Production of NO, N2O and N2 by extracted soil bacteria, regulation by NO2- and O2 concentrations

Nicholas Morley, Elizabeth M. Baggs, Peter Dorsch, Lars Bakken

Research output: Contribution to journalArticle

99 Citations (Scopus)

Abstract

The oxygen control of denitrification and its emission of NO/N2O/N-2 was investigated by incubation of Nycodenz-extracted soil bacteria in an incubation robot which monitors O-2, NO, N2O and N-2 concentrations (in He+O-2 atmosphere). Two consecutive incubations were undertaken to determine (1) the regulation of denitrification by O-2 and NO2- during respiratory O-2 depletion and (2) the effects of re-exposure to O-2 of cultures with fully expressed denitrification proteome. Early denitrification was only detected (as NO and N2O) at <= 80 mu M O-2 in treatments with NO2-, and the rates were three orders of magnitude lower than the rates observed after oxygen depletion (with N-2 as the primary product). When re-exposed to O-2, the cultures continued to denitrify (8-55% of the rates during the foregoing anoxic phase), but its main product was N2O. The N2O reductase activity recovered as oxygen was being depleted. The results suggest that expression of the denitrifying proteome may result in significant subsequent aerobic denitrification, and this has profound implications for the understanding and modelling of denitrification and N2O emission. Short anoxic spells caused by transient flooding during rainfall, could lead to subsequent unbalanced aerobic denitrification, in which N2O is a major end product.

Original languageEnglish
Pages (from-to)102-112
Number of pages11
JournalFEMS Microbiology Ecology
Volume65
Issue number1
Early online date28 Jun 2008
DOIs
Publication statusPublished - Jul 2008

Keywords

  • aerobic denitrification
  • oxygen
  • nitrite
  • nitrous oxide
  • nitric oxide
  • dinitrogen
  • ammonia-oxidizing bacteria
  • nitrous-oxide production
  • thiosphaera-pantotropha
  • paracoccus-denitrificans
  • denitrifying bacteria
  • pseudomonas-stutzeri
  • anaerobic conditions
  • continuous-culture

Cite this

Production of NO, N2O and N2 by extracted soil bacteria, regulation by NO2- and O2 concentrations. / Morley, Nicholas; Baggs, Elizabeth M.; Dorsch, Peter; Bakken, Lars.

In: FEMS Microbiology Ecology, Vol. 65, No. 1, 07.2008, p. 102-112.

Research output: Contribution to journalArticle

Morley, Nicholas ; Baggs, Elizabeth M. ; Dorsch, Peter ; Bakken, Lars. / Production of NO, N2O and N2 by extracted soil bacteria, regulation by NO2- and O2 concentrations. In: FEMS Microbiology Ecology. 2008 ; Vol. 65, No. 1. pp. 102-112.
@article{784fb661a57342e393acb569dd680040,
title = "Production of NO, N2O and N2 by extracted soil bacteria, regulation by NO2- and O2 concentrations",
abstract = "The oxygen control of denitrification and its emission of NO/N2O/N-2 was investigated by incubation of Nycodenz-extracted soil bacteria in an incubation robot which monitors O-2, NO, N2O and N-2 concentrations (in He+O-2 atmosphere). Two consecutive incubations were undertaken to determine (1) the regulation of denitrification by O-2 and NO2- during respiratory O-2 depletion and (2) the effects of re-exposure to O-2 of cultures with fully expressed denitrification proteome. Early denitrification was only detected (as NO and N2O) at <= 80 mu M O-2 in treatments with NO2-, and the rates were three orders of magnitude lower than the rates observed after oxygen depletion (with N-2 as the primary product). When re-exposed to O-2, the cultures continued to denitrify (8-55{\%} of the rates during the foregoing anoxic phase), but its main product was N2O. The N2O reductase activity recovered as oxygen was being depleted. The results suggest that expression of the denitrifying proteome may result in significant subsequent aerobic denitrification, and this has profound implications for the understanding and modelling of denitrification and N2O emission. Short anoxic spells caused by transient flooding during rainfall, could lead to subsequent unbalanced aerobic denitrification, in which N2O is a major end product.",
keywords = "aerobic denitrification, oxygen, nitrite, nitrous oxide, nitric oxide, dinitrogen, ammonia-oxidizing bacteria, nitrous-oxide production, thiosphaera-pantotropha, paracoccus-denitrificans, denitrifying bacteria, pseudomonas-stutzeri, anaerobic conditions, continuous-culture",
author = "Nicholas Morley and Baggs, {Elizabeth M.} and Peter Dorsch and Lars Bakken",
year = "2008",
month = "7",
doi = "10.1111/j.1574-6941.2008.00495.x",
language = "English",
volume = "65",
pages = "102--112",
journal = "FEMS Microbiology Ecology",
issn = "1574-6941",
publisher = "Oxford University Press",
number = "1",

}

TY - JOUR

T1 - Production of NO, N2O and N2 by extracted soil bacteria, regulation by NO2- and O2 concentrations

AU - Morley, Nicholas

AU - Baggs, Elizabeth M.

AU - Dorsch, Peter

AU - Bakken, Lars

PY - 2008/7

Y1 - 2008/7

N2 - The oxygen control of denitrification and its emission of NO/N2O/N-2 was investigated by incubation of Nycodenz-extracted soil bacteria in an incubation robot which monitors O-2, NO, N2O and N-2 concentrations (in He+O-2 atmosphere). Two consecutive incubations were undertaken to determine (1) the regulation of denitrification by O-2 and NO2- during respiratory O-2 depletion and (2) the effects of re-exposure to O-2 of cultures with fully expressed denitrification proteome. Early denitrification was only detected (as NO and N2O) at <= 80 mu M O-2 in treatments with NO2-, and the rates were three orders of magnitude lower than the rates observed after oxygen depletion (with N-2 as the primary product). When re-exposed to O-2, the cultures continued to denitrify (8-55% of the rates during the foregoing anoxic phase), but its main product was N2O. The N2O reductase activity recovered as oxygen was being depleted. The results suggest that expression of the denitrifying proteome may result in significant subsequent aerobic denitrification, and this has profound implications for the understanding and modelling of denitrification and N2O emission. Short anoxic spells caused by transient flooding during rainfall, could lead to subsequent unbalanced aerobic denitrification, in which N2O is a major end product.

AB - The oxygen control of denitrification and its emission of NO/N2O/N-2 was investigated by incubation of Nycodenz-extracted soil bacteria in an incubation robot which monitors O-2, NO, N2O and N-2 concentrations (in He+O-2 atmosphere). Two consecutive incubations were undertaken to determine (1) the regulation of denitrification by O-2 and NO2- during respiratory O-2 depletion and (2) the effects of re-exposure to O-2 of cultures with fully expressed denitrification proteome. Early denitrification was only detected (as NO and N2O) at <= 80 mu M O-2 in treatments with NO2-, and the rates were three orders of magnitude lower than the rates observed after oxygen depletion (with N-2 as the primary product). When re-exposed to O-2, the cultures continued to denitrify (8-55% of the rates during the foregoing anoxic phase), but its main product was N2O. The N2O reductase activity recovered as oxygen was being depleted. The results suggest that expression of the denitrifying proteome may result in significant subsequent aerobic denitrification, and this has profound implications for the understanding and modelling of denitrification and N2O emission. Short anoxic spells caused by transient flooding during rainfall, could lead to subsequent unbalanced aerobic denitrification, in which N2O is a major end product.

KW - aerobic denitrification

KW - oxygen

KW - nitrite

KW - nitrous oxide

KW - nitric oxide

KW - dinitrogen

KW - ammonia-oxidizing bacteria

KW - nitrous-oxide production

KW - thiosphaera-pantotropha

KW - paracoccus-denitrificans

KW - denitrifying bacteria

KW - pseudomonas-stutzeri

KW - anaerobic conditions

KW - continuous-culture

U2 - 10.1111/j.1574-6941.2008.00495.x

DO - 10.1111/j.1574-6941.2008.00495.x

M3 - Article

VL - 65

SP - 102

EP - 112

JO - FEMS Microbiology Ecology

JF - FEMS Microbiology Ecology

SN - 1574-6941

IS - 1

ER -