC: 2.6.1.1
UniProt
Find proteins for P00509 (Escherichia coli (strain K12))
Explore P00509 
Go to UniProtKB:  P00509
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00509
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.65 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.177 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 58.299α = 90
b = 108.938β = 90
c = 144.234γ = 90
Software Package:
Software NamePurpose
PROTEUM PLUSdata collection
PHASERphasing
PHENIXrefinement
PROTEUM PLUSdata reduction
PROTEUM PLUSdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-02-13
    Type: Initial release
  • Version 1.1: 2013-02-20
    Changes: Refinement description
  • Version 1.2: 2013-02-27
    Changes: Database references
  • Version 1.3: 2013-04-24
    Changes: Database references