2CH6

Crystal structure of human N-acetylglucosamine kinase in complex with ADP and glucose


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.72 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.227 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structures of Human N-Acetylglucosamine Kinase in Two Complexes with N-Acetylglucosamine and with Adp/Glucose: Insights Into Substrate Specificity and Regulation.

Weihofen, W.A.Berger, M.Chen, H.Saenger, W.Hinderlich, S.

(2006) J.Mol.Biol. 364: 388

  • DOI: 10.1016/j.jmb.2006.08.085
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • N-Acetylglucosamine (GlcNAc), a major component of complex carbohydrates, is synthesized de novo or salvaged from lysosomally degraded glycoconjugates and from nutritional sources. The salvage pathway requires that GlcNAc kinase converts GlcNAc to Gl ...

    N-Acetylglucosamine (GlcNAc), a major component of complex carbohydrates, is synthesized de novo or salvaged from lysosomally degraded glycoconjugates and from nutritional sources. The salvage pathway requires that GlcNAc kinase converts GlcNAc to GlcNAc-6-phosphate, a component utilized in UDP-GlcNAc biosynthesis or energy metabolism. GlcNAc kinase belongs to the sugar kinase/Hsp70/actin superfamily that catalyze phosphoryl transfer from ATP to their respective substrates, and in most cases catalysis is associated with a large conformational change in which the N-terminal small and C-terminal large domains enclose the substrates. Here we report two crystal structures of homodimeric human GlcNAc kinase, one in complex with GlcNAc and the other in complex with ADP and glucose. The active site of GlcNAc kinase is located in a deep cleft between the two domains of the V-shaped monomer. The enzyme adopts a "closed" configuration in the GlcNAc-bound complex and GlcNAc interacts with residues of both domains. In addition, the N-acetyl methyl group contacts residues of the other monomer in the homodimer, a unique feature compared to other members of the sugar kinase/Hsp70/actin superfamily. This contrasts an "open" configuration in the ADP/glucose-bound structure, where glucose cannot form these interactions, explaining its low binding affinity for GlcNAc kinase. Our results support functional implications derived from apo crystal structures of GlcNAc kinases from Chromobacter violaceum and Porphyromonas gingivalis and show that Tyr205, which is phosphorylated in thrombin-activated platelets, lines the GlcNAc binding pocket. This suggests that phosphorylation of Tyr205 may modulate GlcNAc kinase activity and/or specificity.


    Organizational Affiliation

    Freie Universität Berlin, Institut für Chemie und Biochemie-Kristallographie, Takustrasse 6, 14195 Berlin-Dahlem, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
N-ACETYL-D-GLUCOSAMINE KINASE
A, B, C, D
344Homo sapiensMutation(s): 0 
Gene Names: NAGK
EC: 2.7.1.59
Find proteins for Q9UJ70 (Homo sapiens)
Go to Gene View: NAGK
Go to UniProtKB:  Q9UJ70
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ADP
Query on ADP

Download SDF File 
Download CCD File 
A, B, C, D
ADENOSINE-5'-DIPHOSPHATE
C10 H15 N5 O10 P2
XTWYTFMLZFPYCI-KQYNXXCUSA-N
 Ligand Interaction
GLC
Query on GLC

Download SDF File 
Download CCD File 
A, B, C, D
ALPHA-D-GLUCOSE
C6 H12 O6
WQZGKKKJIJFFOK-DVKNGEFBSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.72 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.227 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 135.710α = 90.00
b = 101.992β = 90.00
c = 110.181γ = 90.00
Software Package:
Software NamePurpose
HKL2MAPphasing
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-09-18
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Refinement description, Version format compliance