Universität zu Köln

Getzke, Felix ORCID: 0000-0002-7694-1902 (2022). Versatile functions of bacterial exometabolites in microbe- microbe and plant-microbe interactions. PhD thesis, Universität zu Köln.

PDF Dissertation - Felix Getzke_for publication.pdf Download (15MB)

Abstract

In nature, roots of Arabidopsis thaliana are colonized by taxonomically diverse, soil-derived communities mainly comprising bacteria and fungi. Collectively, these root-associated microbial communities are termed root microbiota and are characterized by reduced microbial diversity and robust community structures compared to soil-associated communities. While plant secondary metabolism and the innate immune system have been demonstrated to influence root microbiota establishment, the role of microbial interactions and the underlying mechanisms for root microbiota establishment remain largely elusive. Using combinatorial approaches of binary interaction screens, forward and reverse genetics, targeted metabolomics, microbiota reconstitution, and marker gene amplicon sequencing-based community profiling, we provide genetic evidence for a root-specific functioning of bacterial secreted exometabolites in root microbiota establishment. We further demonstrate that a sole antimicrobial bacterial secondary metabolite is sufficient to cause plant disease under hyperosmotic conditions, illustrating the versatile role of these inhibitory molecules for microbe-microbe and host microbe interactions. Finally, we provide evidence for the modulation of microbial interactions by the availability of easily accessible carbon, collectively, suggesting that root exudates drive microbial interactions in the rhizosphere, likely contributing to the observed reduction of microbial diversity across the soil-root continuum. Collectively, our data demonstrate the relevance of bacterial exometabolites for root microbiota establishment and host health.

Item Type:	Thesis (PhD thesis)
Translated title:	Title Language UNSPECIFIED German
Creators:	Creators Email ORCID ORCID Put Code Getzke, Felix felix.getzke@gmail.com orcid.org/0000-0002-7694-1902 UNSPECIFIED
URN:	urn:nbn:de:hbz:38-752154
Date:	2022
Language:	English
Faculty:	Faculty of Mathematics and Natural Sciences
Divisions:	Faculty of Mathematics and Natural Sciences > Department of Biology > Botanical Institute
Subjects:	Life sciences
Uncontrolled Keywords:	Keywords Language bacterial exometabolites English microbe-microbe interactions English microbe-plant interactions English
Date of oral exam:	27 February 2023
Referee:	Name Academic Title Schulze-Lefert, Paul Prof. Dr. Kopriva, Stanislav Prof. Dr.
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/75215