Biophysical Studies of the Virus System of Vesicular Stomatitis

Abstract

SUMMARY: Biophysical studies of the virus system of vesicular stomatitis passaged in eggs showed that the major part of the infectivity was associated with a component of sedimentation coefficient 625S. A component of sedimentation coefficient 330 S was observed also, and is probably a non-infective product of the disintegration of the 625S component. These components contribute about 35% of the total complement-fixing activity of the virus system. All infective materials were handled in subdued light (Skinner & Bradish, 1954). Electron micrographs of concentrates of the infective fraction revealed rods, of length 175 mμ. and diameter 69 mμ., and almost spherical granules of diameter 65 mμ. These particles are identified with the 625S and 330S sedimentation components. The remaining 65% of the total complement-fixing activity was associated with two discrete components of sedimentation coefficients about 20S and 6S. The first of these components may contribute up to 0·1% of the total infectivity of the virus system. The structure of the virus system is discussed in relation to the data obtained.