Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 19.77 kDa 
• Atom Count: 1402 
• Residue Count: 180 
• Unique protein chains: 1

1SFE

ADA O6-METHYLGUANINE-DNA METHYLTRANSFERASE FROM ESCHERICHIA COLI

• DOI: 10.2210/pdb1SFE/pdb

• Classification: DNA BINDING PROTEIN
• Organism(s): Escherichia coli B
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1996-06-21 Released: 1996-12-23 
• Deposition Author(s): Moore, M.H., Gulbis, J.M., Dodson, E.J., Demple, B., Moody, P.C.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Work: 0.219 

Literature

Crystal structure of a suicidal DNA repair protein: the Ada O6-methylguanine-DNA methyltransferase from E. coli.

Moore, M.H., Gulbis, J.M., Dodson, E.J., Demple, B., Moody, P.C.

(1994) EMBO J 13: 1495-1501

• PubMed: 8156986 
• Primary Citation of Related Structures:  
  1SFE


• PubMed Abstract: 
  

The mutagenic and carcinogenic effects of simple alkylating agents are mainly due to methylation at the O6 position of guanine in DNA. O6-methylguanine directs the incorporation of either thymine or cytosine without blocking DNA replication, resulting in GC to AT transition mutations. In prokaryotic and eukaryotic cells antimutagenic repair is effected by direct reversal of this DNA damage. A suicidal methyltransferase repair protein removes the methyl group from DNA to one of its own cysteine residues. The resulting self-methylation of the active site cysteine renders the protein inactive. Here we report the X-ray structure of the 19 kDa C-terminal domain of the Escherichia coli ada gene product, the prototype of these suicidal methyltransferases. In the crystal structure the active site cysteine is buried. We propose a model for the significant conformational change that the protein must undergo in order to bind DNA and effect methyl transfer.

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Related Citations: 

• Crystal Structure of E.Coli O6-Methylguanine-DNA Methyltransferase
  Moody, P.C.E., Moore, M.H.
  (1995) Novel Approaches In Anticancer Drug Design : Molecular Modelling--new Treatment Strategies (in: Contrib Oncol , V 49) --: 16

• Crystallization of O6-Methylguanine-DNA Methyltransferase from Escherichia Coli
  Moody, P.C., Demple, B.
  (1988) J Mol Biol 200: 751

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Organizational Affiliation: 

Department of Chemistry, University of York, UK.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ADA O6-METHYLGUANINE-DNA METHYLTRANSFERASE	A	180	Escherichia coli B	Mutation(s): 0  Gene Names: ADAC EC: 2.1.1.63 (PDB Primary Data), 2.1.1 (UniProt)
Find proteins for P06134 (Escherichia coli (strain K12)) Explore P06134  Go to UniProtKB:  P06134

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Work: 0.219 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 46.2	α = 90
b = 45.95	β = 114.06
c = 46.4	γ = 90

Software Package:

Software Name	Purpose
PROLSQ	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1996-06-21 
• Released Date: 1996-12-23 
Deposition Author(s): Moore, M.H., Gulbis, J.M., Dodson, E.J., Demple, B., Moody, P.C.E.

Revision History 

• Version 1.0: 1996-12-23
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Source and taxonomy, Version format compliance