Comprehensive Bending Classification of Nucleic Acid Double Helix Structures
Bending classification of helical axis - Circular line (arc)The following tables include structures with 7 or more base pairs given sigma2(arc) is smaller than the corresponding values of the competing models.
Three duplex structures with a small, intermediate, and large radius of curvature and with a different number of base pairs are shown below. More detailed visual and other information for all structures can be obtained from the links given in the Table.
| PDB code | 402d |
1kln |
1am9 |
| image |
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|
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| molecule type | A-RNA duplex | DNA-protein complex (DNA polymerase I, Klenow fragment) |
DNA-protein complex (sterol regulatory element binding protein 1a) |
| radius of curvature | 17.7 Å |
40.2 Å |
141 Å |
| base pairs | 8 |
9 |
38 |
| JPEG | |||
From the values of sigma2 (arc) it can be seen that in most cases an arc is a really good description of the helical axis. The largest goodness of fit values are found for the structures 2d55 (1.207), 402d (1.463), 1d69 (1.693). This is due to a deviation from planarity.
