238 PROTEIN POISONS 



the reaction is determined by the chemical constitution of 

 the protein rather than by its biological origin. This is 

 in harmony with the fact that chemically closely related 

 proteins have, as yet, been found only in tissues biologically 

 nearly related. 



"From the results of these experiments it seems probable 

 that the entire protein molecule is not involved in the 

 specific character of the anaphylaxis reaction, but this is 

 developed by certain groups contained therein, and that 

 one and the same protein molecule may contain two or 

 more such groups." 



Evidently the view that the protein molecule contains a 

 sensitizing group, one or more, is finding strong experi- 

 mental support. In our opinion this view was demonstrated 

 by Vaughan and Wheeler 1 as early as 1907, but recent 

 work, such as that by Zunz, Gay, Wells and Osborne, and 

 others, strengthens the evidence then offered. According 

 to our theory every protein molecule contains a chemical 

 nucleus, key-stone or archon. This is the protein poison, 

 and is physiologically much the same in all proteins. One 

 protein differs from another in its secondary or tertiary 

 groups. In these resides the biological specificity of proteins. 

 Biologically related proteins contain chemically related 

 groups, and in these are found the sensitizing agents. The 

 chemical structure of the protein molecule determines its 

 biological differentiation and development. It is not, 

 therefore, surprising to find that a pure protein from wheat 

 sensitizes to another closely related protein from such a 

 biologically closely related grain as rye. This, however, 

 does not indicate that the proteins from the two grains are 

 wholly identical in chemical structure. It only shows that 

 the two protein molecules contain among their secondary 

 groups identical or closely related atomic combinations. 

 The same can be said of the fact that certain non-pathogenic 

 acid-fast bacteria may, at least partially, sensitize animals 

 to the tubercle bacillus. Biological relationship is deter- 



>Jour. Infect. Dis., iv, 476. 



