Specific Lux Biosensors of Escherichia coli Containing pRecA::lux, pColD::lux, and pDinI::lux Plasmids for Detection of Genotoxic Agents

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.