[Dimeric mechanism of the work of nigericin in bilayer lipid membranes]. / Dimernyi mekhanizm raboty nigeritsina na bisloinykh lipidnykh membranakh

The electric properties of the bilayer lethitin membranes have been studied in the presense of the antibiotic nigericin. When the antibiotic concentration is about 10(-6) M the condactivity of the BLM is increased upto 10(-7) ohm-1cm-2. The potassium ion concentration gradient gives rise to a transmembrane potential of the order of 40 mV per 10--fold concentration gradient with the side of the higher potassium concentration negative. The transmembrane potential produced by the hydrogen ion gradient is a function of the potassium ion concentration which is equal on both sides of the membrane. In order to account for the experimental results obtained, a theoretical approach has been developed based on the assumption that charge is transported across the membrane by nigericin dimers.

[Electron transfer through the octane/water interface in the presence of chlorophyll]. / Perenos élektronov cherez granitsu razdela oktan/voda v prisutstvii khlorofilla

The data obtained by the vibrating electrode method in the investigation of the system octane/water containing chlorophyll adsorbed on the interface and redox systems in both phases show that chlorophyll is capable in the absence of illumination to transfer electrons from one redox reaction to another one, injecting charges from water into octane. It was shown that charge transfer reaction accompanied by proton injection in the unstirred interfacial layer.

[Electrogenic function of submitochondrial particles at the water-octane interphases]. / Elektrogennaia funktsiia submitokhondrial'nykh chastits na granitse razdela faz oktan/voda.

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.

[Proton transfer from water to octane coupled with the reaction of ATP hydrolysis by soluble ATPase from chloroplasts]. / Perenos protonov iz vody v oktan, sopriazhennyi reaktsiei gidroliza ATF rastvorimoi ATFazoi khloroplastov

It has been shown that soluble ATPase from chloroplasts adsorbed at the octane/water interface generates an ATP hydrolysis coupled potential charge (deltapi) at the interphase. This process occurs in the presence of a lipid-soluble proton acceptor, in the capacity of which 2,4-dinitrophenol is used. The dependence of deltapi, generated by ATPase, on the concentration of the enzyme. ATP and dinitrophenol, has been studied.

[Lipid oxidation in bilayer lipid membranes linked with the reaction of oxidation of NAD.H by atmospheric oxygen]. / Okislenie lipidov bisloinykh lipidnykh membran, sopriazhennoe s reaktsiei okisleniia NAD.H kislorodom vozdukha

It is shown that along with NAD.H oxidation with air oxygen peroxide oxidation of lipids forming the membrane takes place in bilayer lipid membranes modified with ubiquinone. During nicotin amide oxidation proton absorption takes place. Peroxide oxidation of lipids results in the liberation of H+ ions, which in its turn brings about the formation of protone-deficient or enriched (against aqueous solution) layers adjacent to the membrane. The potential value on the membrane is shown to depend on nicotine amide and oxygen concentration, on ubiquinone presence and lipid composition of the membrane. It has been also indicated that the transmembrane potential difference is initiated with a sharp change of aqueous solution pH by 0.05--0.4 units.

[Structure of the double electric layer at membrane/aqueous solution interfaces in the presence of tetrapentylammonium cations]. / Stroenie dvoinogo élektricheskogo sloia na granitse razdele membrana/vodnyi rastvor v prisutstvii kationov tetrapentilammoniia

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.

[Mechanism of action of the specific inhibitor of respiration and phosphorylation in mitochondria--n-(N,N-di-2-chlorethyl)aminophenylacetic acid]. / Issledovanie mekhanizma deistviia spetsificheskogo ingibitora dykhaniia i fosforilirovaniia v mitokhondriiakh--n-(N,N-di-2-khlorétil)aminofeniluksusnoi kislety

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.

[Properties of bilayer lipid membranes with different surface charges in the presence of tetraalkylammonium salts]. / Izuchenie svoistv bisloinoi lipidnoi membrany s raznymi poverkhnostnymi zariadami v prisutstvii tetraalkilammonievykh solei

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-.