How was Wendell Meredith Stanley awarded the Noble Prize?

Name: Wendell Meredith Stanley
Country: Indiana U.S.
Date of Bitrh: August 16, 1904
Date of Death: June 15, 1971 (Salamanca Spain)
Subject of Study: Tobacco mosaic virus and virus
Noble Prize Year: Nobel Prize for Chemistry in 1946 for his work in the purification and crystallization of viruses, thus demonstrating their molecular structure.
About: Wendell Meredith Stanley obtained his doctorate from the University of Illinois in 1929. He worked from 1932 to 1948 at the Rockefeller Institute for Medical Research (Rockefeller University) facilities in Princeton, N.J. In 1935, Stanley crystallised the tobacco mosaic virus (TMV, the causative agent of a plant disease) and showed that it is a rod-shaped aggregate of protein and nucleic acid molecules. His work enabled other scientists, utilising methods of X-ray diffraction, to ascertain unambiguously the precise molecular structures and the modes of propagation of several viruses.
While a professor of biochemistry and director of the laboratory for virus research at the University of California, Berkeley (1948–71), Stanley studied influenza viruses, for which he developed a preventive vaccine.