[Effect of heavy water on metabolism of a symbiotic organism]. / Vliianie tiazheloi vody na metabolizm simbioticheskogo organizma.

The metabolism of the symbiotic organism medusomycete (tea fungus) and the influence of D2O on its development was studied by high-resolution NMR methods using isotopically enriched (by 13C and 2H) metabolites. The results demonstrate that D2O influences the selective utilization of certain protonated substrates during the formation of triose phosphates. It was found that protonated isotopomers derived from the first glucose fragment C1-C2-C3 are predominantly utilized. This explains why the metabolism slows down by a factor of 2 to 3 if D2O concentration in the medium increases. It was also shown that approximately 10% of the organisms are in the state of dynamic extracellular endosymbiosis. This state is characterized by the ability to exchange the metabolic products through close intercellular contacts. As a result of the metabolic exchange, a multicellular organism is formed, with metabolic elements localized in different partners. A distinguishing feature of this organism is the ability to accumulate the internal resources of carbon, thus making it better adapted to the unfavorable environment.

[Medusomyces (tea fungus): scientific history, composition, physiology, and metabolism]. / Meduzomitset (chainyi grib): nauchania istoriia, sostav, osobennosti fiziologii i metabolizma.

The literature data on medusomyces published since 1913 are discussed. Different versions of appearance and distribution of this microorganism are considered. The features of its structure, metabolism and growth conditions are analyzed. It is shown that the tea fungus is a symbiosis is of several sorts of yeast and acetic acid bacteria. Evidence is presented indicating that fermented tea fungus has a therapeutic effect and can be applied in medicine. It was proved, that the antimicrobial properties of tea fungus metabolic products are due to the presence of particular antibiotic substances. The regularities of the biosynthesis of these substances and the pathways of its stimulation were studied. The results obtained will lead to the large-scale use of tea fungus in biotechnology. The fungus has unique adaptation properties, as confirmed by experiments on cultivation of the organism on deuterium oxide (D2O) and in the conditions of "cold stress". It is suggested that medusomyces is a unique model for the investigation of the phenomenon of symbiosis.

[Pathways of inclusion of isotopes 2H and 13C into exometabolites in course of glucose utilization by medusomycete]. / Analiz putei vkliucheniia izotopov 2H i 13C v ékzometabolity v khode utilizatsii gliukozy meduzomitsetom.

The inclusion of 2H and 13C isotopes into the products of glucose utilization by medusomycete during its growth on deuterated media was studied by high-resolution NMR spectroscopy. Both unlabeled and 13C-labeled (in positions 1, 2, 6) glucose was used. It was shown that the glucose utilization proceeds by the classical Embden-Meyerhof-Parnas pathway. The incorporation of deuterium to the methyl group of ethanol can occur only during glucose-fructose-6-phosphate and phosphoenolpyruvate--pyruvate conversion. None of these stages by themselves is responsible for the existing distribution of deuterium atoms. The maximum inclusion of deuterium to the methyl group is no more than two atoms for the first glucose fragment (C1-C2-C3) and no more than one, for the second fragment (C4-C5-C6). The methylene group of ethanol is more accessible for deuterons because the proton surroundings of carbon atoms C2 and C5 completely changes. It was concluded that the maximum proton exchange occurs at positions C2 and C5; at positions C1, the proton exchange is lesser, and at position C6 it is the least. It was also shown that about 10% C1-C3 of triose leave the glycolysis cycle and are used in other processes.

[Identification of minor components of medusomycete exometabolites. 1H-NMR spectra in 13C and deuterium substitutions]. / Identifikatsiia minornykh komponentov ékzometabolitov meduzomitseta. Osobennosti 1H-IaMR spektrov pri nekotorykh zameshcheniiakh 13C i deiteriia.

High-resolution 1H-NMR experiments were performed on 2H/13C isotopically labelled metabolites of growing medusomycete culture. Some minor metabolites were identified and the degree of their deuterization was established. Some of these metabolites were shown to be present in isomeric forms. Our results demonstrated that glycerol was produced in the growth medium on the early stage of the system adaptation to the growth in D2O.

[Identification of partially deuterated exometabolites during culture of tea fungi in heavy water]. / Idenktifikatsiia chastichno deiterirovannykh ékzometabolitov pri kul'tivirovanii chainogo griba v tiazheloi vode.

Exometabolites of tea fungus during the cultivation on heavy water were studied by methods of high-resolution proton and deuterium exchange. Is was shown that, depending on the degree of exchange of proton for deuterium in the methyl group of acetate, three isotopomers exist: -CH3, -CH2D, and -CHD2. Ethanol is represented by six isotopomers: -CHD-CH3, -CD2-CH3, -CD2-CH2D, -CD2-CHD2, -CHD-CH2D, and -CHD-CHD2. Relative concentration of these isotopomers and the percent content of deuterium were determined. Based on these data, the kinetics of metabolism of the object cultivated on heavy water was analyzed. It was show that the efficiency of glucose utilization is the same as during cultivation on light water with the exception that the time of utilization is significantly greater. At the same time, the parameters of utilization of ethanol and its conversion into acetic acid in the life activity of the tea fungus in heavy and light water are very similar.

[The use of 1H-NMR spectroscopy for the study of cell cultures]. / Primenenie 1H-IaMR spektroskopii dlia issledovaniia kul'tur kletok.

Production of lactate by the HSR-1, HSR-8, HET-SR fibroblasts have been investigated by 1H-NMR method. Were investigated both monolayer cell cultures and cells immobilized in collagen lattice. Represented data demonstrate the possibility of the NMR-spectroscopy to investigate growth's processes in the cell cultures.