B-DNA tour
B-form DNAB-form DNA
Source [1] Structural highlights
Take the TourThe tour starts with the view. Now look at this .The backbone is yellow and the bases are magenta. 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. You can also . Each base pair stacks on the next similarly, as shown from . This is the . A-form DNA also stacks in this way, but compare this with Z-DNA, which behaves much differently. DNA is usually found in the B form under physiological conditions. The B-form conformation is stabilized by water molecules bound to the minor groove. You can see them as red dots . Sometimes kinks are found in the B helix at transcriptional control regions. These kinks can either be intrinsic to the DNA sequence or caused by transcription factor binding. You can compare it with the DNA forms by looking at this 3D red-blue stereo picture of A, B, and Z DNA |
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See AlsoSee Also
- Z-DNA model tour and Z-DNA
- A-RNA tour
- A more general overview will be found at DNA.
- Forms of DNA shows a side-by-side comparison of A, B, and Z forms of DNA.
- An interactive tutorial on DNA Structure, disponible también en español and eight other languages.
ReferencesReferences
JSmol in Proteopedia [2] or to the article describing Jmol [3] to the rescue.
- ↑ Dickerson RE, Drew HR, Conner BN, Wing RM, Fratini AV, Kopka ML. The anatomy of A-, B-, and Z-DNA. Science. 1982 Apr 30;216(4545):475-85. PMID:7071593
- ↑ Hanson, R. M., Prilusky, J., Renjian, Z., Nakane, T. and Sussman, J. L. (2013), JSmol and the Next-Generation Web-Based Representation of 3D Molecular Structure as Applied to Proteopedia. Isr. J. Chem., 53:207-216. doi:http://dx.doi.org/10.1002/ijch.201300024
- ↑ Herraez A. Biomolecules in the computer: Jmol to the rescue. Biochem Mol Biol Educ. 2006 Jul;34(4):255-61. doi: 10.1002/bmb.2006.494034042644. PMID:21638687 doi:10.1002/bmb.2006.494034042644