CONCLUDING REMARKS 107 



repeating sub-units larger than a mononucleotide. They are com- 

 plicated high polymers of a largely arrhythmic nucleotide sequence 

 which, however, does not appear to be fortuitous^^. 



6. CONCLUDING REMARKS 



It is inviting to assume that the special biological functions of 

 the nucleic acids are reflected in those chemical features that 

 distinguish them from other high-molecular cell components, 

 namely, in the unusual regularities in nucleotide composition 

 mentioned above. In which way these functions are exerted cannot 

 yet be said; but I already have pointed out before that in my 

 opinion the nucleoproteins rather than the separate moieties of 

 the conjugated proteins will eventually be found to be the oper- 

 ative units. A detailed inquiry into the mechanism of this 

 conjunction of protein and nucleic acid, let alone the construc- 

 tion of a reasonable model or the attempt at unraveUing the 

 information code of the cell, is premature; for no truly homo- 

 geneous nucleoprotein has yet been discovered of which it could 

 be said that the particular nucleic acid molecule contained in 

 it, with its unique nucleotide sequence, has given rise to the 

 particular protein, with its equally unique amino acid sequence, 

 or vice versa. In other words, we are still lacking the Rosetta stone 

 of biochemistry. 



It is not profitable to speculate on the direction in which the 

 ancestral roles of the nucleic acids could be approached. But it 

 can be predicted that further investigations along the following 

 lines will be of value: (a) virus nucleoproteins; (b) mechanism of 

 enzyme induction; (c) mechanism of antibody production; (d) 

 role of priming substances in .the enzymic synthesis of high 

 polymers. 



References p. 108 



