Ultrasonic disintegration as a method of extracting bacterial enzymes.

In recent years several techniques have been developed for the purpose of disintegrating bacterial cells. These have depended upon different principles ranging from autolytic rupture of the cell to grinding with powdered glas (Lipmann, 1938; Koepsell and Johnson, 1942; Wiggert et al., 1940; Kalnitsky et al., 1945; Booth and Green, 1938). Although each method has merit for some specific problem, it frequently proves inadequate for other applications. Of the several methods employed in this laboratory, that of disintegrating bacterial cells by exposure to an ultrasonic field2 has proved of most value when limited quantities of bacteria were available and when the possibility of preparing cell-free enzyme extracts had to be explored. Further, since irradiation of bacteria by ultrasound can be carried out under completely aseptic conditions, it becomes possible to analyze pathogenic bacteria with respect to their endotoxins, enzymes, polysaccharides, and other substances which can be extracted from cells only alter disintegration. The method, however, has two drawbacks: (1) the construction of the apparatus is expensive, and (2) not all bacteria can be disintegrated by ultrasound.