Adenovirus
Recombinant adenovirus as seen with transmission electron microscope following negative stain.
Engineered adenovirus is frequently used as vectors for the delivery of special genes into target cells.
This micrograph shows a group of adenovirus with characteristic icosahedra conformation. Doughnut-shaped hexon units are visible in most
of the virion particles. Peudo-color added Photoshop CS4.