338 PROTEIN POISONS 



serum is inactivated by being heated for one-half hour at 

 55 no poison is formed. Experiments of this kind, as well 

 as those with kaolin already referred to, have led to various 

 suggestions. They have caused many to suspect that the 

 poison comes from the serum. It has been suggested: (a) 

 That the agar or kaolin or bacteria absorbs the complement 

 from the serum and that this renders the serum poisonous. 

 (6) That the poison is preformed in the serum but that its 

 action is neutralized by some other constituent of the serum 

 which is absorbed by the agar or kaolin, (c) That the absorp- 

 tion of some constituent of the serum by the agar, kaolin, or 

 bacteria leads to a disturbance of the equilibrium of the 

 protein constituents of the serum which as a consequence 

 break up with the liberation of the poison. These suggestions 

 assume that the poison comes from the serum, and this 

 may be true. Further experimentation will determine this, 

 but it must be borne in mind that agar contains small 

 amounts of protein, and this has a large surface exposure 

 and is in a physical state most favorable to the action of a 

 proteolytic ferment in the serum. 



Zinsser 1 has shown that the action of complement "upon 

 typhoid bacilli strongly sensitized or not at all sensitized 

 may be carried on, at body temperature, for considerably 

 longer than twelve hours, without leading to a destruction 

 of the poisons, and that this is true when the quantities of 

 the bacteria used vary within the wide range of from one 

 to twelve agar slants. It has been found, in fact, that in 

 the case of this microorganism prolonged exposure at the 

 higher temperature of considerable quantities of bacteria 

 constitute an unfailing method of regularly obtaining power- 

 ful poisons. The results obtained by the use of smaller 

 quantities and the less vigorous action at low temperatures 

 are far less regular or satisfactory." He thinks that his 

 results throw more weight on the assumption that anaphyl- 

 atoxins are responsible to a large extent for the toxemic 

 manifestations of typhoid fever. He also states: "If we 



1 Jour. Exp. Meet., 1913, xvii, 117 



