Detection of endocrine disruptors combining a yeast-based sensor system with high-performance thin layer chromatography

A wide range of hazardous chemicals are released into the aquatic environment through wastewater treatment plants (WWTP), landfills and agricultural activities. Some of these chemicals possess endocrine-disrupting properties, meaing that they can mimic, disturb or block the endogenous endocrine system.

The yeast Saccharomyces cerevisiae provides an ideal biological platform for detecting environmental steroid hormones and their analogues, as it lacks steroid receptors of its own. We designed a battery of fluorescent yeast strains which express either the human estrogen receptor alpha (ERα) or androgen receptor (AR). Upon binding the ERα- or AR-ligand complexes to the specific hormone response element, each of the yeast strains expresses green, red or blue fluorescent proteins. We used these whole-cell bioreporters to identify and quantify endocrine disrupting compounds in environmental samples. By coupling this biological assay with high-performance thin layer chromatography (HPTLC), a standard method for EDCs separation, we can screen multiple compounds simultaneously.

We posit that the combination of a chemical separation technique with an optical yeast-based bioassay may be a valuable addition to current chemical detection methods in the environment. This combination allows us to detect compounds with hormonal-related bioactivity from within complex samples, alleviating the need for chemical analysis of the entire sample. Moreover, by combining different reporter proteins, we are able to detect multiple EDC groups in a single assay, making the procedure more robust and cost-effective.