[Effect of space flight conditions on properties of hydrocarbon-oxidizing bacteria]. / Vliianie uslovii kosmicheskogo poleta na svoistva uglevodorodokisliaiushchikh bakterii.

Results of experiments on the Mir space station (EO-25 and EO-26) demonstrated that the conditions of orbital flight, primarily the cosmic radiation, was a mutagenic factor affecting both the genotype and phenotype of an oil-oxidizing bacterial strain, Mycobacterium flavescens EX-91. The emerging mutants differed from original culture by the rate of colony growth and the ability to ferment certain carbohydrates or synthesize beta-galactosidase. Changes in the rate of utilization of raw oil and individual hydrocarbon types (constituting model mixtures) suggest that cosmic radiation may serve as a means of obtaining mutant clones of microorganisms with new properties.

[Development and testing of "Ekosorb" biosorbent based on association of petroleum-oxidizing bacteria for purifying petroleum-polluted soils]. / Razrabotka i ispytaniia biosorbenta "Ekosorb" na osnove assotsiatsii nefteokisliaiushchikh baketerii dlia ochistki neftezagriaznennykh pochv.

A biosorbent containing an association of oil-oxidizing bacteria as a main constituent was developed, in which Lessorb, a product of moss and wood thermal processing, was used as a carrier. Xeroprotectors preserving the cell viability and oil-oxidizing activity in the biosorbent on drying and after long-term storage were selected. The use of this biosorbent for cleaning oil-polluted sod-podzol soils showed a two-threefold cleanup rate acceleration at different pollution levels (8 and 24 l/m2), especially in the presence of a nitrogen-phosphate fertilizer. The biosorbent increased the populations of certain groups of soil microorganisms and the total soil biological activity.

[Creation and use of a liquid substance based on association of petroleum-oxidizing bacteria]. / Sozdanie i primenenie zhidkogo preparata na osnove assotsiatsii nefteokisliaiushchikh bakterii.

An association of four bacterial strains with high oil-oxidizing and bioemulsifying activities, psychrophilicity, resistance to chemical pollutants, and lack of pathogenicity was selected from a collection of natural oil-oxidizing microorganisms. A new liquid preparation containing stabilizers and preservatives that maintain the cell viability and oil-oxidizing activity during long-term storage was developed. A field experiment in oil-polluted sod-podzol and clay sand soils demonstrated that this preparation accelerated the biodegradation of oil and its individual fractions, especially in the presence of mineral and organic fertilizers. Treatment of oil-polluted soil with this preparation and additives decreased the oil-induced suppression of certain groups of soil microflora.

[Plasmid preservation in Escherichia coli cells in batch and continuous cultivation]. / Sokhranenie plazmid v kletkakh kishechnoi palochki pri periodicheskom i nepreryvnom kul'tivirovanii.

The growth kinetics of plasmid and nonplasmid strains of 2 isogenic E. coli K12 culture lines has been studied in experiments on batch and continuous cultivation. Under the optimum conditions the growth rate of R+- and R- cells is the same; under the conditions of limited glucose supply the plasmid strains grown slower, as their energy is partly spent on maintaining plasmids in the cell.

[Carbon assimilation pathways in the methylotrophy of Pseudomonas gazotropha]. / Puti assimiliatsii ugleroda pri metilotrofii Pseudomonas gazotropha.

The dynamics of label distribution was studied in the products of 14CH3OH assimilation by the cells of Pseudomonas gazotropha Z-1156. Substances to be first detected were glycolate, glycine and those of the chromatogram "start" spot. Later, the radioactivity was detected in phosphorylated compounds and glycerate. Cell extracts of Ps. gazotropha Z-1156 contained ribosephosphate isomerase, phosphoribulokinase and glyceraldehyde dehydrogenase but not ribulosediphosphate carboxylase. Distribution of the label in the products of 14CH3OH assimilation and the presence of active hydroxypyruvate reductase in the extract suggest that the serine cycle is involved in methylotrophy of Ps. gazotropha Z-1156. This suggestion is confirmed by the presence of active formate dehydrogenase, phosphoenolpyruvate carboxylase, (NADP+, Mn2+)-specific isocitrate dehydrogenase, (NAD, Mg2+)-specific malate dehydrogenase, malate lyase, and isocitrate lyase. The citric acid cycle is open at the alpha-ketoglutarate dehydrogenase system. The dry biomass of Ps. gazotropha Z-1156 contains over 70% of protein.