Action of High Pressures on Plant Viruses

Abstract

Two of us (J. Basset and M. Macheboeuf) with the help of several coworkers 1 have submitted different biological samples to the action of an apparatus devised several years ago by Basset 2 which realizes enormous pressures (beyond 20,000 atmospheres). Non-sporulated bacteria were killed after 45 minutes of exposure to a pressure around 5,000 atmospheres, while sporulated bacteria resist as high pressures as 20,000 atmospheres. Certain viruses and bacteriophages, on the contrary, are inactivated at pressures around 3,000-4,000 atmospheres, while some enzymes are inactivated at about 13,000 atmospheres and toxins at 17,000-19,000 atmospheres. Thus, if toxins behave much like enzymes, bacteriophages behave more like viruses. Globulins are denatured around 8,000 atmospheres while albumins usually resist much higher pressures.

On the other hand, two of us (Gratia and Manil) 3 studying the antigenic properties of plant viruses have found that there exist a few which are not only neutralized by the action of corresponding anti-serums but are also heavily and specifically flocculated, while most of them are neutralized without exhibiting any precipitation. In the first group are the common mosaic of tobacco and the X virus of potato, while in the second are the virus of tobacco necrosis and Y virus of potato.