Surfactin Stimulated by Pectin Molecular Patterns and Root Exudates Acts as a Key Driver of the Bacillus-Plant Mutualistic Interaction

mBio

Yannick Lara¹  Heba M. M. Ibrahim²  Barbara de Coninck²  Edwin de Pauw³  Victoria Osorio³  Farah Boubsi⁴  Patricio Luzuriaga⁴  Anthony Arguelles Arias⁴  Thibault Meyer⁴  Jelena Pršić⁴  Aurélien Legras⁴  Marc Ongena⁴  Philippe Jacques⁴  Grégory Hoff⁴  Sébastien Steels⁴  Laurent Franzil⁴  Magali Deleu⁵  Estelle Deboever⁵  Emmanuel Petit⁶  Michelle Lequart-Pillon⁶  Catherine Rayon⁶  Olivier Van Wuytswinkel⁶ 

[1] Astrobiology, UR-ASTROBIOLOGY, Geology Department, University of Liège, Liège, Belgium;Division of Plant Biotechnics, Department of Biosystems, Faculty of Bioscience Engineering, KU Leuven, Leuven, Belgium;Mass Spectrometry Laboratory, MolSys Research Unit, Department of Chemistry, University of Liège, Liège, Belgium;Microbial Processes and Interactions, TERRA Teaching and Research Center, BioEcoAgro, Joint Research Unit/UMR transfrontalière 1158, University of Liège‐Gembloux Agro‐Bio Tech, Gembloux, Belgium;Molecular Biophysics at Interfaces Laboratory, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium;Unité Biologie des Plantes et Innovation, BioEcoAgro, Joint Research Unit/UMR Transfrontalière 1158, Université de Picardie Jules Verne, UFR des Sciences, Amiens, France;

关键词: lipopeptides;    plant cell wall polymers;    plant immunity;    molecular crosstalk;    plant-microbe interactions;   

DOI  :  10.1128/mBio.01774-21

来源: DOAJ

【 摘 要 】

ABSTRACT Bacillus velezensis is considered as a model species belonging to the so-called Bacillus subtilis complex that evolved typically to dwell in the soil rhizosphere niche and establish an intimate association with plant roots. This bacterium provides protection to its natural host against diseases and represents one of the most promising biocontrol agents. However, the molecular basis of the cross talk that this bacterium establishes with its natural host has been poorly investigated. We show here that these plant-associated bacteria have evolved a polymer-sensing system to perceive their host and that, in response, they increase the production of the surfactin-type lipopeptide. Furthermore, we demonstrate that surfactin synthesis is favored upon growth on root exudates and that this lipopeptide is a key component used by the bacterium to optimize biofilm formation, motility, and early root colonization. In this specific nutritional context, the bacterium also modulates qualitatively the pattern of surfactin homologues coproduced in planta and forms mainly variants that are the most active at triggering plant immunity. Surfactin represents a shared good as it reinforces the defensive capacity of the host. IMPORTANCE Within the plant-associated microbiome, some bacterial species are of particular interest due to the disease protective effect they provide via direct pathogen suppression and/or stimulation of host immunity. While these biocontrol mechanisms are quite well characterized, we still poorly understand the molecular basis of the cross talk these beneficial bacteria initiate with their host. Here, we show that the model species Bacillus velezensis stimulates the production of the surfactin lipopeptide upon sensing pectin as a cell surface molecular pattern and upon feeding on root exudates. Surfactin favors bacterial rhizosphere fitness on one hand and primes the plant immune system on the other hand. Our data therefore illustrate how both partners use this multifunctional compound as a unique shared good to sustain a mutualistic interaction.

【 授权许可】

Unknown