2020 Volume 70 Issue 2 Pages 67-74
Food and environmental exposure to trichothecenes, a group of mycotoxins produced by filamentous fungi such as Fusarium, Trichothecium, Trichoderma, and Myrothecium, threatens the health of humans and livestock. The toxins are conventionally classified into types A through D based on their characteristic chemical structures (e.g., the presence of C-8 ketone, 7,8-epoxide, or macrocyclic ring between C-4 and C-15). However, from the viewpoint of biosynthesis, it is more reasonable to classify them into two groups, C-3 unoxygenated d-type trichothecenes and C-3 oxygenated t-type trichothecenes, which are produced by the cyclization of isotrichodiol and isotrichotriol, respectively. Using molecular genetic approaches, we characterized the biosynthetic enzymes of several trichothecene-producing fungi and identified many natural and unnatural trichothecenes. Based on our achievements, an MS/MS library comprising various trichothecene intermediates is being constructed. We believe that in the near future, our MS/MS library will be useful for detecting the emergence of novel trichothecenes.
