Direct interactions between Z-DNA and alkaline earth cations, discovered in the presence of high concentrations of MgCl2 and CaCl2

In the presence of high concentration of MgCl2, two Mg2 + cations were bonded directly to two phosphate groups of Z-DNA duplexes. The direct interactions achieved adhesion of neighboring Z-DNA duplexes to build the hexagonal assembly of the Z-DNA duplexes.