1C0C

BOVINE PANCREATIC RIBONUCLEASE A DESICCATED FOR 4.0 DAYS

• PDB DOI: https://doi.org/10.2210/pdb1C0C/pdb

• Classification: HYDROLASE
• Organism(s): Bos taurus
• Mutation(s): No 


• Deposited: 1999-07-15 Released: 1999-10-14 
• Deposition Author(s): Bell, J.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.268 
• R-Value Work: 0.185 
• R-Value Observed: 0.190 

Literature

X-ray crystal structures of a severely desiccated protein

Bell, J.A.

(1999) Protein Sci 8: 2033-2040

• PubMed: 10548049 
• DOI: https://doi.org/10.1110/ps.8.10.2033
• Primary Citation of Related Structures:  
  1C0B, 1C0C


• PubMed Abstract: 
  

  Unlike most protein crystals, form IX of bovine pancreatic ribonuclease A diffracts well when severely dehydrated. Crystal structures have been solved after 2.5 and 4 days of desiccation with CaSO4, at 1.9 and 2.0 A resolution, respectively. The two desiccated structures are very similar. An RMS displacement of 1.6 A is observed for main-chain atoms in each structure when compared to the hydrated crystal structure with some large rearrangements observed in loop regions. The structural changes are the result of intermolecular contacts formed by strong electrostatic interactions in the absence of a high dielectric medium. The electron density is very diffuse for some surface loops, consistent with a very disordered structure. This disorder is related to the conformational changes. These results help explain conformational changes during the lyophilization of protein and the associated phenomena of denaturation and molecular memory.

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Organizational Affiliation: 

Division of Molecular Medicine, Wadsworth Center, New York State Department of Health, Albany 12201-0509, USA. [e-mail]

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 14.35 kDa 
• Atom Count: 973 
• Modelled Residue Count: 124 
• Deposited Residue Count: 128 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
RIBONUCLEASE A	A	128	Bos taurus	Mutation(s): 0  EC: 3.1.27.5 (PDB Primary Data), 4.6.1.18 (UniProt)
UniProt
Find proteins for P61823 (Bos taurus) Explore P61823  Go to UniProtKB:  P61823

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	B [auth A], C [auth A], D [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.268 
• R-Value Work: 0.185 
• R-Value Observed: 0.190 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 35.7	α = 90
b = 39.7	β = 90
c = 50.8	γ = 90

Software Package:

Software Name	Purpose
bioteX	data collection
bioteX	data reduction
MERLOT	phasing
TNT	refinement
bioteX	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 1999-10-14 
Deposition Author(s): Bell, J.A.

Revision History  

• Version 1.0: 1999-10-14
  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: 2017-10-04
  Changes: Refinement description
• Version 1.4: 2024-10-30
  Changes: Data collection, Database references, Derived calculations, Structure summary