Volume 5, Number 3/4, pp. 100-102
Microcalorimetric study of the helix-coil transition of calf thymus DNA at very low concentrations of the peptide bioregulator vilon
D. Khachidze 1, Sh. Barbakadze 1, M. Gorgoshidze 1, G. Majagaladze 1, M. Kiladze 1, J. Monaselidze 1 and T. Lezhava 2
1
E. Andronikashvili Institute of Physics, Georgian Academy of Sciences, 6, Tamarashvili Street, Tbilisi, Georgia
2
I. Javakhishvili Tbilisi State University of Georgia, 3, University Street, Tbilisi, Georgia
The thermodynamic parameters (ΔHmelt, Tmelt) of the helix-coil transition of calf thymus DNA in the presence of very low concentrations of the bioregulator peptide vilon have been determined. It was shown that the 7.5 °C increase in the calf thymus DNA melting temperature (Tmelt) without any significant change of melting enthalpy was observed in the range 7 × 10-5 to 5.2 × 10-3 moles vilon per mole DNA base pairs. It is proposed that the increase of Tmelt is connected with the decrease of the transition entropy (ΔSmelt) due to the formation of specific intramolecular crosslinking sequences.
Keywords: bioregulator, melting, melting enthalpy, melting entropy, microcalorimetry, vilon