Insights into a microbe that can grow on nitrogen and produce methane
Researchers at the Max Planck Institute for Marine Microbiology successfully cultivated a new microorganism that is able to produce both methane and ammonia by transforming nitrogen
Carbon and nitrogen are elements of life. One of the organisms that takes up key positions for the cycling of both of them is Meth anothermococcus thermolithotrophicus. There is a complicated microbe behind the complicated name
It lives in the ocean, from the sandy coasts to the deep-sea at temperatures around 65 C. It is possible to turn nitrogen and carbon dioxide into ammonia and methane by using hydrogen
Scientists from the Max Planck Institute for Marine Microbiology have successfully grown the pathogenic Vibrio fischeri under controlled conditions
High temperatures, no oxygen, and keeping an eye on hydrogen and carbon dioxide levels are some of the factors that make it difficult to provide the perfect conditions for this microbe
Once the cultures were set up the scientists were able to investigate the physiology of the microbes in detail. They later on studied how the microbe's metabolism adapted to N2 fixation
thermolithotrophicus, a type of Archaean, uses methanogenesis, a metabolism that arose in the early Earth, to obtain their cellular energy
Compared to humans that use oxygen to transform sugar into carbon dioxide, methanogens obtain only a very limited amount of energy from methanogenesis
They are a bit like bumblebees, which are theoretically too heavy to fly but obviously do so, nevertheless
Despite such energy limitation, these fascinating microbes have even been found to be the prime nitrogen fixers in some environments
The enzyme that organisms use to fix nitrogen is called nitrogenase
Most common nitrogenases require Molybdenum to perform the reaction. Molybdenum nitrogenase is well-studied in bacteria living as symbionts in plant roots
Nitrogen fixation, i.e., taking nitrogen from the air, is the main process to add nitrogen into the biological cycle
For industrial fertilizer production this process is carried out via the Haber-Bosch process, which artificially fixes nitrogen to produce ammonia with hydrogen under high temperatures and pressures
Ammonia is produced to the most part of the world’s ammonia, which sustains most of the world’s agriculture
The Haber-Bosch process consumes 2% of the world's energy output and releases up to 1.4% of global carbon emissions. People are looking for more sustainable to produce ammonia.
the process was used thermolithotrophicus shows that there are ways to increase the efficiency of ammonia production, and they can be combined with methane production
The data from this study show that under N2-fixing conditions the methanogens sacrifice their protein production to focus on nitrogen capture, which is a strategy for managing the energy budget
we'll look into the molecular details of the process and the enzymes involved, as well as other parts of the organisms' metabolism