High-angle neutron fiber diffraction studies of DNA

The technique of neutron high-angle fiber diffraction has been developed and used to undertake isotopic replacement studies on the location of water around the deoxyribonucleic acid (DNA) double helix. The ability to isotopically replace H2O by D2O in fibers of DNA provides a very powerful probe of water structure around this important macromolecule. The results of these experiments are being complemented by X-ray fiber diffraction work on the location of cations around DNA and on the stereochemical pathways followed during conformational changes between the five principal forms that DNA can adopt.