Search academic texts

Information × Registration Number 0307U001642, 0106U001548 , R & D reports Title Mechanisms of influence of physical factors and biologically active substances on DNA, proteins and biological membranes popup.stage_title Вплив іонізуючого випромінювання і БАР на ДНК, білки крові і мембранні системи Head Maleev V.,Gatash S., Registration Date 17-04-2007 Organization Kharkov National University named after V.N.Karazin popup.description2 Subject of research: DNA, fibrinogen, biological active substances - actinocin derivative, ethidium bromide and Hoechst 33258 and daunomycin, pyrene, model lipid membranes and host erythrocyte membranes. The purpose of the work is to investigate the binding of actinocine derivative ActII with DNA in the presence of competing ligands, influence of ionizing radiation on fibrinogen and to determine the molecular mechanisms of interactions of model lipid membranes and host erythrocyte membranes with daunomycin and pyrene. Methods: VIS-UV spectrophotometry, HF-dielectrometry, fluorescence spectroscopy. The competitive binding of actinocine derivative ActII with calf thymus DNA in the presence of ethidium bromide (EtBr) and Hoechst 33258 (HT) was studied via spectrophotometrical method in VIS and UV spectra regions. It is shown that in the middle and high P/D regions ActII binds to DNA forming two types of complexes. An analyses of the concentration dependences of ActII - DNA absorption spectra and corresponding binding isotherms in the presence of EtBr and HT allowed to obtain binding constants and binding site sizes values for these types of complexes. It is shown that EtBr and HT compete with ActII for the DNA intercalation and groove binding sites. The influence of g-irradiation on conformation changes of the human fibrinogen in aqueous solution by the microwave dielectric method on the frequency ~9,2 GHz have been studied. The real e' and imaginary e'' parts of the complex dielectric permittivity of the native and irradiated with doses 20, 60 and 100 Gy fibrinogen solutions at the temperature range 2 - 70 °C were measured. The conformation transitions of fibrinogen were found out at 25, 33 and 63 °C. It have been determined that the effect of g-irradiation results in the structure disordering of volume water in solution in the region of melting of the thermolabile domains of fibrinogen the reason which can be removal of aC-domains. It has been received that molecules of daunomycin is distributing in membrane hydrophobe region near molecules of pyrene, as in host erythrocytes well as in liposomes by the method of resonance energy transfer. Results of the research can be used in cancer treatment and radiotherapy procedures at Institute of medical radiology of Ministry of Health of Ukraine. DNA, FIBRINOGEN, ACTINOCIN, ETHIDIUM BROMIDE, HOECHST 33258, DAUNOMYCIN, PYRENE, HOST ERYTHROCYTE MEMBRANES, LIPOSOMES, COMPLEXATION, HYDRATION, g-IRRADIATIONS, HF-DIELECTROMETRY, FLUORESCENT SPECTROSCOPY, VIS-UV SPECTROPHOTOMETRY. Conditions of reception of the report: under the contract. 61077, Kharkov, Svobody sq., 4, V.N. Karazin Kharkov National University Product Description popup.authors popup.nrat_date 2020-04-02 Close