Department of Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
Philipps-University Marburg, Center for Synthetic Microbiology (SYNMIKRO) and Department of Chemistry, Marburg, Germany.
Nature. 2019 Jan;565(7741):650-653. doi: 10.1038/s41586-018-0857-9. Epub 2019 Jan 16.
Fungi-induced plant diseases affect global food security and plant ecology. The biotrophic fungus Ustilago maydis causes smut disease in maize (Zea mays) plants by secreting numerous virulence effectors that reprogram plant metabolism and immune responses. The secreted fungal chorismate mutase Cmu1 presumably affects biosynthesis of the plant immune signal salicylic acid by channelling chorismate into the phenylpropanoid pathway. Here we show that one of the 20 maize-encoded kiwellins (ZmKWL1) specifically blocks the catalytic activity of Cmu1. ZmKWL1 hinders substrate access to the active site of Cmu1 through intimate interactions involving structural features that are specific to fungal Cmu1 orthologues. Phylogenetic analysis suggests that plant kiwellins have a versatile scaffold that can specifically counteract pathogen effectors such as Cmu1. We reveal the biological activity of a member of the kiwellin family, a widely conserved group of proteins that have previously been recognized only as important human allergens.
真菌引起的植物病害影响全球粮食安全和植物生态。生物营养型真菌玉米黑粉菌通过分泌大量毒力效应子来 reprogram 植物代谢和免疫反应，从而引起玉米（Zea mays）植物的黑粉病。分泌的真菌分支酸变位酶 Cmu1 可能通过将分支酸导入苯丙烷途径来影响植物免疫信号水杨酸的生物合成。在这里，我们表明，20 个玉米编码的 kiwellin 之一（ZmKWL1）特异性地阻断 Cmu1 的催化活性。ZmKWL1 通过涉及真菌 Cmu1 同源物特有的结构特征的密切相互作用，阻碍底物进入 Cmu1 的活性位点。系统发育分析表明，植物 kiwellin 具有多功能支架，可以特异性地对抗 Cmu1 等病原体效应子。我们揭示了 kiwellin 家族成员的生物学活性，kiwellin 家族是一个广泛保守的蛋白质家族，以前仅被认为是重要的人类过敏原。
