3RH6

DNA Polymerase Beta Mutant (Y271) with a dideoxy-terminated primer with an incoming ribonucleotide (rCTP)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.048 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.195 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Molecular insights into DNA polymerase deterrents for ribonucleotide insertion.

Cavanaugh, N.A.Beard, W.A.Batra, V.K.Perera, L.Pedersen, L.G.Wilson, S.H.

(2011) J.Biol.Chem. 286: 31650-31660

  • DOI: 10.1074/jbc.M111.253401
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • DNA polymerases can misinsert ribonucleotides that lead to genomic instability. DNA polymerase β discourages ribonucleotide insertion with the backbone carbonyl of Tyr-271; alanine substitution of Tyr-271, but not Phe-272, resulted in a >10-fold loss ...

    DNA polymerases can misinsert ribonucleotides that lead to genomic instability. DNA polymerase β discourages ribonucleotide insertion with the backbone carbonyl of Tyr-271; alanine substitution of Tyr-271, but not Phe-272, resulted in a >10-fold loss in discrimination. The Y271A mutant also inserted ribonucleotides more efficiently than wild type on a variety of ribonucleoside (rNMP)-containing DNA substrates. Substituting Mn(2+) for Mg(2+) decreased sugar discrimination for both wild-type and mutant enzymes primarily by increasing the affinity for rCTP. This facilitated crystallization of ternary substrate complexes of both the wild-type and Y271A mutant enzymes. Crystallographic structures of Y271A- and wild type-substrate complexes indicated that rCTP is well accommodated in the active site but that O2' of rCTP and the carbonyl oxygen of Tyr-271 or Ala-271 are unusually close (∼2.5 and 2.6 Å, respectively). Structure-based modeling indicates that the local energetic cost of positioning these closely spaced oxygens is ∼2.2 kcal/mol for the wild-type enzyme. Because the side chain of Tyr-271 also hydrogen bonds with the primer terminus, loss of this interaction affects its catalytic positioning. Our results support a model where DNA polymerase β utilizes two strategies, steric and geometric, with a single protein residue to deter ribonucleotide insertion.


    Organizational Affiliation

    Laboratory of Structural Biology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709-2233, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
DNA polymerase beta
A
335Homo sapiensMutation(s): 1 
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: 2
MoleculeChainsLengthOrganism
5'-D(*CP*CP*GP*AP*CP*GP*CP*CP*GP*CP*AP*TP*CP*AP*GP*C)-3'T16N/A
Entity ID: 3
MoleculeChainsLengthOrganism
(5'-D(*GP*CP*TP*GP*AP*TP*GP*CP*GP*(DDG))-3')P10N/A
Entity ID: 4
MoleculeChainsLengthOrganism
(5'-D(P*GP*TP*CP*GP*G)-3')D5N/A
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MN
Query on MN

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A, D, T
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
NA
Query on NA

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A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
CL
Query on CL

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A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
CTP
Query on CTP

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Download CCD File 
A
CYTIDINE-5'-TRIPHOSPHATE
C9 H16 N3 O14 P3
PCDQPRRSZKQHHS-XVFCMESISA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
DDG
Query on DDG
P
DNA LINKINGC10 H14 N5 O6 PDG
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.048 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.195 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 51.060α = 90.00
b = 79.810β = 107.68
c = 55.060γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
PHENIXphasing
HKL-2000data scaling
PHENIXmodel building
PHENIXrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-07-06
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2011-07-20
    Type: Database references
  • Version 1.3: 2011-09-21
    Type: Database references