University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal

Selected Publication:

Schweiger, W; Berthiller, F; Fischer, A; Erhart, C; Bicker, W; Shams, M; Schuhmacher, R; Krska, R; Wiesenberger, G; Mitterbauer, R; Glatt, H; Adam, G.
(2008): Formation of zearalenone-4-sulfate by yeast cells expressing sulfotransferase genes

Plants and animals arc able to inactivate mycotoxins and other xenobiotics by sulfo-conjugation as part of phase II detoxification. ZON-4-sulfate (Z4S) is produced by Arabidopsis thaliana upon treatment with zearalenone. Z4S is most likely also a metabolite formed in animals. At present it is unknown which enzymes are involved and whether allelic differences in human or animal sulfotransferase (SULT) genes are relevant for the ability to defoxify ZON to Z4S. SULTs are encoded by large gene families in plants and animals, but are absent from the genome of bakers yeast. We therefore attempt to utilize Saccharomyces cerevisiae for functional testing of SULTs by heterologous expression. Transformants containing expression vectors, where the SULT reading frames were cloned behind the strong ADHI promoter, produced only minor amounts of Z4S upon treatment with ZON, probably due to low levels of the sulfotransferase proteins and possibly due to depletion of the SULT co-substrate 3-phosphoadenosine 5'-phosphosulfate (PAPS, activated sulfate). To improve the expression of the SULTs we have constructed N-terminal GST fusions. To increase the availability of the co-substrate PAPS we have overexpressed the human high affinity PAPS-synthase 1. Preliminary results with human SULTIE1 showed that after treatment with ZON 3.4-fold higher levels of Z4S were found in the Culture medium, when the cells expressed the GST-SULT fusion compared to SULT, and 1.7-fold higher levels, when the human PAPS-synthase was combined with SULT.
Authors BOKU Wien:
Adam Gerhard
Berthiller Franz
Krska Rudolf
Schuhmacher Rainer
Schweiger Wolfgang
Shams Mehrdad
Wiesenberger Gerlinde

Find related publications in this database (Keywords)

© BOKU Wien Imprint