3RI6

A Novel Mechanism of Sulfur Transfer Catalyzed by O-Acetylhomoserine Sulfhydrylase in Methionine Biosynthetic Pathway of Wolinella succinogenes


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.225 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

A novel mechanism of sulfur transfer catalyzed by O-acetylhomoserine sulfhydrylase in the methionine-biosynthetic pathway of Wolinella succinogenes.

Tran, T.H.Krishnamoorthy, K.Begley, T.P.Ealick, S.E.

(2011) Acta Crystallogr.,Sect.D 67: 831-838

  • DOI: 10.1107/S0907444911028010

  • PubMed Abstract: 
  • O-Acetylhomoserine sulfhydrylase (OAHS) is a pyridoxal 5'-phosphate (PLP) dependent sulfide-utilizing enzyme in the L-cysteine and L-methionine biosynthetic pathways of various enteric bacteria and fungi. OAHS catalyzes the conversion of O-acetylhomo ...

    O-Acetylhomoserine sulfhydrylase (OAHS) is a pyridoxal 5'-phosphate (PLP) dependent sulfide-utilizing enzyme in the L-cysteine and L-methionine biosynthetic pathways of various enteric bacteria and fungi. OAHS catalyzes the conversion of O-acetylhomoserine to homocysteine using sulfide in a process known as direct sulfhydrylation. However, the source of the sulfur has not been identified and no structures of OAHS have been reported in the literature. Here, the crystal structure of Wolinella succinogenes OAHS (MetY) determined at 2.2 Å resolution is reported. MetY crystallized in space group C2 with two monomers in the asymmetric unit. Size-exclusion chromatography, dynamic light scattering and crystal packing indicate that the biological unit is a tetramer in solution. This is further supported by the crystal structure, in which a tetramer is formed using a combination of noncrystallographic and crystallographic twofold axes. A search for structurally homologous proteins revealed that MetY has the same fold as cystathionine γ-lyase and methionine γ-lyase. The active sites of these enzymes, which are also PLP-dependent, share a high degree of structural similarity, suggesting that MetY belongs to the γ-elimination subclass of the Cys/Met metabolism PLP-dependent family of enzymes. The structure of MetY, together with biochemical data, provides insight into the mechanism of sulfur transfer to a small molecule via a protein thiocarboxylate intermediate.


    Organizational Affiliation

    Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-1301, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
O-ACETYLHOMOSERINE SULFHYDRYLASE
A, B
430Wolinella succinogenes (strain ATCC 29543 / DSM 1740 / LMG 7466 / NCTC 11488 / FDC 602W)Mutation(s): 0 
Find proteins for Q7M9C8 (Wolinella succinogenes (strain ATCC 29543 / DSM 1740 / LMG 7466 / NCTC 11488 / FDC 602W))
Go to UniProtKB:  Q7M9C8
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.225 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 161.800α = 90.00
b = 62.500β = 120.50
c = 91.600γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
CCP4phasing
DENZOdata reduction
HKL-2000data reduction
REFMACrefinement
PDB_EXTRACTdata extraction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-08-17
    Type: Initial release
  • Version 1.1: 2011-09-28
    Type: Database references, Derived calculations
  • Version 1.2: 2017-02-08
    Type: Other
  • Version 1.3: 2017-11-08
    Type: Refinement description