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Here, we present a new lux-biosensor based on Bacillus subtilis for detecting of DNA-tropic and oxidative stress-causing agents. Hybrid plasmids pNK-DinC, pNK-AlkA, and pNK-MrgA have been constructed, in which the Photorhabdus luminescens reporter genes luxABCDE are transcribed from the stress-inducible promoters of B. subtilis : the SOS promoter P dinC , the methylation-specific response promoter P alkA , and the oxidative stress promoter P mrgA . The luminescence of B. subtilis- based biosensors specifically increases in response to the appearance in the environment of such common toxicants as mitomycin C, methyl methanesulfonate, and H 2 O 2 . Comparison with Escherichia coli -based lux-biosensors, where the promoters P dinI , P alkA , and P dps were used, showed generally similar characteristics. However, for B. subtilis P dinC , a higher response amplitude was observed, and for B. subtilis P alkA , on the contrary, both the amplitude and the range of detectable toxicant concentrations were decreased. B. subtilis P dinC and B. subtilis P mrgA showed increased sensitivity to the genotoxic effects of the 2,2'-bis(bicyclo [2.2.1] heptane) compound, which is a promising propellant, compared to E. coli -based lux-biosensors. The obtained biosensors are applicable for detection of toxicants introduced into soil. Such bacillary biosensors can be used to study the differences in the mechanisms of toxicity against Gram-positive and Gram-negative bacteria.