Cryo-neutron crystallographic data collection and preliminary refinement of left-handed Z-DNA d(CGCGCG).

ABSTRACT: Crystals of left-handed Z-DNA [d(CGCGCG)]₂ diffract X-rays to beyond 1 Å resolution, feature a small unit cell (∼18 × 31 × 44 Å) and are well hydrated, with around 90 water molecules surrounding the duplex in the asymmetric unit. The duplex shows regular hydration patterns in the narrow minor groove, on the convex surface and around sugar-phosphate backbones. Therefore, Z-DNA offers an ideal case to test the benefits of low-temperature neutron diffraction data collection to potentially determine the donor-acceptor patterns of first- and second-shell water molecules. Nucleic acid fragments pose challenges for neutron crystallography because water molecules are located on the surface rather than inside sequestered spaces such as protein active sites or channels. Water molecules ca

SUBMITTER: Harp JM 

PROVIDER: S-EPMC6168769 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature