B-DNA tour

B-form DNAB-form DNA

Most common DNA conformation in vivo Narrower, more elongated helix than A. Wide major groove easily accessible to proteins Narrow minor groove Favored conformation at high water concentrations (hydration of minor groove seems to favor B-form) Base pairs nearly perpendicular to helix axis Sugar pucker C2'-endo Structural highlights Start the tour with this view. Now look at this .The backbone is yellow and the bases are magenta. You can compare it with the other DNA forms by Note that the major groove (in the middle, when you have just clicked the button) is wide and easily accessible. Now change the display to make it show the connecting the phosphate atoms. Now the bases are easier to see. Notice how they are stacked upon each other and are nearly perpendicular to the axis of the double helix. Note also that the backbone forms a smooth, continuous curve. You can .You are looking into the major groove and the colors of the base pairs alternate. Each base pair stacks on the next similarly, as shown from . A-form DNA also stacks in this way, but compare this with Z-DNA, which behaves much differently. You may include any references to papers as in: the use of JSmol in Proteopedia or to the article describing Jmol to the rescue. Relevance This is a sample scene created with SAT to , and another to make of the protein. You can make your own scenes on SAT starting from scratch or loading and editing one of these sample scenes.

spinqualitylabelsall models B-DNA Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

ReferencesReferences

R. E. Dickerson, H. R. Drew, B. N. Conner, R. M. Wing, A. V. Fratini & M. L. Kopka (1982) The anatomy of A-, B-, and Z-DNA. Science 216: 475-485