Isolation of a crystalline protein possessing the properties of tobacco-mosaic virus.

Stanley first crystallized a virus— tobacco mosaic virus. The following year Bawden, Pirie, Bernal and Fankuchen (No. 12005) showed that tobacco mosaic virus molecules are asnisometric and consist of ribonucleoprotein.

In 1946 Stanley and John Howard Northrop received half of the Nobel Prize in Chemistry "for their preparation of enzymes and virus proteins in a pure form." The other half was  awarded to James Batcheller Sumner "for his discovery that enzymes can be crystallized."