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Iu G Sharimanov

Publications and source records attributed to Iu G Sharimanov.

9 recordsLinked to original sources
PubMedDate not supplied

[Study of dynamic properties of water in poly(A) and poly(U) solutions by proton magnetic resonance].

Proton magnetic relaxation in aqueous solutions of polyadenylic and polyuridylic acids in the temperature range (10-80 degrees C) and acidities (pH 3-9.7) has been investigated. Activation energies of water molecule diffusion and proton exchange, as well as the velocities of these processes have been determined. It is established that from the point of view of magnetic relaxation, the state of single helices resulted from the thermal conformation transition, are not equal to the state obtained by the change of the pH of solution; it refers both to the secondary structure of the chains and the dynamical behaviour of the biopolymer hydrate layers.

Chemical Phenomena↗
PubMedDate not supplied

[Proton magnetic relaxation and thermodynamic parameters of ribonuclease solutions during thermal denaturation].

Heat denaturation of ribonuclease in diluted water solutions was studied by means of proton magnetic relaxation, microcalorimetry and viscosity. It has been shown that heat denaturation of ribonuclease is a one stage process; it involves the whole globule and is accompanied by changes in the state of salvated (water) molecules. A redistribution of water molecules in the hydrate "envelope" of protein changes the character of proton magnetic relaxation of the whole solvent.

Hot Temperature↗
PubMedDate not supplied

[Ftorafur interaction with biopolymers].

High resolution NMR spectra were studied on 1H, 13C and 19F nuclei of antitumor drug ftorafur . The lines in NMR spectrum of 1H and 19F representing individual fragments of ftorafur molecule were shown to be broadened in the presence of BSA and DNA. These broadenings reflect the formation mechanisms of ftorafur complexes with indicated biopolymers during transport and antitumor effect of the drug.

Animals↗
PubMedDate not supplied

[Study of the aqueous phase transition in a collagen--water system by the calorimetric and NMR methods].

Heat capacity and line width of proton magnetic resonance of collagen were studied by means of low-temperature calorimatry and high resolution NMR spectroscopy at different values of moisture in the temperature range of ice-water phase transition. Peculiarities of water phase transition in the presence of biopolymers were revealed. It was shown that a definite part of H2O in the "hydration layers" of the macromolecules (0.35 g of H2O/g of protein) is not transformed into ice even at a temperature decrease up to 4 K. The NMR data show that the total mobility of the bound water molecules remains high enough up to the water concentration at which the inner hydration layer of the macromolecule is formed. After the formation of hydrogen-bound water chains in the hydrate layers of collagen the mobility of the bound water molecules decreases.

Calorimetry↗