Determination of the base composition of deoxyribonucleic acid from its buoyant density in CsCl

doi:10.1016/S0022-2836(62)80100-4

Journal of Molecular Biology

Volume 4, Issue 6, June 1962, Pages 430-443

https://doi.org/10.1016/S0022-2836(62)80100-4 Get rights and content

A comprehensive study of the buoyant density of DNA as a function of composition has been made. The linear relation previously reported has been confirmed. Based on a value of 1·710 g cm⁻³ for DNA from Escherichia coli the following relation was obtained from the best fit of measurements on 51 different DNA samples: $ρ = 1 \cdot 660 + 0 \cdot 098 (G C)$ where ρ refers to buoyant density and (GC) to the mole fraction of guanine plus cytosine. On this basis the composition of DNA from 36 other sources, not previously reported, has been estimated. Several specific observations were made. Bimodal distributions in the density-gradient band patterns were found in DNA from calf thymus and salmon sperm. The DNA of the commonly studied T-even bacteriophages exhibits altered densities due to the presence of gluco-sylated hydroxymethylcytosine. The DNA of φX174 phage is abnormally heavier suggesting less base-pairing than normal denatured, single-stranded DNA.

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^†: Present address: Department of Biochemistry, Stanford University Medical Center, Palo Alto, California.

^‡: Present address: Graduate Department of Biochemistry, Brandeis University, Waltham, Mass.

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Journal of Molecular Biology

Determination of the base composition of deoxyribonucleic acid from its buoyant density in CsCl

Virology

J. Mol. Biol.

Biochim. biophys. Acta

Advanc. Virus Res.

J. Mol. Biol.

J. Mol. Biol.

Arch. Biochem. Biophys.

J. Biol. Chem.

J. Mol. Biol.

J. Mol. Biol.

J. Mol. Biol.

Virology

Proc. Nat. Acad. Sci., Wash.

Biokhimiya