1JN4

The Crystal Structure of Ribonuclease A in complex with 2'-deoxyuridine 3'-pyrophosphate (P'-5') adenosine


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.295 
  • R-Value Work: 0.225 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Cleavage of 3',5'-Pyrophosphate-Linked Dinucleotides by Ribonuclease A and Angiogenin

Jardine, A.M.Leonidas, D.D.Jenkins, J.L.Park, C.Raines, R.T.Acharya, K.R.Shapiro, R.

(2001) Biochemistry 40: 10262-10272


  • PubMed Abstract: 
  • Recently, 3',5'-pyrophosphate-linked 2'-deoxyribodinucleotides were shown to be >100-fold more effective inhibitors of RNase A superfamily enzymes than were the corresponding monophosphate-linked (i.e., standard) dinucleotides. Here, we have investig ...

    Recently, 3',5'-pyrophosphate-linked 2'-deoxyribodinucleotides were shown to be >100-fold more effective inhibitors of RNase A superfamily enzymes than were the corresponding monophosphate-linked (i.e., standard) dinucleotides. Here, we have investigated two ribo analogues of these compounds, cytidine 3'-pyrophosphate (P'-->5') adenosine (CppA) and uridine 3'-pyrophosphate (P'-->5') adenosine (UppA), as potential substrates for RNase A and angiogenin. CppA and UppA are cleaved efficiently by RNase A, yielding as products 5'-AMP and cytidine or uridine cyclic 2',3'-phosphate. The k(cat)/K(m) values are only 4-fold smaller than for the standard dinucleotides CpA and UpA, and the K(m) values (10-16 microM) are lower than those reported for any earlier small substrates (e.g., 500-700 microM for CpA and UpA). The k(cat)/K(m) value for CppA with angiogenin is also only severalfold smaller than for CpA, but the effect of lengthening the internucleotide linkage on K(m) is more modest. Ribonucleotide 3',5'-pyrophosphate linkages were proposed previously to exist in nature as chemically labile intermediates in the pathway for the generation of cyclic 2',3'-phosphate termini in various RNAs. We demonstrate that in fact they are relatively stable (t(1/2) > 15 days for uncatalyzed degradation of UppA at pH 6 and 25 degrees C) and that cleavage in vivo is most likely enzymatic. Replacements of the RNase A catalytic residues His12 and His119 by alanine reduce activity toward UppA by approximately 10(5)-and 10(3.3)-fold, respectively. Thus, both residues play important roles. His12 probably acts as a base catalyst in cleavage of UppA (as with RNA). However, the major function of His119 in RNA cleavage, protonation of the 5'-O leaving group, is not required for UppA cleavage because the pK(a) of the leaving group is much lower than that for RNA substrates. A crystal structure of the complex of RNase A with 2'-deoxyuridine 3'-pyrophosphate (P'-->5') adenosine (dUppA), determined at 1.7 A resolution, together with models of the UppA complex based on this structure suggest that His119 contributes to UppA cleavage through a hydrogen bond with a nonbridging oxygen atom in the pyrophosphate and through pi-pi stacking with the six-membered ring of adenine.


    Organizational Affiliation

    Center for Biochemical and Biophysical Sciences and Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Pancreatic Ribonuclease A
A, B
124Bos taurusGene Names: RNASE1 (RNS1)
EC: 3.1.27.5
Find proteins for P61823 (Bos taurus)
Go to Gene View: RNASE1
Go to UniProtKB:  P61823
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
139
Query on 139

Download SDF File 
Download CCD File 
A
ADENOSINE-5'-[TRIHYDROGEN DIPHOSPHATE] P'-3'-ESTER WITH 2'-DEOXYURIDINE
C19 H25 N7 O14 P2
NGHFJGUDQJTSRY-LNAOLWRRSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
139Ki: 11300 nM BINDINGMOAD
139Ki: 11300 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.295 
  • R-Value Work: 0.225 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 99.822α = 90.00
b = 32.291β = 90.04
c = 72.061γ = 90.00
Software Package:
Software NamePurpose
XDSdata scaling
AMoREphasing
X-PLORrefinement
XDSdata reduction
AUTOMARdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-06-03
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-04
    Type: Refinement description