1ZA7

The crystal structure of salt stable cowpea cholorotic mottle virus at 2.7 angstroms resolution.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Work: 0.245 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Enhanced local symmetry interactions globally stabilize a mutant virus capsid that maintains infectivity and capsid dynamics.

Speir, J.A.Bothner, B.Qu, C.Willits, D.A.Young, M.J.Johnson, J.E.

(2006) J.Virol. 80: 3582-3591

  • DOI: 10.1128/JVI.80.7.3582-3591.2006

  • PubMed Abstract: 
  • Structural transitions in viral capsids play a critical role in the virus life cycle, including assembly, disassembly, and release of the packaged nucleic acid. Cowpea chlorotic mottle virus (CCMV) undergoes a well-studied reversible structural expan ...

    Structural transitions in viral capsids play a critical role in the virus life cycle, including assembly, disassembly, and release of the packaged nucleic acid. Cowpea chlorotic mottle virus (CCMV) undergoes a well-studied reversible structural expansion in vitro in which the capsid expands by 10%. The swollen form of the particle can be completely disassembled by increasing the salt concentration to 1 M. Remarkably, a single-residue mutant of the CCMV N-terminal arm, K42R, is not susceptible to dissociation in high salt (salt-stable CCMV [SS-CCMV]) and retains 70% of wild-type infectivity. We present the combined structural and biophysical basis for the chemical stability and viability of the SS-CCMV particles. A 2.7-A resolution crystal structure of the SS-CCMV capsid shows an addition of 660 new intersubunit interactions per particle at the center of the 20 hexameric capsomeres, which are a direct result of the K42R mutation. Protease-based mapping experiments of intact particles demonstrate that both the swollen and closed forms of the wild-type and SS-CCMV particles have highly dynamic N-terminal regions, yet the SS-CCMV particles are more resistant to degradation. Thus, the increase in SS-CCMV particle stability is a result of concentrated tethering of subunits at a local symmetry interface (i.e., quasi-sixfold axes) that does not interfere with the function of other key symmetry interfaces (i.e., fivefold, twofold, quasi-threefold axes). The result is a particle that is still dynamic but insensitive to high salt due to a new series of bonds that are resistant to high ionic strength and preserve the overall particle structure.


    Related Citations: 
    • A salt stable mutant of cowpea chlorotic mottle virus.
      Bancroft, J.B.,Rees, M.W.,Johnson, M.W.,Dawson, J.R.O.
      (1973) J.Gen.Virol. 21: 507
    • Analysis of a salt stable mutant of cowpea chlorotic mottle virus.
      Fox, J.M.,Zhao, X.,Speir, J.A.,Young, M.J.
      (1996) Virology 222: 115
    • Structures of the native and swollen forms of cowpea chlorotic mottle virus determined by x-ray crystallography and cryo-electron microscopy.
      Speir, J.A.,Munshi, S.,Wang, G.,Baker, T.S.,Johnson, J.E.
      (1995) Structure 3: 63


    Organizational Affiliation

    Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Rd., La Jolla, CA 92037, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Coat protein
A, B, C
165Cowpea chlorotic mottle virusMutation(s): 1 
Find proteins for P03601 (Cowpea chlorotic mottle virus)
Go to UniProtKB:  P03601
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Work: 0.245 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 365.480α = 90.00
b = 374.860β = 90.00
c = 402.490γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
GLRFphasing
SCALEPACKdata scaling
PDB_EXTRACTdata extraction
RAVEphasing
DENZOdata reduction
CCP4phasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-03-21
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-11
    Type: Refinement description