Fungi associated with Norway spruce and its bark beetles detoxify spruce defense compounds by conjugation to α-ribose.

Fungi associated with Norway spruce and bark beetles detoxify defense compounds by converting stilbene aglucones into α-ribofuranosylated derivatives, reducing toxicity and enhancing growth.

• Why it matters: Conifers produce high levels of antifungal phenolics in their tissues, yet fungi can still colonize these defenses, highlighting a gap in understanding how they overcome plant resistance mechanisms.
• What they did: Using untargeted metabolomics, structural analysis, and biochemical assays, the study examined how fungi hydrolyze stilbene glucosides and convert aglucones into α-ribofuranosides, focusing on two basidiomycetes.
• The result: Conversion to α-ribofuranosides significantly diminishes antifungal activity and stabilizes the compounds, enabling fungi to bypass defenses and support bark beetle colonization, facilitating conifer attack.