2PYS

Crystal Structure of a Five Site Mutated Cyanovirin-N with a Mannose Dimer Bound at 1.8 A Resolution


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.215 
  • R-Value Work: 0.169 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

A Monovalent Mutant of Cyanovirin-N Provides Insight into the Role of Multiple Interactions with gp120 for Antiviral Activity.

Fromme, R.Katiliene, Z.Giomarelli, B.Bogani, F.Mahon, J.M.Mori, T.Fromme, P.Ghirlanda, G.

(2007) Biochemistry 46: 9199-9207

  • DOI: 10.1021/bi700666m
  • Primary Citation of Related Structures:  
  • Also Cited By: 2RDK

  • PubMed Abstract: 
  • Cyanovirin-N (CV-N) is a 101 amino acid cyanobacterial lectin with potent antiviral activity against HIV, mediated by high-affinity binding to branched N-linked oligomannosides on the viral surface envelope protein gp120. The protein contains two car ...

    Cyanovirin-N (CV-N) is a 101 amino acid cyanobacterial lectin with potent antiviral activity against HIV, mediated by high-affinity binding to branched N-linked oligomannosides on the viral surface envelope protein gp120. The protein contains two carbohydrate-binding domains, A and B, each of which binds short oligomannosides independently in vitro. The interaction to gp120 could involve either a single domain or both domains simultaneously; it is not clear which mode would elicit the antiviral activity. The model is complicated by the formation of a domain-swapped dimer form, in which part of each domain is exchanged between two monomers, which contains four functional carbohydrate-binding domains. To clarify whether multivalent interactions with gp120 are necessary for the antiviral activity, we engineered a novel mutant, P51G-m4-CVN, in which the binding site on domain A has been knocked out; in addition, a [P51G] mutation prevents the formation of domain-swapped dimers under physiological conditions. Here, we present the crystal structures at 1.8 A of the free and of the dimannose-bound forms of P51G-m4-CVN, revealing a monomeric structure in which only domain B is bound to dimannose. P51G-m4-CVN binds gp120 with an affinity almost 2 orders of magnitude lower than wt CV-N and is completely inactive against HIV. The tight binding to gp120 is recovered in the domain-swapped version of P51G-m4-CVN, prepared under extreme conditions. Our findings show that the presence of at least two oligomannoside-binding sites, either by the presence of intact domains A and B or by formation of domain-swapped dimers, is essential for activity.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Cyanovirin-N
A, B
109Nostoc ellipsosporumMutation(s): 5 
Find proteins for P81180 (Nostoc ellipsosporum)
Go to UniProtKB:  P81180
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MAN
Query on MAN

Download SDF File 
Download CCD File 
C, D
ALPHA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-PQMKYFCFSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.215 
  • R-Value Work: 0.169 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 49.226α = 90.00
b = 38.281β = 99.69
c = 55.794γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
PHASERphasing
CrystalCleardata collection
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-07-31
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance