4EMR

Crystal Structure determination of type1 ribosome inactivating protein complexed with 7-methylguanosine-triphosphate at 1.75A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.205 
  • R-Value Observed: 0.208 

wwPDB Validation   3D Report Full Report


This is version 2.0 of the entry. See complete history


Literature

First structural evidence of sequestration of mRNA cap structures by type 1 ribosome inactivating protein from Momordica balsamina.

Kushwaha, G.S.Yamini, S.Kumar, M.Sinha, M.Kaur, P.Sharma, S.Singh, T.P.

(2013) Proteins 81: 896-905

  • DOI: 10.1002/prot.24248
  • Primary Citation of Related Structures:  
    4I47, 4EMR, 4EMF

  • PubMed Abstract: 
  • This is the first structural evidence of recognition of mRNA cap structures by a ribosome inactivating protein. It is well known that a unique cap structure is formed at the 5' end of mRNA for carrying out various processes including mRNA maturation, translation initiation, and RNA turnover ...

    This is the first structural evidence of recognition of mRNA cap structures by a ribosome inactivating protein. It is well known that a unique cap structure is formed at the 5' end of mRNA for carrying out various processes including mRNA maturation, translation initiation, and RNA turnover. The binding studies and crystal structure determinations of type 1 ribosome inactivating protein (RIP-1) from Momordica balsamina (MbRIP-1) were carried out with mRNA cap structures including (i) N7-methyl guanine (m7G), (ii) N7-methyl guanosine diphosphate (m7GDP), and (iii) N7-methyl guanosine triphosphate (m7GTP). These compounds showed affinities to MbRIP-1 at nanomolar concentrations. The structure determinations of the complexes of MbRIP-1 with m7G, m7GDP, and m7GTP at 2.65, 1.77, and 1.75 Å resolutions revealed that all the three compounds bound to MbRIP-1 in the substrate binding site at the positions which are slightly shifted towards Glu85 as compared to those of rRNA substrates. In this position, Glu85 forms several hydrogen bonds with guanine moiety while N-7 methyl group forms van der Waals contacts. However, the guanine rings are poorly stacked in these complexes. Thus, the mode of binding by MbRIP-1 to mRNA cap structures is different which results in the inhibition of depurination. Since some viruses are known to exploit the capping property of the host, this action of MbRIP-1 may have implications for the antiviral activity of this protein in vivo. The understanding of the mode of binding of MbRIP-1 to cap structures may also assist in the design of anti-viral agents.


    Organizational Affiliation

    Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
rRNA N-glycosidase A246Momordica balsaminaMutation(s): 0 
Gene Names: RIP
EC: 3.2.2.22
Find proteins for D9J2T9 (Momordica balsamina)
Explore D9J2T9 
Go to UniProtKB:  D9J2T9
Protein Feature View
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  • Reference Sequence
Oligosaccharides

Help

Entity ID: 2
MoleculeChainsChain Length2D Diagram Glycosylation3D Interactions
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose
B
2 N-Glycosylation Oligosaccharides Interaction
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MGP
Query on MGP

Download Ideal Coordinates CCD File 
A
7-METHYL-GUANOSINE-5'-TRIPHOSPHATE
C11 H19 N5 O14 P3
DKVRNHPCAOHRSI-KQYNXXCUSA-O
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
MGPKd :  32.099998474121094   nM  PDBBind
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.205 
  • R-Value Observed: 0.208 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 130.065α = 90
b = 130.065β = 90
c = 40.277γ = 120
Software Package:
Software NamePurpose
HKL-2000data collection
AMoREphasing
REFMACrefinement
HKL-2000data reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2012-05-02
    Type: Initial release
  • Version 1.1: 2013-05-15
    Changes: Database references
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Structure summary