The Action of Glycine on Bacterial Suspensions *

In the course of some experimental work it was noticed that the addition of glycine to broth cultures or aqueous suspensions of bacteria resulted, after some hours, in the apparent lysis of the cells. Closer examination of the phenomenon revealed that the first visible action was an immediate increase in the turbidity of the cell suspension, depending in degree upon the concentration of the glycine. This initial turbidity increase was followed by a slow and progressive decrease in turbidity, until, after some hours, the cloudiness of the suspension, provided too many cells had not been added, had entirely vanished. With heavy suspensions of cells complete clarification is not obtained. Although Escherichia coli and Bacillus mesentericus have been used in most of the work, all of the species of bacteria examined have proved susceptible. Curiously, the pneumococcus lyses slowly, as is the rule with other species, and does not dissolve almost at once as it does in bile.