1E89

ON THE MECHANISM OF CYANOGENESIS CATALYZED BY HYDROXYNITRILE LYASE FROM MANIHOT ESCULENTA. CRYSTAL STRUCTURE OF ACTIVE SITE MUTANT SER80ALA IN COMPLEX WITH ACETONE CYANOHYDRIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.180 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Mechanistic Aspects of Cyanogenesis from Active-Site Mutant Ser80Ala of Hydroxynitrile Lyase from Manihot Esculenta in Complex with Acetone Cyanohydrin

Lauble, H.Miehlich, B.Foerster, S.Wajant, H.Effenberger, F.

(2001) Protein Sci. 10: 1015

  • DOI: 10.1110/ps.01301
  • Primary Citation of Related Structures:  1E8D

  • PubMed Abstract: 
  • The structure and function of hydroxynitrile lyase from Manihot esculenta (MeHNL) have been analyzed by X-ray crystallography and site-directed mutagenesis. The crystal structure of the MeHNL-S80A mutant enzyme has been refined to an R-factor of 18.0 ...

    The structure and function of hydroxynitrile lyase from Manihot esculenta (MeHNL) have been analyzed by X-ray crystallography and site-directed mutagenesis. The crystal structure of the MeHNL-S80A mutant enzyme has been refined to an R-factor of 18.0% against diffraction data to 2.1-A resolution. The three-dimensional structure of the MeHNL-S80A-acetone cyanohydrin complex was determined at 2.2-A resolution and refined to an R-factor of 18.7%. Thr11 and Cys81 involved in substrate binding have been substituted by Ala in site-directed mutagenesis. The kinetic measurements of these mutant enzymes are presented. Combined with structural data, the results support a mechanism for cyanogenesis in which His236 as a general base abstracts a proton from Ser80, thereby allowing proton transfer from the hydroxyl group of acetone cyanohydrin to Ser80. The His236 imidazolium cation then facilitates the leaving of the nitrile group by proton donating.


    Related Citations: 
    • Structure of Hydroxynitrile Lyase from Manihot Esculenta in Complex with Substrates Acetone and Chloroacetone: Implications for the Mechanism of Cyanogenesis
      Lauble, H.,Foerster, S.,Miehlich, B.,Wajant, H.,Effenberger, F.
      (2001) Acta Crystallogr.,Sect.D 57: 194


    Organizational Affiliation

    Institut für Organische Chemie der Universität Stuttgart, D-70569 Stuttgart, Germany. PeterLauble@t-online.de




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
HYDROXYNITRILE LYASE
A, B
262Manihot esculentaGene Names: HNL
EC: 4.1.2.47
Find proteins for P52705 (Manihot esculenta)
Go to UniProtKB:  P52705
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.180 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 106.180α = 90.00
b = 106.180β = 90.00
c = 188.150γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
DENZOdata reduction
X-PLORphasing
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-08-17
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance