Birgit Arndt

Ms. Birgit Arndt


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 April 2017 in Toxins
Verified
Journal Article
Open access
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Slavica JanevskaSlavica Janevska
Slavica Janevska
BABirgit Arndt
Birgit Arndt
LBLeonie Baumann
Leonie Baumann
LALisa Helene Apken
Lisa Helene Apken
LMLucas Maciel Mauriz Marques
Lucas Maciel Mauriz Marques
BTBettina Tudzynski
Bettina Tudzynski
The PKS-NRPS-derived tetramic acid equisetin and its N-desmethyl derivative trichosetin exhibit remarkable biological activities against a variety of organisms, including plants and bacteria, e.g., Staphylococcus aureus. The equisetin biosynthetic gene cluster was first described in Fusarium heterosporum, a species distantly related to the notorious rice pathogen Fusarium fujikuroi. Here we present the activation and characterization of a homologous, but silent, gene cluster in F. fujikuroi. Bioinformatic analysis revealed that this cluster does not contain the equisetin N-methyltransferase gene eqxD and consequently, trichosetin was isolated as final product. The adaption of the inducible, tetracycline-dependent Tet-on promoter system from Aspergillus niger achieved a controlled overproduction of this toxic metabolite and a functional characterization of each cluster gene in F. fujikuroi. Overexpression of one of the two cluster-specific transcription factor (TF) genes, TF22, led to an activation of the three biosynthetic cluster genes, including the PKS-NRPS key gene. In contrast, overexpression of TF23, encoding a second Zn(II)2Cys6 TF, did not activate adjacent cluster genes. Instead, TF23 was induced by the final product trichosetin and was required for expression of the transporter-encoding gene MFS-T. TF23 and MFS-T likely act in consort and contribute to detoxification of trichosetin and therefore, self-protection of the producing fungus.