[Antialcoholic properties of a subalin probiotic drug].

Efficiency of a subalin probiotic drug created on the basis of live microbic cultures was investigated, at acute alcoholic intoxication developed in experimental animals. It was shown that after one time administration of this drug to animals there was no considerable influence on activity of the main enzymes of ethanol metabolism--alcohol- and aldehyde dehydrogenase both in animals with an alcoholic intoxication and without. However subalin induced considerable changes in the quantitative maintenance of acetaldehyde in blood of animals with alcoholic intoxication, which concentration decreased almost in 20 times.

[Anti-alcoholic and anti-narcotic action of Methylobacteriim extorquens UCM B-3368].

The paper deals with action efficiency of microbial biomass on characteristic indicators at alcohol and morphine organism intoxication. The investigated microbial biomass affects the regulatory biochemical and physiological systems in experimental animals, normalizes activity of alcohol dehydrogenase and aldehide dehydrogenase, as well as the content of dophamine, disturbed under the effect of alcohol and morphine. Thus, the organism intoxication decreases. Except for the specific action, the above microbial biomass can be a source of protein, aminoacids, vitamins, microelements. So, the microbial preparation, made on its basis, can be used for the treatment of alcohol and morphine dependence in a form of biologically active dope. Thus the microbial drug intended for treatment of alcohol and opium dependence has been developed. One of its action mechanisms is based on the microorganisms capacity to transform alcohols and aldehides, owing to availability of alcohol and aldehide dehydrogenase, other its action mechanisms are at the stage of investigation.

[Role of exogenous carbon dioxide in the metabolism of methane-oxidizing bacteria]. / Rol' ékzogennoi uglekisloty v metabolizme metanokisliaiushchikh bakterii.

The object of this work was to study the ability of methane oxidizing bacteria to use CO2 as an acceptor of electrons liberated in methane oxidation and the role of CO2 fixation in the constructive metabolism of the bacteria. All of the studied methane oxidizing bacterial cultures were found to be capable of fixing the 14C of hydrocarbonate. The activity of the process was shown to be similar in different strains. Up to 30% of the carbon in the biomass composition could originate from the carbon of HCO3-. Methane oxidizing bacteria that assimilated C1-compounds via the hexulose phosphate and serine pathways had the same level of HCO3- fixation. No differences were found among strains of the same species, among species, or among genera. The assimilation of HCO3- was catalyzed by PEP-carboxylase (i. e. in a heterotrophous way) or, in some cultures, by ribulose-1,5-diphosphate carboxylase, the key enzyme in the autotrophous pathway of CO2 assimilation. The enzymological mechanisms of HCO3- assimilation are discussed. The biological role of CO2 fixation in the metabolism of methane oxidizing bacteria that use the hexulose phosphate and serine pathways of methane assimilation may be different. The process can either play the role of anapleurotic reactions in the tricarboxylic acid cycle, or be an element of the serine pathway of methane assimilation. Calculations have shown that the extent to which a substrate to be metabolized is reduced seems to determine the activity of exogenous CO2 fixation. The contribution made by HCO3- fixation into the carbon metabolism of methane oxidizing bacteria confirms that they are related to lithotrophous organisms.

[Theoretical evaluation of necessity of carbon dioxide assimilation by microorganisms during growth on various substrates]. / Assimiliatsiia uglekisloty mikroorganizmami pri roste na razlichnykh substratakh.

The biological role of exogenous carbon dioxide during substrate assimilation with a various degree of reductivity is evaluated. The investigation of metabolic pathways of carbon dioxide incorporation into the metabolic processes of methaneoxidizing bacteria shows that the HCO3- ion assimilation is catalyzed by phosphoenolpyruvate carboxylase and in certain strains also by the key enzyme of autotrophic pathway of the carbon dioxide assimilation, ribulose-1,5-diphosphate carboxylase. The theoretical calculations and experimental studies indicate that exogenous carbon dioxide is a necessary participant of the metabolic processes of methane or methanol assimilation. It is also an acceptor of the excess electrons of these compounds. It is the degree of reductivity of the substrate metabolized that determines the activity of the exogenous carbon dioxide fixation by microorganisms. The carbon dioxide fixation by heterotrophic microorganisms must be considered, therefore, as a process which is mostly due to the elementary composition of the source of carbon under conversion.

[Diauxotrophic properties of microorganisms assimilating C2--C4 hydrocarbons]. / Diauksotrofnye svoistva mikroorganizmov, assimiliruiushchikh uglevodorody C2--C4.

Diauxotrophic properties of bacteria assimilating gaseous hydrocarbons C2--C4 and other complex organic substances but not methane were studied. If the medium contained two substrates (hydrocarbon+carbohydrate), the non-growing cells of the strains did not display diauxotrophic properties. In the phase of exponential growth, oxygen-containing carbon sources and then gaseous hydrocarbons were assimilated, i.e. diauxia was observed. If a microbial association containing an obligate methylotroph and a facultative gas-assimilating culture was grown on a medium with a natural gas, the latter culture assimilated carbon-containing metabolites of the methylotroph and then, when their concentration decreased, gaseous hydrocarbons. The order in which complex organic substances (exometabolites of methylotrophs) and hydrocarbons C2--C4 were assimilated was determined by their concentration in the medium. In the course of growth of such a microbial association, the inhibiting effect of metabolites of methylotrophs on their growth decreased as well as the loss of methane being transformed by methylotrophs into exometabolites, and hydrocarbons C2--C4 were utilized.

[Mechanism of methane oxidation by intact cells of obligate methylotrophs]. / O mekhanizme sookisleniia étana intaktnymi kletkami obligatnykh metilotrofov

Ethane and propane were found to be competitive inhibitors of methane oxidation. Obligate methylotrophs can oxidize ethane only in the presence of methane, i.e. co-oxidation of ethane takes place. Studies on the kinetics of simultaneous oxidation of ethane and methane have shown that their oxidation is catalysed by one and the same enzyme system, within one and the same enzyme active site; therefore, the absolute substrate specificity is absent. The reactions of methane and ethane oxidation are coupled since ethane can be oxidized only after the reduced coenzyme had been provided by the reaction of methane oxidation.