🦠microbiology review

Nitrosomonas

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Nitrosomonas is a genus of ammonia-oxidizing bacteria that play a crucial role in the nitrogen cycle. They convert ammonia (NH3) into nitrite (NO2-) during the process of nitrification.

5 Must Know Facts For Your Next Test

  1. Nitrosomonas are chemolithoautotrophic bacteria, meaning they obtain energy by oxidizing inorganic molecules and fix carbon from CO2.
  2. These bacteria are commonly found in soil, freshwater, and wastewater treatment systems.
  3. The conversion of ammonia to nitrite by Nitrosomonas is an aerobic process, requiring oxygen.
  4. Nitrosomonas have a key enzyme called ammonia monooxygenase (AMO) which initiates the oxidation of ammonia.
  5. The activity of Nitrosomonas is essential for preventing the accumulation of toxic levels of ammonia in the environment.

Review Questions