What is a virus? The case of tobacco mosaic disease

The role played by studies of tobacco mosaic virus (TMV) in the development of virology is summarized. TMV was the first virus shown to be able to pass through a bacteria-retaining filter; it was also the first virus to be crystallized, to have its morphology and structure elucidated and its coat protein sequenced. Experiments done with TMV RNA in the 1950s established that viral nucleic acid is the carrier of viral infectivity. The mechanism of...