20 PROTEIN POISONS 



its poisonous action through the avidity which it has for 

 the secondary groups of other proteins. These are thus 

 detached from their normal positions and consequently 

 the living protein is deprived of its capability of functioning 

 normally. This is only a theory, but it is one which naturally 

 suggests itself. 



3. The chemical nucleus does not become a poison until 

 stripped in part at least of its secondary groups, and the 

 intensity of its poisonous action is determined by the thorough- 

 ness with which the secondary groups have been removed. 

 The protein molecule may be regarded as a highly complex 

 neutral salt, made up of many basic and acid groups. 

 One of these components, it may be either a basic or an 

 acid group (or it may have within itself both a basic and 

 an acid group), is the chemical nucleus of the molecule. In 

 its natural condition its chemism is satisfied by nicely 

 adjusted combination. When this combination is disrupted, 

 which may be accomplished either by chemical agents or 

 by enzymes, the chemical nucleus is set free, more or less 

 completely, and to the extent that it is released from com- 

 bination, it becomes, in the presence of living proteins, a 

 poison because it disrupts the same. We have shown by 

 direct experiment that the protein poison may be at least 

 partly neutralized by being kept for some days in the 

 presence of an alkaline carbonate at 37 C. 



4. When proteins are submitted to the action of disrupting 

 agents there is the possibility of the chemical nucleus being 

 set free more or less completely, and to the extent that it is 

 detached it becomes a poison. We have found that this 

 occurs when proteins are carefully disrupted by either 

 dilute acid or dilute alkali. So far as our work has gone 

 the best agent with which to disrupt the protein molecule 

 and obtain the largest yield of poison is a 2 per cent, solu- 

 tion of caustic soda in absolute alcohol. This is a crude 

 procedure and much of the poison is destroyed in the 

 process. The disruption easily extends beyond the point 

 where the poison is set free and much of the product sought 

 is destroyed. In peptic digestion the poison becomes active 



