Biotransformation of the mycotoxin deoxynivalenol in fusarium resistant and susceptible near isogenic wheat lines

PLoS One. 2015 Mar 16;10(3):e0119656. doi: 10.1371/journal.pone.0119656. eCollection 2015.

Abstract

In this study, a total of nine different biotransformation products of the Fusarium mycotoxin deoxynivalenol (DON) formed in wheat during detoxification of the toxin are characterized by liquid chromatography-high resolution mass spectrometry (LC-HRMS). The detected metabolites suggest that DON is conjugated to endogenous metabolites via two major metabolism routes, namely 1) glucosylation (DON-3-glucoside, DON-di-hexoside, 15-acetyl-DON-3-glucoside, DON-malonylglucoside) and 2) glutathione conjugation (DON-S-glutathione, "DON-2H"-S-glutathione, DON-S-cysteinyl-glycine and DON-S-cysteine). Furthermore, conjugation of DON to a putative sugar alcohol (hexitol) was found. A molar mass balance for the cultivar 'Remus' treated with 1 mg DON revealed that under the test conditions approximately 15% of the added DON were transformed into DON-3-glucoside and another 19% were transformed to the remaining eight biotransformation products or irreversibly bound to the plant matrix. Additionally, metabolite abundance was monitored as a function of time for each DON derivative and was established for six DON treated wheat lines (1 mg/ear) differing in resistance quantitative trait loci (QTL) Fhb1 and/or Qfhs.ifa-5A. All cultivars carrying QTL Fhb1 showed similar metabolism kinetics: Formation of DON-Glc was faster, while DON-GSH production was less efficient compared to cultivars which lacked the resistance QTL Fhb1. Moreover, all wheat lines harboring Fhb1 showed significantly elevated D3G/DON abundance ratios.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biotransformation
  • Dipeptides
  • Fusarium / physiology*
  • Host-Pathogen Interactions*
  • Mycotoxins / metabolism*
  • Plant Diseases / microbiology*
  • Trichothecenes / metabolism*
  • Triticum / metabolism*
  • Triticum / microbiology*

Substances

  • Dipeptides
  • Mycotoxins
  • Trichothecenes
  • cysteinylglycine
  • deoxynivalenol

Grants and funding

The Austrian Science Fund (projects SFB Fusarium #3706-B11 and #F3702-B11), the Federal Country Lower Austria and the European Regional Development Fund (ERDF) of the European Union (Grant Number GZ WST3-T-95/001-2006) are greatly acknowledged for financial support. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.