1P7M

SOLUTION STRUCTURE AND BASE PERTURBATION STUDIES REVEAL A NOVEL MODE OF ALKYLATED BASE RECOGNITION BY 3-METHYLADENINE DNA GLYCOSYLASE I


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 25 
  • Selection Criteria: structures with acceptable covalent geometry,structures with favorable non-bond energy,structures with the least restraint violations,structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Solution structure and base perturbation studies reveal a novel mode of alkylated base recognition by 3-methyladenine DNA glycosylase I

Cao, C.Kwon, K.Jiang, Y.L.Drohat, A.C.Stivers, J.T.

(2003) J.Biol.Chem. 278: 48012-48020

  • DOI: 10.1074/jbc.M307500200

  • PubMed Abstract: 
  • The specific recognition mechanisms of DNA repair glycosylases that remove cationic alkylpurine bases in DNA are not well understood partly due to the absence of structures of these enzymes with their cognate bases. Here we report the solution struct ...

    The specific recognition mechanisms of DNA repair glycosylases that remove cationic alkylpurine bases in DNA are not well understood partly due to the absence of structures of these enzymes with their cognate bases. Here we report the solution structure of 3-methyladenine DNA glycosylase I (TAG) in complex with its 3-methyladenine (3-MeA) cognate base, and we have used chemical perturbation of the base in combination with mutagenesis of the enzyme to evaluate the role of hydrogen bonding and pi-cation interactions in alkylated base recognition by this DNA repair enzyme. We find that TAG uses hydrogen bonding with heteroatoms on the base, van der Waals interactions with the 3-Me group, and conventional pi-pi stacking with a conserved Trp side chain to selectively bind neutral 3-MeA over the cationic form of the base. Discrimination against binding of the normal base adenine is derived from direct sensing of the 3-methyl group, leading to an induced-fit conformational change that engulfs the base in a box defined by five aromatic side chains. These findings indicate that base specific recognition by TAG does not involve strong pi-cation interactions, and suggest a novel mechanism for alkylated base recognition and removal.


    Organizational Affiliation

    Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2185, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
DNA-3-methyladenine glycosylase I
A
187Escherichia coli (strain K12)Gene Names: tag
EC: 3.2.2.20
Find proteins for P05100 (Escherichia coli (strain K12))
Go to UniProtKB:  P05100
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
ADK
Query on ADK

Download SDF File 
Download CCD File 
A
3-METHYL-3H-PURIN-6-YLAMINE
3-METHYLADENINE
C6 H7 N5
FSASIHFSFGAIJM-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
ADKKd: 42000 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 25 
  • Selection Criteria: structures with acceptable covalent geometry,structures with favorable non-bond energy,structures with the least restraint violations,structures with the lowest energy 
  • Olderado: 1P7M Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-11-25
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance