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bioRxiv · 10.1101/2023.05.03.538910

Identification of the conserved iol gene cluster involved in rhizosphere competence in Pseudomonas

Sanchez-Gil, J. J.·Poppeliers, S. W. M.·Vacheron, J. J.·Zhang, H.·Odijk, B. S.·Keel, C.·de Jonge, R.
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Abstract

The Pseudomonas genus has shown great potential as a sustainable solution to support agriculture through its plant-growth promoting and biocontrol activities. However, their efficacy as bioinoculants is limited by unpredictable colonization in natural conditions. Our study identifies the iol locus, a gene cluster in Pseudomonas involved in inositol catabolism, as a feature enriched among superior root colonizers in natural soil. Further characterization revealed that the iol locus increases competitiveness by inducing swimming motility and fluorescent siderophore production in response to inositol, a plant-derived compound. Public data analyses indicate that the iol locus is broadly conserved in the Pseudomonas genus and linked to diverse host-microbe interactions. Our findings suggest the iol locus as a potential target for developing more effective bioinoculants, given its conservation and association with diverse host-microbe interactions.

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Sanchez-Gil, J. J., Poppeliers, S. W. M., Vacheron, J. J., Zhang, H., Odijk, B. S., Keel, C., de Jonge, R.. 2023-05-03. Identification of the conserved iol gene cluster involved in rhizosphere competence in Pseudomonas. https://doi.org/10.1101/2023.05.03.538910

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