CHAPTER 9 



The Problem of Nucleotide Sequence in 

 Deoxyribonucleic Acids'^ 



1 . INTRODUCTION 



Now that some of the most tremendous problems in biochemistry 

 have, it is said, been solved successfully — such as the nature of 

 the genetic material, its structure and mode of replication, and 

 even its biosynthesis — our time, tired of so much exertion, may 

 take a deep breath and then, perhaps, decide that it all has to be 

 done over again. I should not dare contradict, for I have always 

 been more impressed by the enormity of the gap between claim 

 and achievement than by the magnitude of the former. 



In any event, we have set ourselves a much more modest, but 

 by no means easy, task, namely, the elucidation of some of the 

 aspects of the primary structure of deoxyribonucleic acids, 

 especially in regard to the arrangement of the nucleotide con- 

 stituents. In this connection, and since this talk is given in Stock- 

 holm, I may be permitted to recall that it was here, and also in 

 Uppsala, that I had the first opportunity to review our original 

 observations on deoxyribonucleic acid. This is what I said in 

 1949 and what was printed a few months later^. 



". . . The deoxypentose nucleic acids extracted from different species thus 

 appear to be different substances or mixtures of closely related sub- 

 stances of a composition constant for different organs of the same species 

 and characteristic of the species. 



* This chapter has been revised and expanded from a previous publica- 

 tion reprinted with permission from T. W. Goodwin and O. Lindberg 

 (Eds.), Biological Structure and Function, Vol. I, Academic Press, London 

 and New York, 1961, p. 67. 



