title: The combined bacterial Lux-Fluoro test for the detection and quantification of genotoxic and cytotoxic agents in surface water: results from the "Technical Workshop on Genotoxicity Biosensing".
abstract: The bioassay Lux-Fluoro test was developed for the rapid detection and quantification of environmental pollutants with genotoxic and/or cytotoxic potential. This bacterial test system uses two different reporter genes whose gene products and their reactions, respectively, can be measured easily and simultaneously by optical methods. Genotoxicity is measured by the increase of bioluminescence in genetically modified bacteria which carry a plasmid with a complete lux operon for the enzyme luciferase from the marine photobacterium P. leiognathi under the control of a DNA-damage dependent so-called SOS promoter. If the deoxyribonucleic acid in these bacteria is damaged by a genotoxic chemical, the SOS promoter is turned on and the lux operon is expressed. The newly synthesized luciferase reacts immediately with its substrate thereby producing bioluminescence in a damage-proportional manner. In the second part of the system, genetically modified bacteria carry the gene for the green fluorescent protein (gfp) from the jellyfish Aequora victoria downstream from a constitutively expressed promoter. These bacteria are fluorescent under common growth conditions. If their cellular metabolism is disturbed by the action of cytotoxic chemicals, the fluorescence decreases in a dose-proportional manner. The combined Lux-Fluoro test is shown to be well suited for the biological assessment of the geno- and cytotoxicity of a series of model agents and environmental samples at the Technical Workshop on Genotoxicity Biosensing (TECHNOTOX).
authors.affiliation: Radiation Biology, Institute of Aerospace Medicine, German Aerospace Center (DLR), Linder Höhe, 51147 Köln, Germany. christa.baumstark-khan@dlr.de
authors.forename: Christa
authors.initials: C
authors.lastname: Baumstark-Khan
authors.forename: Elke
authors.initials: E
authors.lastname: Rabbow
authors.forename: Petra
authors.initials: P
authors.lastname: Rettberg
authors.forename: Gerda
authors.initials: G
authors.lastname: Horneck
mesh_terms: D015415:Biomarkers / Q000032:analysis; D015374:Biosensing Techniques; D003603:Cytotoxins; D004249:DNA Damage / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D049452:Green Fluorescent Proteins / Q000737:chemistry; D008156:Luciferases / Q000032:analysis* / Q000378:metabolism; D049453:Luciferases, Bacterial / Q000032:analysis / Q000378:metabolism; D008163:Luminescent Measurements; D009152:Mutagenicity Tests; D010776:Photobacterium / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D011401:Promoter Regions, Genetic; D013014:SOS Response, Genetics / Q000187:drug effects* / Q000502:physiology; D013997:Time Factors; D014873:Water Pollutants / Q000032:analysis / Q000633:toxicity; D014881:Water Supply
chemical_list: D015415:Biomarkers; D003603:Cytotoxins; D014873:Water Pollutants; D049452:Green Fluorescent Proteins; D008156:Luciferases; D049453:Luciferases, Bacterial