Protein and Protoplasmic Structure 269 



proteins such systems are always found as hydrated chains or chain 

 fragments. Chain parts when coagulated or arranged in micellar 

 fashion do not take part in elastic phenomena. 



If a passively deformed object, for example, a stretched cell, 

 loses its tension, one can conclude, that whole chains slide over each 

 other; therefore, they must be free. If, on the contrary, no relaxa- 

 tion is recognizable, then the protein chains are connected to each 

 other to form a network. 



With this, I come to the matter of contact regions or the region 

 of bonds between molecules in organic jellies. Gelatinized aqueous 

 gelatin and gelatinized starch paste are built in the following man- 

 ner: They consist of a loose network, the regions of contact being 

 formed by micellarly arranged parts of numerous chains held 

 together into a firm bundle. These parts or sections of numerous 

 chains are securely bound by "lattice forces" to form a bundle. 

 Segments of molecules protrude from the micellae ("Fransen- 

 micelle", after Gerngross) which are hydrated and which establish 

 ties between adjoining micelles. As a result, the micelles are united 

 into a network of elastic and solvated molecular threads^. In 

 solutions of high polymeres fewer and smaller regions of contact 

 are sufficient to make an elastic jelly out of a viscous solution. 

 Whether or not gelatinization takes place depends upon the medium, 

 especially its pH, and the presence of electrolytes. Very slight 

 changes in these properties are sufficient to bring about the forma- 

 tion of a jelly. 



I think it not unlikely that such sol-gel changes in protoplasm 

 are to be ascribed to the same factors, acidity and electrolytes, just 

 as in all metabolic changes, such as the synthesis and decomposition 

 of organic acids and acetylcholin, the binding and dissolving of 

 phosphoric acid, etc. 



Editor's Note: The concept which Professor Meyer gives us is 

 so important that I should like to repeat part of his conclusion, and 

 then add a figure. As I did not care to assume the responsibility of 



'Kolloid Zeitschrift, 59, 208. 1932. 

 ° J. Physic. Chem., 34, 2870. 1932. 

 ' Physic. Rev., 39, 857. 1932. 



' Further details in K. H. Meyer "Die hochpolymeren Verbindunsen," Leip- 

 sig. 1940. 



" Helv. chim. acta 20, 1331. 1937. 



