Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 33.27 kDa 
• Atom Count: 2390 
• Modelled Residue Count: 298 
• Deposited Residue Count: 298 
• Unique protein chains: 1

2WCU

Crystal structure of mammalian FucU

• PDB DOI: 10.2210/pdb2WCU/pdb

• Classification: ISOMERASE
• Organism(s): Mus musculus
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2009-03-17 Released: 2009-11-10 
• Deposition Author(s): Lee, K.-H., Kim, M.-S., Suh, H.-Y., Ku, B., Song, Y.-L., Oh, B.-H.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.206 
• R-Value Work: 0.190 
• R-Value Observed: 0.190 

Literature

Crystal Structures and Enzyme Mechanism of a Dual Fucose Mutarotase/Ribose Pyranase

Lee, K.-H., Ryu, K.-S., Kim, M.-S., Suh, H.-Y., Ku, B., Song, Y.-L., Ko, S., Lee, W., Oh, B.-H.

(2009) J Mol Biol 391: 178

• PubMed: 19524593 
• DOI: 10.1016/j.jmb.2009.06.022
• Primary Citation of Related Structures:  
  2WCU, 2WCV


• PubMed Abstract: 
  

Escherichia coli FucU (Fucose Unknown) is a dual fucose mutarotase and ribose pyranase, which shares 44% sequence identity with its human counterpart. Herein, we report the structures of E. coli FucU and mouse FucU bound to L-fucose and delineate the catalytic mechanisms underlying the interconversion between stereoisomers of fucose and ribose. E. coli FucU forms a decameric toroid with each active site formed by two adjacent subunits. While one subunit provides most of the fucose-interacting residues including a catalytic tyrosine residue, the other subunit provides a catalytic His-Asp dyad. This active-site feature is critical not only for the mutarotase activity toward L-fucose but also for the pyranase activity toward D-ribose. Structural and biochemical analyses pointed that mouse FucU assembles into four different oligomeric forms, among which the smallest homodimeric form is most abundant and would be the predominant species under physiological conditions. This homodimer has two fucose-binding sites that are devoid of the His-Asp dyad and catalytically inactive, indicating that the mutarotase and the pyranase activities appear dispensable in vertebrates. The defective assembly of the mouse FucU homodimer into the decameric form is due to an insertion of two residues at the N-terminal extreme, which is a common aspect of all the known vertebrate FucU proteins. Therefore, vertebrate FucU appears to serve for as yet unknown function through the quaternary structural alteration.

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Organizational Affiliation: 

Center for Biomolecular Recognition, Division of Molecular and Life Sciences, Pohang University of Science and Technology, Pohang, Kyungbuk, Korea.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN FUCU HOMOLOG	A, B	149	Mus musculus	Mutation(s): 0  Gene Names: Fuom, Le51 EC: 5.1.3 (PDB Primary Data), 5.1.3.29 (UniProt)
UniProt
Find proteins for Q8R2K1 (Mus musculus) Explore Q8R2K1  Go to UniProtKB:  Q8R2K1

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
FUC	C [auth A], D [auth B]	alpha-L-fucopyranose C6 H12 O5 SHZGCJCMOBCMKK-SXUWKVJYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.206 
• R-Value Work: 0.190 
• R-Value Observed: 0.190 
• Space Group: P 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 38.95	α = 76.22
b = 47.444	β = 72.25
c = 55.55	γ = 81.96

Software Package:

Software Name	Purpose
CNS	refinement
HKL-2000	data reduction
SCALEPACK	data scaling
CCP4	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2009-03-17 
• Released Date: 2009-11-10 
Deposition Author(s): Lee, K.-H., Kim, M.-S., Suh, H.-Y., Ku, B., Song, Y.-L., Oh, B.-H.

Revision History  

• Version 1.0: 2009-11-10
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Data collection, Derived calculations, Other, Structure summary