2QEF

X-ray structure of 7-deaza-dG and Z3dU modified duplex CGCGAATXCZCG


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.181 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

A bridging water anchors the tethered 5-(3-aminopropyl)-2'-deoxyuridine amine in the DNA major groove proximate to the N+2 C.G base pair: implications for formation of interstrand 5'-GNC-3' cross-links by nitrogen mustards.

Wang, F.Li, F.Ganguly, M.Marky, L.A.Gold, B.Egli, M.Stone, M.P.

(2008) Biochemistry 47: 7147-7157

  • DOI: https://doi.org/10.1021/bi800375m
  • Primary Citation of Related Structures:  
    2QEF, 2QEG

  • PubMed Abstract: 

    Site-specific insertion of 5-(3-aminopropyl)-2'-deoxyuridine (Z3dU) and 7-deaza-dG into the Dickerson-Drew dodecamers 5'-d(C (1)G (2)C (3)G (4)A (5)A (6)T (7)T (8)C (9) Z (10)C (11)G (12))-3'.5'-d(C (13)G (14)C (15)G (16)A (17)A (18)T (19)T (20)C (21) Z (22)C (23)G (24))-3' (named DDD (Z10)) and 5'-d(C (1)G (2)C (3)G (4)A (5)A (6)T (7) X (8)C (9) Z (10)C (11)G (12))-3'.5'-d(C (13)G (14)C (15)G (16)A (17)A (18)T (19) X (20)C (21) Z (22)C (23)G (24))-3' (named DDD (2+Z10)) (X = Z3dU; Z = 7-deaza-dG) suggests a mechanism underlying the formation of interstrand N+2 DNA cross-links by nitrogen mustards, e.g., melphalan and mechlorethamine. Analysis of the DDD (2+Z10) duplex reveals that the tethered cations at base pairs A (5).X (20) and X (8).A (17) extend within the major groove in the 3'-direction, toward conserved Mg (2+) binding sites located adjacent to N+2 base pairs C (3).Z (22) and Z (10).C (15). Bridging waters located between the tethered amines and either Z (10) or Z (22) O (6) stabilize the tethered cations and allow interactions with the N + 2 base pairs without DNA bending. Incorporation of 7-deaza-dG into the DDD (2+Z10) duplex weakens but does not eliminate electrostatic interactions between tethered amines and Z (10) O (6) and Z (22) O (6). The results suggest a mechanism by which tethered N7-dG aziridinium ions, the active species involved in formation of interstrand 5'-GNC-3' cross-links by nitrogen mustards, modify the electrostatics of the major groove and position the aziridinium ions proximate to the major groove edge of the N+2 C.G base pair, facilitating interstrand cross-linking.


  • Organizational Affiliation

    Department of Chemistry, Center in Molecular Toxicology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235, USA.


Macromolecules

Find similar nucleic acids by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains LengthOrganismImage
DNA (5'-D(*DCP*DGP*DCP*DGP*DAP*DAP*DTP*(ZDU)P*DCP*(7GU)P*DCP*DG)-3')
A, B
12N/A
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.181 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 24.858α = 90
b = 41.057β = 90
c = 66.615γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data collection
HKL-2000data reduction
HKL-2000data scaling
EPMRphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-05-06
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2023-08-30
    Changes: Data collection, Database references, Derived calculations, Refinement description