title: A novel estrogen sensor based on recombinant Arxula adeninivorans cells.
abstract: A novel yeast cell-based assay was developed for the detection of estrogenic activity in wastewater. Recombinant Arxula adeninivorans strains were engineered to co-express the human estrogen receptor alpha (hERalpha) and a Klebsiella-derived phytase (phyK) reporter gene under the control of an A. adeninivorans-derived glucoamylase (GAA) promoter which had been modified by the insertion of estrogen-responsive elements (EREs). In the presence of estrogenic compounds, hERalpha dimerizes and binds to the estrogen. Reporter gene expression is induced by subsequent binding of the hERalpha-dimer/estrogen complex to estrogen responsive elements (ERE) in the promoter. The insertion of different numbers of EREs in three alternative promoter positions and its effect on reporter gene expression were assessed. In one of the constructs, a detection limit of 5 ng l(-1) and a determination limit of 10 ng l(-1) for 17beta-estradiol-like activity was achieved. The photometric assay used enabled estrogen determination in sewage samples within 30 h.
authors.affiliation: Institut für Pflanzengenetik und Kulturpflanzenforschung, Corrensstr. 3, D-06466 Gatersleben, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hahn
authors.forename: Kristina
authors.initials: K
authors.lastname: Tag
authors.forename: Klaus
authors.initials: K
authors.lastname: Riedel
authors.forename: Steffen
authors.initials: S
authors.lastname: Uhlig
authors.forename: Keith
authors.initials: K
authors.lastname: Baronian
authors.forename: Gerd
authors.initials: G
authors.lastname: Gellissen
authors.forename: Gotthard
authors.initials: G
authors.lastname: Kunze
mesh_terms: D015374:Biosensing Techniques; D047628:Estrogen Receptor alpha / Q000235:genetics; D004967:Estrogens / Q000032:analysis*; D006801:Humans; D030781:Organisms, Genetically Modified; D004718:Saccharomycetales / Q000235:genetics*
chemical_list: D047628:Estrogen Receptor alpha; D004967:Estrogens