It was shown that the studied petroleum products, kerosene and gasoline, contain microfloccules of heterogeneous microbial biofilms, the cells of which are integrated in a polymer matrix containing acidic polysaccharides. Thirteen bacterial strains were microbiologically isolated from petroleum products, and their taxonomy was identified via analysis of the 16S rRNA sequence. Kerosene was characterized by a diverse bacterial composition, including the following genera: Sphingobacterium, Alcaligenes, Rhodococcus, and Deinococcus. The gasoline bacterial community included only two genera: Bacillus and Paenibacillus. Representatives of the Deinococcus genus that are capable of growing on hydrocarbons were isolated from fuels for the first time. Strains isolated from gasoline (Bacillus safensis Bi13 and Bacillus sp. Bi14) proved to be the most effective biodegraders of all n-alkanes, isoalkanes, cycloalkanes, alkenes, and aromatic hydrocarbons, whereas the strain Rhodococcus erythropolis Bi6, which was isolated from kerosene, effectively decomposed only n-alkanes and trimethylbenzene. Both types of the studied petroleum products contained hydrocarbonoxidizing communities, some members of which were more active in hydrocarbon biodegradation, while others were capable of producing biosurfactants and compounds with emulsifying activity (Deinococcus sp. Bi7) or had increased (well above average) cell-wall hydrophobicity (Sphingobacterium sp. Bi5 from kerosene; Bacillus pumilus Bi12 from gasoline). The indicated properties of the studied strains make them promising for use in bioremediation.

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A consortium of microorganisms were isolated from TC-1 fuel form, each member of which is capable of consistently degrade hydrocarbons’ different fractions. The 5 strains of hydrocarbon-oxidizing bacteria (PSB) were identified and isolated from TS-1 jet fuel. Their physiological and biochemical features are defined. All strains exhibit positive catalase activity. It is determined that all UOB strains, producing exogenous and endogenous surfactants, are capable to growth on media with different fraction of hydrocarbons. The study of these associations allows to create effective preparations for bioremediation in the elimination of accidental spills of oil and petroleum products.

The lux biosensor of E. coli MG1655 (pDinI::lux) was constructed and a comparative study of the SOS response of three biosensors E. coli MG1655 (pRecA::lux), E. coli MG1655 (pColD::lux), and E. coli MG1655 (pDinI::lux) under the action of genotoxic agents was performed. The listed biosensors were named, respectively, PRecA, PColD, and PDinI. The response amplitude (RA) was chosen as an indicator of the SOS response level of lux biosensors. It was shown that RA of the PDinI biosensor was more expressed than RA of the PRecA biosensor under the action of hydrogen peroxide, alkylating agents such as NMU, MMS, and streptozotocin, antibacterial agent such as dioxidine, and cytostatics such as mitomycin C and cisplatin. Antimetabolite 5-fluorouracil showed activity only with PDinI. Furacilin and 4-NQO, whose metabolites form adducts with DNA, were more active on PColD than on PRecA and PDinI. DNA gyrase inhibitors such as nalidixic acid and ciprofloxacin were less active on PDinI than on PColD and PRecA. Overall, among 13 tested substances, 8 more actively induced SOS response in the PDinI biosensor than in PColD and PRecA. At the same time, 5-fluororacil induced SOS response only with the PDinI biosensor. It was concluded that the PDinI biosensor can be successfully used for the primary detection of potential genotoxicants by their ability to induce SOS response in E. coli cells.