- The principal possibility of determining the sequence of nucleotides in a nucleic acid from the analysis of the related torsional vibrations of nitrogenous bases was shown. The spectra of crystalline bases and nucleosides in the far infrared region were obtained and interpreted. For the first time the phenomenon of DNA hypochromism at the vibrational levels at the absorption band of double and multiple bonds of nitrogenous bases was observed.
- The thermodynamic and structural parameters of biopolymers were studied under their thermal denaturation. Using adiabatic calorimetry and infrared spectroscopy, it was showed that the process of thermal denaturation of globular proteins under normal physiological conditions is not just a globule-coil transition. This process is accompanied by the destruction of the hydration shell of the protein and formation of intra- and intermolecular contacts. The latter leads to irreversible structural transition and reduces total energy effect. In contrast to the proteins, the interaction between the DNA molecules in the concentrated solutions was found to have the entropic nature.
- A large series of studies to determine the structure and stability of the hydration environment of proteins and nucleic acids using specially designed experimental physical methods (dielectrometry in mm range, infrared spectroscopy of wet films, piezogravimetry and differential scanning microcalorimetry of biopolymer-water systems) has been carried out. It has been shown that the conformational transitions in proteins and nucleic acids are accompanied by significant changes in the hydration environment of the biopolymers. Interaction with water was found to cause the main energy effect in the conformational transitions. These results allowed us to conclude that water plays crucial role in the stabilization of the structure of DNA.
- In addition to experimental studies, the theoretical analysis of hydration of biologically active substances and nucleic acids was carried out with help of computer modeling using Monte Carlo and molecular dynamics methods. The non-linear models of hydration АВ transitions in DNA, occurring under changing water content in samples, were suggested.
- The structural and energetic features of the interaction of DNA with biologically active substances (mutagens, drugs) including the newly synthesized antibiotics such as actinocin were studied. The most probable mechanisms of this complex formation that take into account the influence of the water environment were formulated. The conditions of substantial changes in the thermal stability of DNA in the presence of bioactive agents was determined.
- Based on the results of the study of the dielectric properties of proteins, nucleic acids and their components in mm and cm wavelengths, which was carried out using the original differential dielectrometer, the molecular mechanisms of interaction of biomolecules with electromagnetic radiation of these ranges were proposed.
- Using spectroscopic methods, EHF dielectrometry and gel electrophoresis, changes in DNA structure and its hydration surroundings due to ionizing radiation were detected in model experiments with gamma irradiation of DNA-water system, and in experiments with DNA isolated from laboratory animals which were under exposure to radiation in zone of Chernobyl Nuclear Power Station.
- Study of the hydration of collagen, its mineralization processes and complex formation of the mineralized collagen with titanium was carried out to determine the optimal conditions for the formation of such systems when used in clinical practice.
07.04.2015