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DISCUSSION 



POWERS: Wliile discussing the effect of cysteamine on the ESR, observed in 

 albumin following irradiation, you have said that it should be connected appar- 

 ently with the energy transfer and not with the decrease in the number of 

 radicals caused by the transfer of the H-atom from the protector. In this con- 

 nection I have two cjuestions to ask. 



1. What do you mean by "energy transfer"? 



2. How do yovi distinguish it from the reaction of the radicals with the H-atom 

 by means of the ESR spectrum? 



ALEXANDER: We believe that cysteamine does not protect albumin by a repair 

 process because the number of radicals formed (as measiu'ed with ESR) is re- 

 duced even at — 195°C when the bimolecular reaction involved for repair by H 

 transfer cannot occur. 



As to the expression "energy transfer"', these words are used when it is not 

 known why the molecule does not change under some influence. There are many 

 forms of "energy transfer" of this kind. 



POWERS : As regards cysteainine activity at low temperatures it seems to me that 

 the data on the activation energy, available in the literature, indicate that the 



