26 



L. F. RETTGER, N. BERMAN AND W. S. STURGES 



of bacteria. The experiments fall into two distinct groups; in 

 the first, tests were made as to the ability of bacteria to digest or 

 destroy their own proteins under highly favorable conditions of 

 temperature and environment. Representative gelatin-hquefy- 

 ing and non-liquefying organisms were employed. The second 

 set of experiments had as its object a study of the fate of purified 

 egg albumin, Witte's peptone, and dialyzed proteoses when added 

 in small amounts to autolyzed bacterial suspensions or to sus- 

 pensions which had the necessary conditions for proteolysis pro- 

 viding the organisms were capable of digesting themselves. 



The different organisms were grown on slant agar and, in a 

 few instances, on potato. The surface growths were washed off 

 with distilled water and transferred to sterile bottles. These 

 suspensions which were of the consistency of a thin paste were 

 incubated at 37 °C. with 5 per cent toluol. Definite amounts of 

 this material were tested from time to time by the quantitative 

 biuret method, a 0.25 per cent solution of peptone being em- 

 ployed as a standard for color comparison. The exact plan of 

 the experiments and the results are given in the following tables. 



TABLE V 

 Autolysis experiments with gelatin-liquefying bacteria 



Note: The above figures are based on the relative strengths of color obtained 

 in the tests, each being compared with the degree of color given by 1.0 cc. of the 

 standard (0.25 per cent) solution of Witte's peptone which is taken as 1.0. In 

 all of the tests 1.0 cc. of the autolysis material was employed. 



