552 WILLIAM S. STURGES AKD LEO F. RETTGER 



that osmosis cannot be excluded as an important factor. Con- 

 radi (1903) described an "autolysis" of Bact. typhosum and 

 Bad. dysenteriae whereby endotoxins were liberated. He be- 

 lieved that all bacteria possess autolytic enzjones. Neisser 

 and Shiga (1903) reported similar observations. They found, 

 however, that the sterile filtrates of twenty-four hour cultures 

 which had been heated at 60°C. for one hour and kept at 37° 

 for two days showed the presence of free "receptors" which had 

 the power of absorbing agglutinins and depressing agglutination. 

 The filtrate from the dysentery bacillus culture was as to:dc as 

 that obtained by Conradi. Hence, in view of this heating, one 

 is not justified in saying that the toxin is liberated by autolysis. 



The autolysis of B. anthracis was described by Levy' and 

 Phersdorff (1902). Microscopic changes were noted in alkaline 

 suspensions to which toluol had been added. Gelatin-liquefy- 

 ing and other enzymes were observed, and the authors claimed 

 that the autolysate was toxic to white mice. However, as 

 much as one thirteenth of the body weight had to be injected 

 in order to obtain these toxicity results. 



Rettger (1904) appUed chemical criteria to the study of the 

 autolysis of microorganisms and pointed out qualitative changes 

 of considerable significance. He noted the liberation of coagu- 

 lable protein and subsequently the formation of leucine and 

 tyrosine in water suspensions of Erythrobacillus prodigiosus. 

 The biuret test was found to be very valuable in following the 

 course of autolysis. Microscopic changes in stained mounts 

 were followed also. During the incubation of water suspensions 

 of Bact. coli to which toluol had been added there was apparently 

 some liberation of coagulable proteins from the cells. It is 

 impossible to state whether this was the result of real autolysis 

 or of osmotic changes. 



In Flexner's study of the meningococcus (1907) the interest- 

 ing observation was made that this organism resists disintegra- 

 tion longer when kept at 37°C. than in the refrigerator. Con- 

 centrated suspensions in physiological sahne solution were found 

 by microscopic examination to undergo rapid autolysis. Woll- 

 stein (1907) showed that the meningococcus and gonococcus 



