Beschreibung

Construction process

This file was derived from a 3D model of DNA, converted to SVG and coloured using David Eccles' STL2SVG script:

type=orig; ~/scripts/stl2svg.pl ./DNA_linear_complete_helix1.stl:330 ./DNA_linear_complete_helix2.stl:200 ./DNA_linear_complete_${type}_A.stl:140 ./DNA_linear_complete_${type}_C.stl:250 ./DNA_linear_complete_${type}_G.stl:90 ./DNA_linear_complete_${type}_T.stl:30  > out_${type}.svg
type=mut; ~/scripts/stl2svg.pl ./DNA_linear_complete_helix1.stl:330 ./DNA_linear_complete_helix2.stl:200 ./DNA_linear_complete_${type}_A.stl:140 ./DNA_linear_complete_${type}_C.stl:250 ./DNA_linear_complete_${type}_G.stl:90 ./DNA_linear_complete_${type}_T.stl:30  > out_${type}.svg

The DNA models were then combined and annotated using Inkscape. The DNA backbone for the model is a pentagon extruded over a sine wave using David Eccles' guided path extrude script. The model source file (in OpenSCAD format) is shown below:

use <guided_extrude.scad>;

hl = 100; // helix length
hp = 33.2; // helix pitch [in angstroms]
hr = 10; // helix radius [in angstroms]
bbr = 1.5; // backbone radius

loops = hl / hp;

// random bases
//bases = rands(0, 4, ceil(360 * loops / 34.3),1);

// *GRINGENE* -- TAA GGN MGN ATH AAY GGN GAR AAY GAR TGA
//            -- TAA GGC AGG ATC AAC GGC GAG AAC GAG TGA
// A = 0; G = 1; C = 2; T = 3
// [different from my usual order,
//  to simplify the 3D model logic]
bases = [3,3,3, 1,1,2, 0,1,1, 0,3,2, 0,0,2,
         1,1,2, 1,0,1, 0,0,2, 1,0,1, 3,1,0];

bAng = atan2(sin(120) - sin(0), cos(120) - cos(0));

drawMode = "all";

module lineTo(x1, x2){
  hull(){
    translate(x1) sphere(r=0.25, $fn=5);
    translate(x2) sphere(r=0.25, $fn=5);
  }
}

backbone_profile = [for(th = [0:72:359]) [bbr*cos(th),
                                          bbr*sin(th)*1]];

inc = floor($t * 30);
thf = ($t * 30) - inc;
h1limit = (360 * loops);
h1jump = (360 * loops);


helix_1 = [for(th = [(thf*34.3):(34.3/2):h1jump])
  [hr * cos(th), hr * sin(th), hl * th / (360 * loops)]];

helix_2 = [for(th = [120:(34.3/2):(360 * loops+120)])
  [hr * cos(th), hr * sin(th), hl * (th-120) / (360 * loops)]];

module purine(){
  linear_extrude(height=0.75, center=true){
    // average hydrogen bond length in water: 1.97 A
    // https://en.wikipedia.org/wiki/Hydrogen_bond#Structural_details  
    translate([-0.985,0])
      // scale: average of C-C and C=C bond length
      scale(1.435) translate([-2,0]) rotate(12) rotate(18){
        rotate(-30) translate([1,0]) circle(r=1, $fn=6);
        color("blue")
          rotate(36) translate([-1 / (2*sin(36)),0])
            circle(r=1 / (2*sin(36)), $fn=5);
    }
  }
}

module pyrimidine(){
  linear_extrude(height=0.75, center=true){
    // average hydrogen bond length in water: 1.97 A
    // https://en.wikipedia.org/wiki/Hydrogen_bond#Structural_details  
    translate([-0.985,0])
      scale(1.435) translate([-2, 0]) translate([1,0])
         circle(r=1, $fn=6);
  }
}

$vpt = [0, 0, 0];
//$vpr = [310, 105, 10];
$vpr = [0, 0, 0];

rotate([310, 105, 130]) translate([0,0,-hl/2]) {
  if(drawMode == "all" || drawMode == "helix1") color("lightblue")
    mapExtrude("vertCylinder", backbone_profile, helix_1);
  if(drawMode == "all" || drawMode == "helix2") color("pink")
    mapExtrude("vertCylinder", backbone_profile, helix_2);
  for(thb = [inc:(360 * loops / 34.3 + inc)]) {
    thi = thb-inc;
    th = (thi-thf) * 34.3;
    thisBase = bases[floor(thb%30)];
    doPur = (thisBase < 2);
    // base bond has a -1.2° angle;
    // not quite sure how to implement that
    baseFrac = (doPur ? 0.55 : 0.45);
    baseFInv = 1 - baseFrac;
    translate([0,0,hl * th / (360 * loops)]) rotate([-1.2,0,0]){
      if(drawMode == "all" || drawMode == "helix2") color("pink")
        lineTo([hr * cos(th)*(baseFrac-0.15) +
                hr * cos(th+120) * (baseFrac+0.15),
                hr * sin(th)*(baseFrac-0.15) +
                hr * sin(th+120) * (baseFrac+0.15)],
               [hr * cos(th+120), hr * sin(th+120)]);
      if(th < (h1jump))
        if(drawMode == "all" || drawMode == "helix1") color("lightblue")
          lineTo([hr * cos(th), hr * sin(th)],
                 [hr * cos(th)*(baseFrac+0.15) +
                  hr * cos(th+120) * (baseFrac-0.15),
                  hr * sin(th)*(baseFrac+0.15) +
                  hr * sin(th+120) * (baseFrac-0.15)]);
      if(drawMode == "all" ||
         (drawMode == "A" && thisBase == 0) ||
         (drawMode == "G" && thisBase == 1) ||
         (drawMode == "C" && thisBase == 2) ||
         (drawMode == "T" && thisBase == 3)
        )
      color((thisBase < 1) ? "green" : 
            (thisBase < 2) ? "gold"  :
            (thisBase < 3) ? "blue"  :
                             "red")
      translate([hr * cos(th)*baseFrac + hr * cos(th+120) * baseFInv,
                 hr * sin(th)*baseFrac + hr * sin(th+120) * baseFInv])
         rotate(180 + bAng + th) if(doPur) {
            purine(); } else { pyrimidine(); };
      if(drawMode == "all" ||
         (drawMode == "A" && thisBase == 3) ||
         (drawMode == "G" && thisBase == 2) ||
         (drawMode == "C" && thisBase == 1) ||
         (drawMode == "T" && thisBase == 0)
        )
        if(th < (h1jump))
        color((thisBase < 1) ? "red"  : 
              (thisBase < 2) ? "blue" :
              (thisBase < 3) ? "gold" :
                               "green")
        translate([hr * cos(th)*baseFrac + hr * cos(th+120) * baseFInv,
                   hr * sin(th)*baseFrac + hr * sin(th+120) * baseFInv])
           rotate(bAng+th) if(doPur) {
              pyrimidine(); } else { purine(); };
    }
  }
  if(drawMode == "all" || drawMode == "helix1") color("lightblue") {
    translate(helix_1[len(helix_1)-1]) sphere(r=bbr, $fn=5);
    translate(helix_1[0]) sphere(r=bbr, $fn=5);
  }
  if(drawMode == "all" || drawMode == "helix2") color("pink") {
    translate(helix_2[0]) sphere(r=bbr, $fn=5);
    translate(helix_2[len(helix_2)-1]) sphere(r=bbr, $fn=5);
  }
}

Lizenz

Ich, der Urheberrechtsinhaber dieses Werkes, veröffentliche es hiermit unter der folgenden Lizenz:

Es ist erlaubt, die Datei unter den Bedingungen der GNU-Lizenz für freie Dokumentation, Version 1.2 oder einer späteren Version, veröffentlicht von der Free Software Foundation, zu kopieren, zu verbreiten und/oder zu modifizieren; es gibt keine unveränderlichen Abschnitte, keinen vorderen und keinen hinteren Umschlagtext. Der vollständige Text der Lizenz ist im Kapitel GNU-Lizenz für freie Dokumentation verfügbar.http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue

Diese Datei ist lizenziert unter der Creative-Commons-Lizenz „Namensnennung 4.0 international“.

Namensnennung: SNP model by David Eccles (gringer)

Dieses Werk darf von dir

• verbreitet werden – vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden
• neu zusammengestellt werden – abgewandelt und bearbeitet werden

Zu den folgenden Bedingungen:

• Namensnennung – Du musst angemessene Urheber- und Rechteangaben machen, einen Link zur Lizenz beifügen und angeben, ob Änderungen vorgenommen wurden. Diese Angaben dürfen in jeder angemessenen Art und Weise gemacht werden, allerdings nicht so, dass der Eindruck entsteht, der Lizenzgeber unterstütze gerade dich oder deine Nutzung besonders.

https://creativecommons.org/licenses/by/4.0CC BY 4.0 Creative Commons Attribution 4.0 truetrue

Du darfst es unter einer der obigen Lizenzen deiner Wahl verwenden.