Protoplasmic Structure 39 



(4) Indirect union of alpha carbon to alpha 

 carbon by means of the — CH 2 — S — S — CH 2 — 

 group, as evidenced by cystine. 



The above conclusions were arrived at on the 

 assumption that protein nitrogen occurs only in 

 the spirazines. There is no evidence that it 

 occurs anywhere else, and the amount of nitrogen 

 that is present in the spirazines alone is too much 

 rather than too little to satisfy the percentage 

 composition of proteins as found experimentally. 

 The two amino groups of arginine, ornithine, and 

 lysine were therefore assumed to have come from 

 adjacent spirazines. 



The hydrocarbon side chains of amino acids 

 exhibit frequent branching at the beta and gamma 

 carbon atoms, as in the case of valine, isoleucine, 

 leucine, phenylalanine, and tyrosine. Such branch- 

 ing, at first glance, suggests triple junctions be- 

 tween three adjacent spirazines as shown in Fig. 2. 

 Such triple junctions would undoubtedly be chemi- 

 cally stable and will fit together nicely to form 

 hexagonal compartments as shown in Fig. 3, which 

 would probably be able to grow and perpetuate 

 themselves if they actually existed. However, if 

 such structures exist in nature, then the decompo- 

 sition products of protoplasmic substances ought 

 to contain tri-amino or tri-carboxylic acids or 



