1RXA

CRYSTAL STRUCTURE OF R(CCCCGGGG) IN TWO DISTINCT LATTICES

• PDB DOI: https://doi.org/10.2210/pdb1RXA/pdb
• NAKB: 1RXA

• Classification: RNA
• Mutation(s): No 


• Deposited: 1995-05-05 Released: 1996-10-20 
• Deposition Author(s): Portmann, S., Usman, N., Egli, M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Work: 0.250 
• R-Value Observed: 0.250 

Literature

The crystal structure of r(CCCCGGGG) in two distinct lattices.

Portmann, S., Usman, N., Egli, M.

(1995) Biochemistry 34: 7569-7575

• PubMed: 7779802 
• DOI: https://doi.org/10.1021/bi00023a002
• Primary Citation of Related Structures:  
  1RXA, 1RXB


• PubMed Abstract: 
  

  The structure of the RNA octamer r(C4G4) has been determined in two different crystal forms. The conformations of the RNA duplex in the rhombohedral and hexagonal lattices display only minimal deviations, demonstrating that the RNA double helix is considerably less deformable than the DNA double helix. For the first time the crystal structures of an A-RNA and an A-DNA with identical sequence can now be compared. The large number of ordered water molecules observed in the minor groove of the RNA duplex suggests that an important contribution to its higher rigidity derives from the improved hydration due to the presence of the 2'-hydroxyl groups. Our finding that the conformation of the RNA double helix is virtually unaffected by different crystal packing modes provides evidence that proteins may not alter the conformation of RNA stem regions in a significant way.

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Organizational Affiliation: 

Organic Chemistry Laboratory, ETH Swiss Federal Institute of Technology, Zürich.

Biological Assembly 1  

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 2.56 kDa 
• Atom Count: 169 
• Modelled Residue Count: 8 
• Deposited Residue Count: 8 
• Unique nucleic acid chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Length	Organism	Image
RNA (5'-R(*CP*CP*CP*CP*GP*GP*GP*G)-3')	A	8	N/A

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Work: 0.250 
• R-Value Observed: 0.250 
• Space Group: P 6₁ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 39.734	α = 90
b = 39.734	β = 90
c = 58.545	γ = 120

Software Package:

Software Name	Purpose
X-PLOR	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 1996-10-20 
Deposition Author(s): Portmann, S., Usman, N., Egli, M.

Revision History  

• Version 1.0: 1996-10-20
  Type: Initial release
  
• Version 1.1: 2008-05-22
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-14
  Changes: Data collection, Database references