Sun Chenyu, Sun Bin, Chen Lin, Zhang Meilin, Lu Pingping, Wu Mengfan, Xue Quanhong, Guo Qiao, Tang Dejian, Lai Hangxian
College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, Shaanxi, China.
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, Faculty of Life Sciences, Northwest University, Xi'an 710069, Shaanxi, China.
Cell Host Microbe. 2024 Dec 11;32(12):2148-2160.e7. doi: 10.1016/j.chom.2024.10.015. Epub 2024 Nov 18.
Root exudates can benefit plant growth and health by reshaping the rhizosphere microbiome. Whether nanoparticles biosynthesized by rhizosphere microbes play a similar role in plant microbiome manipulation remains enigmatic. Herein, we collect elemental selenium nanoparticles (SeNPs) from selenobacteria associated with maize roots. In vitro and soil assays show that the SeNPs enhanced plant performance by recruiting plant growth-promoting bacteria (e.g., Bacillus) in a dose-dependent manner. Multiomic profilings unravel a cross-kingdom-signaling cascade that mediates efficient biosynthesis of SeNPs by selenobacteria. Specifically, maize roots perceive histamine signaling from Bacillus spp., which stimulates the plant to produce p-coumarate via root exudation. The rpoS gene in selenobacteria (e.g., Pseudomonas sp. ZY71) responds to p-coumarate signaling and positively regulates the biosynthesis of SeNPs. This study demonstrates a novel mechanism for recruiting host-beneficial soil microbes by microbially synthesized nanoparticles and unlocks promising possibilities for plant microbiome manipulation.
根系分泌物可通过重塑根际微生物群来促进植物生长和健康。根际微生物生物合成的纳米颗粒在植物微生物群调控中是否发挥类似作用仍不清楚。在此，我们从与玉米根相关的硒细菌中收集了元素硒纳米颗粒（SeNPs）。体外和土壤试验表明，SeNPs通过以剂量依赖的方式招募促进植物生长的细菌（如芽孢杆菌）来增强植物性能。多组学分析揭示了一个跨界信号级联反应，该反应介导了硒细菌对SeNPs的高效生物合成。具体而言，玉米根感知来自芽孢杆菌属的组胺信号，这刺激植物通过根系分泌产生对香豆酸。硒细菌（如假单胞菌属ZY71）中的rpoS基因对香豆酸信号作出反应，并正向调节SeNPs的生物合成。本研究证明了微生物合成的纳米颗粒招募宿主有益土壤微生物的新机制，并为植物微生物群调控开辟了广阔前景。
