MOLECULAR CONFIGURATION OF NUCLEIC ACIDS 1 9 



treated as being immersed in water of uniform electron density [3, 4] this 

 discrepancy largely disappears (Fig. 4). 



Preliminary study of sections through all parts of the molecule indicates 

 that the model requires little or no adjustment. This result is not surprising 

 if we assume the water molecule peaks are not spurious, for unless the 



Fig. 5. Scale drawing of Watson-Crick base-pairs [10]. The glycosidic links 

 all make an angle of 38 with the dyacl axis and are equally distant from it. 



positions of the DXA atoms were fairly accurate the synthesis would not 

 have shown these molecules. It is clear, however, that the limited resolving 

 power of the data so far used does not enable the positions of atoms in the 

 base-pair to be distinguished. Therefore the question arises as to whether 

 the atoms in the base-pair might be arranged in some other way which 

 would also correspond with the observed data. 



