Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 33.06 kDa 
• Atom Count: 2560 
• Residue Count: 296 
• Unique protein chains: 1

2HQQ

Crystal structure of human ketohexokinase complexed to different sugar molecules

• DOI: 10.2210/pdb2HQQ/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2006-07-19 Released: 2007-07-10 
• Deposition Author(s): Trinh, C.H., Asipu, A., Bonthron, D.T., Phillips, S.E.V.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.86 Å
• R-Value Free: 0.234 
• R-Value Work: 0.205 
• R-Value Observed: 0.208 

Literature

Structures of alternatively spliced isoforms of human ketohexokinase.

Trinh, C.H., Asipu, A., Bonthron, D.T., Phillips, S.E.

(2009) Acta Crystallogr D Biol Crystallogr 65: 201-211

• PubMed: 19237742 
• DOI: 10.1107/S0907444908041115
• Primary Citation of Related Structures:  
  2HQQ, 2HW1


• PubMed Abstract: 
  

A molecular understanding of the unique aspects of dietary fructose metabolism may be the key to understanding and controlling the current epidemic of fructose-related obesity, diabetes and related adverse metabolic states in Western populations. Fructose catabolism is initiated by its phosphorylation to fructose 1-phosphate, which is performed by ketohexokinase (KHK). Here, the crystal structures of the two alternatively spliced isoforms of human ketohexokinase, hepatic KHK-C and the peripheral isoform KHK-A, and of the ternary complex of KHK-A with the substrate fructose and AMP-PNP are reported. The structure of the KHK-A ternary complex revealed an active site with both the substrate fructose and the ATP analogue in positions ready for phosphorylation following a reaction mechanism similar to that of the pfkB family of carbohydrate kinases. Hepatic KHK deficiency causes the benign disorder essential fructosuria. The effects of the disease-causing mutations (Gly40Arg and Ala43Thr) have been modelled in the context of the KHK structure.

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Organizational Affiliation: 

Astbury Centre for Structural Molecular Biology, Institute of Molecular and Cellular Biology, University of Leeds, Leeds, England.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Ketohexokinase	A	298	Homo sapiens	Mutation(s): 0  Gene Names: KHK EC: 2.7.1.3
Find proteins for P50053 (Homo sapiens) Explore P50053  Go to UniProtKB:  P50053
NIH Common Fund Data Resources
PHAROS:  P50053 GTEx:  ENSG00000138030

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	A	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.86 Å
• R-Value Free: 0.234 
• R-Value Work: 0.205 
• R-Value Observed: 0.208 
• Space Group: I 2 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 61.26	α = 90
b = 109.619	β = 90
c = 146.29	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction
SCALA	data scaling
SOLVE	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-07-19 
• Released Date: 2007-07-10 
Deposition Author(s): Trinh, C.H., Asipu, A., Bonthron, D.T., Phillips, S.E.V.

Revision History 

• Version 1.0: 2007-07-10
  Type: Initial release
  
• Version 1.1: 2008-05-01
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance