1HKB

CRYSTAL STRUCTURE OF RECOMBINANT HUMAN BRAIN HEXOKINASE TYPE I COMPLEXED WITH GLUCOSE AND GLUCOSE-6-PHOSPHATE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.80 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 

Starting Model: other
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wwPDB Validation   3D Report Full Report


This is version 1.5 of the entry. See complete history


Literature

The mechanism of regulation of hexokinase: new insights from the crystal structure of recombinant human brain hexokinase complexed with glucose and glucose-6-phosphate.

Aleshin, A.E.Zeng, C.Bourenkov, G.P.Bartunik, H.D.Fromm, H.J.Honzatko, R.B.

(1998) Structure 6: 39-50

  • DOI: https://doi.org/10.1016/s0969-2126(98)00006-9
  • Primary Citation of Related Structures:  
    1HKB

  • PubMed Abstract: 

    Hexokinase I is the pacemaker of glycolysis in brain tissue. The type I isozyme exhibits unique regulatory properties in that physiological levels of phosphate relieve potent inhibition by the product, glucose-6-phosphate (Gluc-6-P). The 100 kDa polypeptide chain of hexokinase I consists of a C-terminal (catalytic) domain and an N-terminal (regulatory) domain. Structures of ligated hexokinase I should provide a basis for understanding mechanisms of catalysis and regulation at an atomic level. The complex of human hexokinase I with glucose and Gluc-6-P (determined to 2.8 A resolution) is a dimer with twofold molecular symmetry. The N- and C-terminal domains of one monomer interact with the C- and N-terminal domains, respectively, of the symmetry-related monomer. The two domains of a monomer are connected by a single alpha helix and each have the fold of yeast hexokinase. Salt links between a possible cation-binding loop of the N-terminal domain and a loop of the C-terminal domain may be important to regulation. Each domain binds single glucose and Gluc-6-P molecules in proximity to each other. The 6-phosphoryl group of bound Gluc-6-P at the C-terminal domain occupies the putative binding site for ATP, whereas the 6-phosphoryl group at the N-terminal domain may overlap the binding site for phosphate. The binding synergism of glucose and Gluc-6-P probably arises out of the mutual stabilization of a common (glucose-bound) conformation of hexokinase I. Conformational changes in the N-terminal domain in response to glucose, phosphate, and/or Gluc-6-P may influence the binding of ATP to the C-terminal domain.


  • Organizational Affiliation

    Department of Biochemistry and Biophysics, Iowa State University, Ames 50011, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
D-GLUCOSE 6-PHOSPHOTRANSFERASE
A, B
917Homo sapiensMutation(s): 0 
EC: 2.7.1.1
UniProt & NIH Common Fund Data Resources
Find proteins for P19367 (Homo sapiens)
Explore P19367 
Go to UniProtKB:  P19367
PHAROS:  P19367
GTEx:  ENSG00000156515 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP19367
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
G6P
Query on G6P

Download Ideal Coordinates CCD File 
D [auth A],
F [auth A],
J [auth B],
L [auth B]
6-O-phosphono-alpha-D-glucopyranose
C6 H13 O9 P
NBSCHQHZLSJFNQ-DVKNGEFBSA-N
BGC
Query on BGC

Download Ideal Coordinates CCD File 
C [auth A],
E [auth A],
I [auth B],
K [auth B]
beta-D-glucopyranose
C6 H12 O6
WQZGKKKJIJFFOK-VFUOTHLCSA-N
CA
Query on CA

Download Ideal Coordinates CCD File 
G [auth A],
H [auth A],
M [auth B],
N [auth B]
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.80 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 83α = 90
b = 122β = 92
c = 123γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORrefinement
DENZOdata reduction
SCALEPACKdata scaling
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1998-06-03
    Type: Initial release
  • Version 1.1: 2008-03-03
    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: Advisory, Data collection, Derived calculations, Other, Structure summary
  • Version 1.4: 2024-02-07
    Changes: Data collection, Database references, Structure summary
  • Version 1.5: 2024-04-03
    Changes: Refinement description