1G66

ACETYLXYLAN ESTERASE AT 0.90 ANGSTROM RESOLUTION


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.90 Å
  • R-Value Free: 0.132 
  • R-Value Work: 0.107 
  • R-Value Observed: 0.107 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Multiple conformations of catalytic serine and histidine in acetylxylan esterase at 0.90 A.

Ghosh, D.Sawicki, M.Lala, P.Erman, M.Pangborn, W.Eyzaguirre, J.Gutierrez, R.Jornvall, H.Thiel, D.J.

(2001) J Biol Chem 276: 11159-11166

  • DOI: https://doi.org/10.1074/jbc.M008831200
  • Primary Citation of Related Structures:  
    1G66

  • PubMed Abstract: 

    Acetylxylan esterase (AXEII; 207 amino acids) from Penicillium purpurogenum has substrate specificities toward acetate esters of d-xylopyranose residues in xylan and belongs to a new class of alpha/beta hydrolases. The crystal structure of AXEII has been determined by single isomorphous replacement and anomalous scattering, and refined at 0.90- and 1.10-A resolutions with data collected at 85 K and 295 K, respectively. The tertiary structure consists of a doubly wound alpha/beta sandwich, having a central six-stranded parallel beta-sheet flanked by two parallel alpha-helices on each side. The catalytic residues Ser(90), His(187), and Asp(175) are located at the C-terminal end of the sheet, an exposed region of the molecule. The serine and histidine side chains in the 295 K structure show the frequently observed conformations in which Ser(90) is trans and the hydroxyl group is in the plane of the imidazole ring of His(187). However, the structure at 85 K displays an additional conformation in which Ser(90) side-chain hydroxyl is away from the plane of the imidazole ring of His(187). The His(187) side chain forms a hydrogen bond with a sulfate ion and adopts an altered conformation. The only other known hydrolase that has a similar tertiary structure is Fusarium solani cutinase. The exposed nature of the catalytic triad suggests that AXEII is a pure esterase, i.e. an alpha/beta hydrolase with specificity for nonlipidic polar substrates.


  • Organizational Affiliation

    Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203, USA. ghosh@hwi.buffalo.edu


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
ACETYL XYLAN ESTERASE II207Talaromyces purpureogenusMutation(s): 0 
EC: 3.1.1.6
UniProt
Find proteins for O59893 (Talaromyces purpureogenus)
Explore O59893 
Go to UniProtKB:  O59893
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO59893
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.90 Å
  • R-Value Free: 0.132 
  • R-Value Work: 0.107 
  • R-Value Observed: 0.107 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 34.541α = 90
b = 59.898β = 90
c = 71.392γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
PHASESphasing
SHELXL-97refinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2001-01-17
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Non-polymer description, Version format compliance