New crystal structures of nucleic acids and their complexes.

In the past year, X-ray crystallographic studies of representatives of all nucleic acid structural types have been reported. Among the most interesting structures are the parallel DNA tetraplex formed by d(TGGGGT), the four-stranded structure formed by d(CCCT) and a double drug bound side by side in an antiparallel orientation to the minor groove of a B-DNA. Certainly, the structure that has received most attention is that of the first complex of a ribozyme with an inhibitor DNA.