[Microcalorimetric study of heat denaturation of DNA from calf thymus DNA in the absence of magnesium ions].
Thermal denaturation was studied for a wide range of magnesium ions concentrations and salt concentration 0.15 M NaCl. It was shown that thermal stability of DNA increases at low Mg/2P ratios and decreases at high concentrations of magnesium ions. Up to Mg/2P = 10 DNA denaturation is an equilibrium process. With an increase in magnesium ions concentrations the enthalpy of DNA denaturation reaches the maximum at Mg/2P = 10 (50 kJ/mole base pairs). DNA aggregation and appearance of a new heat absorption peak is observed in the high temperature region at Mg/2P = 10. At this region of magnesium ions concentrations DNA denaturation process is non-equilibrium.
Vlasov
A P
AP
Iakhontova
L I
LI
Andrianov
V T
VT
D000818:Animals; D002152:Calorimetry, Differential Scanning; D002413:Cations, Divalent; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D006358:Hot Temperature; D008274:Magnesium / Q000378:metabolism*; D009691:Nucleic Acid Denaturation; D013816:Thermodynamics; D013950:Thymus Gland / Q000737:chemistry
D002413:Cations, Divalent; D004247:DNA; D008274:Magnesium
Mikrokalorimetricheskoe issledovanie teplovoĭ denaturatsii DNK iz timusa telenka v prisutstvii ionov magniia.