A flow cytometry-optimized assay using an SOS-green fluorescent protein (SOS-GFP) whole-cell biosensor for the detection of genotoxins in complex environments

Research output: Contribution to journalJournal articlepeer-review

Whole-cell biosensors have become popular tools for detection of ecotoxic compounds in environmental samples. We have developed an assay optimized for flow cytometry with detection of genotoxic compounds in mind. The assay features extended pre-incubation and a cell density of only 106-107 cells/mL, and proved far more sensitive than a previously published assay using the same biosensor strain. By applying the SOS-green fluorescent protein (GFP) whole-cell biosensor directly to soil microcosms we were also able to evaluate both the applicability and sensitivity of a biosensor based on SOS-induction in whole soil samples. Soil microcosms were spiked with a dilution-series of crude broth extract from the mitomycin C-producing streptomycete Streptomyces caespitosus. Biosensors extracted from these microcosms after 1 day of incubation at 30 °C were easily distinguished from extracts of non-contaminated soil particles when using flow cytometry, and induction of the biosensor by mitomycin C was detectable at concentrations as low as 2.5 ng/g of soil.
Original languageEnglish
JournalMutation Research - Reviews
Volume603
Issue number2
Pages (from-to)164-172
Number of pages9
ISSN1383-5742
DOIs
Publication statusPublished - 2006

Bibliographical note

Keywords: SOS-response; Green fluorescent protein (GFP); Whole-cell biosensor; Flow cytometry; Genotoxicity; Mitomycin C; Soil microcosms

ID: 1913435