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L I Boguslavskiĭ

Publications and source records attributed to L I Boguslavskiĭ.

At least 19 recordsLinked to original sources

[Mechanism of action of the specific inhibitor of respiration and phosphorylation in mitochondria--n-(N,N-di-2-chlorethyl)aminophenylacetic acid].

An electrophilous inhibitor, p-(N,N-di-2-chloroethyl)amino-phenylacetic acid (I), specifically disturbs the mechanism of respiration and phosphorylation coupling in mitochondria. I inhibits respiration and ATPase activity in intact mitochondria and does not affect these processes in mitochondria and submitochondrial particles with partially or completely impaired coupling system. The data obtained show that I inhibits protonophoric function of NADH-ferricianide reductase from submitochondrial particles soluble ATPases from bovine heart and Micrococcus lysodeikticus mitochondria adsorded on octane water interface and has no effect on respective enzymes in water solutions. Cation-transferring enzymes are shown to behave with respect to the inhibitor on lipid water interface like respective enzymes in intact mitochondria, while in water solutions they behave like those in systems with the impaired coupling mechanism. Effect of I on protonophoric function of oligomycin-sensitive ATPase and bacteriorhodopsin plaques isolated from Halobacterium halobium is also studied. It is shown that the precence or the absence of I effect is due to a nature of lipid in the enzymatic complex. I is found also to inhibit specifically the transport of Ca2+ from water to octane in the presence of Ca2+-ATP-ase from rabbit sarcoplasmic reticulum.

Adenosine Triphosphatases↗

[Electrogenic function of submitochondrial particles at the water-octane interphases].

Studies on submitochondrial particles (SMP) preparation showed that in the sourse of the redox reactions at the octane-water interface, catalyzed by SMP enzymes, the charges are transferred from the aqueous to the octane phase. The effects were detected by a shift of the Volta potential, using the vibrating electrode method. In the presence of 2-N-methyl-amino-1,4-naphthoquinone in octane, acting as electron acceptor, the negative charges were transferred from water to octane following the oxidation of NADH, succinate and ascorbate. The charging of the octane phase was sensitive to the inhibitors of the respiratory chain, e. g. rotenone, antimycin and cyanide. In the presence of 2,4-DNP in octane, acting as a proton acceptor, the oxidation of NADH and succinate by ferricyanide, catalyzed by CMP in the presence of antimycin and cyanide correspondingly, was followed by a transfer of positive charges from water to octane. The positive charging of the octane phase, coupled with NADH oxidation, was found insensitive to rotenone, and that coupled with succinate oxidation, was completely inhibited by antimycin. The positive charging of the octane phase was also observed during the reverse transhydrogenase reaction, catalyzed by SMP at the division of the phases. The effect was inhibited by palmitoyl-CoA.

Alkanes↗

[Properties of bilayer lipid membranes with different surface charges in the presence of tetraalkylammonium salts].

It is shown that with the growth of the radius of tetraalkylammonium ions the conductivity of the membrane increases. With an increase of the dimensions of penetrating ions the maximum cation selectivity reached in the beginning decreases with a further growth of cation radius. A negative charge on the membrane surface results in a higher cation selectivity and conductance mechanism is observed at the transition to the cations with a large radius at their high enough concentration in the aqueous solution. It can be explaind by the formation of triplet in the membrane phase which aid in the penetration of C1-.

Electric Conductivity↗

[Structure of the double electric layer at membrane/aqueous solution interfaces in the presence of tetrapentylammonium cations].

Data are presented on the conductivity of bilayer lipid membranes of phosphatidilethanole amine with different surface charges in the presence of tetrapentylammonium chloride. It follows from the analysis of experimental data that to describe the effect of surface charge on membrane conductivity it is necessary to use a complicated model of double electric layer. Only in some cases Gouy-Chapman theory well describes the experimental results.

Alkanes↗