Archives of Microbiology

, Volume 167, Issue 2, pp 106–111

Anaerobic ammonia oxidation with nitrogen dioxide by Nitrosomonas eutropha

  • Ingo Schmidt
  • E. Bock
Original paper

DOI: 10.1007/s002030050422

Cite this article as:
Schmidt, I. & Bock, E. Arch Microbiol (1997) 167: 106. doi:10.1007/s002030050422


Nitrosomonas eutropha, an obligately lithoautotrophic bacterium, was able to nitrify and denitrify simultaneously under anoxic conditions when gaseous nitrogen dioxide (NO2) was supplemented to the atmosphere. In the presence of gaseous NO2, ammonia was oxidized, nitrite and nitric oxide (NO) were formed, and hydroxylamine occurred as an intermediate. Between 40 and 60% of the produced nitrite was denitrified to dinitrogen (N2). Nitrous oxide (N2O) was shown to be an intermediate of denitrification. Under an N2 atmosphere supplemented with 25 ppm NO2 and 300 ppm CO2, the amount of cell protein increased by 0.87 mg protein per mmol ammonia oxidized, and the cell number of N. eutropha increased by 5.8 × 109 cells per mmol ammonia oxidized. In addition, the ATP and NADH content increased by 4.3 μmol ATP (g protein)–1 and 6.3 μmol NADH (g protein)–1 and was about the same in both anaerobically and aerobically grown cells. Without NO2, the ATP content decreased by 0.7 μmol (g protein)–1, and the NADH content decreased by 1.2 μmol (g protein)–1. NO was shown to inhibit anaerobic ammonia oxidation.

Key wordsNitrosomonasAnaerobic ammoniaoxidationAnaerobic cell growthNitrogen dioxideNitric oxideNitrous oxideDinitrogen

Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Ingo Schmidt
    • 1
  • E. Bock
    • 1
  1. 1.Institut für Allgemeine Botanik, Abteilung Mikrobiologie, Universität Hamburg, Ohnhorststrasse 18, D-22609 Hamburg, Germany Tel. +49-40-822-82424; Fax +49-40-822-82424DE