Modulation of the endophytic strain Kosakonia radicincitans UYSO10 proteome by sugarcane root exudates

Plant-associated microbiotas play a key role in plant health, growth, and stresses resilience. One main component of the plant microbiota is the endophytic bacterial communities, which live inside the internal tissues. The principal sources of this microbiota are the seed and the soil. Particularly, soil bacteria are attracted by different signals present in plant root exudates, to colonize the rhizoplane later to infect internal tissues. Although endophytic bacteria’s colonization and infection processes are well documented, the molecular bases of the mechanisms involved are still poorly understood. Previously it was shown that endophytic strain Kosakonia radicincitans UYSO10 promotes the growth of sugarcane plants and was defined as a true endophyte. It was also demonstrated that the biological nitrogen fixation process is involved in plant growth promotion by the strain UYSO10. This work aimed to expand the knowledge about the adaptations of the diazotrophic endophytic strain UYSO10 to sugarcane root exudates, and identify possible mechanisms involved.

Two quantitative complementary proteomic techniques were used to study the response of the strain UYSO10 to sugarcane root exudates.

Roots exudates induce quantifiable changes in the strain UYSO10 bacterial proteome, including the remodeling of several pathways toward the metabolic adaptation to the nutrients available, the bacterial membrane remodeling, and changes that allow the shift from a planktonic lifestyle to biofilm formation.

Results deepen the knowledge of the bacterial adaptation to the rhizosphere environment toward root infection, and identify potential mechanisms involved in the sugarcane plant-UYSO10 strain interaction.