Salt-induced transition between two double-helical forms of oligo (dC-dG).

The change between a right-handed and a left-handed double-helical structure is certainly an extreme example of the conformational variability of DNA. Studying the energetics and dynamics with defined oligomers provides a convenient way to obtain a quantitative understanding of such processes and can serve as a model for possible regulatory mechanisms in biological systems. Monoclonal antibodies with different specificities to Z-DNA offer a promising technique to search for such structures in more-complicated systems and represent a model system for the quantitative investigation of the interaction of proteins with particular conformations of DNA.