Purification of virus suspensions

Abstract

For studies upon the nature and properties of plant viruses it is necessary to free the latter from as much as possible of the proteins and other extraneous plant materials in the virus sap. Because of this a great deal of work from the purely chemical point of view has been carried out on virus suspensions and many different methods of purification have been evolved which are not, however, applicable to all plant viruses. One of the earliest methods of purification was that used by Vinson and Petre (139) for Nicotiana Virus I (tobacco mosaic virus). They found that an aqueous solution of safranin precipitates the virus from the sap of diseased tobacco plants, the precipitate containing nearly all the virus. The latter is apparently held in an inactive condition in the precipitate but is released when the safranin is removed by means of amyl alcohol.