1FQ2

CRYSTAL STRUCTURE ANALYSIS OF THE POTASSIUM FORM OF B-DNA DODECAMER CGCGAATTCGCG

• PDB DOI: https://doi.org/10.2210/pdb1FQ2/pdb
• NAKB: 1FQ2

• Classification: DNA
• Mutation(s): No 


• Deposited: 2000-09-01 Released: 2000-11-27 
• Deposition Author(s): Williams, L.D., Sines, C.C., McFail-Isom, L., Howerton, S.B., VanDerveer, D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.215 
• R-Value Observed: 0.141 

Literature

Cations Mediate B-DNA Conformational Heterogeneity

Sines, C.C., McFail-Isom, L., Howerton, S.B., VanDerveer, D., Williams, L.D.

(2000) J Am Chem Soc 122: 11048-11056

• DOI: https://doi.org/10.1021/ja002244p

Biological Assembly 1  

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 7.55 kDa 
• Atom Count: 681 
• Modelled Residue Count: 24 
• Deposited Residue Count: 24 
• Unique nucleic acid chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Length	Organism	Image
DNA (5'-D(*CP*GP*CP*GP*AP*AP*TP*TP*CP*GP*CP*G)-3')	A, B	12	N/A

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SPM	D [auth B]	SPERMINE C10 H26 N4 PFNFFQXMRSDOHW-UHFFFAOYSA-N
MG	C [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.215 
• R-Value Observed: 0.141 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 25.588	α = 90
b = 40.818	β = 90
c = 66.673	γ = 90

Software Package:

Software Name	Purpose
SHELXS	phasing
SHELXL-97	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-11-27 
Deposition Author(s): Williams, L.D., Sines, C.C., McFail-Isom, L., Howerton, S.B., VanDerveer, D.

Revision History  

• Version 1.0: 2000-11-27
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-07
  Changes: Data collection, Database references, Derived calculations