[Use of bacterial luciferase for determining monoamine oxidase activity]. / Ispol'zovanie bakterial'noi liutsiferazy dlia opredeleniia monoaminooksidaznoi aktivnosti.

A bioluminescence assay is proposed for measuring monoamine oxidase activity in different biological specimens (platelets, mitochondria). The assay is based on the bioluminescent reaction catalysed by bacterial luciferase and coupled to monoamine oxidase. Two modifications of the bioluminescence assay were used. In the first case, the bioluminescent system was added to monoamine oxidase preincubated with the substrates, while in the second case, all the components of the coupled enzymatic systems were directly mixed in a cell. The proposed bioluminescence assay is simple, highly sensitive and rapid, and could be especially useful for biomedical examinations.

[Inhibitory analysis of the luminescent electron transport chain of Photobacterium fischeri]. / Ingibitornyi analiz liuminestsentnoí elektrontransportnoi tsepi Photobacterium fischeri.

The quenching of luminescence of bacterial luciferase from Photobacterium fischeri by non-specific electron acceptors and inhibitors of dehydrogenases was studied. The inhibition of the luminescent reaction obeys the non-competitive mechanism with NADH, FMN and aliphatic aldehyde. The inhibitors compete with cytochrome c for NADH -- cytochrome c oxido-reductase. It is concluded that lumiredoxin, a FeS-containing protein, is the most sensitive component of the luminescent electron transport chain.

[Isolation and purification of bacterial luciferase from Photobacterium fischeri for analytical purposes]. / Vydelenie i ochistka bakterial'noi liutsiferazy iz Photobacterium fischeridlia analiticheskih tselei.

A procedure resulting in a highly purified preparation of bacterial luciferase with a high specific activity towards FMNH2 and NADH was developed. Using SDS-electrophoresis in polyacrylamide gel, it was shown that the enzyme has a subunit composition and that its monomers do not contain the luciferase activity. The use of the obtained preparation for determining the content of NADH and FMN by the bioluminescent method allowed to increase its sensitivity up to 10(-18) and 10(-17) moles, respectively.

[Free radical oxidation of biological membrane lipids. VII. Effect of ultraviolet radiation on free radical oxidation of lipids complexed with protein and in biomembranes]. / Svobodnoradikal'noe okislenie lipidov biologicheskikh membran. VII. Deistvie ul'trafioletovogo izlucheniia na svobodnoradilak'noe okislenie lipidov v komplekse s belkom i v biomembranakh

Promoting effect of protein component on the development of free radical oxidation in the systems ethylarahidonate--bovine serum albumin and mitochondria suspension under UV irradiation has been shown. Connection between the processes of peroxide formation and the change of the functional activity of organells has been followed.

[Fluorescence analysis study of the lability of biomembranes and their components. III. Kinetics of complex formation between bovine serum albumin molecules and higher saturated fatty acids]. / II. Kinetika kompleksoobrazovaniia mezhdu molekulami syvorotochnogo al'bumina byka i vysshimi predd'nymi zhirnymi kislotami

Kinetic peculiarities of the sorption of natural limited fatty acids on the molecules of bovine serum albumine (BSA) were studied by investigating fluorescent parameters of ionic (1-anilinonaphtalin-8-sulphonate-ANS) and neutral (N-phenyl-1-naphtylamine-PNA) probes. The following regularities were found: 1. The parameters which characterize the microsurroundings of both probes (quantum yield of fluorescence, the binding constant) did not change significantly during the sorption of the fattyn acids (laurinic, palmitinic and methyl ether of the stearinic acid). An exponential character of BSA fluorescent titration with fatty acids points to a competitive character of the relationship dye -- fatty acid for the binding sites in hydrophobic sacks of BSA. 2. The study of the character of the effect of solution ionic strength on the sorption of fatty acids showed that along with hydrophobic interactions the electrostatic interaction between carboxyl residues of fatty acids and charged protein groups also significantly contributed to this process. 3. Temperature relationship of AMS and PNA fluorescence intensity in the complex BSA -- laurinic acid correlates well with temperature relationship obtained from a pure protein system.

[Free-radical oxidation of biological membrane lipids. V. Fluorescence of fatty acids and phospholipids]. / Svobodnoradikal'noe okislenie lipidov biologicheskikh membran. V. Fluorestsentsiia zhirnykh kislot i fosfolipidov

The nature of fluorescence in UV and visible apectrum region of autooxidizing unsaturated fatty acids and phospholipids was partially determined by UV-adsorption, polarography in the system of organic solvents and thin layer chromatography.