Abstract
The assembly of double stranded DNA helices with divalent manganese ion is favored by increasing temperature. Direct force measurements, obtained from the osmotic stress technique coupled with x-ray diffraction, show that the force characteristics of spontaneously precipitated Mn(2+)-DNA closely resemble those observed previously by us for other counterion condensed DNA assemblies. At temperatures below the critical one for spontaneous assembly, we have quantitated the changes in entropy and manganese ion binding associated with the transition from repulsive to attractive interactions between helices mediated by osmotic stress. The release of structured water surrounding the DNA helix to the bulk solution is the most probable source of increased entropy after assembly. Increasing the water entropy of the bulk solution by changing the manganese salt anion from CI- to ClO4- predictably and quantitatively increases the transition entropy. This is further evidence for the dominating role of water in the close interaction of polar surfaces.
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Selected References
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- Collins K. D., Washabaugh M. W. The Hofmeister effect and the behaviour of water at interfaces. Q Rev Biophys. 1985 Nov;18(4):323–422. doi: 10.1017/s0033583500005369. [DOI] [PubMed] [Google Scholar]
- Eichhorn G. L., Shin Y. A. Interaction of metal ions with polynucleotides and related compounds. XII. The relative effect of various metal ions on DNA helicity. J Am Chem Soc. 1968 Dec 18;90(26):7323–7328. doi: 10.1021/ja01028a024. [DOI] [PubMed] [Google Scholar]
- Granot J., Assa-Munt N., Kearns D. R. Interactions of DNA with divalent metal ions. IV. Competitive studies of Mn2+ binding to AT- and GC-rich DNAs. Biopolymers. 1982 May;21(5):873–883. doi: 10.1002/bip.360210502. [DOI] [PubMed] [Google Scholar]
- Granot J., Feigon J., Kearns D. R. Interactions of DNA with divalent metal ions. I. 31P-NMR studies. Biopolymers. 1982 Jan;21(1):181–201. doi: 10.1002/bip.360210115. [DOI] [PubMed] [Google Scholar]
- Leikin S, Rau DC, Parsegian VA. Measured entropy and enthalpy of hydration as a function of distance between DNA double helices. Phys Rev A. 1991 Oct 15;44(8):5272–5278. doi: 10.1103/physreva.44.5272. [DOI] [PubMed] [Google Scholar]
- McGhee J. D., Wood W. I., Dolan M., Engel J. D., Felsenfeld G. A 200 base pair region at the 5' end of the chicken adult beta-globin gene is accessible to nuclease digestion. Cell. 1981 Nov;27(1 Pt 2):45–55. doi: 10.1016/0092-8674(81)90359-7. [DOI] [PubMed] [Google Scholar]
- Michel B. E. Evaluation of the water potentials of solutions of polyethylene glycol 8000 both in the absence and presence of other solutes. Plant Physiol. 1983 May;72(1):66–70. doi: 10.1104/pp.72.1.66. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parsegian V. A., Rand R. P., Fuller N. L., Rau D. C. Osmotic stress for the direct measurement of intermolecular forces. Methods Enzymol. 1986;127:400–416. doi: 10.1016/0076-6879(86)27032-9. [DOI] [PubMed] [Google Scholar]
- Prouty M. S., Schechter A. N., Parsegian V. A. Chemical potential measurements of deoxyhemoglobin S polymerization. Determination of the phase diagram of an assembling protein. J Mol Biol. 1985 Aug 5;184(3):517–528. doi: 10.1016/0022-2836(85)90298-0. [DOI] [PubMed] [Google Scholar]
- Rand R. P. Interacting phospholipid bilayers: measured forces and induced structural changes. Annu Rev Biophys Bioeng. 1981;10:277–314. doi: 10.1146/annurev.bb.10.060181.001425. [DOI] [PubMed] [Google Scholar]
- Rau D. C., Lee B., Parsegian V. A. Measurement of the repulsive force between polyelectrolyte molecules in ionic solution: hydration forces between parallel DNA double helices. Proc Natl Acad Sci U S A. 1984 May;81(9):2621–2625. doi: 10.1073/pnas.81.9.2621. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rau D. C., Parsegian V. A. Direct measurement of forces between linear polysaccharides xanthan and schizophyllan. Science. 1990 Sep 14;249(4974):1278–1281. doi: 10.1126/science.2144663. [DOI] [PubMed] [Google Scholar]
- Rau D. C., Parsegian V. A. Direct measurement of the intermolecular forces between counterion-condensed DNA double helices. Evidence for long range attractive hydration forces. Biophys J. 1992 Jan;61(1):246–259. doi: 10.1016/S0006-3495(92)81831-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zimmerberg J., Parsegian V. A. Polymer inaccessible volume changes during opening and closing of a voltage-dependent ionic channel. Nature. 1986 Sep 4;323(6083):36–39. doi: 10.1038/323036a0. [DOI] [PubMed] [Google Scholar]
