Project

Cultivating Asgards, eukaryotes’ closest relatives

Using targeted cultivation methods to cultivate novel members of the Asgard archaea.

Background

The origin of eukaryotes approximately two billion years ago was one of the most impactful evolutionary events in the history of life on Earth. This transition likely took place through the symbiosis of an archaeal host cell and an intracellular bacterium, which eventually became the mitochondrion. However, this topic has been difficult to study because of lack of information on close prokaryotic relatives of eukaryotes.

Anno 2019, a mere 13500 prokaryotes, of which a only ~350 are archaea, have been cultured. These numbers represent far less than 1% of all prokaryotic diversity inhabiting our planet, as revealed by the use deep sequencing techniques. Even after a century of cultivating microorganisms, the gap between who we know is out there and who can be cultured in the lab remains immense.

One of the many lineages of which no cultivated representatives exist are the Asgard archaea. This recently discovered group has been identified as the closest archaeal relative of eukaryotes. Obtaining novel cultivated representatives of this lineage could thus broaden our current knowledge and insight in how eukaryotes came to be.

Aim

At our lab, we have environmental samples in which Asgard archaea are present. Using these samples, we set up targeted (high throughput) isolation campaigns to enrich and purify these microorganisms from the samples. We aim to obtain new cultivated representatives of all uncultured clades of the Asgard archaea to allow a better understanding of their lifestyle and to shed more light into the origin of eukaryotes.

Techniques

  • General cultivation techniques
  • (Anaerobic) cultivation
  • Cell sorting
  • Flow cytometry
  • Sequencing
  • Bioinformatics techniques

BSc/MSc theses

Thesis projects are available for BSc or MSc students with interest in microbial cultivation, microbial ecology and bioinformatics. Experience with working on linux command line and programming (e.g. python, R) is appreciated but not necessary.