Project information

Please find below short project information texts for the positions announced in our May 2023 call. We hope these descriptions pique your interest in our research topics!

 

Survival and resuscitation mechanisms of desert soil bacteria

Microorganisms in drylands have to endure long periods of drought, interrupted by unpredictable and very short periods of rain. Dormancy - an inactive state or a state of reduced metabolic activity - has long been regarded as a prerequisite for desert soil microorganisms to survive such drought periods. However, as dormancy cannot be sustained indefinitely, phases of resuscitation must also play an important role for long-term survival of desert soil microorganisms and thus for maintaining microbial diversity in one of the harshest environments on the planet.
In this project, we are investigating the desiccation survival mechanisms of soil microorganisms and the molecular mechanisms of resuscitation. This will be achieved by applying genome-resolved metatranscriptomics of desert soil microbial communities, building upon knowledge gained by our recent metagenomic investigation of biological soil crusts from the Negev Desert, Israel. In situ community transcription patterns will be combined with single-cell activity assays, employing a recently developed heavy water-NanoSIMS assay to detect anabolically active cells, and process measurements.

 

Identification of tire wear additives in plant agriculture

Soil is one of the major receptors of tire wear particles (TWP), where they can release ecotoxicological relevant substances. Various processes including biotic and abiotic aging, aggregation, or fragmentation influence the properties of TWPs and affect the leaching behavior. The fate of TWP and tire-derived contaminants in agricultural environments remain poorly understood and closing this knowledge gap is a key aim of this project. 

 

How to detect biodegradable plastics in compost and improve compostability?

Biodegradable plastics can be part of a solution to the global plastic pollution problem. One example are materials that are completely biodegraded during biowaste composting processes. Harmonized and widely accepted methods for plastic analyses as an essential part of biodegradation studies are needed. We are looking for a highly enthusiastic Ph.D. student (m/f/x) with an interest in developing such methods and in assessing the fate of microplastic particles during the (bio)degradation of plastics in compost.

 

Remediation of forever chemicals: PFAS in groundwater

PFAS, known as "forever chemicals" due to their difficult degradation, have been associated with adverse health effects on humans and wildlife. PFAS are extremely stable because they are made up of a chain of carbon and fluorine atoms bonded together, and the carbon-fluorine bond is one of the strongest chemical bonds. PFAS remediation is extremely difficult and involves extreme heat, sorbents which need to be recycled, and other techniques, all of which can be costly, inefficient and create secondary pollutants. This projects aims to work on innovative PFAS remediation in groundwater. We are looking for a highly enthusiastic Ph.D. student (m/f/x) with an interest in developing such techniques and a solid background in chemistry. 

 

Identification of host intrinsic factors that shape the sponge microbiome

Sponges (phylum Porifera) are amongst the most basal metazoans. These sessile filter feeders are important constituents of benthic ecosystems, as they can occupy up to 80% of the available substrate, provide habitat for a wide range of infaunal species, be a vital trophic link between the benthos and the pelagic realm through their remarkable filtration capacity, and mediate biogeochemical fluxes through the uptake of organic matter and the recycling of nutrients. In coral reef ecosystems, for example, sponges are part of a highly efficient recycling pathway (the sponge loop), as sponges take up dissolved organic matter from oligotrophic waters and convert it into cellular detritus that becomes food for higher trophic levels. Furthermore, sponges are known for their ubiquitous production of bioactive metabolites with a broad range of biochemical and biomedical applications. Besides their evolutionary, ecological, and biotechnological importance, sponges are also prominent examples of highly complex microbial symbioses. The microbial consortium of sponges can make up to 35% of the holobiont’s biomass, is known for its remarkable diversity, and has a fundamental role in the sponge’s physiology and ecology. Despite the constant exposure to seawater microbes, sponges can maintain a highly stable and species-specific microbial community.
The main aim of the Ph.D. project is to identify host intrinsic factors (i.e., host morphology, secondary metabolites production, host phylogeny) that drive microbiome variations among distinct sponge species and to visualize the host-symbiont landscape in the tissue of marine sponges at a single cell level.