Chemical Ecogenomics-Guided Discovery of Phytotoxic α-Pyrones from the Fungal Wheat Pathogen Parastagonospora nodorum

Abstract

A biosynthetic gene cluster that is significantly upregulated in the fungal wheat pathogen Parastagonospora nodorum during plant infection was reconstructed heterologously in Aspergillus nidulans. This led to the discovery of five new α-pyrone polyketides, alternapyrones B-F (2-6). Compounds 5 and 6, which contain a highly substituted dihydrofuran, exhibited phytotoxicity on wheat seed germination. It is demonstrated that only three enzymes, one highly reducing polyketide synthase and two multifunctional P450 oxygenases, are needed to synthesize the structurally complex products.

Heterologous biosynthesis of elsinochrome A sheds light on the formation of the photosensitive perylenequinone system

“…The system was expanded to two other auxotrophic markers, riboB (pYFAC-CH3) and pyroA (pYFAC-CH4), respectively. Together, the tripartite YFAC system is capable of inducible expression of up to 12 genes and has been used recently for genome mining of novel phytotoxic α-pyrones from P. nodorum 23…”

Bipolenins K–N: New sesquiterpenoids from the fungal plant pathogen Bipolaris sorokiniana

“…The phytotoxicity assays on wheat leaves and seeds were carried out as previously reported [37]. Briefly, the leaves of 17-days-old wheat seedlings in 10 cm planting pots were grown at 20 °C under a 16 h/8 h light/dark cycle regime.…”

Nonproteinaceous effectors: the terra incognita of plant–fungal interactions

“…Some of these approaches were termed ‘chemical ecogenomics’ by Chooi & Solomon (). Applying this method to Staganospora nodorum was successful in identifying α‐pyrones that inhibited wheat seed germination (Li et al ., ).…”