Nitrogen is used to form amino acids, the building blocks of proteins, and nucleic acids, the building blocks of DNA and RNA. Mineralization-Also called ammonification because organic nitrogen compounds are converted into the inorganic compound ammonium. Denitrification- Bacteria live under anaerobic conditions, such as water logged soils or the bottom of oceans, lakes, and swamps. Nitrogen Fixation- Converts nitrogen from the atmosphere into ammonia.