2IA6

Bypass of Major Benzopyrene-dG Adduct by Y-Family DNA Polymerase with Unique Structural Gap


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.216 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

A structural gap in Dpo4 supports mutagenic bypass of a major benzo[a]pyrene dG adduct in DNA through template misalignment.

Bauer, J.Xing, G.Yagi, H.Sayer, J.M.Jerina, D.M.Ling, H.

(2007) Proc.Natl.Acad.Sci.Usa 104: 14905-14910

  • DOI: 10.1073/pnas.0700717104
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Erroneous replication of lesions in DNA by DNA polymerases leads to elevated mutagenesis. To understand the molecular basis of DNA damage-induced mutagenesis, we have determined the x-ray structures of the Y-family polymerase, Dpo4, in complex with a ...

    Erroneous replication of lesions in DNA by DNA polymerases leads to elevated mutagenesis. To understand the molecular basis of DNA damage-induced mutagenesis, we have determined the x-ray structures of the Y-family polymerase, Dpo4, in complex with a DNA substrate containing a bulky DNA lesion and incoming nucleotides. The DNA lesion is derived from an environmentally widespread carcinogenic polycyclic aromatic hydrocarbon, benzo[a]pyrene (BP). The potent carcinogen BP is metabolized to diol epoxides that form covalent adducts with cellular DNA. In the present study, the major BP diol epoxide adduct in DNA, BP-N(2)-deoxyguanosine (BP-dG), was placed at a template-primer junction. Three ternary complexes reveal replication blockage, extension past a mismatched lesion, and a -1 frameshift mutation. In the productive structures, the bulky adduct is flipped/looped out of the DNA helix into a structural gap between the little finger and core domains. Sequestering of the hydrophobic BP adduct in this new substrate-binding site permits the DNA to exhibit normal geometry for primer extension. Extrusion of the lesion by template misalignment allows the base 5' to the adduct to serve as the template, resulting in a -1 frameshift. Subsequent strand realignment produces a mismatched base opposite the lesion. These structural observations, in combination with replication and mutagenesis data, suggest a model in which the additional substrate-binding site stabilizes the extrahelical nucleotide for lesion bypass and generation of base substitutions and -1 frameshift mutations.


    Organizational Affiliation

    Department of Biochemistry, University of Western Ontario, London, ON, Canada N6A 5C1.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
DNA polymerase IV
A, B
352Sulfolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2)Mutation(s): 0 
Gene Names: dbh (dpo4)
EC: 2.7.7.7
Find proteins for Q97W02 (Sulfolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2))
Go to UniProtKB:  Q97W02
Entity ID: 2
MoleculeChainsLengthOrganism
5'-D(*GP*GP*GP*GP*GP*AP*AP*GP*GP*AP*TP*TP*A)-3'C,E13N/A
Entity ID: 3
MoleculeChainsLengthOrganism
5'-D(*TP*CP*AP*TP*GP*AP*AP*TP*CP*CP*TP*TP*CP*CP*CP*CP*C)-3'D,F17N/A
Small Molecules
Ligands 6 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

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A, B
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
PO4
Query on PO4

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A
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
GOL
Query on GOL

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B, E, F
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

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A, B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
EDO
Query on EDO

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C, F
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
BAP
Query on BAP

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D, F
1,2,3-TRIHYDROXY-1,2,3,4-TETRAHYDROBENZO[A]PYRENE
C20 H16 O3
GFANZDFKCCJYRF-NSISKUIASA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.216 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 98.217α = 90.00
b = 102.580β = 90.00
c = 106.147γ = 90.00
Software Package:
Software NamePurpose
ADSCdata collection
HKL-2000data scaling
HKL-2000data reduction
CNSphasing
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-09-11
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Non-polymer description, Version format compliance