The first virus ever to be discovered: tobacco mosaic virus (TMV), a positive-sense single stranded RNA virus that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes characteristic mosaic-like mottling and discoloration on the leaves. TMV virion has a rod-like appearance, ~300 nm in length and ~18 nm in diameter. The capsid is made from 2130 molecules of coat protein and one molecule of genomic single stranded RNA, 6400 bases long.
1. Sachse, C. et al. High-resolution electron microscopy of helical specimens: a fresh look at tobacco mosaic virus. Journal of molecular biology 371, 812-835, doi:10.1016/j.jmb.2007.05.088 (2007).