@article{6f8ef09e641e467abef2f2ca68f4852a,
title = "A sesquiterpene synthase from the endophytic fungus Serendipita indica catalyzes formation of viridiflorol",
abstract = "Interactions between plant-associated fungi and their hosts are characterized by a contin-uous crosstalk of chemical molecules. Specialized metabolites are often produced during these associations and play important roles in the symbiosis between the plant and the fungus, as well as in the establishment of additional interactions between the symbionts and other organisms present in the niche. Serendipita indica, a root endophytic fungus from the phylum Basidiomycota, is able to colonize a wide range of plant species, conferring many benefits to its hosts. The genome of S. indica possesses only few genes predicted to be involved in specialized metabolite biosynthesis, including a putative terpenoid synthase gene (SiTPS). In our experimental setup, SiTPS expression was up-regulated when the fungus colonized tomato roots compared to its expression in fungal biomass growing on synthetic medium. Heterologous expression of SiTPS in Escherichia coli showed that the produced protein catalyzes the synthesis of a few sesquiterpenoids, with the alcohol viridiflorol being the main product. To investigate the role of SiTPS in the plant-endophyte interaction, an SiTPS-over-expressing mutant line was created and assessed for its ability to colonize tomato roots. Although overexpression of SiTPS did not lead to improved fungal colonization ability, an in vitro growth-inhibition assay showed that viridiflorol has antifungal properties. Addition of viridiflorol to the culture medium inhibited the germination of spores from a phytopathogenic fungus, indicat-ing that SiTPS and its products could provide S. indica with a competitive advantage over other plant-associated fungi during root colonization.",
keywords = "Antifungal, Basidiomycota, Endophyte, Piriformospora indica, Sesquiterpenoid, Terpene synthase, Viridiflorol",
author = "Fani Ntana and Bhat, {Wajid W.} and Johnson, {Sean R.} and J{\o}rgensen, {Hans J.L.} and Collinge, {David B.} and Birgit Jensen and Bj{\"o}rn Hamberger",
note = "Funding Information: Author Contributions: Conceptualization, F.N. and B.H.; methodology, F.N., B.H. and W.W.B.; software, S.R.J.; validation, formal analysis, investigation, F.N., W.W.B. and S.R.J.; resources, B.H. and D.B.C.; writing—original draft preparation, writing—review and editing, all authors; visualization, F.N., W.W.B. and B.J; supervision, B.H., D.B.C., H.J.L.J. and B.J.; funding acquisition, B.H., and D.B.C. All authors have read and agreed to the published version of the manuscript Funding: This work was supported by the Michigan State University Strategic Partnership Grant program (“Evolutionary-Driven Genome Mining of Plant Biosynthetic Pathways” and “Plant-inspired Chemical Diversity”, B.H.). B.H. gratefully acknowledges the U.S. Department of Energy-Great Lakes Bioenergy Research Center Cooperative Agreement DE-SC0018409, start-up funding from the Department of Molecular Biology and Biochemistry and support by the USDA National Institute of Food and Agriculture, HATCH project MICL02454. B.H. is in part supported by the National Science Foundation under Grant Number 1737898. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. This project has also received funding from the European Union{\textquoteright}s Horizon 2020 research and innovation programme under the Marie Sk{\l}odowska-Curie grant agreement No. 676480. This material reflects only the authors{\textquoteright} view and the Research Executive Agency is not responsible for any use that may be made of the information it contains. Funding Information: This work was supported by the Michigan State University Strategic Partnership Grant program (?Evolutionary-Driven Genome Mining of Plant Biosynthetic Pathways? and ?Plant-in-spired Chemical Diversity?, B.H.). B.H. gratefully acknowledges the U.S. Department of Energy-Great Lakes Bioenergy Research Center Cooperative Agreement DE-SC0018409, start-up funding from the Department of Molecular Biology and Biochemistry and support by the USDA National Institute of Food and Agriculture, HATCH project MICL02454. B.H. is in part supported by the National Science Foundation under Grant Number 1737898. Any opinions, findings, and conclu-sions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. This project has also received funding from the European Union?s Horizon 2020 research and innovation programme under the Marie Sk?odowska-Curie grant agreement No. 676480. This material reflects only the authors? view and the Research Executive Agency is not responsible for any use that may be made of the information it contains. We would like to thank Professor Philipp Franken (Friedrich-Schiller Univer-sity, Germany) for providing the Serendipita indica DSM 11827 isolate, Professor Frank Takken (University of Amsterdam, the Netherlands) for the Solanum lycopersicum cv. Moneymaker seeds, as well as Professor Alga Zuccaro, Dr. Stephan Wawra and Dr. Heidi Widmer (University of Co-logne, Germany) for kindly providing the K167 vector and advice on the S. indica transformation procedure. Also thanks to the facilities at Michigan State University, including the Mass Spectrom-etry and Metabolomics Core. Publisher Copyright: {\textcopyright} 2021 by the authors. Licensee MDPI, Basel, Switzerland.",
year = "2021",
doi = "10.3390/biom11060898",
language = "English",
volume = "11",
journal = "Biomolecules",
issn = "2218-273X",
publisher = "MDPI",
number = "6",
}