Beta
This nutritionally diverse subgroup includes Nitrosomonas, a genus of soil bacteria that play an important role in nitrogen recycling by oxidizing ammonium. Beta consist of several groups of aerobic or facultative bacteria that are often highly versatile in their degradation capacitites. Betaproteobacteria play a role in nitrogen fixation in various types of plants, oxidizing ammonium to produce nitrite- an important chemical for plant function. Many are found in waste, water, or soil.