X-ray crystal structure of a locked nucleic acid (LNA) duplex composed of a palindromic 10-mer DNA strand containing one LNA thymine monomer

Locked nucleic acid (LNA), a recently introduced nucleic acid analogue with a bicyclic 2'-O,4'-C-methylene linked furanose sugar, exhibits enhanced affinities for DNA and RNA relative to the corresponding oligodeoxyribonucleotides and oligoribonucleotides; we report the first crystal structure of an LNA unit incorporated in an oligonucleotide duplex. The structure at 1.4 Angstrom resolution of the DNA-LNA decamer duplex with one LNA thymine monomer per strand provides a detailed view of the conformation and hydration of locked nucleic acid residues in a duplex A-form.