What virus structure did Rosalind Franklin investigate later in her career?

Rosalind Franklin investigated the structure of tobacco mosaic virus, commonly abbreviated TMV, later in her career. After leaving King’s College London, she joined Birkbeck College and used X-ray crystallography to study viruses under John Desmond Bernal.

TMV was an especially important subject because it is a relatively simple rod-shaped virus containing RNA surrounded by a protein coat. Franklin’s research helped establish that the coat proteins were arranged in a helical pattern and that the viral particle was hollow rather than solid. She also supported the conclusion that TMV contains single-stranded RNA.

Franklin published major work on TMV beginning in 1955 and collaborated with Aaron Klug and her student Donald Caspar Holmes. She began constructing a large model of the virus for the 1958 Brussels World’s Fair, but died just before the exhibition opened. Klug continued the research and later received the 1982 Nobel Prize in Chemistry for work on biological macromolecular structures.