Evaluation of transcriptional fusions with green fluorescent protein versus luciferase as reporters in bacterial mutagenicity tests.
A bacterial plasmid was constructed on which the regulatory region of the umuC gene of Escherichia coli was fused to the coding sequence of the green fluorescent protein gene (gfp) from the jellyfish Aequorea victoria. Escherichia coli AB1157 strains carrying the plasmid emitted fluorescence in the presence of mutagens that induce the SOS DNA repair system. Data on tests with nitrosoguanidine, methylmethane sulphonate and UV radiation (254 nm) are presented. Although fluorescent detection using this system was not as rapid or sensitive as a similar luminescent equivalent (umuC-luxAB), the gfp reporter system was more robust. Escherichia coli umu gene induction was also analysed in Salmonella typhimurium TA1537 cells following plasmid transfer and exposure to the same range of mutagens. There was no significant difference in sensitivity between the two species. These preliminary results will provide the basis for development of mutagenicity test systems useful in the testing of complex mixtures, such as environmental samples, and the investigation of physiological parameters influencing spontaneous mutagenesis in bacteria.
Justus
T
T
School of Biological Sciences, The Flinders University of South Australia, GPO Box 2100, Adelaide, SA 5001, Australia.
Thomas
S M
SM
D000818:Animals; D019677:Artificial Gene Fusion; D001419:Bacteria / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000528:radiation effects; D001426:Bacterial Proteins / Q000235:genetics*; D004259:DNA-Directed DNA Polymerase; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins; D005453:Fluorescence; D017930:Genes, Reporter / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D049452:Green Fluorescent Proteins; D008156:Luciferases / Q000737:chemistry* / Q000235:genetics; D008163:Luminescent Measurements; D008164:Luminescent Proteins / Q000737:chemistry* / Q000235:genetics; D008741:Methyl Methanesulfonate / Q000633:toxicity; D009152:Mutagenicity Tests / Q000379:methods*; D009153:Mutagens / Q000633:toxicity; D009604:Nitrosoguanidines / Q000633:toxicity; D013014:SOS Response, Genetics / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D012486:Salmonella typhimurium / Q000235:genetics; D037401:Scyphozoa; D014466:Ultraviolet Rays / Q000009:adverse effects
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008164:Luminescent Proteins; D009153:Mutagens; D009604:Nitrosoguanidines; D049452:Green Fluorescent Proteins; C078202:UmuC protein, E coli; D008741:Methyl Methanesulfonate; D008156:Luciferases; D004259:DNA-Directed DNA Polymerase