Journal of Biological Physics

, Volume 38, Issue 4, pp 657–671 | Cite as

How simple can a model of an empty viral capsid be? Charge distributions in viral capsids

  • Anže Lošdorfer BožičEmail author
  • Antonio Šiber
  • Rudolf Podgornik
Original Paper


We investigate and quantify salient features of the charge distributions on viral capsids. Our analysis combines the experimentally determined capsid geometry with simple models for ionization of amino acids, thus yielding a detailed description of spatial distribution for positive and negative charges across the capsid wall. The obtained data is processed in order to extract the mean radii of distributions, surface charge densities, as well as dipole moment densities. The results are evaluated and examined in light of previously proposed models of capsid charge distributions, which are shown to have to some extent limited value when applied to real viruses.


Capsid Virus Electrostatics Geometry Icosahedron Dipole moment 



One of us (A.L.B.) thanks A. Ljubetič for introducing him to the Tcl scripting language in VMD.

A.L.B. acknowledges support from the Slovene Agency for Research and Development under a young researcher grant. A.Š. acknowledges support from the Ministry of Science, Education, and Sports of the Republic of Croatia (Grant No. 035-0352828-2837). R.P. acknowledges support from the Slovene Agency for Research and Development through research program P1-0055 and research project J1-4297.


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Anže Lošdorfer Božič
    • 1
    Email author
  • Antonio Šiber
    • 2
  • Rudolf Podgornik
    • 1
    • 3
  1. 1.Department of Theoretical PhysicsJožef Stefan InstituteLjubljanaSlovenia
  2. 2.Institute of PhysicsZagrebCroatia
  3. 3.Department of Physics, Faculty of Mathematics and PhysicsLjubljanaSlovenia

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