Peroxidase 4‑Based\nEnzymatic Synthesis of Stilbene\nOligomers in Methyl\nJasmonate-Elicited Grapevine Cell Suspensions

Stilbenes are specialized metabolites that are particularly\nabundant\nin Vitis species. Although the biosynthetic\npathways of stilbenes have been well-characterized, the role of specific\nperoxidases in stilbene oligomerization remains to be investigated.\nIn this study, we used grapevine cell cultures to characterize the\nfunctional role of Vitis vinifera peroxidase\n4 (VvPRX4) in the production of resveratrol oligomers after elicitation\nwith methyl jasmonate (MeJA). We showed that MeJA triggers the accumulation\nof <i>t</i>-resveratrol, resveratrol dimers, and predicted\nresveratrol trimers in culture medium. This accumulation was correlated\nwith upregulation of the <i>PRX4</i> gene in grapevine cells.\nUsing bacterial crude extracts containing VvPRX4, we demonstrated\nthat VvPRX4 converts <i>t</i>-resveratrol into dimers, <i>t</i>-ε-viniferin into tetramers, and both combined substrates\ninto resveratrol trimers. Additionally, VvPRX4 mediates the formation\nof glycosylated dimers using <i>t</i>-piceid and <i>t</i>-resveratrol as substrates. These results highlight the\nfunctional role of VvPRX4 in stilbene oligomerization in MeJA-elicited\ngrapevine cell cultures.