1FXX

THE STRUCTURE OF EXONUCLEASE I SUGGESTS HOW PROCESSIVITY IS ACHIEVED


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.204 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of Escherichia coli exonuclease I suggests how processivity is achieved.

Breyer, W.A.Matthews, B.W.

(2000) Nat.Struct.Mol.Biol. 7: 1125-1128

  • DOI: 10.1038/81978

  • PubMed Abstract: 
  • Exonuclease I (ExoI) from Escherichia coli is a monomeric enzyme that processively degrades single stranded DNA in the 3' to 5' direction and has been implicated in DNA recombination and repair. Determination of the structure of ExoI to 2.4 A resolut ...

    Exonuclease I (ExoI) from Escherichia coli is a monomeric enzyme that processively degrades single stranded DNA in the 3' to 5' direction and has been implicated in DNA recombination and repair. Determination of the structure of ExoI to 2.4 A resolution using X-ray crystallography verifies the expected correspondence between a region of ExoI and the exonuclease (or proofreading) domains of the DNA polymerases. The overall fold of ExoI also includes two other regions, one of which extends the exonuclease domain and another that can be described as an elaborated SH3 domain. These three regions combine to form a molecule that is shaped like the letter C, although it also contains a segment that effectively converts the C into an O-like shape. The structure of ExoI thus provides additional support for the idea that DNA metabolizing enzymes achieve processivity by completely enclosing the DNA.


    Organizational Affiliation

    Institute of Molecular Biology, Howard Hughes Medical Institute, 1229 University of Oregon, Eugene, Oregon 97403-1229, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
EXONUCLEASE I
A
482Escherichia coli (strain K12)Gene Names: sbcB (cpeA, xonA)
EC: 3.1.11.1
Find proteins for P04995 (Escherichia coli (strain K12))
Go to UniProtKB:  P04995
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

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

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Download CCD File 
A
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
MG
Query on MG

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Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.204 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 84.410α = 90.00
b = 84.410β = 90.00
c = 298.650γ = 120.00
Software Package:
Software NamePurpose
SHARPphasing
SCALEPACKdata scaling
DENZOdata reduction
CNSrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-12-06
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance