The Z DNA helix
Z-DNA is one of the many possible double helical structures of DNA. It is a left-handed double helical structure in which the double helix winds to the left in a zig-zag pattern (instead of to the right, like the more common B-DNA form). Z-DNA is thought to be one of three biologically active double helical structures along with A- and B-DNA.
Has fewer base pairs per turn than B DNA
Is ored by an alternating GC sequences
Tends to be found at 3 end to genes
Is inhibited by methylation of the bases
Metabolism of nucleic acids