Virion Structure of a Poxvirus

The virions of poxviruses consist of
· a surface membrane
· a core
· Lateral bodies.
· They may or may not have an envelope.

They produce extracellular and intracellular particles during their life cycle and can occur in two phenotypes. They may be enveloped during their extracellular phase. Extracellular virions initiate the infection. The virus may be sequestered within inclusion bodies that are not occluded and typically contain one nucleocapsid. The virion capsid is enveloped.

Virions are generally ovoid and brick-shaped. They are composed of an external coat containing lipid and tubular or globular protein structures, enclosing one or two lateral bodies and a core. The core can be unilaterally concave, biconcave, or cylindrical with one or two lateral bodies. Lateral bodies are usually lens-shaped and nested between the core membranes, or between the surface membranes.


Thin section of cowpox.














lb - lateral bodies, c - core The bar represents 100 nm.


Thin section of infected chick embryo cell

















pictures extracted: http://www.ncbi.nlm.nih.gov/ICTVdb/WIntkey/Images/em_poxvi.htm