SPECIFIC POLYHYDROXY COMPOUNDS AS 



COFACTORS OF ENZYMIC ADAPTATION AND 



ITS INHERITANCE 



P. P. Slonimski and H. de Robichon-Szulmajster 



Laboratoire de Genetique Physiologique du CNRS, Gif-sur- Yvette 



It is a part of the definition of the word "truism", and not 

 the least important one, that it is accepted as something self- 

 evident. A truism probably as old as genetics is the one 

 exemplified by the following quotation from a well known 

 textbook: "The most important property of a gene is that it 

 reproduces itself, that is, forms a copy of itself from material 

 present in the cell. Furthermore, genes may form and give ofP 

 substances which influence specific reactions, first within the 

 cell and subsequently elsewhere in the organism. These two 

 properties or functions of genes, that of autocatalysis and of 

 heterocatalysis, may prove to be two aspects of the same 

 process : the specific gene products given off* in the cell may be 

 merely byproducts of the reactions of gene synthesis" (Sinnot, 

 Dunn and Dobzhansky, 1950). This statement applies not 

 only to genes but to all types of genetic material whether 

 nuclear or cytoplasmic. According to the authors' preferences, 

 the autocatalytic function is referred to as autoreproduction, 

 self-duplication, copying, covariant replication or transmission 

 of information, most probably from nucleic acid to nucleic 

 acid, while the heterocatalytic function is generally described 

 as control, determinism or information transfer from nucleic 

 acid to proteins and enzymes in particular. A purely formal 

 scheme can represent these two functions: 



NA ► NA — >► NA >► 



I > I 



I ■ I 



I y V 



Enzyme Enzyme Enzyme 

 210 



