Summary
An obvious difficulty of the Watson-Crick model of DNA is that the intertwining of the strands would seem to hinder their separation during replication. The nature of the difficulty is here made precise and is called the alignment problem. It is shown that the swivelase theory, found in current textbooks and thought to overcome the difficulty, does not in fact do so. The various conceivable solutions of the alignment problem are considered and rejected, leading to the conclusion that chromosomal DNA is not double-helical. An alternative model of DNA is discussed. In addition a topological classification of DNA denaturation processes is given, and an alternative interpretation of the gel electrophoresis experiments on circular duplex DNA is suggested.
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References
Alberts, B., Sternglanz, R.: Recent excitement in the DNA replication problem. Nature269, 655–661 (1977)
Bauer, W., Vinograd, J.: The interaction of closed circular DNA with intercalative dyes. I. The superhelix density of SV40 DNA in the presence and absence of dye. J. Mol. Biol.33, 141–171 (1968)
Cairns, J.: The bacterial chromosome. Scientific American, Jan. 1966
Crick, F. H. C.: Linking numbers and nucleosomes. Proc. Natl. Acad. Sci. USA73, 2639–2643 (1976)
Depew, R. E., Wang, J. C.: Conformal flucturations of DNA helix. Proc. Natl. Acad. Sci. USA72, 4275–4279 (1975)
Frank-Kamenetskii, M. D., Lukashin, A. V., Vologodski, A. V.: Statistical mechanics and topology of polymer chains. Nature258, 398–402 (1975)
Freifelder, D.: Physical Biochemistry. San Francisco: Freeman, 1976
Fuller, F. B.: The writhing number of a space curve. Proc. Natl. Acad. Sci. USA68, 815–819 (1971)
Germond, J. E., Hirt, B., Oudet, P., Gross-Bellard, M., Chambon, P.: Folding of the DNA double helix in chromatin-like structures from Simian Virus 40. Proc. Natl. Acad. Sci. USA72, 1843–1847 (1975)
Hayes, W.: The Genetics of Bacteria and their Viruses. Oxford and Edinburgh: Blackwell, 1968
Keller, W.: Determination of the number of superhelical turns in simian virus 40 DNA by gel electrophoresis. Proc. Natl. Acad. Sci. USA72, 4876–4880 (1975)
Kornberg, A.: DNA Synthesis. San Francisco: Freeman, 1974
Lehninger, A. L.: Biochemistry (2nd edition). New York: Worth, 1975
Liu, L. F., Depew, R. E., Wang, J. C.: Knotted single-stranded DNA rings: A novel topological isomer of circular single-stranded DNA formed by treatment withEscherichia coli ω protein. J. Mol. Biol.106, 439–452 (1976)
Liu, L. F., Wang, J. C.: On the degree of unwinding of the DNA helix by ethidium II. Studies by electron microscopy. Biochim. et Biophys. Acta395, 405–412 (1975)
Parker, D. L., Glaser, D. A.: Effect of growth conditions on DNA-membrane attachment inEscherichia coli. Proc. Natl. Acad. Sci. USA72, 2446–2450 (1975)
Pohl, W. F.: The self-linking number of a closed space curve. Journal of Mathematics and Mechanics17, 975–986 (1968)
Pulleyblank, D. E., Shure, M., Tang, D., Vinograd, J., Vosberg, H.-P.: Action of nicking-closing enzyme on supercoiled and nonsupercoiled closed circular DNA: Formation of a Boltzmann distribution of topological isomers. Proc. Natl. Acad. Sci. USA72, 4280–4284 (1975)
Rodley, G. A., Scobie, R. S., Bates, R. H. T., Lewitt, R. M.: A possible conformation for double-stranded polynucleotides. Proc. Natl. Acad. Sci. USA73, 2959–2963 (1976)
Wang, J. C.: Variation of the average rotation angle of the DNA helix and the superhelical turns of covalently closed cyclic λ DNA. J. Mol. Biol.43, 25–39 (1969)
Wang, J. C.: Degree of superhelicity of covalently closed cyclic DNA's fromEscherichia coli. J. Mol. Biol.43, 263–272 (1969)
Wang, J. C.: Interaction between DNA and anEscherichia coli protein ω. J. Mol. Biol.55, 523–533 (1971)
Wang, J. C.: The degree of unwinding of the DNA helix by ethidium I. Titration of twisted PM2 DNA molecules in alkaline cesium chloride density gradients. J. Mol. Biol.89, 783–801 (1974)
Wang, J. C., Liu, L.: DNA topoisomerases: enzymes which catalyse the concerted breaking and rejoining of DNA backbone bonds. (To appear)
Watson, J. D.: Molecular Biology of the Gene (3rd edition). Menlo Park, Calif.: Benjamin, 1976
White, J. H.: Self-linking and the Gauss integral in higher dimensions. American Journal of Mathematics91, 693–728 (1969)
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Pohl, W.F., Roberts, G.W. Topological consideration in the theory of replication of DNA. J. Math. Biology 6, 383–402 (1978). https://doi.org/10.1007/BF02463003
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DOI: https://doi.org/10.1007/BF02463003