2CFC

structural basis for stereo selectivity in the (R)- and (S)- hydroxypropylethane thiosulfonate dehydrogenases


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.197 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structural Basis for Stereoselectivity in the (R)-and (S)-Hydroxypropylthioethanesulfonate Dehydrogenases.

Krishnakumar, A.M.Nocek, B.P.Clark, D.D.Ensign, S.A.Peters, J.W.

(2006) Biochemistry 45: 8831

  • DOI: https://doi.org/10.1021/bi0603569
  • Primary Citation of Related Structures:  
    2CFC

  • PubMed Abstract: 

    Epoxide metabolism in Xanthobacter autotrophicus Py2 results in the conversion of epoxypropane to acetoacetate. Epoxide metabolism is initiated by the nucleophilic addition of coenzyme M to the (R)- and (S)-enantiomers of epoxypropane which forms the respective enantiomers of 2-hydroxypropyl-coenyme M. The (R)- and (S)-enantiomers of 2-hydroxypropyl coenzyme are oxidized to the achiral product 2-ketopropyl-CoM by two stereoselective dehydrogenases. The dehydrogenases catalyzing these reactions, termed (R)-hydroxypropyl-coenzyme M dehydrogenase (R-HPCDH) and (S)-hydroxypropyl-coenzyme M dehydrogenase (S-HPCDH), are NAD(+)-dependent enzymes belonging to the short chain dehydrogenase/reductase (SDR) family of enzymes. In this study, the crystal structure of R-HPCDH cocrystallized in the presence of (S)-hydroxypropyl-coenzyme M has been determined using X-ray diffraction methods and refined to 1.8 A resolution. The structure of R-HPCDH is tetrameric and stabilized by the interaction of the terminal carboxylates of each subunit with divalent metal ions. The structure of the presumed product-bound state reveals that binding interactions between the negatively charged oxygen atoms of the sulfonate moiety have striking similarities to sulfonate interactions observed in the previously determined structure of 2-ketopropyl-CoM oxidoreductase/carboxylase, highlighting the utility of coenzyme M as a carrier molecule in the pathway. The key elements of the aforementioned interactions are electrostatic interactions between the sulfonate oxygen atoms and two arginine residues (R152 and R196) of R-HPCDH. The comparison of the structure of R-HPCDH with a homology model of S-HPCDH provides a structural basis for a mechanism of substrate specificity in which the binding of the substrate sulfonate moiety at distinct sites on each stereoselective enzyme directs the orientation of the appropriate substrate enantiomer for hydride abstraction.


  • Organizational Affiliation

    Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
2-(R)-HYDROXYPROPYL-COM DEHYDROGENASE
A, B, C, D
250Xanthobacter autotrophicus Py2Mutation(s): 0 
EC: 1.1.1.268
UniProt
Find proteins for Q56840 (Xanthobacter autotrophicus (strain ATCC BAA-1158 / Py2))
Explore Q56840 
Go to UniProtKB:  Q56840
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ56840
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.197 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 64.441α = 90
b = 110.28β = 93.88
c = 68.981γ = 90
Software Package:
Software NamePurpose
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
SOLVEphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-07-26
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-05-08
    Changes: Data collection, Database references