37 



B. Jacobson has studied highly polymer deoxyribose nucleic acid 

 and found that its behavior could be explained better by the as- 

 sumption of "lattice ordered hydration shells" than by the old idea 

 of rotational ellipsoids. The great number of electropolar groups 

 and free charges on this molecule may strongly favor the forma- 

 tion of water structures. Also the fibrous nature favors ice-forma- 

 tion. A globular shape disfavors it, so that it seems likely that 

 mobile globular protein molecules will be found to be built so as 

 to avoid formations of icebergs which would interfere with mo- 

 bility. Since structural proteins are fibrous and closely packed, it 

 seems likely that water, between them, is in a highly ordered state. 

 Bernall and Fowler introduced the idea of "structural tempera- 

 ture" which they defined as the temperature at which free water 

 would have the same degree of order as the water enclosed in the 

 specific system under discussion. We could expect this "structural 

 temperature" to be rather low in protoplasmic formations. The 

 building of such water structures, to use Jacobson's words (1955), 

 "involves a change in physical properties of the whole system 

 qualitatively similar to the changes obtained in the properties of 

 pure water when the temperature is decreased." All this put to- 

 gether means that water, within the cell, may not be random water 

 but "liquid ice" which makes it possible that the triplet states, ob- 

 served on frozen water, also represent the most probable form of 

 excitation in tissues. 



No attempts have been made yet to apply our knowledge of 

 water structures to living systems or to demonstrate triplet excita- 

 tions in biological processes. There are sporadic observations which 

 are suggestive. Gergely (see the author, 1947, p. 101) observed 

 that acridine orange, dissolved in water, showed phosphorescence 

 if actomyosin was added to the solution. The less fibrous myosin 

 or actin were less active. Gergely applied actomyosin in relatively 

 low concentration and so we can expect that at the high protein 

 concentration of muscle triplet excitation would be favored still 

 more. I found that a fresh frog or squid muscle, if suspended in 



