[Effect of the external electrostatic field on the conformation of a macromolecule containing charged groups]. / Vliianie vneshnego élektrostaticheskogo polia na konformatsiiu makromolekuly, soderzhashchei zariazhennye gruppy.

A method for calculating the free energy of a macromolecule containing charged groups in electrostatic field in aqueous solution was proposed. The non-electrostatic component of free energy was calculated with consideration of van der Waals interactions between uncharged parts of the macromolecule. The electrostatic component of free energy was calculated with regard for the interactions of charged groups of the macromolecule with each other and with water molecules. It was found that, depending on the strength of external electric field, the free energy of the system passes through a minimum, whereas the internal energy passes through a maximum. By minimizing the free energy, relative changes in the mean radius 'r' and the distance between the termini of the macromolecule 'h' were calculated. It was found that, at some values of field strength, both 'r' and 'h' decrease. An increase in strength led to an increase in 'r' and 'h'. The regularities observed depend on the charge of the macromolecule and the spatial redistribution of macromolecules and counterions.

[Prostaglandin D2-synthase from cattle brain: purification and physico-chemical properties]. / Prostaglandin D2-sintaza iz mozga byka: ochistka i fiziko-khimicheskie svoistva.

Prostaglandin D2-synthase has been purified from bovine brain for the first time and characterized. The enzyme has a molecular mass of 21 kDa and a pH optimum at 9.0 and is activated by dithiothreitol. The presence in the enzyme molecule of carbohydrates and lipids has been established and a preliminary conclusion made about the qualitative composition of the lipids. The ability of the enzyme to form aggregates under the influence of the detergent has been demonstrated. The role of the lipid component in the preservation of the enzyme monomeric structure as well as the possible mechanisms of action of the above inhibitors and activators are discussed.

[Erythrocyte elastic and mechanical properties and mechanism of their change during irradiation]. / Issledovanie uprugomekhanicheskikh svoistv éritrotsitov i mekhanizmov ikh izmenenii pri obluchenii.

A decrease in erythrocyte deformation, which was maximum at the height of radiation sickness, was registered as early as 1-3 days following 6 Gy irradiation of rats. The aggregation of erythrocytes increased during the latent period of radiation sickness then sharply decreased. The role of the observed changes in radiation sickness then pathogenesis is discussed. It is established that they are associated with the altered fatty acid composition of the lipid phase of erythrocytic membranes, on the one hand, and with the disturbances in its ionic permeability, on the other.