2JBM

QPRTASE STRUCTURE FROM HUMAN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.208 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.177 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural and Kinetic Characterization of Quinolinate Phosphoribosyltransferase (Hqprtase) from Homo Sapiens.

Liu, H.Woznica, K.Catton, G.Crawford, A.Bottinf, N.Naismith, J.H.

(2007) J Mol Biol 373: 755

  • DOI: 10.1016/j.jmb.2007.08.043
  • Primary Citation of Related Structures:  
    2JBM

  • PubMed Abstract: 
  • Human quinolinate phosphoribosyltransferase (EC 2.4.2.19) (hQPRTase) is a member of the type II phosphoribosyltransferase family involved in the catabolism of quinolinic acid (QA). It catalyses the formation of nicotinic acid mononucleotide from quinolinic acid, which involves a phosphoribosyl transfer reaction followed by decarboxylation ...

    Human quinolinate phosphoribosyltransferase (EC 2.4.2.19) (hQPRTase) is a member of the type II phosphoribosyltransferase family involved in the catabolism of quinolinic acid (QA). It catalyses the formation of nicotinic acid mononucleotide from quinolinic acid, which involves a phosphoribosyl transfer reaction followed by decarboxylation. hQPRTase has been implicated in a number of neurological conditions and in order to study it further, we have carried out structural and kinetic studies on recombinant hQPRTase. The structure of the fully active enzyme overexpressed in Escherichia coli was solved using multiwavelength methods to a resolution of 2.0 A. hQPRTase has a alpha/beta barrel fold sharing a similar overall structure with the bacterial QPRTases. The active site of hQPRTase is located at an alpha/beta open sandwich structure that serves as a cup for the alpha/beta barrel of the adjacent subunit with a QA binding site consisting of three arginine residues (R102, R138 and R161) and two lysine residues (K139 and K171). Mutation of these residues affected substrate binding or abolished the enzymatic activity. The kinetics of the human enzyme are different to the bacterial enzymes studied, hQPRTase is inhibited competitively and non-competitively by one of its substrates, 5-phosphoribosylpyrophosphate (PRPP). The human enzyme adopts a hexameric arrangement, which places the active sites in close proximity to each other.


    Organizational Affiliation

    The Centre for Biomolecular Science, The University of St Andrews, North Haugh, St. Andrews KY16 9ST, Scotland.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
NICOTINATE-NUCLEOTIDE PYROPHOSPHORYLASE
A, B, C, D, E, F, G, H
A, B, C, D, E, F, G, H, I, J, K, L
299Homo sapiensMutation(s): 0 
Gene Names: QPRT
EC: 2.4.2.19
Find proteins for Q15274 (Homo sapiens)
Explore Q15274 
Go to UniProtKB:  Q15274
NIH Common Fund Data Resources
PHAROS:  Q15274
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.208 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.177 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 110.925α = 90
b = 179.288β = 90
c = 194.555γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2007-11-13
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance