Researchers from University of Vienna found that Thaumarchaeota use organic nitrogen compound as supplement to their metabolism
Thaumarchaeota or the ammonia oxidizing archaea, are abundant marine microorganisms. However, it is less understood about the factors that allow thaumarchaeota to thrive in the ocean. Thaumarchaeota play a major role in the marine nitrogen cycle. These organisms convert ammonia to a more oxidized form—nitrite, in order to gain energy for growth. These ammonia oxidizing archaea make up a large part of the marine microbial community and grow in the oceans despite presence of low concentration of ammonium. Although Thaumarchaeota are a key part of the marine nitrogen cycle, the physiology of these small and enigmatic microorganisms is less understood. These organisms are considered to be metabolically restricted and depend on ammonia as an energy source.
Now, a team of researchers from the Max Planck Institute for Marine Microbiology in Bremen, Germany, the University of Vienna, the Georgia Institute for Technology, the Carl von Ossietzky University Oldenburg, and the University of Bremen revealed that marine ammonia oxidizing archaea can also use organic nitrogen sources. Katharina Kitzinger from the Max Planck Institute for Marine Microbiology stated that this was a leading research in demonstrating that both environmental and cultured marine ammonia oxidizing archaea can use cyanate, which is a simple organic nitrogen compound, as an additional energy source. Moreover, the team also revealed that these microorganisms also use urea, an organic nitrogen compound.
According to the researchers, the findings are vital as cyanate and urea are common nitrogen and energy sources in the oceans. The team also stated that the ability of Thaumarchaeota to use these compounds as supplement to their metabolism can be a major factor responsible for thriving of these organisms in the oceans. Kitzinger stated that the team is unsure of the mechanism behind the ability of marine ammonia oxidizing archaea to use cyanate. The organisms lack the typical enzyme repertoire that is required to use cyanate. Therefore, the team is focused on identifying the enzymes that allow marine ammonia oxidizing archaea to use cyanate. The research was published in the journal Nature Microbiology on December 10, 2018.