1PV1

Crystal Structure Analysis of Yeast Hypothetical Protein: YJG8_YEAST


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.298 
  • R-Value Work: 0.255 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural characterization and reversal of the natural organophosphate resistance of a D-type esterase, Saccharomyces cerevisiae S-formylglutathione hydrolase.

Legler, P.M.Kumaran, D.Swaminathan, S.Studier, F.W.Millard, C.B.

(2008) Biochemistry 47: 9592-9601

  • DOI: 10.1021/bi8010016
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Saccharomyces cerevisiae expresses a 67.8 kDa homodimeric serine thioesterase, S-formylglutathione hydrolase (SFGH), that is 39.9% identical with human esterase D. Both enzymes possess significant carboxylesterase and S-formylglutathione thioesterase ...

    Saccharomyces cerevisiae expresses a 67.8 kDa homodimeric serine thioesterase, S-formylglutathione hydrolase (SFGH), that is 39.9% identical with human esterase D. Both enzymes possess significant carboxylesterase and S-formylglutathione thioesterase activity but are unusually resistant to organophosphate (OP) inhibitors. We determined the X-ray crystal structure of yeast (y) SFGH to 2.3 A resolution by multiwavelength anomalous dispersion and used the structure to guide site-specific mutagenesis experiments addressing substrate and inhibitor reactivity. Our results demonstrate a steric mechanism of OP resistance mediated by a single indole ring (W197) located in an enzyme "acyl pocket". The W197I substitution enhances ySFGH reactivity with paraoxon by >1000-fold ( k i (W197I) = 16 +/- 2 mM (-1) h (-1)), thereby overcoming natural OP resistance. W197I increases the rate of OP inhibition under pseudo-first-order conditions but does not accelerate OP hydrolysis. The structure of the paraoxon-inhibited W197I variant was determined by molecular replacement (2.2 A); it revealed a stabilized sulfenic acid at Cys60. Wild-type (WT) ySFGH is inhibited by thiol reactive compounds and is sensitive to oxidation; thus, the cysteine sulfenic acid may play a role in the regulation of a "D-type" esterase. The structure of the W197I variant is the first reported cysteine sulfenic acid in a serine esterase. We constructed five Cys60/W197I variants and show that introducing a positive charge near the oxyanion hole, W197I/C60R or W197I/C60K, results in a further enhancement of the rates of phosphorylation with paraoxon ( k i = 42 or 80 mM (-1) h (-1), respectively) but does not affect the dephosphorylation of the enzyme. We also characterized three histidine substitutions near the oxyanion hole, G57H, L58H, and M162H, which significantly decrease esterase activity.


    Organizational Affiliation

    Division of Biochemistry, Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Hypothetical 33.9 kDa esterase in SMC3-MRPL8 intergenic region
A, B, C, D
299Saccharomyces cerevisiae (strain ATCC 204508 / S288c)EC: 3.1.2.12
Find proteins for P40363 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Go to UniProtKB:  P40363
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.298 
  • R-Value Work: 0.255 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 121.366α = 90.00
b = 66.929β = 90.00
c = 171.949γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
MARMADdata reduction
HKL-2000data scaling
HKL-2000data reduction
MARMADdata collection
PHASESphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-11-30
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance