4J1S

Crystal structure of a ketoreductase domain from the bacillaene assembly line


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.01 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.235 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structural and functional studies of a trans-acyltransferase polyketide assembly line enzyme that catalyzes stereoselective alpha- and beta-ketoreduction.

Piasecki, S.K.Zheng, J.Axelrod, A.J.E Detelich, M.Keatinge-Clay, A.T.

(2014) Proteins 82: 2067-2077

  • DOI: 10.1002/prot.24561
  • Primary Citation of Related Structures:  4J1Q

  • PubMed Abstract: 
  • While the cis-acyltransferase modular polyketide synthase assembly lines have largely been structurally dissected, enzymes from within the recently discovered trans-acyltransferase polyketide synthase assembly lines are just starting to be observed c ...

    While the cis-acyltransferase modular polyketide synthase assembly lines have largely been structurally dissected, enzymes from within the recently discovered trans-acyltransferase polyketide synthase assembly lines are just starting to be observed crystallographically. Here we examine the ketoreductase (KR) from the first polyketide synthase module of the bacillaene nonribosomal peptide synthetase/polyketide synthase at 2.35-Å resolution. This KR naturally reduces both α- and β-keto groups and is the only KR known to do so during the biosynthesis of a polyketide. The isolated KR not only reduced an N-acetylcysteamine-bound β-keto substrate to a D-β-hydroxy product, but also an N-acetylcysteamine-bound α-keto substrate to an L-α-hydroxy product. That the substrates must enter the active site from opposite directions to generate these stereochemistries suggests that the acyl-phosphopantetheine moiety is capable of accessing very different conformations despite being anchored to a serine residue of a docked acyl carrier protein. The features enabling stereocontrolled α-ketoreduction may not be extensive since a KR that naturally reduces a β-keto group within a cis-acyltransferase polyketide synthase was identified that performs a completely stereoselective reduction of the same α-keto substrate to generate the D-α-hydroxy product. A sequence analysis of trans-acyltransferase KRs reveals that a single residue, rather than a three-residue motif found in cis-acyltransferase KRs, is predictive of the orientation of the resulting β-hydroxyl group.


    Organizational Affiliation

    Institute for Cellular and Molecular Biology, The University of Texas at Austin, Texas, 78712.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Polyketide synthase PksJ
A
464Bacillus subtilis (strain 168)Gene Names: pksJ (pksK)
Find proteins for P40806 (Bacillus subtilis (strain 168))
Go to UniProtKB:  P40806
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.01 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.235 
  • Space Group: P 61
Unit Cell:
Length (Å)Angle (°)
a = 59.551α = 90.00
b = 59.551β = 90.00
c = 221.084γ = 120.00
Software Package:
Software NamePurpose
PHASESphasing
HKL-2000data scaling
REFMACrefinement
HKL-2000data reduction
HKL-2000data collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-03-19
    Type: Initial release
  • Version 1.1: 2014-03-26
    Type: Database references
  • Version 1.2: 2014-08-13
    Type: Database references
  • Version 1.3: 2014-09-03
    Type: Database references