Counterion effects on the physical properties and the A to B transition of calf‐thymus DNA films
- 1 January 1990
- journal article
- Published by Wiley in Biopolymers
- Vol. 30 (9-10), 877-887
- https://doi.org/10.1002/bip.360300903
Abstract
We report measurements of the water content and swelling of wet‐spun films of Na‐, K‐, Rb‐, and Cs‐DNA as a function of relative humidity (rh). The water contents (number of water molecules per base pair of DNA) of these films are found to be quite similar, indicating that the identity of the counterion species is unimportant for the water content. Since the A to B transition for these DNAs occurs at different rhs, the corresponding water contents of the A to B transition are found to be quite different. These films swell as a function of rh in a very similar manner, implying that the changes in the intermolecular bonds in the different DNAs are similar. Dramatic changes are observed in the dimensions of the films above 84% rh for all types of DNA. Combining the water content and swelling measurements yields the dependence of the volume per base pair on water content. The volume per base pair is observed to be a nonlinear function of water content, indicating nonideal mixing of the water with the DNA.Keywords
This publication has 43 references indexed in Scilit:
- Counterion Effects on the Structure and Dynamics of Solid DNAPhysical Review Letters, 1988
- The origin of the A to B transition in DNA fibers and filmsBiopolymers, 1988
- Statistical mechanics of the B----Z transition of DNA: contribution of diffuse ionic interactions.Proceedings of the National Academy of Sciences, 1984
- DNA StructurePublished by Springer Nature ,1984
- Base Sequence, Helix Structure and Intrinsic Information Readout in DNAPublished by Springer Nature ,1983
- Homocopolymer sequences in the spacer of a sea urchin histone gene repeat are sensitive to S1 nucleaseNature, 1982
- Molecular structure of a left-handed double helical DNA fragment at atomic resolutionNature, 1979
- On the B to A conformation change of the double helixBiopolymers, 1977
- Effect of crosslinking on the secondary structure of DNA. I. Crosslinking by photodimerizationBiochemistry, 1976
- The structure of sodium thymonucleate fibres. I. The influence of water contentActa Crystallographica, 1953