Determination of the base composition of deoxyribonucleic acid from its thermal denaturation temperature*

https://doi.org/10.1016/S0022-2836(62)80066-7Get rights and content

The previously discovered linear relation between the base composition of DNA, expressed in terms of percentage of guanine plus cytosine bases, and the denaturation temperature, Tm, has been further investigated. By means of measurements on 41 samples of known base composition the previously observed relation has been confirmed. It can be summarized thus : for a solvent containing 0·2 M-Na+, Tm = 69·3 + 0·41 (G-C) where Tm is in degrees Centigrade and G-C refers to the mole percentage of guanine plus cytosine. The deviations of experimental points from this relation are no more than that expected from the uncertainties of base analysis and the variations of a half degree in the reproducibility of determining the Tm. Consequently it appears that the measurement of the Tm is a satisfactory means of determining base composition in DNA. The Tm values are most simply measured by following the absorbance at 260 mμ as a function of temperature of the DNA solution and noting the midpoint of the hyperchromic rise. Only 10 to 50 μg of DNA are required.

A number of other DNA samples of unknown base composition have been examined in this manner and their base compositions recorded.

References (18)

  • A.N. Belozersky et al.
  • K.S. Kirby

    Biochim. biophys. Acta

    (1959)
  • H.R. Mahler et al.

    Biochem. Biophys. Res. Comm.

    (1961)
  • J. Marmur

    Biochim. biophys. Acta

    (1960)
  • J. Marmur

    J. Mol. Biol.

    (1961)
  • C.L. Schildkraut et al.

    J. Mol. Biol.

    (1962)
  • R.L. Sinsheimer
  • B.W. Catlin et al.

    J. Gen. Microbiol.

    (1961)
  • E. Chargaff
There are more references available in the full text version of this article.

Cited by (3037)

  • Quantification of mirtazapine in tablets via DNA binding mechanism; development of a new HPLC method

    2024, Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences
View all citing articles on Scopus
*

This work was supported by grants from the United States Public Health Service (C-2170) and the National Science Foundation (G-13990). Part of the work was carried out at Brandeis University.

Present address: Graduate Department of Biochemistry, Brandeis University, Waltham, Massachusetts.

View full text