1EOW

CRYSTAL STRUCTURE OF RIBONUCLEASE A COMPLEXED WITH URIDYLYL(2',5')GUANOSINE (NON-PRODUCTIVE BINDING)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.187 
  • R-Value Observed: 0.187 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Productive and nonproductive binding to ribonuclease A: X-ray structure of two complexes with uridylyl(2',5')guanosine.

Vitagliano, L.Merlino, A.Zagari, A.Mazzarella, L.

(2000) Protein Sci 9: 1217-1225

  • DOI: https://doi.org/10.1110/ps.9.6.1217
  • Primary Citation of Related Structures:  
    1EOS, 1EOW

  • PubMed Abstract: 

    Guanine-containing mono- and dinucleotides bind to the active site of ribonuclease A in a nonproductive mode (retro-binding) (Aguilar CF, Thomas PJ, Mills A, Moss DS, Palmer RA. 1992. J Mol Biol 224:265-267). Guanine binds to the highly specific pyrimidine site by forming hydrogen bonds with Thr45 and with the sulfate anion located in the P1 site. To investigate the influence of the anion present in the P1 site on retro-binding, we determined the structure of two new complexes of RNase A with uridylyl(2',5')guanosine obtained by soaking two different forms of pre-grown RNase A crystals. In one case, RNase A was crystallized without removing the sulfate anion strongly bound to the active site; in the other, the protein was first equilibrated with a basic solution to displace the anion from the P1 site. The X-ray structures of the complexes with and without sulfate in P1 were refined using diffraction data up to 1.8 A (R-factor 0.192) and 2.0 A (R-factor 0.178), respectively. The binding mode of the substrate analogue to the protein differs markedly in the two complexes. When the sulfate is located in P1, we observe retro-binding; whereas when the anion is removed from the active site, the uridine is productively bound at the B1 site. In the productive complex, the electron density is very well defined for the uridine moiety, whereas the downstream guanine is disordered. This finding indicates that the interactions of guanine in the B2 site are rather weak and that this site is essentially adenine preferring. In this crystal form, there are two molecules per asymmetric unit, and due to crystal packing, only the active site of one molecule is accessible to the ligand. Thus, in the same crystal we have a ligand-bound and a ligand-free RNase A molecule. The comparison of these two structures furnishes a detailed and reliable picture of the structural alterations induced by the binding of the substrate. These results provide structural information to support the hypotheses on the role of RNase A active site residues that have recently emerged from site-directed mutagenesis studies.


  • Organizational Affiliation

    Centro di Studio di Biocristallografia, CNR, Universita' degli Studi di Napoli Federico II, Italy.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
RIBONUCLEASE PANCREATIC124Bos taurusMutation(s): 0 
EC: 3.1.27.5
UniProt
Find proteins for P61823 (Bos taurus)
Explore P61823 
Go to UniProtKB:  P61823
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP61823
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
U2G
Query on U2G

Download Ideal Coordinates CCD File 
C [auth A]URIDYLYL-2'-5'-PHOSPHO-GUANOSINE
C19 H24 N7 O13 P
DFYLLEBFVZTKHD-VMIOUTBZSA-N
SO4
Query on SO4

Download Ideal Coordinates CCD File 
B [auth A]SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.187 
  • R-Value Observed: 0.187 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 30.34α = 90
b = 38.35β = 106.8
c = 53.85γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
X-PLORmodel building
X-PLORrefinement
X-PLORphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2000-11-17
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance