[Energetics of hydration of nucleic acids with various nucleotide composition]. / Energetika gidratatsii nukleinovykh kislot razlichnogo nukleotidnogo sostava.

The energetics of hydration of natural DNA of different AT/GC content and model double-helical polyribonucleotides was studied. The results obtained by a new approach, which is based on calorimetric measurements of hydration-dehydration energy of nucleic acid-water systems at different relative humidities are presented. A correlation between the dehydration energy and the nucleotide composition of native DNA was found. The energetic characteristics of systems containing deoxynucleoside monophosphates and water clusters of different dimensions were obtained by the Monte Carlo method. The results of computer simulation correlate with the experimental calorimetric data.

[Dynamic properties of water bound to matrices of natural DNA and model complexes]. / Dinamicheskie svoistva vody, sviazannoi na matritsakh prirodnykh DNK i model'nykh kompleksov.

From experimental data on the hydration energetics of nucleic acids obtained by differential scanning calorimetry under isothermal conditions, dielectric relaxation time tau d and "free volume" Vf occupied by water molecules in hydration shells of natural DNA and model polyribonucleotides were calculated. In addition, systems consisting of dinucleotides ApA, TpT, UpU, TpU, UpT and water clusters of various sizes (from 20 to 400 water molecules) were studied by Monte Carlo computer simulation. It was shown that, as water content in systems increases, the dynamic characteristics of bound water obtained with both methods approached the values for bulk water.

[Energetics of hydratation of nucleic acids with various nucleotide composition]. / Energetika gidratatsii nukleinovykh kislot razlichnogo nukleotidnogo sostava.

The hydration energetics of natural DNA with various AT/GC-composition and model double-helix polyribonucleotides was studied using a new approach which is based on calorimetric measurements of the dehydration energy of nucleic acid-water systems at various levels of relative humidity. A linear correlation between the dehydration energy and the nucleotide composition of natural DNA was found.

[Thermogravimetric analysis of the aqueous dispersion of egg lecithin and Na-DNA]. / Termogravimetricheskii analiz vodnykh dispersii iaichnogo letsitina i Na-DNK.

Thermogravimetric studies of egg yolk lecithin water dispersion were carried out under conditions similar to those previously used in DSC studies of model biomembranes. For comparison, water dispersion of Na-DNA from calf thymus was studied in a parallel series. In both cases several distinct states of associated water were observed. The biomolecule/water stoichiometry obtained is compared with respective literature data.