{
  "name": "Helix geometry of the DNA crystal 1BNA: rise, twist and width",
  "desc": "Rise and twist of the 11 base-pair steps of PDB 1BNA, the three axis choices behind the 0.333–0.347 nm band, and the helix width to the phosphorus atoms, the outermost atom centres and the van der Waals surface.",
  "lic": "CC BY 4.0",
  "lic_url": "https://creativecommons.org/licenses/by/4.0/",
  "by": "Ants, Cells & Atoms",
  "url": "https://antscellsandatoms.com/scale/dna-length/",
  "from": [
    "RCSB PDB 1BNA mmCIF coordinates, CC0 (saved copy, 2026-10-25)",
    "PubChem element records 6, 7, 8 and 15, Atomic Radius section (saved responses, 2026-10-25)"
  ],
  "how": "Compiled by Ants, Cells & Atoms from the data listed",
  "data_by": [
    "RCSB PDB 1BNA, CC0, coordinates from Drew HR, Wing RM, Takano T, Broka C, Tanaka S, Itakura K, Dickerson RE 1981, Proceedings of the National Academy of Sciences 78(4):2179–2183, https://doi.org/10.2210/pdb1bna/pdb (retrieved 2026-10-25)",
    "van der Waals radii C 170, N 155, O 152, P 180 pm from PubChem element records 6, 7, 8 and 15 (Los Alamos National Laboratory periodic table), PubChem 2025 update, https://doi.org/10.1093/nar/gkae1059 (retrieved 2026-10-25)",
    "Drew HR et al. 1981, Proceedings of the National Academy of Sciences 78(4):2179–2183, https://doi.org/10.1073/pnas.78.4.2179 (abstract: 36.9 degrees per step, 9.8 base pairs per turn in the central steps; retrieved 2026-10-25)",
    "all other values computed 2026-10-25 for this page"
  ]
}