Perez-Gonzalez Gabriel, Sebestyen Dana, Petit Elsa, Jellison Jody, Mugnai Laura, Gelhaye Eric, Lee Norman, Farine Sibylle, Bertsch Christophe, Goodell Barry
Department of Microbiology, University of Massachusetts, Amherst, MA, United States.
Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA, United States.
Front Plant Sci. 2022 Jul 4;13:921961. doi: 10.3389/fpls.2022.921961. eCollection 2022.
Eutypa dieback and Esca complex are fungal diseases of grape that cause large economic losses in vineyards. These diseases require, or are enhanced by, fungal consortia growth which leads to the deterioration of the wood tissue in the grapevine trunk; however, pathogenesis and the underlying mechanisms involved in the woody tissue degradation are not understood. We examined the role that the consortia fungal metabolome have in generating oxygen radicals that could potentially play a role in trunk decay and pathogenesis. Unique metabolites were isolated from the consortia fungi with some metabolites preferentially reducing iron whereas others were involved in redox cycling to generate hydrogen peroxide. Metabolite suites with different functions were produced when fungi were grown separately vs. when grown in consortia. Chelator-mediated Fenton (CMF) chemistry promoted by metabolites from these fungi allowed for the generation of highly reactive hydroxyl radicals. We hypothesize that this mechanism may be involved in pathogenicity in grapevine tissue as a causal mechanism associated with trunk wood deterioration/necrosis in these two diseases of grape.
葡萄藤猝死病和埃斯卡综合症是葡萄的真菌病害，会给葡萄园造成巨大经济损失。这些病害需要真菌群落生长，或者真菌群落生长会加剧病害，这会导致葡萄树干木质组织退化；然而，木质组织降解所涉及的发病机制和潜在机制尚不清楚。我们研究了真菌群落代谢组在产生氧自由基方面所起的作用，这些氧自由基可能在树干腐烂和发病过程中发挥作用。从真菌群落中分离出了独特的代谢物，有些代谢物优先还原铁，而其他代谢物则参与氧化还原循环以产生过氧化氢。真菌单独生长与群落生长时会产生具有不同功能的代谢物组。这些真菌产生的代谢物促进的螯合剂介导芬顿（CMF）化学反应能够产生高活性羟基自由基。我们推测，这种机制可能与葡萄组织的致病性有关，是这两种葡萄病害中与树干木质部退化/坏死相关的一种致病机制。
