Institute for Microbiology, Plant Microbiosis Group, Friedrich Schiller University Jena, Jena, Germany.
Schülerforschungszentrum Berchtesgaden, Didactics of Life Science, Technical University of Munich, Munich, Germany.
Nat Commun. 2024 Oct 1;15(1):8496. doi: 10.1038/s41467-024-52679-7.
Host defenses can have broader ecological roles, but how they shape natural microbiome recruitment is poorly understood. Aliphatic glucosinolates (GLSs) are secondary defense metabolites in Brassicaceae plant leaves. Their genetically defined structure shapes interactions with pests in Arabidopsis thaliana leaves, and here we find that it also shapes bacterial recruitment. In model genotype Col-0, GLSs (mostly 4-methylsulfinylbutyl-GLS) have no clear effect on natural leaf bacterial recruitment. In a genotype from a wild population, however, GLSs (mostly allyl-GLS) enrich specific taxa, mostly Comamonadaceae and Oxalobacteraceae. Consistently, Comamonadaceae are also enriched in wild A. thaliana, and Oxalobacteraceae are enriched from wild plants on allyl-GLS as carbon source, but not on 4-methylsulfinylbutyl-GLS. Recruitment differences between GLS structures most likely arise from bacterial myrosinase specificity. Community recruitment is then defined by metabolic cross-feeding among bacteria. The link of genetically defined metabolites to recruitment could lead to new strategies to shape plant microbiome balance.
宿主防御可以具有更广泛的生态作用，但它们如何塑造自然微生物组的招募还知之甚少。脂肪族硫代葡萄糖苷（GLS）是十字花科植物叶片中的次生防御代谢物。它们的遗传定义结构塑造了与拟南芥叶片中害虫的相互作用，在这里我们发现它也塑造了细菌的招募。在模型基因型 Col-0 中，GLS（主要是 4-甲基亚磺酰基丁基-GLS）对自然叶片细菌的招募没有明显影响。然而，在来自野生种群的基因型中，GLS（主要是烯丙基-GLS）富集了特定的分类群，主要是根瘤菌科和草酸杆菌科。一致地，根瘤菌科也在野生拟南芥中富集，草酸杆菌科从含有烯丙基-GLS 的野生植物中富集作为碳源，但不能从含有 4-甲基亚磺酰基丁基-GLS 的植物中富集。不同 GLS 结构之间的招募差异很可能源于细菌糜蛋白酶的特异性。群落的招募随后由细菌之间的代谢交叉喂养来定义。遗传定义代谢物与招募的联系可能会导致塑造植物微生物组平衡的新策略。
