Major differences include deoxyguanosines in the syn conformation with sugars C3' endo, and deoxycytidines in the anti conformation with sugars C2' endo (i.e., syn and anti refer to the two different orientations of the purine or pyrimidine bases relative to the sugars, and are determined by the torsional angles around the glycosidic bonds, chi). The twist angle relating CpG steps is -8 degrees, while for GpC steps it is -52 degrees; this is associated with large changes in the sugar-phosphate conformation. Finally, dyad axes occur between base pairs, but not at the level of each base pair, since the asymmetric unit in Z-DNA is a base paired dinucleotide.

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