title: Microbial sensors of ultraviolet radiation based on recA'::lux fusions.
abstract: Escherichia coli strains containing plasmid-borne fusions of the recA promoter-operator region to the Vibrio fischeri lux genes were previously shown to increase their luminescence in the presence of DNA damage hazards, and thus to be useful for genotoxicant detection. The present study expands previous work by demonstrating and investigating the luminescent response of these strains to ultraviolet radiation. Several genetic variants of the basic recA'::lux design were examined, including a tolC modification of membrane efflux capacity, a chromosomal integration of the recA'::lux fusion, a different lux reporter (Photorhabdus luminescens instead of V. fischeri, allowing the assay to be run at 37 degrees C), and a different host bacterium (Salmonella typhimurium instead of E. coli). Generally, two modifications provided the fastest responses: the use of the S. typhimurium host or the P. luminescens lux reporter. Highest sensitivity, however, was demonstrated in an E. coli strain in which a single copy of the V. fischeri lux fusion was integrated into the bacterial chromosome.
authors.affiliation: Fredy and Nadine Herrmann Graduate School of Applied Science, Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: R
authors.initials: R
authors.lastname: Rosen
authors.forename: Y
authors.initials: Y
authors.lastname: Davidov
authors.forename: R A
authors.initials: RA
authors.lastname: LaRossa
authors.forename: S
authors.initials: S
authors.lastname: Belkin
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D015374:Biosensing Techniques / Q000295:instrumentation*; D002875:Chromosomes / Q000235:genetics / Q000528:radiation effects; D004247:DNA / Q000528:radiation effects; D004249:DNA Damage / Q000187:drug effects / Q000528:radiation effects; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D004926:Escherichia coli / Q000235:genetics / Q000528:radiation effects; D017930:Genes, Reporter; D007700:Kinetics; D009154:Mutation; D009268:Nalidixic Acid / Q000494:pharmacology; D020637:Photorhabdus / Q000235:genetics; D010957:Plasmids / Q000378:metabolism; D011938:Rec A Recombinases / Q000235:genetics*; D012486:Salmonella typhimurium / Q000378:metabolism; D013696:Temperature; D013997:Time Factors; D059005:Topoisomerase II Inhibitors; D014157:Transcription Factors / Q000235:genetics*; D014466:Ultraviolet Rays; D014733:Vibrio / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; C085427:LuxI protein, Bacteria; D059005:Topoisomerase II Inhibitors; D014157:Transcription Factors; D009268:Nalidixic Acid; D004247:DNA; D011938:Rec A Recombinases