CENTRIFUGATION STUDIES ON PNEUMONIA VIRUS OF MICE (PVM) : THE RELATIVE SIZES OF FREE AND COMBINED VIRUS.

A technique has been devised for obtaining free or uncombined pneumonia virus of mice (PVM). Free PVM, liberated from infected mouse lungs by means of this technique, is infectious and causes hemagglutination directly. The results of quantitative studies carried out in the high speed angle centrifuge indicate that the free virus is relatively small, with dimensions of the order of 40 millimicrons.

MOLECULAR ASSOCIATION OF HEMOCYANIN PRODUCED BY X-RAYS AS OBSERVED IN THE ULTRACENTRIFUGE.

1. When normal, monodisperse hemocyanin (60.5S) from Limulus Rolyphemus was irradiated in neutral buffer with x-rays, several new, more rapidly sedimenting ultracentrifugal components (86S, 107S, 122S) were produced, with a corresponding loss in the amount of the unaffected protein.