Current Problems in Computer Simulation of Variability …
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Fig. 1 Atomic structure and
atom numbering of a DNA
fragment dApdTdGpdC
pyrimidines: thymine, (T), and cytosine, (C). Difference in geometry between purines
(Pur) and pyrimidines (Pyr) is important for the formation of sequence-dependent
three-dimensional structure of DNA.
Nucleic acid strands have directional asymmetry due to non-identical connection of the phosphate group to two deoxyribose moieties. The important feature of
the Watson-Crick duplex (WCD) [1] is the formation of hydrogen bonds (H-bonds)
between the purine from one chain and pyrimidine from the complementary strand;