Project: Syntrophy and symbiosis as mechanisms for growth and survival in deep terrestrial biosphere fracture systems

Despite being separated from the sun’s energy, life exists deep underground in cracks within the bedrock. This project will investigate how this life survives in an extremely low energy environment.

Facts about the project

Project manager
Professor Mark Dopson
Other project members
Professor Mats Åström, Linnaeus University, Stefan Bertilsson, Uppsala University
Participating organizations
Linnaeus University, Uppsala University
Swedish Research Council (VR) open call 2018
2019-01-01 to 2022-12-31
Environmental science (Department of Biology of Environmental Science, Faculty of Health and Life Sciences)

More about the project

The presence of large amounts of microorganisms up to several kilometers below the ground is well known. Despite the very low availability of energy sources and nutrients, these organisms are able to survive and grow. We also know that microbial processes in the deep biosphere are of major importance to the world's nutrient and energy flows. For instance, they contribute to cleaning contaminated groundwater while conversely they can negatively affect the long-term storage of toxic waste where microbial sulfide production can corrode the containers to be used in storage. In spite of the importance of the deep biosphere, it is one of the least understood ecosystems on earth and it likely contains an enormous and largely undiscovered, biodiversity.

Water-filled cracks in the bedrock constitute a very interesting and relevant environment in the deep biosphere. Microorganisms in these cracks grow by using hydrogen and carbon dioxide derived from natural geological processes. Due to the lack of food and energy sources, it is also likely that the deep biosphere microbes circulate nutrients between populations in order to survive.

In this project, the genetic properties of microorganisms will be studied in the complex microbial communities found in this environment. One method that will be used is 'meta-omics' that involves large-scale sequencing of DNA and RNA. In addition, stable isotopes will be used to find out which microorganisms break down different nutrients. Finally, electron microscopic images will reveal interactions between the microorganisms. In summary, my research shows how microbes interact with each other to get enough energy and nutrients to survive in this harsh environment.

Some of the more concrete questions that will be asked are:

  • How do newly discovered groups of microbes obtain energy to grow in the deep biosphere?
  • Can nutrients and sources of energy be redistributed between populations to be used as effectively as possible?
  • How can microorganisms lacking certain metabolic processes grow by exploiting other species' properties in so-called 'symbiosis'?

The project is part of the research of the research group Systems Biology of Microorganisms and of Linnaeus University Centre for Ecology and Evolution in Microbial model Systems (EEMiS).