We are now attempting to isolate comammox bacteria from environmental samples using guanidine, as only one strain is currently available in pure culture. This seems particularly promising as none of the other nitrifier strains we tested could grow with guanidine.

We will also investigate whether adding guanidine to agricultural fertilizers increases the abundance of comammox bacteria in arable soils, thereby reducing agricultural nitrous oxide emissions as comammox nitrifiers low amounts of this greenhouse gas www.nature.com/articles/s41...