UV and arsenate toxicity: A specific and sensitive yeast bioluminescence assay

Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beersheba, 84105, Israel.
Cell Biology and Toxicology (Impact Factor: 2.68). 03/2011; 27(3):227-36. DOI: 10.1007/s10565-011-9184-8
Source: PubMed


We describe a Saccharomyces cerevisiae bioluminescence assay for UV and arsenate in which bacterial luciferase genes are regulated by the promoter of the yeast gene, UFO1. UFO1 encodes the F-box subunit of the Skp1–Cdc53–F-box protein ubiquitin ligase complex and is induced by DNA damage and by arsenate. We engineered the UFO1 promoter into an existing yeast bioreporter that employs human genes for detection of steroid hormone-disrupting compounds in water bodies. Our analysis indicates that use of an endogenous yeast promoter in different mutant backgrounds allows discrimination between different environmental signals. The UFO1-engineered yeast give a robust bioluminescence response to UVB and can be used for evaluating UV protective sunscreens. They are also effective in detecting extremely low concentrations of arsenate, particularly in pdr5Δ mutants that lack a mechanism to extrude toxic chemicals; however, they do not respond to cadmium or mercury. Combined use of endogenous yeast promoter elements and mutants of stress response pathways may facilitate development of high-specificity yeast bioreporters able to discriminate between closely related chemicals present together in the environment.

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    • "Since this bioassay is luc-based, D-luciferin must be added. Another S. cerevisiae-based bioreporter has been created to measure arsenate and also UV damage (Bakhrat et al., 2011). This strain is based on the BLYES strain of Sanseverino et al. (2005), containing a constitutive luxCDEfrp plasmid and a luxAB plasmid that has been reengineered to be under control of the UFO1 promoter, which specifically responds to DNA damage by UV light and also arsenate. "

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