2AEY

Crystal structure of fructan 1-exohydrolase IIa from Cichorium intybus in complex with 2,5 dideoxy-2,5-immino-D-mannitol


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.27 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.217 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Insights into the fine architecture of the active site of chicory fructan 1-exohydrolase: 1-kestose as substrate vs sucrose as inhibitor.

Verhaest, M.Lammens, W.Le Roy, K.De Ranter, C.J.Van Laere, A.Rabijns, A.Van den Ende, W.

(2007) New Phytol 174: 90-100

  • DOI: 10.1111/j.1469-8137.2007.01988.x
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • * Invertases and fructan exohydrolases (FEHs) fulfil important physiological functions in plants. Sucrose is the typical substrate for invertases and bacterial levansucrases but not for plant FEHs, which are usually inhibited by sucrose. * Here we re ...

    * Invertases and fructan exohydrolases (FEHs) fulfil important physiological functions in plants. Sucrose is the typical substrate for invertases and bacterial levansucrases but not for plant FEHs, which are usually inhibited by sucrose. * Here we report on complexes between chicory (Cichorium intybus) 1-FEH IIa with the substrate 1-kestose and the inhibitors sucrose, fructose and 2,5 dideoxy-2,5-imino-D-mannitol. Comparisons with other family GH32 and 68 enzyme-substrate complexes revealed that sucrose can bind as a substrate (invertase/levansucrase) or as an inhibitor (1-FEH IIa). * Sucrose acts as inhibitor because the O2 of the glucose moiety forms an H-linkage with the acid-base catalyst E201, inhibiting catalysis. By contrast, the homologous O3 of the internal fructose in the substrate 1-kestose forms an intramolecular H-linkage and does not interfere with the catalytic process. Mutagenesis showed that W82 and S101 are important for binding sucrose as inhibitor. * The physiological implications of the essential differences in the active sites of FEHs and invertases/levansucrases are discussed. Sucrose-inhibited FEHs show a K(i) (inhibition constant) well below physiological sucrose concentrations and could be rapidly activated under carbon deprivation.


    Organizational Affiliation

    Laboratorium voor Biokristallografie, Faculteit Farmaceutische Wetenschappen, KU Leuven, Herestraat 49, O & N II, bus 822, B-3000 Leuven, Belgium.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
fructan 1-exohydrolase IIa
A
543Cichorium intybusMutation(s): 0 
Gene Names: 1-feh IIa
EC: 3.2.1.80
Find proteins for Q93X60 (Cichorium intybus)
Go to UniProtKB:  Q93X60
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MAN
Query on MAN

Download SDF File 
Download CCD File 
A
ALPHA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-PQMKYFCFSA-N
 Ligand Interaction
DQQ
Query on DQQ

Download SDF File 
Download CCD File 
A
2,5-DIDEOXY-2,5-IMINO-D-MANNITOL
C6 H13 N O4
PFYHYHZGDNWFIF-KVTDHHQDSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.27 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.217 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 138.860α = 90.00
b = 138.860β = 90.00
c = 182.440γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
CNSphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-08-29
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance