2P66

Human DNA Polymerase beta complexed with tetrahydrofuran (abasic site) containing DNA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.280 
  • R-Value Work: 0.217 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural insight into the DNA Polymerase beta deoxyribose phosphate lyase mechanism

Prasad, R.Batra, V.K.Yang, X.-P.Krahn, J.M.Pedersen, L.C.Beard, W.A.Wilson, S.H.

(2005) DNA REPAIR 4: 1347-1357

  • DOI: 10.1016/j.dnarep.2005.08.009

  • PubMed Abstract: 
  • A large number of biochemical and genetic studies have demonstrated the involvement of DNA polymerase beta (Pol beta) in mammalian base excision repair (BER). Pol beta participates in BER sub-pathways by contributing gap filling DNA synthesis and lya ...

    A large number of biochemical and genetic studies have demonstrated the involvement of DNA polymerase beta (Pol beta) in mammalian base excision repair (BER). Pol beta participates in BER sub-pathways by contributing gap filling DNA synthesis and lyase removal of the 5'-deoxyribose phosphate (dRP) group from the cleaved abasic site. To better understand the mechanism of the dRP lyase reaction at an atomic level, we determined a crystal structure of Pol beta complexed with 5'-phosphorylated abasic sugar analogs in nicked DNA. This DNA ligand represents a potential BER intermediate. The crystal structure reveals that the dRP group is bound in a non-catalytic binding site. The catalytic nucleophile in the dRP lyase reaction, Lys72, and all other potential secondary nucleophiles, are too far away to participate in nucleophilic attack on the C1' of the sugar. An approximate model of the dRP group in the expected catalytic binding site suggests that a rotation of 120 degrees about the dRP 3'-phosphate is required to position the epsilon-amino Lys72 close to the dRP C1'. This model also suggests that several other side chains are in position to facilitate the beta-elimination reaction. From results of mutational analysis of key residues in the dRP lyase active site, it appears that the substrate dRP can be stabilized in the observed non-catalytic binding conformation, hindering dRP lyase activity.


    Organizational Affiliation

    Laboratory of Structural Biology, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 4
MoleculeChainsSequence LengthOrganismDetails
DNA polymerase beta
A
335Homo sapiensMutation(s): 0 
Gene Names: POLB
EC: 2.7.7.7, 4.2.99.-
Find proteins for P06746 (Homo sapiens)
Go to Gene View: POLB
Go to UniProtKB:  P06746
Entity ID: 1
MoleculeChainsLengthOrganism
DNA (5'-D(*CP*CP*GP*AP*CP*AP*GP*CP*GP*CP*AP*TP*CP*AP*GP*C)-3')B16N/A
Entity ID: 2
MoleculeChainsLengthOrganism
DNA (5'-D(*GP*CP*TP*GP*AP*TP*GP*CP*GP*CP*C)-3')C11N/A
Entity ID: 3
MoleculeChainsLengthOrganism
DNA (5'-D(P*(3DR)P*GP*TP*CP*GP*G)-3')D6N/A
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
NA
Query on NA

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Download CCD File 
A, C
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
3DR
Query on 3DR
D
DNA LINKINGC5 H11 O6 P

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.280 
  • R-Value Work: 0.217 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 55.700α = 90.00
b = 81.100β = 108.60
c = 54.900γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
SCALEPACKdata scaling
CNSphasing
DENZOdata reduction
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-04-10
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance