Abstract
Genetically modified bacteria, engineered to generate a quantifiable signal in response to pre-determined sets of environmental conditions, may serve as combined sensing/reporting elements in whole-cell biosensors. We have compared two of the several available reporter genes in such cells: green fluorescent proteins (GFPs) (Aquorea victoria gfp) and bioluminescence (Vibrio fischeri luxCDABE) genes, fused to either SOS (recA) or heat shock (grpE) promoters. In both cases, bacterial bioluminescence allowed faster and more sensitive detection of the model toxicants; the fluorescent reporter proteins were much more stable, and following long-term exposure allowed detection at levels similar to that of the bioluminescent sensors. From the two green fluorescent proteins tested, enhanced GFP (EGFP) displayed a more rapid response and higher signal intensity than GFPuv. To combine the advantages of both reporter functions, representatives of both types were jointly encapsulated in a sol-gel matrix and immobilized onto a glass surface, to generate a bioluminescent toxicity and a fluorescent genotoxicity sensor. The dual-function sensor detected both toxic and genotoxic model compounds with no interference from the co-immobilized member.
Original language | English |
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Pages (from-to) | 2-8 |
Number of pages | 7 |
Journal | Sensors and Actuators, B: Chemical |
Volume | 90 |
Issue number | 1-3 |
DOIs | |
State | Published - 20 Apr 2003 |
Event | Proceedingsof the 6th european Conference on Optical Chemical - Manchester, United Kingdom Duration: 7 Apr 2002 → 7 Apr 2002 |
Bibliographical note
Funding Information:Research was supported by DARPA grant number N00173-01-1-G009, by a research grant from the Land Niedersachen Min. f. Wissenchaft & Kultur (Germany) 16 November 1998—25 A.5—76 251-99-2/98 (ZN549) and by the Israeli Ministry of Science, Culture and Sport (Infrastructure grant 1319-1-98 and the France–Israel Cooperative Research Program). We are grateful to U. Alon, T. Van Dyk and R.A. LaRossa for gifts of strains and plasmids.
Keywords
- Bioluminescence
- Escherichia coli
- Fluorescence
- Genotoxicity
- Green fluorescent protein
- Sol-gel
- Toxicity