Systematic Veterinary Virology

MORPHOLOGY

• Adenovirus particles are non-enveloped (hence not ether sensitive) and 60-90nm in diameter. The capsid has icosahedral sy mmetry. The capsid is composed of a single layer. The capsid comprises of 252 capsomers: 240 "hexons" + 12 "pentons" at vertices of icosahedron (2-3-5 symmetry).
• The surface projections are distinct, one or two filaments protruding from the 12 vertices. The pentons have a toxin-like activity (purified pentons cause c.p.e. in the absence of any other virus components (a unique property). A trimeric fibre protein extends from each of the 12 vectices (attached to the penton base proteins) and is responsible for recognition and binding to the cellular receptor.
• Adenoviruses have ten proteins. The genome is linear, non-segmented and d/s DNA . The complete genome is 35800-36200 nucleotides long.