The A:T base pair


This is one of two base pairs found in double stranded DNA. Note that both bases are almost in the same plane. To reduce clutter, only the hydrogen atoms near or part of the hydrogen bonds forming the pair are shown. The two phosphorus oxygens not part of the diester backbone are also hidden. The structure seen here is the one found in double stranded DNA. In solution a single base pair would not be stable, and parts of the nucleotides would rotate around each other.

Clicking at the edge of the applet frame will rotate the molecule down in that direction.

Clicking toward the center of the frame will rotate the molecule in the same direction, but at a slower rate.

Clicking in the "zoom In" button will bring the viewer closer, while the "zoom Out" button takes the viewer out from the molecule.

The color scheme for the atoms is standard, except that carbon is black, instead of gray, and hydrogen is dark gray instead of light gray.