Watson-Crick edge

FIGURE 4.3 The repeating charges in the backbone force interstrand interactions away from the backbone, causing the strands to make contact at the Watson-Crick edge of the heterocycles. Without the polyanionic backbone, interstrand contacts can be anywhere. X is H in DNA and OH in RNA. 

Based on these data, the existence of solely uncomplexed adenine molecules in the crystal building of the [Mn(/i-ox)(H20)2] (7//-ade) (H2O) compound is not surprising. The nucleobase forms centrosymmetric adenine (H20)2 adenine aggregates (Fig. 16) in which the Watson-Crick edges of each adenine... 

Fig. 2. Watson-Crick, Hoogsteen and sugar edges of RNA bases according to the classification of Leontis and Westhof. In the sugar part of the nucleotides the hydrogen atoms have been removed. Potential H-bond donor/acceptor atoms in the edges are ...

Sponer, ]. E., Spackova, N., Leszczynski, ]., Sponer, 1. (2005b). Principles of RNA base pairing Structures and energies of the trans Watson-Crick/sugar edge base pairs. Journal of Physical Chemistry B, 109,11399. 

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