The Role of Dissymmetry in the 

 Origin of Living Material 



A. P. TERENT'EV & E. I. KLABUNOVSKIÏ 



Moscow State University {M. V. Lomonosov) and Institute of Organic Chemistry 

 of the Academy of Sciences of the U.S.S.R., Moscow 



Almost ioo years ago Pasteur noticed a characteristic peculiarity of the chemical 

 processes of living nature, namely that they are optically selective. Pasteur stated 

 that this was perhaps the only sharp boundary which can be discerned between 

 the chemistry of dead and living nature. 



TWO FORMULATIONS OF THE QUESTION 



How did there arise, in living protoplasm as it exists to-day, living enzymic 

 systems, with dissymmetrical molecules subserving the optical selectivity of 

 chemical processes ? Many authors hold that the proteins which first came into 

 existence were optically symmetrical and that it was only during the process of 

 evolution that they gradually assumed an optical dissymmetry which was useful 

 in some way, for it is easier to imagine the process of formation of symmetrical 

 proteins than of dissymmetrical ones. This assumes that life can exist without 

 dissymmetry and that symmetrical proteins, being alive, developed dissymmetry, 

 i.e. dissymmetry developed out of symmetry. 



Another view is possible and we will try to substantiate it. We will start from 

 the assumption that life cannot and never could exist without molecular dissymmetry. 

 This means that it is necessary to find an answer, based on some experimental 

 evidence, to two main questions: 



1. What is the biochemical role of molecular dissymmetry? 



2. How could the molecular dissynmietry of the original protoplasm, which 

 led to the development of the living protein-enzymes, have arisen without 

 the intervention of life ? 



THE ESSENTIAL PROPERTIES 



OF OPTICALLY ACTIVE SUBSTANCES: 



THE PASTEUR EFFECT 



The optical activity of organic substances is only one of the manifestations of 

 moleoilar and crystalline dissymmetry. Many other manifestations of dissym- 

 metry may be cited: the piezo effect, triboluminescence, polarized fluorescence. 

 Finally, there are known to exist a large number of crystals which are dissym- 

 metrical in form but do not contain centres of dissymmetry. Among these are 



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