An approximate approach to DNA denaturation.
A quantum-statistical-mechanical theory of equilibrium states was developed to present a simple realistic model of DNA denaturation. Applying the Feynman free energy minimum principle approach to the free energy of an anharmonic oscillator representing an interchain H-bond between DNA strands a simple formula for its melting temperature was derived. Experimental Raman and IR vibrational data were used, and if not available the vibrational data for individual H-bonds in guanine-cytosine and adenine-thymine base pairs were assigned using the Prohofsky self-consistent phonon approach; moreover, the Morse potential parameters were taken over from the same source. On the basis of them the H-bond force constants and then H-bond melting temperatures were calculated for individual H-bonds in the base pairs. The calculated average melting temperatures were compared with the experimental ones for various samples of DNA. Very reasonable results were obtained.
Valko
L
L
Department of Physical Chemistry, Faculty of Chemical Technology, Slovak Technical University, Bratislava, Slovakia.
Gersi
P
P
D000225:Adenine; D001482:Base Composition; D003596:Cytosine; D004247:DNA / Q000737:chemistry*; D004269:DNA, Bacterial / Q000737:chemistry*; D006147:Guanine; D006860:Hydrogen Bonding; D008956:Models, Chemical; D008961:Models, Structural; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D011089:Polydeoxyribonucleotides / Q000737:chemistry; D013816:Thermodynamics; D013941:Thymine; D013997:Time Factors
D004269:DNA, Bacterial; D011089:Polydeoxyribonucleotides; D006147:Guanine; D003596:Cytosine; D004247:DNA; D000225:Adenine; D013941:Thymine