Identification of N,N',N″-triacetylfusarinine C as a key metabolite for root rot disease virulence in American ginseng

Jacob P Walsh; Natasha DesRochers; Justin B Renaud; Keith A Seifert; Ken K-C Yeung; Mark W Sumarah

doi:10.1016/j.jgr.2019.08.008

Identification of N,N',N″-triacetylfusarinine C as a key metabolite for root rot disease virulence in American ginseng

J Ginseng Res. 2021 Jan;45(1):156-162. doi: 10.1016/j.jgr.2019.08.008. Epub 2019 Sep 13.

Authors

Jacob P Walsh^{1

2}, Natasha DesRochers^{1

2}, Justin B Renaud¹, Keith A Seifert³, Ken K-C Yeung^{2

4}, Mark W Sumarah^{1

2}

Affiliations

¹ London Research and Development Center, Agriculture and Agri-Food Canada, London, ON, N5V 4T3, Canada.
² Department of Chemistry, University of Western Ontario, London, ON, N6A 5B7, Canada.
³ Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, 960 Carling Ave., Ottawa, ON, K1A 0C6, Canada.
⁴ Department of Biochemistry, University of Western Ontario, London, ON, N6A 5C1, Canada.

Abstract

Background: It is estimated that 20-30% of ginseng crops in Canada are lost to root rot each harvest. This disease is commonly caused by fungal infection with Ilyonectria, previously known as Cylindrocarpon. Previous reports have linked the virulence of fungal disease to the production of siderophores, a class of small-molecule iron chelators. However, these siderophores have not been identified in Ilyonectria.

Methods: High-resolution LC-MS/MS was used to screen Ilyonectria and Cylindrocarpon strain extracts for secondary metabolite production. These strains were also tested for their ability to cause root rot in American ginseng and categorized as virulent or avirulent. The differences in detected metabolites between the virulent and avirulent strains were compared with a focus on siderophores.

Results: For the first time, a siderophore N,N',N″-triacetylfusarinine C (TAFC) has been identified in Ilyonectria, and it appears to be linked to disease virulence. Siderophore production was suppressed as the concentration of iron increased, which is in agreement with previous reports.

Conclusion: The identification of the siderophore produced by Ilyonectria gives us further insight into the root rot disease that heavily affects ginseng crop yields. This research identifies a molecular pathway previously unknown for ginseng root rot and could lead to new disease treatment options.

Keywords: Ilyonectria mors-panacis; Panax quinquefolius; Root rot; Siderophore.