290 PROTEIN POISONS 



opinion, it is the poisonous group in the protein molecule, 

 and this is the anaphylactic poison, it matters not what 

 the agent be which has detached it from the other groups. 

 This agent may be wholly chemical, such as we have used 

 in the retort, and it may be any proteolytic ferment, the 

 ferment of the gastric juice, that of a specific or a non- 

 specific serum. As we have stated, since proteolysis consists 

 in the successive and progressive disruption of the protein 

 molecule, in at least one stage of this process, whatever 

 causes it, the protein poison must be released from com- 

 bination with those groups which in the original molecule 

 neutralize it. The sera of many animals, possibly of all, 

 contain proteolytic ferments; some are more active than 

 others; some act upon certain while some act upon other 

 proteins. The products of proteolysis resulting from different 

 ferments certainly differ, and even the poisonous group as 

 detached from the non-poisonous groups by different 

 ferments probably differs in its molecular structure, but 

 the poisonous principle is the same in all cases. Even its 

 physiological action may be slightly modified, though there 

 is no evidence of this, by variation in the lines of cleavage 

 along which the protein molecule is disrupted. The pieces 

 into which the large protein molecule is split depend upon 

 the shape, weight, and force of the hammer that strikes 

 it, and the point where the blow falls. Some of the pieces 

 are large and some small, and when the blow is especially 

 effective the pieces may be so small that the poisonous 

 group is broken and rendered inert; but even when protein 

 is fused with caustic alkali the cyanogen group is still in 

 evidence. 



It seems to us that Friedberger's work has only confirmed 

 our contention, first published in 1907, that the anaphyl- 

 actic poison is the poisonous group in the protein molecule. 

 Friedberger calls his poison "anaphylatoxin." We join 

 Friedemann in protesting against this name. The substance 

 is not a toxin, as we now understand that word. Fried- 

 berger has demonstrated this fact himself, inasmuch as he 

 has shown that his poison does not induce immunity, nor 



