A Cross-Metabolomic Approach Shows that Wheat Interferes with Fluorescent Pseudomonas Physiology through Its Root Metabolites.

Laura Rieusset,Gilles Comte,Florence Wisniewski-Dyé,Claire Prigent-Combaret,Marjolaine Rey,Florence Gerin

doi:10.3390/metabo11020084

Abstract

Roots contain a wide variety of secondary metabolites. Some of them are exudated in the rhizosphere, where they are able to attract and/or control a large diversity of microbial species. In return, the rhizomicrobiota can promote plant health and development. Some rhizobacteria belonging to the Pseudomonas genus are known to produce a wide diversity of secondary metabolites that can exert a biological activity on the host plant and on other soil microorganisms. Nevertheless, the impact of the host plant on the production of bioactive metabolites by Pseudomonas is still poorly understood. To characterize the impact of plants on the secondary metabolism of Pseudomonas, a cross-metabolomic approach has been developed. Five different fluorescent Pseudomonas strains were thus cultivated in the presence of a low concentration of wheat root extracts recovered from three wheat genotypes. Analysis of our metabolomic workflow revealed that the production of several Pseudomonas secondary metabolites was significantly modulated when bacteria were cultivated with root extracts, including metabolites involved in plant-beneficial properties.

Highlights

Plant roots contain a large range of metabolites, both primary and secondary [1].The metabolic content of the roots is dependent on the plant species, and on plant genotypes, as well as on biotic or abiotic interactions occurring in the rhizosphere [2,3,4]
In order to evaluate the impact of plant extracts on the expression of bacterial phytobeneficial properties, we focused our attention on bioactive secondary metabolites produced by the studied strains [14,28]
The differential production of Pseudomonas secondary metabolites reflects its physiological response to wheat root metabolites

Summary

Introduction

The metabolic content of the roots is dependent on the plant species, and on plant genotypes, as well as on biotic or abiotic interactions occurring in the rhizosphere [2,3,4]. Some of these metabolites are secreted into the surrounding soil [5,6]. Through exudation of these compounds, roots interact with a wide range of microorganisms to form the rhizosphere microbial community [7]. Some plant secondary metabolites like coumarin or benzoxazinoids can, for example, influence the composition of the root microbiome [6,8,10]

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Results

Discussion

Conclusion