The research group Geomicrobiology within the Department of Microorganisms of the Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures GmbH
PhD student position on the Ecology and annual dynamics of Thaumarchaeota-driven freshwater nitrification
Nitrification is an essential step in the nitrogen cycle. Ammonia-oxidizing Thaumarchaeota (AOA) sustain large populations in deep oligotrophic lakes (up to 40%) and provide an important ecosystem service for safe drinking water supply. This project aims to elucidate environmental controls of freshwater AOA populations and the annual dynamics of the ecosystem service they provide. AOA-driven nitrification and dark CO2-fixation rates will be investigated using stable isotope labeling techniques coupled to GC-IRMS, EA-IRMS and nano-SIMS measurements. In parallel, metagenomics and electron/fluorescent microscopy of FACS-sorted AOA cells will be used to explore the rate of viral infection and identity of infecting viruses. An ultimate goal is to isolate AOA and their viruses into pure culture.