136 NUCLEOTIDE SEQUENCE IN DEOXYRIBONUCLEIC ACIDS 



sumably occurs at the broken line A. Since no extraneous sugar 

 fragment is found in ester linkage with the resulting nucleoside 

 diphosphate, a subsequent hydrolysis or elimination must take 

 place at the other flanking sugar (broken line C). It is likely that 

 this cleavage follows a fj aldehyde elimination (broken line B), 

 which has left a double bond between the second and third 

 carbon atom of the sugar. Similar considerations apply to the 



TABLE 28 



DIFFERENTIAL DISTRIBUTION ANALYSIS OF THREE OTHERWISE 

 INDISTINGUISHABLE DEOXYRIBONUCLEIC ACID PREPARATIONS* 



Total 



pyrimidine, 



as mole % P 29.9 20.0 29.9 19.8 30.9 19.6 



Solitary 

 pyrimidine, 

 as mole % of 

 total constitu- 

 ent in DNA 15.9 9.2 19.9 6.3 16.0 14.0 



Solitary or 

 bunched 

 pyrimidines, as 

 mole % P 4.75 1.84 1.72 5.95 1.25 1.71 4.94 2.74 1.66 



Total T/C, 



molar ratio 1.50 1.51 1.58 



Solitary T/C, 



molar ratio 2.58 4.76 1.80 



* The figures are taken from previous papers-i'SC. The deoxyribonucleic 

 acid fractions are described by the molarity of NaCl employed for the 

 dissociation of the histone nucleate^. T designates thymine or thymidylic 

 acid, C cytosine or deoxycytidylic acid, TC the two isomeric dinucleoside 

 triphosphates comprising cytidine and thymidine (reported as moles of 

 dinucleoside triphosphate per 100 gram-atoms of nucleic acid phosphorus). 



