Nitrosomonas europaea

Nitrosomonas europaea is a species of bacteria of the genus Nitrosomonas. It is referred to in German as ammonium bacterium.

The species is 1.1 to 1.8 microns in size and ellipsoidal. It has a polar flagellum that is not recognizable by light microscopy. Rarely Nitrosomonas europaea forms short chains.

Nitrosomonas europaea oxidizes ammonia and ammonium salts to nitrites. The species occurs in the soil and in the water, especially in waste water, widely used before.