2CFC

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


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.197 

wwPDB Validation 3D Report Full Report


This is version 1.2 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: 10.1021/bi0603569

  • 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 ...

    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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
2-(R)-HYDROXYPROPYL-COM DEHYDROGENASE
A, B, C, D
250Xanthobacter autotrophicus (strain ATCC BAA-1158 / Py2)Mutation(s): 0 
Gene Names: xecD
EC: 1.1.1.268
Find proteins for Q56840 (Xanthobacter autotrophicus (strain ATCC BAA-1158 / Py2))
Go to UniProtKB:  Q56840
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
KPC
Query on KPC

Download SDF File 
Download CCD File 
A, B, C, D
(2-[2-KETOPROPYLTHIO]ETHANESULFONATE
C5 H10 O4 S2
CRNXHFXAXBWIRH-UHFFFAOYSA-N
 Ligand Interaction
NAD
Query on NAD

Download SDF File 
Download CCD File 
A, B, C, D
NICOTINAMIDE-ADENINE-DINUCLEOTIDE
C21 H27 N7 O14 P2
BAWFJGJZGIEFAR-NNYOXOHSSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.197 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 64.441α = 90.00
b = 110.280β = 93.88
c = 68.981γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
SOLVEphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-07-26
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance