1D60

THE STRUCTURE OF THE B-DNA DECAMER C-C-A-A-C-I-T-T-G-G: TRIGONAL FORM


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.20 Å
  • R-Value Observed: 0.162 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structure of the B-DNA decamer C-C-A-A-C-I-T-T-G-G in two different space groups: conformational flexibility of B-DNA.

Lipanov, A.Kopka, M.L.Kaczor-Grzeskowiak, M.Quintana, J.Dickerson, R.E.

(1993) Biochemistry 32: 1373-1389

  • DOI: 10.1021/bi00056a024
  • Primary Citation of Related Structures:  
    1D60, 1D61, 1D62

  • PubMed Abstract: 
  • For the first time, the same B-DNA oligomer has been crystallized and its structure solved in two different space groups. Crystallization of C-C-A-A-C-I-T-T-G-G with Ca2+ yields monoclinic space group C2 with a = 31.87 A, b = 25.69 A, c = 34.21 A, beta = 114 ...

    For the first time, the same B-DNA oligomer has been crystallized and its structure solved in two different space groups. Crystallization of C-C-A-A-C-I-T-T-G-G with Ca2+ yields monoclinic space group C2 with a = 31.87 A, b = 25.69 A, c = 34.21 A, beta = 114.1 degrees, and five base pairs per asymmetric unit. The 5026 2 sigma data to 1.3 A refine to R = 0.152 with 72 waters, one heptavalent hydrated calcium complex, and one cacodylate ion per asymmetric unit. In contrast, crystallization with Mg2+ yields trigonal space group P3(2)21 with a = b = 33.23 A, c = 94.77 A, gamma = 120 degrees, and 10 base pairs per asymmetric unit. The 1725 2 sigma data to 2.2 A refine to R = 0.164 with 36 water molecules and one octahedral magnesium complex per asymmetric unit. The monoclinic form is virtually isostructural with previously solved monoclinic decamers, including twist angles of ca. 50 degrees at C-A and T-G steps. In contrast, the trigonal structure has quite different local helix parameters, with twist angles of ca. 36 degrees at the corresponding steps. These local parameter differences can only be attributed to crystal packing, suggesting that certain sequences of B-DNA are more flexible and influenced by their surroundings than had previously been thought. Such deformability may be important for interaction of B-DNA with control proteins, where both static structure and dynamic deformability comprise components of the recognition process. The crossing of two helices at an angle of 120 degrees in the trigonal cell is a model for an antiparallel, uncrossed Holliday junction, as has been noted earlier by Timsit and Moras [Timsit, Y., & Moras, D. (1991) J. Mol. Biol. 221, 919-940] from a rhombohedral DNA dodecamer structure analysis.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, University of California, Los Angeles 90024.



Macromolecules

Find similar nucleic acids by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChainsLengthOrganismImage
DNA (5'-D(*CP*CP*AP*AP*CP*IP*TP*TP*GP*G)-3')A, B10N/A
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download Ideal Coordinates CCD File 
C [auth B]MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.20 Å
  • R-Value Observed: 0.162 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 33.23α = 90
b = 33.23β = 90
c = 94.77γ = 120
Software Package:
Software NamePurpose
NUCLSQrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1993-04-15
    Type: Initial release
  • Version 1.1: 2008-05-22
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance