drawtetrado 1.6.0

Draw simplified, layer diagrams of quadruplexes.

Project description

DrawTetrado is a Python application to visualize quadruplexes and G4-helices in DNA and RNA structures. It generates publication-quality SVG files containing layer diagrams. They show the tetrads as a stack, with each position having four nucleobases colored according to anti or syn conformation. In addition, DrawTetrado visualizes the strands with arrows for an accessible overview of their directionality and visual determination of loop types.

DrawTetrado automatically optimizes the layout. The result is a visually pleasing and readable image, even for the most complex cases like V-loops and G4-helices (dimers).

Installation

pip install drawtetrado

Dependencies

The project is written in Python 3.12+ and requires pycairo, svgwrite, and orjson and ElTetrado (Zok et al., 2022; Popenda et al., 2020; Zok et al., 2020). The internal optimization routine is written in C++ and requires Cython and a C++20-compliant compiler (e.g. GCC 8+).

DrawTetrado parses the output of ElTetrado. It can also process PDB or PDBx/mmCIF files which will be first analyzed internally with ElTetrado.

Usage

usage: drawtetrado [-h] [-i INPUT] [-o OUTPUT_TEMPLATE] [--config CONFIG]
                   [-m MODEL] [--no-reorder] [-e [EXTERNAL_FILES ...]]
                   [--tool {fr3d,dssr,rnaview,bpnet,maxit,barnaba,mc-annotate}]

options:
  -h, --help            show this help message and exit
  -i INPUT, --input INPUT
                        path to input PDB, PDBx/mmCIF file or JSON generated
                        by ElTetrado. If PDB or PDBx/mmCIF file is provided,
                        it will be first analyzed using ElTetrado.
  -o OUTPUT_TEMPLATE, --output-template OUTPUT_TEMPLATE
                        (optional) path to output SVG file template
                        [default=input file path and basename]
  --config CONFIG       (optional) JSON config file containing all parameter
                        changes and individual nucleotide coloring overrides
  -m MODEL, --model MODEL
                        (optional, ElTetrado) model number to process
  --no-reorder          (optional, ElTetrado) chains of bi- and tetramolecular
                        quadruplexes should be reordered to be able to have
                        them classified; when this is set, chains will be
                        processed in original order, which for
                        bi-/tetramolecular means that they will likely be
                        misclassified; use with care!
  -e [EXTERNAL_FILES ...], --external-files [EXTERNAL_FILES ...]
                        (optional, ElTetrado) path(s) to external tool output
                        file(s); if omitted ElTetrado will compute
                        interactions itself
  --tool {fr3d,dssr,rnaview,bpnet,maxit,barnaba,mc-annotate}
                        (optional, ElTetrado) name of the external tool that
                        produced the files (auto-detected when not provided)

The output path is a template. Program will generate drawings for each
individual quadruplex in each helix as well as each full helix.If we have a
file with 2 helices with 2 quadruplexes each, if no output_template value is
provided, path and basename of the input file will be used. If it is provided,
output_template=/tmp/out, the resulting files will be /tmp/out_0.svg, with
full helix 0, /tmp/out_0_0.svg and /tmp/out_0_1.svg for each quadruplex in
helix 0. Similar files will be created for helix 1 with /tmp/out_1.svg and
/tmp/out_1_0.svg, /tmp/out_1_1.svg.

Visual customization

DrawTetrado allows for a wide variety of changes to the visual representation of the resulting drawing.

All modifications to visual aspects of the drawing can be done using JSON formatted config file. Example config.json is available in the repository with all possible parameters and their default values.

{
  "_comment0": "Example config.json with all available parameters default values.",
  "_comment1": "All parameters explained in README",

  "scale": 1.0,

  "nucl-longer": 100.0,
  "nucl-shorter": 70.0,
  "nucl-spacing": 10.0,

  "angle": 50.0,
  "tetrad-spacing": 50.0,

  "line-stroke": 3.0,
  "point-size": 6.0,
  "point-stroke": 2.0,

  "se-label-spacing": 20.0,
  "se-label-font-size": 24.0,
  "font-family": "Arial, Helvetica",
  "label-font-size": 20.0,

  "tilted_labels": true,
  "label-chain": true,
  "label-nucl-name": true,
  "label-nucl-fullname": true,
  "label-number": true,

  "_comment2": "Colors in RGBA hex. If only RGB is provided, alpha of 1.0 is used",
  "_comment3": "for anything other than ONZ colors. Those default to 0.85.",
  "colors": {
    "connection": "#000000FF",
    "border": "#E23D28FF",
    "text": "#000000FF",
    "point": "#FFFFFFFF",
    "anti": "#FFFFFFFF",
    "syn": "#000000FF",
    "n/a": "#606060FF",
    "onz_default": "#646464D9",
    "o_plus": "#1F78B4D9",
    "o_minus": "#A6CEE3D9",
    "n_plus": "#33A02CD9",
    "n_minus": "#B2DF8AD9",
    "z_plus": "#FF7F00D9",
    "z_minus": "#FDBF6FD9"
  },

  "_comment3": "dictionary of nucleotide full name to desired color in RGBA hex.",
  "_comment4": "If only RGB is provided, alpha of 0.85 (aka. D9) is used.",
  "_comment_example": "'A.DG12': '#E23D28AA'",
  "nucl-color-override": {}
}

Nucleotide labels are made from 3 parts:

  A.DG12
  A  - Chain of the nucleotide. If label-chain is set to false, this information (and .)
       is not included in the creation of the labels.
  DG - Full name of the nucleotide. Setting label-nucl-fullname to false will result
       in normal short names like A, C, T, G. label-nucl-name to false will remove
       nucleotide name part altogether.
  12 - Index of the nucleotide. Can be removed with label-number set to false.

Examples of how A.DG12 label would look like with different label options:

A.DG12 - Default - All label parameters as true.
A.G12  - "label-nucl-fullname": false
A.12   - "label-nucl-name": false
DG12   - "label-chain": false
A.DG   - "label-number": false
A      - "label-number": false, "label-nucleotide": false

Examples

Human telomere DNA quadruplex

Click to see the input JSON

{
  "metals": [],
  "nucleotides": [
    {
      "index": 1,
      "model": 1,
      "chain": "A",
      "number": 1,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA1",
      "shortName": "A",
      "chi": 22.308,
      "glycosidicBond": "syn"
    },
    {
      "index": 2,
      "model": 1,
      "chain": "A",
      "number": 2,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA2",
      "shortName": "A",
      "chi": -123.055,
      "glycosidicBond": "anti"
    },
    {
      "index": 3,
      "model": 1,
      "chain": "A",
      "number": 3,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA3",
      "shortName": "A",
      "chi": -94.966,
      "glycosidicBond": "anti"
    },
    {
      "index": 4,
      "model": 1,
      "chain": "A",
      "number": 4,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG4",
      "shortName": "G",
      "chi": 79.284,
      "glycosidicBond": "syn"
    },
    {
      "index": 5,
      "model": 1,
      "chain": "A",
      "number": 5,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG5",
      "shortName": "G",
      "chi": -126.017,
      "glycosidicBond": "anti"
    },
    {
      "index": 6,
      "model": 1,
      "chain": "A",
      "number": 6,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG6",
      "shortName": "G",
      "chi": -127.267,
      "glycosidicBond": "anti"
    },
    {
      "index": 7,
      "model": 1,
      "chain": "A",
      "number": 7,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DT7",
      "shortName": "T",
      "chi": -63.108,
      "glycosidicBond": "syn"
    },
    {
      "index": 8,
      "model": 1,
      "chain": "A",
      "number": 8,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DT8",
      "shortName": "T",
      "chi": -138.795,
      "glycosidicBond": "anti"
    },
    {
      "index": 9,
      "model": 1,
      "chain": "A",
      "number": 9,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA9",
      "shortName": "A",
      "chi": -148.84,
      "glycosidicBond": "anti"
    },
    {
      "index": 10,
      "model": 1,
      "chain": "A",
      "number": 10,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG10",
      "shortName": "G",
      "chi": 58.779,
      "glycosidicBond": "syn"
    },
    {
      "index": 11,
      "model": 1,
      "chain": "A",
      "number": 11,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG11",
      "shortName": "G",
      "chi": -123.857,
      "glycosidicBond": "anti"
    },
    {
      "index": 12,
      "model": 1,
      "chain": "A",
      "number": 12,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG12",
      "shortName": "G",
      "chi": -84.367,
      "glycosidicBond": "syn"
    },
    {
      "index": 13,
      "model": 1,
      "chain": "A",
      "number": 13,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DT13",
      "shortName": "T",
      "chi": -30.819,
      "glycosidicBond": "syn"
    },
    {
      "index": 14,
      "model": 1,
      "chain": "A",
      "number": 14,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DT14",
      "shortName": "T",
      "chi": -168.518,
      "glycosidicBond": "anti"
    },
    {
      "index": 15,
      "model": 1,
      "chain": "A",
      "number": 15,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA15",
      "shortName": "A",
      "chi": -105.729,
      "glycosidicBond": "anti"
    },
    {
      "index": 16,
      "model": 1,
      "chain": "A",
      "number": 16,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG16",
      "shortName": "G",
      "chi": 74.323,
      "glycosidicBond": "syn"
    },
    {
      "index": 17,
      "model": 1,
      "chain": "A",
      "number": 17,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG17",
      "shortName": "G",
      "chi": 81.084,
      "glycosidicBond": "syn"
    },
    {
      "index": 18,
      "model": 1,
      "chain": "A",
      "number": 18,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG18",
      "shortName": "G",
      "chi": -122.904,
      "glycosidicBond": "anti"
    },
    {
      "index": 19,
      "model": 1,
      "chain": "A",
      "number": 19,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DT19",
      "shortName": "T",
      "chi": -102.982,
      "glycosidicBond": "anti"
    },
    {
      "index": 20,
      "model": 1,
      "chain": "A",
      "number": 20,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DT20",
      "shortName": "T",
      "chi": -112.151,
      "glycosidicBond": "anti"
    },
    {
      "index": 21,
      "model": 1,
      "chain": "A",
      "number": 21,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA21",
      "shortName": "A",
      "chi": -89.071,
      "glycosidicBond": "syn"
    },
    {
      "index": 22,
      "model": 1,
      "chain": "A",
      "number": 22,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG22",
      "shortName": "G",
      "chi": 83.443,
      "glycosidicBond": "syn"
    },
    {
      "index": 23,
      "model": 1,
      "chain": "A",
      "number": 23,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG23",
      "shortName": "G",
      "chi": -115.412,
      "glycosidicBond": "anti"
    },
    {
      "index": 24,
      "model": 1,
      "chain": "A",
      "number": 24,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG24",
      "shortName": "G",
      "chi": -111.148,
      "glycosidicBond": "anti"
    },
    {
      "index": 25,
      "model": 1,
      "chain": "A",
      "number": 25,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA25",
      "shortName": "A",
      "chi": -58.324,
      "glycosidicBond": "syn"
    },
    {
      "index": 26,
      "model": 1,
      "chain": "A",
      "number": 26,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA26",
      "shortName": "A",
      "chi": -90.841,
      "glycosidicBond": "anti"
    }
  ],
  "basePairs": [
    {
      "nt1": "A.DA2",
      "nt2": "A.DT20",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DT20",
      "nt2": "A.DA2",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA3",
      "nt2": "A.DA21",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DA21",
      "nt2": "A.DA3",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG4",
      "nt2": "A.DT7",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DT7",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG4",
      "nt2": "A.DG10",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG10",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG4",
      "nt2": "A.DG22",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG22",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG5",
      "nt2": "A.DG11",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG11",
      "nt2": "A.DG5",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG5",
      "nt2": "A.DG23",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG23",
      "nt2": "A.DG5",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG6",
      "nt2": "A.DG12",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG12",
      "nt2": "A.DG6",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG6",
      "nt2": "A.DG24",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG24",
      "nt2": "A.DG6",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DT7",
      "nt2": "A.DG10",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.DG10",
      "nt2": "A.DT7",
      "stericity": "cis",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG10",
      "nt2": "A.DG18",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG18",
      "nt2": "A.DG10",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG11",
      "nt2": "A.DG17",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG17",
      "nt2": "A.DG11",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG12",
      "nt2": "A.DG16",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG16",
      "nt2": "A.DG12",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DT14",
      "nt2": "A.DA25",
      "stericity": "trans",
      "edge5": "Watson-Crick",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DA25",
      "nt2": "A.DT14",
      "stericity": "trans",
      "edge5": "Watson-Crick",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DA15",
      "nt2": "A.DA25",
      "stericity": "trans",
      "edge5": "Sugar",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DA25",
      "nt2": "A.DA15",
      "stericity": "trans",
      "edge5": "Watson-Crick",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.DG16",
      "nt2": "A.DG24",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG24",
      "nt2": "A.DG16",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG17",
      "nt2": "A.DG23",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG23",
      "nt2": "A.DG17",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG18",
      "nt2": "A.DG22",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG22",
      "nt2": "A.DG18",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    }
  ],
  "helices": [
    {
      "quadruplexes": [
        {
          "tetrads": [
            {
              "id": "A.DG6-A.DG12-A.DG16-A.DG24",
              "nt1": "A.DG6",
              "nt2": "A.DG12",
              "nt3": "A.DG16",
              "nt4": "A.DG24",
              "onz": "O+",
              "gbaClassification": "VIa",
              "planarityDeviation": 0.1829350977806063,
              "ionsChannel": [],
              "ionsOutside": []
            },
            {
              "id": "A.DG5-A.DG11-A.DG17-A.DG23",
              "nt1": "A.DG5",
              "nt2": "A.DG11",
              "nt3": "A.DG17",
              "nt4": "A.DG23",
              "onz": "O+",
              "gbaClassification": "Va",
              "planarityDeviation": 0.10474313820007491,
              "ionsChannel": [],
              "ionsOutside": []
            },
            {
              "id": "A.DG4-A.DG22-A.DG18-A.DG10",
              "nt1": "A.DG4",
              "nt2": "A.DG22",
              "nt3": "A.DG18",
              "nt4": "A.DG10",
              "onz": "O-",
              "gbaClassification": "Vb",
              "planarityDeviation": 0.17372283960377813,
              "ionsChannel": [],
              "ionsOutside": []
            }
          ],
          "onzm": "Oh*",
          "loopClassification": "9a",
          "gbaClassification": ["V", "VI"],
          "tracts": [
            ["A.DG16", "A.DG17", "A.DG18"],
            ["A.DG24", "A.DG23", "A.DG22"],
            ["A.DG6", "A.DG5", "A.DG4"],
            ["A.DG12", "A.DG11", "A.DG10"]
          ],
          "loops": [
            {
              "type": "propeller-",
              "nucleotides": ["A.DT7", "A.DT8", "A.DA9"]
            },
            {
              "type": "lateral-",
              "nucleotides": ["A.DT13", "A.DT14", "A.DA15"]
            },
            {
              "type": "lateral+",
              "nucleotides": ["A.DT19", "A.DT20", "A.DA21"]
            }
          ]
        }
      ],
      "tetradPairs": [
        {
          "tetrad1": "A.DG6-A.DG12-A.DG16-A.DG24",
          "tetrad2": "A.DG5-A.DG11-A.DG17-A.DG23",
          "direction": "hybrid",
          "rise": 3.1149939255558747,
          "twist": 27.111587838260725
        },
        {
          "tetrad1": "A.DG5-A.DG11-A.DG17-A.DG23",
          "tetrad2": "A.DG4-A.DG22-A.DG18-A.DG10",
          "direction": "hybrid",
          "rise": 3.2109650905140654,
          "twist": 20.409525129779524
        }
      ]
    }
  ]
}

V-loop

Click to see the input JSON

{
  "metals": [],
  "nucleotides": [
    {
      "index": 1,
      "model": 1,
      "chain": "A",
      "number": 1,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG1",
      "shortName": "G",
      "chi": 54.111,
      "glycosidicBond": "syn"
    },
    {
      "index": 2,
      "model": 1,
      "chain": "A",
      "number": 2,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG2",
      "shortName": "G",
      "chi": 83.093,
      "glycosidicBond": "syn"
    },
    {
      "index": 3,
      "model": 1,
      "chain": "A",
      "number": 3,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG3",
      "shortName": "G",
      "chi": -120.17,
      "glycosidicBond": "anti"
    },
    {
      "index": 4,
      "model": 1,
      "chain": "A",
      "number": 4,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA4",
      "shortName": "A",
      "chi": -111.874,
      "glycosidicBond": "anti"
    },
    {
      "index": 5,
      "model": 1,
      "chain": "A",
      "number": 5,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DT5",
      "shortName": "T",
      "chi": -153.281,
      "glycosidicBond": "anti"
    },
    {
      "index": 6,
      "model": 1,
      "chain": "A",
      "number": 6,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG6",
      "shortName": "G",
      "chi": -106.483,
      "glycosidicBond": "anti"
    },
    {
      "index": 7,
      "model": 1,
      "chain": "A",
      "number": 7,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG7",
      "shortName": "G",
      "chi": -122.668,
      "glycosidicBond": "anti"
    },
    {
      "index": 8,
      "model": 1,
      "chain": "A",
      "number": 8,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG8",
      "shortName": "G",
      "chi": -125.241,
      "glycosidicBond": "anti"
    },
    {
      "index": 9,
      "model": 1,
      "chain": "A",
      "number": 9,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA9",
      "shortName": "A",
      "chi": -90.027,
      "glycosidicBond": "anti"
    },
    {
      "index": 10,
      "model": 1,
      "chain": "A",
      "number": 10,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DC10",
      "shortName": "C",
      "chi": -144.141,
      "glycosidicBond": "anti"
    },
    {
      "index": 11,
      "model": 1,
      "chain": "A",
      "number": 11,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA11",
      "shortName": "A",
      "chi": -139.299,
      "glycosidicBond": "anti"
    },
    {
      "index": 12,
      "model": 1,
      "chain": "A",
      "number": 12,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DC12",
      "shortName": "C",
      "chi": -89.925,
      "glycosidicBond": "syn"
    },
    {
      "index": 13,
      "model": 1,
      "chain": "A",
      "number": 13,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA13",
      "shortName": "A",
      "chi": -116.926,
      "glycosidicBond": "anti"
    },
    {
      "index": 14,
      "model": 1,
      "chain": "A",
      "number": 14,
      "icode": " ",
      "molecule": "Other",
      "fullName": "A.GF2/14",
      "shortName": "g",
      "chi": 75.041,
      "glycosidicBond": "syn"
    },
    {
      "index": 15,
      "model": 1,
      "chain": "A",
      "number": 15,
      "icode": " ",
      "molecule": "Other",
      "fullName": "A.GFL15",
      "shortName": "g",
      "chi": -167.524,
      "glycosidicBond": "anti"
    },
    {
      "index": 16,
      "model": 1,
      "chain": "A",
      "number": 16,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG16",
      "shortName": "G",
      "chi": -100.43,
      "glycosidicBond": "anti"
    },
    {
      "index": 17,
      "model": 1,
      "chain": "A",
      "number": 17,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG17",
      "shortName": "G",
      "chi": -140.143,
      "glycosidicBond": "anti"
    },
    {
      "index": 18,
      "model": 1,
      "chain": "A",
      "number": 18,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA18",
      "shortName": "A",
      "chi": -100.903,
      "glycosidicBond": "anti"
    },
    {
      "index": 19,
      "model": 1,
      "chain": "A",
      "number": 19,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DC19",
      "shortName": "C",
      "chi": -131.147,
      "glycosidicBond": "anti"
    },
    {
      "index": 20,
      "model": 1,
      "chain": "A",
      "number": 20,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG20",
      "shortName": "G",
      "chi": -169.165,
      "glycosidicBond": "anti"
    },
    {
      "index": 21,
      "model": 1,
      "chain": "A",
      "number": 21,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG21",
      "shortName": "G",
      "chi": -105.18,
      "glycosidicBond": "anti"
    },
    {
      "index": 22,
      "model": 1,
      "chain": "A",
      "number": 22,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG22",
      "shortName": "G",
      "chi": -106.1,
      "glycosidicBond": "anti"
    }
  ],
  "basePairs": [
    {
      "nt1": "A.DG1",
      "nt2": "A.DG7",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG7",
      "nt2": "A.DG1",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG1",
      "nt2": "A.DG16",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG16",
      "nt2": "A.DG1",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG2",
      "nt2": "A.DG6",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG6",
      "nt2": "A.DG2",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG2",
      "nt2": "A.GFL15",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.GFL15",
      "nt2": "A.DG2",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG3",
      "nt2": "A.DG6",
      "stericity": "cis",
      "edge5": "Sugar",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG6",
      "nt2": "A.DG3",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.DG3",
      "nt2": "A.DG20",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG20",
      "nt2": "A.DG3",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG6",
      "nt2": "A.DG20",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG20",
      "nt2": "A.DG6",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG7",
      "nt2": "A.DG21",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG21",
      "nt2": "A.DG7",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG8",
      "nt2": "A.GF2/14",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.GF2/14",
      "nt2": "A.DG8",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG8",
      "nt2": "A.DG22",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG22",
      "nt2": "A.DG8",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DC12",
      "nt2": "A.DA13",
      "stericity": "cis",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA13",
      "nt2": "A.DC12",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.GF2/14",
      "nt2": "A.DG17",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG17",
      "nt2": "A.GF2/14",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.GFL15",
      "nt2": "A.DG20",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG20",
      "nt2": "A.GFL15",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG16",
      "nt2": "A.DA18",
      "stericity": "trans",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA18",
      "nt2": "A.DG16",
      "stericity": "trans",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.DG16",
      "nt2": "A.DG21",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG21",
      "nt2": "A.DG16",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG17",
      "nt2": "A.DG22",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG22",
      "nt2": "A.DG17",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    }
  ],
  "helices": [
    {
      "quadruplexes": [
        {
          "tetrads": [
            {
              "id": "A.DG2-A.GFL15-A.DG20-A.DG6",
              "nt1": "A.DG2",
              "nt2": "A.GFL15",
              "nt3": "A.DG20",
              "nt4": "A.DG6",
              "onz": "N-",
              "gbaClassification": "VIIb",
              "planarityDeviation": 0.2180730955436729,
              "ionsChannel": [],
              "ionsOutside": []
            },
            {
              "id": "A.DG1-A.DG16-A.DG21-A.DG7",
              "nt1": "A.DG1",
              "nt2": "A.DG16",
              "nt3": "A.DG21",
              "nt4": "A.DG7",
              "onz": "N-",
              "gbaClassification": "VIIb",
              "planarityDeviation": 0.23623267132215198,
              "ionsChannel": [],
              "ionsOutside": []
            },
            {
              "id": "A.DG8-A.GF2/14-A.DG17-A.DG22",
              "nt1": "A.DG8",
              "nt2": "A.GF2/14",
              "nt3": "A.DG17",
              "nt4": "A.DG22",
              "onz": "O+",
              "gbaClassification": "IIIa",
              "planarityDeviation": 0.12292426530184954,
              "ionsChannel": [],
              "ionsOutside": []
            }
          ],
          "onzm": "Mh*",
          "loopClassification": "7b",
          "gbaClassification": ["III", "VII"],
          "tracts": [
            ["A.DG20", "A.DG21", "A.DG22"],
            ["A.DG6", "A.DG7", "A.DG8"],
            ["A.DG2", "A.DG1", "A.GF2/14"],
            ["A.GFL15", "A.DG16", "A.DG17"]
          ],
          "loops": [
            {
              "type": "lateral+",
              "nucleotides": ["A.DG3", "A.DA4", "A.DT5"]
            },
            {
              "type": "lateral-",
              "nucleotides": ["A.DA9", "A.DC10", "A.DA11", "A.DC12", "A.DA13"]
            },
            {
              "type": "propeller-",
              "nucleotides": ["A.DA18", "A.DC19"]
            }
          ]
        }
      ],
      "tetradPairs": [
        {
          "tetrad1": "A.DG2-A.GFL15-A.DG20-A.DG6",
          "tetrad2": "A.DG1-A.DG16-A.DG21-A.DG7",
          "direction": "hybrid",
          "rise": 3.4053905200064882,
          "twist": 32.09137702765124
        },
        {
          "tetrad1": "A.DG1-A.DG16-A.DG21-A.DG7",
          "tetrad2": "A.DG8-A.GF2/14-A.DG17-A.DG22",
          "direction": "parallel",
          "rise": 3.4862467282164604,
          "twist": 29.215089333872314
        }
      ]
    }
  ]
}

G4-helix (dimer)

Click to see the input JSON

{
  "metals": [],
  "nucleotides": [
    {
      "index": 1,
      "model": 1,
      "chain": "A",
      "number": 1,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG1",
      "shortName": "G",
      "chi": -109.42,
      "glycosidicBond": "anti"
    },
    {
      "index": 2,
      "model": 1,
      "chain": "A",
      "number": 2,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG2",
      "shortName": "G",
      "chi": -128.871,
      "glycosidicBond": "anti"
    },
    {
      "index": 3,
      "model": 1,
      "chain": "A",
      "number": 3,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA3",
      "shortName": "A",
      "chi": -56.59,
      "glycosidicBond": "syn"
    },
    {
      "index": 4,
      "model": 1,
      "chain": "A",
      "number": 4,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG4",
      "shortName": "G",
      "chi": -171.001,
      "glycosidicBond": "anti"
    },
    {
      "index": 5,
      "model": 1,
      "chain": "A",
      "number": 5,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG5",
      "shortName": "G",
      "chi": -127.906,
      "glycosidicBond": "anti"
    },
    {
      "index": 6,
      "model": 1,
      "chain": "A",
      "number": 6,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA6",
      "shortName": "A",
      "chi": -87.061,
      "glycosidicBond": "syn"
    },
    {
      "index": 7,
      "model": 1,
      "chain": "A",
      "number": 7,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG7",
      "shortName": "G",
      "chi": -159.577,
      "glycosidicBond": "anti"
    },
    {
      "index": 8,
      "model": 1,
      "chain": "A",
      "number": 8,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG8",
      "shortName": "G",
      "chi": -135.751,
      "glycosidicBond": "anti"
    },
    {
      "index": 9,
      "model": 1,
      "chain": "A",
      "number": 9,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA9",
      "shortName": "A",
      "chi": -50.982,
      "glycosidicBond": "syn"
    },
    {
      "index": 10,
      "model": 1,
      "chain": "A",
      "number": 10,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG10",
      "shortName": "G",
      "chi": -135.29,
      "glycosidicBond": "anti"
    },
    {
      "index": 11,
      "model": 1,
      "chain": "A",
      "number": 11,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DG11",
      "shortName": "G",
      "chi": -113.575,
      "glycosidicBond": "anti"
    },
    {
      "index": 12,
      "model": 1,
      "chain": "A",
      "number": 12,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "A.DA12",
      "shortName": "A",
      "chi": -110.595,
      "glycosidicBond": "anti"
    },
    {
      "index": 13,
      "model": 1,
      "chain": "B",
      "number": 13,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG13",
      "shortName": "G",
      "chi": -112.685,
      "glycosidicBond": "anti"
    },
    {
      "index": 14,
      "model": 1,
      "chain": "B",
      "number": 14,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG14",
      "shortName": "G",
      "chi": -136.989,
      "glycosidicBond": "anti"
    },
    {
      "index": 15,
      "model": 1,
      "chain": "B",
      "number": 15,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DA15",
      "shortName": "A",
      "chi": -57.076,
      "glycosidicBond": "syn"
    },
    {
      "index": 16,
      "model": 1,
      "chain": "B",
      "number": 16,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG16",
      "shortName": "G",
      "chi": -169.156,
      "glycosidicBond": "anti"
    },
    {
      "index": 17,
      "model": 1,
      "chain": "B",
      "number": 17,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG17",
      "shortName": "G",
      "chi": -124.27,
      "glycosidicBond": "anti"
    },
    {
      "index": 18,
      "model": 1,
      "chain": "B",
      "number": 18,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DA18",
      "shortName": "A",
      "chi": -84.463,
      "glycosidicBond": "syn"
    },
    {
      "index": 19,
      "model": 1,
      "chain": "B",
      "number": 19,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG19",
      "shortName": "G",
      "chi": -164.508,
      "glycosidicBond": "anti"
    },
    {
      "index": 20,
      "model": 1,
      "chain": "B",
      "number": 20,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG20",
      "shortName": "G",
      "chi": -141.652,
      "glycosidicBond": "anti"
    },
    {
      "index": 21,
      "model": 1,
      "chain": "B",
      "number": 21,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DA21",
      "shortName": "A",
      "chi": -59.955,
      "glycosidicBond": "syn"
    },
    {
      "index": 22,
      "model": 1,
      "chain": "B",
      "number": 22,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG22",
      "shortName": "G",
      "chi": -128.818,
      "glycosidicBond": "anti"
    },
    {
      "index": 23,
      "model": 1,
      "chain": "B",
      "number": 23,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DG23",
      "shortName": "G",
      "chi": -108.407,
      "glycosidicBond": "anti"
    },
    {
      "index": 24,
      "model": 1,
      "chain": "B",
      "number": 24,
      "icode": " ",
      "molecule": "DNA",
      "fullName": "B.DA24",
      "shortName": "A",
      "chi": -115.199,
      "glycosidicBond": "anti"
    }
  ],
  "basePairs": [
    {
      "nt1": "A.DG1",
      "nt2": "A.DA3",
      "stericity": "trans",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA3",
      "nt2": "A.DG1",
      "stericity": "trans",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.DG1",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG4",
      "nt2": "A.DG1",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG1",
      "nt2": "A.DG10",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG10",
      "nt2": "A.DG1",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG2",
      "nt2": "A.DG5",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG5",
      "nt2": "A.DG2",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG2",
      "nt2": "A.DG11",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG11",
      "nt2": "A.DG2",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG2",
      "nt2": "A.DA12",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DA12",
      "nt2": "A.DG2",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA3",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG4",
      "nt2": "A.DA3",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG4",
      "nt2": "A.DA6",
      "stericity": "cis",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA6",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.DG4",
      "nt2": "A.DG7",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG7",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG4",
      "nt2": "B.DG22",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG22",
      "nt2": "A.DG4",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG5",
      "nt2": "A.DG8",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG8",
      "nt2": "A.DG5",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DA6",
      "nt2": "A.DG7",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG7",
      "nt2": "A.DA6",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG7",
      "nt2": "A.DA9",
      "stericity": "trans",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA9",
      "nt2": "A.DG7",
      "stericity": "trans",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "A.DG7",
      "nt2": "A.DG10",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG10",
      "nt2": "A.DG7",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG8",
      "nt2": "A.DG11",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG11",
      "nt2": "A.DG8",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG8",
      "nt2": "A.DA12",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DA12",
      "nt2": "A.DG8",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "A.DG10",
      "nt2": "B.DG16",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG16",
      "nt2": "A.DG10",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "A.DG10",
      "nt2": "B.DG22",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG22",
      "nt2": "A.DG10",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG13",
      "nt2": "B.DA15",
      "stericity": "trans",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DA15",
      "nt2": "B.DG13",
      "stericity": "trans",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "B.DG13",
      "nt2": "B.DG16",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG16",
      "nt2": "B.DG13",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG13",
      "nt2": "B.DG22",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG22",
      "nt2": "B.DG13",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG14",
      "nt2": "B.DG17",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG17",
      "nt2": "B.DG14",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG14",
      "nt2": "B.DG23",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG23",
      "nt2": "B.DG14",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG14",
      "nt2": "B.DA24",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DA24",
      "nt2": "B.DG14",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DA15",
      "nt2": "B.DG16",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG16",
      "nt2": "B.DA15",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG16",
      "nt2": "B.DA18",
      "stericity": "cis",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DA18",
      "nt2": "B.DG16",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "B.DG16",
      "nt2": "B.DG19",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG19",
      "nt2": "B.DG16",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG17",
      "nt2": "B.DG20",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG20",
      "nt2": "B.DG17",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DA18",
      "nt2": "B.DG19",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG19",
      "nt2": "B.DA18",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG19",
      "nt2": "B.DA21",
      "stericity": "trans",
      "edge5": "Sugar",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DA21",
      "nt2": "B.DG19",
      "stericity": "trans",
      "edge5": "Hoogsteen",
      "edge3": "Sugar"
    },
    {
      "nt1": "B.DG19",
      "nt2": "B.DG22",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG22",
      "nt2": "B.DG19",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    },
    {
      "nt1": "B.DG20",
      "nt2": "B.DG23",
      "stericity": "cis",
      "edge5": "Watson-Crick",
      "edge3": "Hoogsteen"
    },
    {
      "nt1": "B.DG23",
      "nt2": "B.DG20",
      "stericity": "cis",
      "edge5": "Hoogsteen",
      "edge3": "Watson-Crick"
    }
  ],
  "helices": [
    {
      "quadruplexes": [
        {
          "tetrads": [
            {
              "id": "B.DG14-B.DG17-B.DG20-B.DG23",
              "nt1": "B.DG14",
              "nt2": "B.DG17",
              "nt3": "B.DG20",
              "nt4": "B.DG23",
              "onz": "O+",
              "gbaClassification": "VIIIa",
              "planarityDeviation": 0.16023147318800904,
              "ionsChannel": [],
              "ionsOutside": []
            },
            {
              "id": "B.DG13-B.DG16-B.DG19-B.DG22",
              "nt1": "B.DG13",
              "nt2": "B.DG16",
              "nt3": "B.DG19",
              "nt4": "B.DG22",
              "onz": "O+",
              "gbaClassification": "VIIIa",
              "planarityDeviation": 0.45582726991701444,
              "ionsChannel": [],
              "ionsOutside": []
            }
          ],
          "onzm": "Op+",
          "loopClassification": "1a",
          "gbaClassification": ["VIII"],
          "tracts": [
            ["B.DG23", "B.DG22"],
            ["B.DG14", "B.DG13"],
            ["B.DG17", "B.DG16"],
            ["B.DG20", "B.DG19"]
          ],
          "loops": [
            {
              "type": "propeller-",
              "nucleotides": ["B.DA15"]
            },
            {
              "type": "propeller-",
              "nucleotides": ["B.DA18"]
            },
            {
              "type": "propeller-",
              "nucleotides": ["B.DA21"]
            }
          ]
        },
        {
          "tetrads": [
            {
              "id": "A.DG1-A.DG4-A.DG7-A.DG10",
              "nt1": "A.DG1",
              "nt2": "A.DG4",
              "nt3": "A.DG7",
              "nt4": "A.DG10",
              "onz": "O+",
              "gbaClassification": "VIIIa",
              "planarityDeviation": 0.5675509888987945,
              "ionsChannel": [],
              "ionsOutside": []
            },
            {
              "id": "A.DG2-A.DG5-A.DG8-A.DA12",
              "nt1": "A.DG2",
              "nt2": "A.DG5",
              "nt3": "A.DG8",
              "nt4": "A.DA12",
              "onz": "O+",
              "gbaClassification": "VIIIa",
              "planarityDeviation": 0.7820234571290057,
              "ionsChannel": [],
              "ionsOutside": []
            }
          ],
          "onzm": "Op+",
          "loopClassification": "1a",
          "gbaClassification": ["VIII"],
          "tracts": [
            ["A.DG7", "A.DG8"],
            ["A.DG10", "A.DA12"],
            ["A.DG1", "A.DG2"],
            ["A.DG4", "A.DG5"]
          ],
          "loops": [
            {
              "type": "propeller-",
              "nucleotides": ["A.DA3"]
            },
            {
              "type": "propeller-",
              "nucleotides": ["A.DA6"]
            },
            {
              "type": "propeller-",
              "nucleotides": ["A.DA9"]
            }
          ]
        }
      ],
      "tetradPairs": [
        {
          "tetrad1": "B.DG14-B.DG17-B.DG20-B.DG23",
          "tetrad2": "B.DG13-B.DG16-B.DG19-B.DG22",
          "direction": "parallel",
          "rise": 3.4598098620083153,
          "twist": 26.65295578601502
        },
        {
          "tetrad1": "B.DG13-B.DG16-B.DG19-B.DG22",
          "tetrad2": "A.DG1-A.DG4-A.DG7-A.DG10",
          "direction": "parallel",
          "rise": 3.1498276292124316,
          "twist": 7.769329062763674
        },
        {
          "tetrad1": "A.DG1-A.DG4-A.DG7-A.DG10",
          "tetrad2": "A.DG2-A.DG5-A.DG8-A.DA12",
          "direction": "parallel",
          "rise": 4.363977409213413,
          "twist": 53.69239641441069
        }
      ]
    }
  ]
}

Bibliography

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