Effect of alcohol on the so-called bacteriophage of d'Herelle.

Abstract

D'Herelle 1 has reported that by precipitating a culture of anti-dysentery bacteriophage with nine volumes of 96 per cent alcohol, decanting the supernatant fluid after 48 hours and re-dissolving the precipitate in saline, he obtained a substance slightly lytic for dysentery bacilli (titer 5 cc.). This lytic action, however, was not transmissible in series. D'Herelle concluded that the alcohol, while destroying the living ultra-microbe (bacteriophage), had precipitated its endo-enzyme.

Hauduroy, 2 repeating these experiments, obtained similar results by precipitating sterile bouillon with alcohol. He decided that the apparent lytic action of the precipitate obtained by d'Herelle was due to a bacteriostatic effect of the alcohol adsorbed by this precipitate. Arnold 3 was not able to obtain any active substance by precipitation with alcohol. More recently, Appelmans 4 failed to destroy completely the lytic activity of bacteriophage by exposure of bacteriophage to 50 per cent alcohol, but he does not state whether the activity of the precipitates was transmissible in series.

In the course of some experiments in which we had occasion to precipitate filtrates of so-called “bacteriophage” with alcohol, it was observed that in some instances the re-dissolved alcoholic precipitates manifested appreciable lytic action. Considering the divergent results reported by the previously mentioned observers and in view of the interest that the effect of alcohol on the activity of the lytic principle might have in connection with the question of the living nature of the bacteriophage, we have attempted to study this question further.