تثبيت النيتروجين
Nitrogen fixation plays an important role in the nitrogen cycle. "Azotobacter" also synthesizes some biologically active substances, including some phytohormones such as auxins, thereby stimulating plant growth. They also facilitate the mobility of heavy metals in the soil, thus enhancing bioremediation of soil from heavy metals, such as cadmium, mercury and lead. Some kinds of "Azotobacter" can also biodegrade chlorine-containing aromatic compounds, such as 2,4,6-trichlorophenol, which was previously used as an insecticide, fungicide, and herbicide, but later was found to have mutagenic and carcinogenic effects.