Microscale application of the SOS-LUX-TEST as biosensor for genotoxic agents

The bacterial biodetection system SOS-LUX-TEST has been developed for rapid detection of environmental genotoxins, This cellular bioassay is based on the receptor reporter principle with the SOS system as receptor sensitive t o DNA damage and the bioluminescence system giving the optical signal which is registered by an appropriate detector. The lux-operon of a marine photo bacteria (Photobacterium leiognathi) containing the whole information for t he synthesis of the bacterial luciferase and its substrate was cloned downs tream of a SOS-controlled promoter and introduced on a plasmid into E. coli , This system reacts in a dose-dependent manner with bioluminescence to any agent like radiation or chemicals which produce damages to the DNA molecul es inside these cells. For the measurements of the genotoxic potential of c hemical compounds a microplate luminometer was employed which allows contin uous incubation and shaking during the registration of the signal. The kine tics of bioluminescence was always monitored over a period of at least 5 h. Typical model compounds with various DNA damaging potencies were tested. ( C) 1999 Elsevier Science B.V. All rights reserved.