Test-system based on the Vibrio fischeri Lux regulon for studying functional activity of the Escherichia coli protease Lon and its mutant forms

The possibility of application of the bioluminescence method (Lux-test) for studying in vivo functional activity of Escherichia coli pretense Lon and its mutants was demonstrated. This assay is based on the capacity of protease Lon and its mutant forms for specific degradation of the LuxR protein, a positive transcriptional activator of the right operon luxICDABE from the marine bacterium Vibrio fischeri, and thus to affect the level of AB luciferase in the cells. A correlation between in vitro activity of the protease Lon mutants and the intensity of bioluminescence measured by the Lux-test was revealed.