Denitrification

Definition

Denitrification is the microbial process of converting nitrate (NO3-) into nitrogen gas (N2), thus removing bioavailable nitrogen from ecosystems. This process is part of the nitrogen cycle and primarily occurs under anaerobic conditions.

5 Must Know Facts For Your Next Test

1. Denitrification is carried out by facultative anaerobic bacteria such as Pseudomonas and Paracoccus.
2. The end products of denitrification include gaseous forms like N2, N2O, and NO.
3. Denitrification typically occurs in environments with low oxygen levels, such as waterlogged soils and sediments.
4. This process helps regulate the amount of nitrogen available in various ecosystems, thus preventing nutrient overloading.
5. Enzymes involved in denitrification include nitrate reductase, nitrite reductase, nitric oxide reductase, and nitrous oxide reductase.

Review Questions

• What types of bacteria are primarily responsible for denitrification?
• What conditions favor the process of denitrification?
• Name at least two enzymes involved in the denitrification process.

Related terms

Nitrification: The microbial conversion of ammonium (NH4+) to nitrate (NO3-).

Nitrogen Fixation:

The process through which atmospheric nitrogen (N2) is converted into ammonia (NH3) by certain bacteria.

Anaerobic Respiration:

Respiration using electron acceptors other than oxygen, often occurring in oxygen-depleted environments.