3VC3

Crystal structure of beta-cyanoalanine synthase K95A mutant in soybean


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.77 Å
  • R-Value Free: 0.202 
  • R-Value Work: 0.170 
  • R-Value Observed: 0.170 

wwPDB Validation   3D Report Full Report


This is version 1.0 of the entry. See complete history


Literature

Structure of Soybean beta-Cyanoalanine Synthase and the Molecular Basis for Cyanide Detoxification in Plants.

Yi, H.Juergens, M.Jez, J.M.

(2012) Plant Cell 24: 2696-2706

  • DOI: 10.1105/tpc.112.098954
  • Primary Citation of Related Structures:  
    3VC3, 3VBE

  • PubMed Abstract: 
  • Plants produce cyanide (CN-) during ethylene biosynthesis in the mitochondria and require β-cyanoalanine synthase (CAS) for CN- detoxification. Recent studies show that CAS is a member of the β-substituted alanine synthase (BSAS) family, which also includes the Cys biosynthesis enzyme O-acetylserine sulfhydrylase (OASS), but how the BSAS evolved distinct metabolic functions is not understood ...

    Plants produce cyanide (CN-) during ethylene biosynthesis in the mitochondria and require β-cyanoalanine synthase (CAS) for CN- detoxification. Recent studies show that CAS is a member of the β-substituted alanine synthase (BSAS) family, which also includes the Cys biosynthesis enzyme O-acetylserine sulfhydrylase (OASS), but how the BSAS evolved distinct metabolic functions is not understood. Here we show that soybean (Glycine max) CAS and OASS form α-aminoacrylate reaction intermediates from Cys and O-acetylserine, respectively. To understand the molecular evolution of CAS and OASS in the BSAS enzyme family, the crystal structures of Gm-CAS and the Gm-CAS K95A mutant with a linked pyridoxal phosphate (PLP)-Cys molecule in the active site were determined. These structures establish a common fold for the plant BSAS family and reveal a substrate-induced conformational change that encloses the active site for catalysis. Comparison of CAS and OASS identified residues that covary in the PLP binding site. The Gm-OASS T81M, S181M, and T185S mutants altered the ratio of OASS:CAS activity but did not convert substrate preference to that of a CAS. Generation of a triple mutant Gm-OASS successfully switched reaction chemistry to that of a CAS. This study provides new molecular insight into the evolution of diverse enzyme functions across the BSAS family in plants.


    Organizational Affiliation

    Department of Biology, Washington University, St. Louis, Missouri 63130, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
beta-cyanoalnine synthaseA, B, C, D, E, F344Glycine maxMutation(s): 0 
Gene Names: GLYMA09G39390OAS-TL3GLYMA_09G258000
EC: 2.5.1.47
UniProt
Find proteins for I1L6I6 (Glycine max)
Explore I1L6I6 
Go to UniProtKB:  I1L6I6
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
C6P
Query on C6P

Download Ideal Coordinates CCD File 
G [auth A], H [auth B], I [auth C], J [auth D], K [auth E], L [auth F]N-({3-HYDROXY-2-METHYL-5-[(PHOSPHONOOXY)METHYL]PYRIDIN-4-YL}METHYL)-L-CYSTEINE
C11 H17 N2 O7 P S
FPVGQJHHLSVHOT-VIFPVBQESA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.77 Å
  • R-Value Free: 0.202 
  • R-Value Work: 0.170 
  • R-Value Observed: 0.170 
  • Space Group: P 2 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 71.092α = 90
b = 154.325β = 90
c = 198.328γ = 90
Software Package:
Software NamePurpose
SCALEPACKdata scaling
PHENIXrefinement
PDB_EXTRACTdata extraction
HKL-3000data collection

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

  • Deposited Date: 2012-01-03 
  • Released Date: 2012-09-12 
  • Deposition Author(s): Yi, H., Jez, J.M.

Revision History  (Full details and data files)

  • Version 1.0: 2012-09-12
    Type: Initial release