Substances Produced in Bacterial Cultures. 49 



28 (1610) 



On certain poisonous substances produced in bacterial cultures. 



By Hans Zinsser, Julia T. Parker and Ann Kuttner. 



[From the Department of Bacteriology, College of Physicians and 

 Surgeons, New York City.] 



In a paper published by one of us last year we called attention 

 to the fact that it was quite likely that not all the toxic substances 

 produced in cultures by bacteria can be peremptorily classified 

 as either exotoxins or endotoxins. The writers working with a 

 number of different organisms, biologically unrelated, have found 

 poisonous substances of moderate potency developed both on 

 fluid and on solid media which they believe should not be regarded 

 at the present time either as specific or antigenic exotoxins, or as 

 endotoxins. Indeed, it seems quite impossible at the present time 

 to definitely classify these substances, for which reason they are 

 referred to in our laboratory, for the present, as the "X" sub- 

 stances. 



I. 



Our first observations on this substance were made with Miss 

 Kuttner on hemolytic streptococci. It was found that super- 

 natent fluids or filtrates of such cultures grown for 20 to 22 hours 

 either aerobically, or better, with partial anaerobiosis, regularly 

 produced sickness in rabbits, although there was great irregularity 

 in potency. Potency was never great. Rabbits intravenously 

 injected with such culture fluids always showed an incubation 

 period of from 60 to 90 minutes, at the end of which time a regular 

 train of symptoms ensued, consisting of respiratory difficulty, 

 weakness, refusal to eat, flattening out on the bottom of the 

 cages, muscular relaxation, half closure and often watering of the 

 eyes, in which condition they either remained for 2 to 3 hours, and 

 then recovered, or in some cases died acutely in anywhere from 

 2 to 3 hours to two days. The dosage necessary for this ranged 

 between 3 and 6 cubic centimeters. It was apparently impossible 

 to control the potency of these substances. We have not found 

 out the reason why, in some cases we obtained very severe symp- 

 toms and death, but in most instances only moderate, but distinct 

 illness. 



