Nucleic Acids in Chemistry and Biology
28 Chapter 2 Figure 2.19 Diagrams illustrating movements of bases in sequence-dependent structures. Rows (a) to (c) show local r ...
DNA and RNA Structure 29 Table 2.3 Average helix parameters for the major DNA conformations Helix Residues Twist per Displacemen ...
30 Chapter 2 can be appreciated from the 3D picture of the helix (Figure 2.16). This is further characterised by an approximate ...
DNA and RNA Structure 31 whereas B-DNA has little roll and small positive slide. These and other movements of base pairs are ill ...
with a standard right-handed helix, for which helix twist is 36° and base pair slide is 0.4 Å in B-DNA. However, these extremes ...
concentration stabilises the Z-conformation because it has a much smaller separation between the phos- phate anions in opposing ...
being its 3-neighbour, both in the opposing strand. This network of hydrogen bonds gives added rigidity to the duplex and may e ...
very well with experimental observations on polymorphic forms of DNA. The main conclusions can broadly be summarised as follows: ...
Propeller twist averages –11° for CG pairs and17° for AT pairs. Base pairs ‘roll’ along their long axes to reduce clashing. ...
X-ray analysis of DNA fragments with potential mispairs cannot give any information about the tran- sient occurrence of rare tau ...
pattern of hydration. This arises in part because the two mismatched GA pairs are 2.0 Å wider (from C-1 to C-1) than a conven ...
superhelix with a radius of curvature of 43 Å. To achieve this, the major and minor grooves are compressed on the inside of the ...
Studies on the hydrodynamic properties of DNA show that general-sequence DNA migrates through gels more slowly than expected whi ...
are sensitive to single-strand nucleases, such as S1 and P1, and especially to chemical reagents such as bromoacetaldehyde, osmi ...
This more common pathway is typified by the behaviour of plasmid pIRbke8. Following the formation of a relatively small unpaired ...
molecules.^29 But while ions are often visible in structures of nucleic acids, it is not straightforward to determine how they a ...
its major and minor grooves by cations, consistent with a more or less canonical B-form geometry. By contrast, those who emphasi ...
of alkali metal ions present in the crystallisations. Moreover, MD simulations of A-tract DNA in the pres- ence of different cla ...
and the two bases extruded from the helix on either side. A sharp turn accommodates the reversal in the backbone direction and a ...
superhelical DNA from cells and virions. The energy of supercoilingis a quadratic function of the density of supercoils as descr ...
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