[Translocation of ribonuclease through the membrane of liposomes of various lipid composition]. / Issledovanie translokatsii ribonukleazy cherez membrany liposom razlichnogo lipidnogo sostava.

It was demonstrated that the incorporation of RNAase into liposomes and the activity of the incorporated enzyme depends on the lipid composition of liposomes. The enzyme transfer across membranes was demonstrated, and the quantitative characteristics of this process were obtained. It was found that the rate of transfer and the amount of the transferred enzyme depend on the lipid composition of membranes.

[Characteristics of prostaglandin E1 interaction with components of biological membranes]. / Osobennosti vzaimodeistviia prostaglandina E1 s komponentami biologicheskikh membran.

To estimate the connection between physico-chemical characteristics and biological activity of prostaglandins the interaction of prostaglandin E1 with biological membrane lipids was studied. It is shown that as a result of prostaglandin interaction with phosphatidylcholine a complex is formed that behaves as an individual component and occupies in the surface layer twice as large area than the complex with prostaglandin F2 alpha. The prostaglandin E1 film collapses earlier than F2 alpha. Both facts indicate that the first is more friable. A difference in morphology of prostaglandin monolayers was revealed by electron microscopy. When studying the catalytic activity of peroxidase incorporated in prostaglandin E1 and F2 alpha monolayers some differences were also revealed. In the second case oxidation with methylblue located under the monolayer proceeds more actively. The results obtained point to the connection between the regulatory function of prostaglandins and their chemical structure. Molecular rearrangements of the monolayer caused by prostaglandin incorporation were recorded.

[Study of the physico-chemical properties of prostaglandin F2 alpha and its complexes]. / Izuchenie fiziko-khimicheskikh svoistv prostaglandinaF2 alpha i ego kompleksov.

To study the intracellular action mechanisms of prostaglandin F2 alpha its interaction with lipid components of biological membranes was investigated. It has been found that prostaglandin forms a complex with phosphatidylcholine and cholesterol. Immobilization ability of phospholipids is changed in the course of complex formation. Ability of prostaglandin F2 alpha for complex formation with insulin was also observed. Combination of monolayer technique and electron microscopy made possible to discover molecular reconstructions when prostaglandin is incorporated into monolayer of biologically active compounds.

[Interactions of ribosomes with an unsaturated fatty acid]. / Izuchenie vzaimodeistviia ribosom s nenasyshchenooi zhirnoi kislotoi.

The interaction of bacterial and plant ribosomes with an unsaturated fatty acid and the effect of the latter on the physico-chemical properties of the ribosomes were studied. The ability of E. coli ribosomes and ribosomes from pea seedlings chloroplasts and cytoplasm to form complexes during interaction with the oleic acid were revealed. Evidence for heterogeneity of the bacterial ribosomal fraction, which manifests itself in the fact fat not all ribosomes within a single population are capable to interaction with the oleic acid have been obtained. Changes in the sedimentation and morphological properties typical for different types of ribosomes were observed. The interaction of bacterial ribosomes with the oleic acid and a subsequent removal of the oleic acid with Triton X-100 resulted in an increase of the sedimentation coefficient of the particles from 70S up to 175S and a considerable compactization of ribosomal particles. No such changes were observed in the case of plant ribosomes.

[Permeability of artificial lipid membranes to some enzymes]. / Issledovanie pronitsaemosti model'noi lipidnoi membrany dlia nekotorykh fermentov.

The permeability of artificial lipid membranes for six enzymes, e.g. RNAse, trypsin, amylase, aldolase, invertase and alkaline phosphatase, was studied. The permeability coefficient values for these enzymes were calculated. It was shown that the penetration process consists of several steps: adsorption of enzyme on the membrane surface, diffusion of enzyme molecules through the lipid layer and enzyme desorption into the surrounding solution. The results obtained suggest that the diffusion of the enzyme molecules through the lipid layer is the limiting step of the penetration process.

[Relationship between the surface properties of phosphoglycerides and the structure of the phosphorus part of the molecule]. / O zavisimosti poverkhnostnykh svoistv fosfoglitseridov ot stroeniia fosfornoi chasti molekuly

Comparative studies have been made on surface properties of phospholipids with different chemical composition and different structure of the hydrophylic moiety of the molecule. Substitution of phosphoroyl oxygen by sulfur, as in diacetyl lecithins, makes thiolecithin molecules in monolayer more compact. In case of an analogous substitution of oxygen by sulfur in phosphodiglycerides, packing of molecules in a monolayer remains unaffected. It may be suggested that this fact is associated with different position of hydrophobic radicals in the compounds investigated. In contrast to classic neutral and phosphorus-containing phosphoglycerides, diolphospholipids form more condensed monolayers. It was shown that alpha- and beta-phosphatidic acids with the same composition exhibit identical surface activity. Incorporation of hydrophobic groups of aromatic type into synthetic phospholipid analogues increases surface activity, the effect being dependent on the location of these groups with the molecule.