The Comparative Characters of the 



Oxidative Systems of Various Groups of 



Organisms in Relation to Their 



Evolution 



B. A. RUBIN 



A. N. Bakh Institute of Biochemistry of the Academy of Sciences of the U.S.S.R. 

 and Moscow State University, Moscow 



The evidence of contemporary biochemistry shows that many of the properties 

 characteristic of living material are not strictly specific, in that each of them 

 separately is also met with in inorganic nature. 



It must not, however, be ignored that, as well as properties of this sort, there 

 are also attributes which are only present in Hving organisms. Among these 

 attributes we are justified in including the tendency to so-called 'adaptive 

 change', the ability of living bodies to adapt themselves to the conditions of 

 the envirormient in which the development of the organic form in question is 

 taking place. One expression of this specific characteristic of living bodies is 

 their ability to form adaptive enzymes which may be induced by various organic 

 compounds. 



At present material is being accumulated which indicates that physical and 

 chemical faaors such as temperature, light, partial pressure of oxj-gen etc. 

 exert a similar influence on the plant organism. This may be illustrated by 

 examples in connection with the enzymes which catalyse the so-called 'terminal 

 stage' of respiration, namely the oxidation of hydrogen. Nowadays there is 

 nobody who doubts the fact that the oxidative enzymic systems have imdergone 

 prolonged evolution. 



In this connection it is interesting to compare the specific peculiarities of the 

 systems of terminal oxidases in the various groups of organisms which inhabit 

 our planet. Unfortunately there is but little evidence on this question. Further- 

 more, in generalizing about them, one must not ignore the incompleteness of 

 contemporary methods of determining individual oxidases. 



Nevertheless, comparison of the available evidence leads to the conclusion 

 that the peculiarities of the structure of the complex of terminal oxidases is 

 closely associated with the biological specificity of organisms and with the con- 

 ditions under which their tissues carry out the process of respiration. 



It is known that the conditions under which respiration occurs in green plants 

 differ markedly from those in higher forms (warm-blooded) of animals. In the 



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