Coordinated bacterial and plant sulfur metabolism in Enterobacter sp. SA187–induced plant salt stress tolerance

Cristina Andres-Barrao, Hanin S. Alzubaidy, Rewaa S. Jalal, Kiruthiga Mariappan, Axel de Zélicourt, Ameerah Bokhari, Olga Artyukh, Khairiah Mubarak Saleem Alwutayd, Anamika Rawat, Kirti Shekhawat, Marília Almeida-Trapp, Maged Saad, Heribert Hirt

Research output: Contribution to journalArticlepeer-review

42 Scopus citations


Enterobacter sp. SA187 is a root endophytic bacterium that maintains growth and yield of plants under abiotic stress conditions. In this work, we compared the metabolic wirings of Arabidopsis and SA187 in the free-living and endophytic interaction states. The interaction of SA187 with Arabidopsis induced massive changes in bacterial gene expression for chemotaxis, flagellar biosynthesis, quorum sensing, and biofilm formation. Besides modification of the bacterial carbon and energy metabolism, various nutrient and metabolite transporters and the entire sulfur pathway were up-regulated. Under salt stress, Arabidopsis resembled plants under sulfate starvation but not when colonized by SA187, which reprogramed the sulfur regulon of Arabidopsis. In accordance, salt hypersensitivity of multiple Arabidopsis sulfur metabolism mutants was partially or completely rescued by SA187 as much as by the addition of sulfate, L-cysteine, or L-methionine. Many components of the sulfur metabolism that are localized in the chloroplast were partially rescued by SA187. Finally, salt-induced accumulation of reactive oxygen species as well as the hypersensitivity of LSU mutants were suppressed by SA187. LSUs encode a central regulator linking sulfur metabolism to chloroplast superoxide dismutase activity. The coordinated regulation of the sulfur metabolic pathways in both the beneficial microorganism and the host plant is required for salt stress tolerance in Arabidopsis and might be a common mechanism utilized by different beneficial microbes to mitigate the harmful effects of different abiotic stresses on plants.
Original languageEnglish (US)
Pages (from-to)e2107417118
JournalProceedings of the National Academy of Sciences
Issue number46
StatePublished - Nov 12 2021

Bibliographical note

KAUST Repository Item: Exported on 2021-11-15
Acknowledgements: This work is a part of the DARWIN21 project ( for exploration of desert microbes. We thank Stan Kopriva (Univeristy of Cologne) for providing sultr1;2, apk1, apk2, and apr2 seeds, Herve Vaucheret (French National Research Institute for Agriculture, Food and Environment (INRAE)-Versailles) for providing fry1-1 and fry1-4 seeds, Ruediger Hell (University of Heidelberg) for providing sir1-1 seeds, Pascal Falter-Braun (Ludwig Maximilian University of Munich) for providing amiRLSUa-c seeds, and all members of the H.H. laboratory, including Abdul Aziz

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Coordinated bacterial and plant sulfur metabolism in Enterobacter sp. SA187–induced plant salt stress tolerance'. Together they form a unique fingerprint.

Cite this