3D Structure of DNA


Look at the Gal4 transcription factor binding to DNA
OR
λ Cro dimer binding to DNA.

3D Structure of DNA

CPK Color Scheme C O N P
On this page, you can see a double-stranded DNA molecule. While it spins, notice the larger major groove and the smaller minor groove.
Reset and spin this DNA molecule.

Notice the two strands of this DNA molecule.

The two strands of DNA are in opposite orientations so that one chain's 5' phosphate group (yellow) is near the other chain's 3' hydroxyl group (purple).

Look at the backbones for each strand. The backbones are composed of ribose + phosphate + ribose + phosphate.... There are only pale blue nubs where the bases have been deleted for clarity.



Look at the AT base pairs are shown in CPK colors. The backbones are colored by strands and all GC base pairs have been deleted. Hydrogen bonds are shown as dotted lines (even when GC pairs are deleted). How many H-bonds are there between AT base pairs?
Zoom out by using the shift key and mousing up.

Look at the GC base pairs are shown in CPK colors. The backbones are colored by strands and all AT base pairs have been deleted. Hydrogen bonds are shown as dotted lines (even when AT pairs are deleted). How many H-bonds are there between GC base pairs?

Genomics

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