Denitrification aerobic

In recent years, availability of modem tools inclnding oxygen and ion-specific electrodes, culture vessels, and analytical methods has made it possible to determine the environmental conditions that support denitrification. These studies have shown that it is possible that a group of bacteria (mostly heterotrophic nitrifiers) are able to simultaneously utilize oxygen, nitrite, or nitrate as electron acceptors, even when oxygen levels in cultures approach near saturation levels (Zehr and Ward, 

Aerobic denitrification was described in Paracoccuspantotrophus (Rainey et al., 1999). The extent to which this process regulates overall nitrate loss is not known at this time. In wetlands, potentially this process can occur in aerobic portions of the soil profile. To dale Ihere is no evidence lhal Ihe aerobic denitrification occurs in wetland environments. 

Substantial loss of nitrogen has been observed in soil environment that is not favorable for ammonia volatilization and biological denitrification. 

Significant gaseous loss of fertilizer nitrogen has been observed under conditions that lead to accumulation of nitrite. 

Nitrite added to sterilized acid soils is rapidly converted to gaseous end products such as nitric oxide and nitrous oxide. 

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Robertson LA, JG Kuenen (1984) Aerobic denitrification a controversy revived. Arch Microbiol 139 351-354. 

Robertson, L. A., and Kuenen, J. G. (1990). Combined heterotrophic nitrification and aerobic denitrification in Thiosphaera pancotropha and other bacteria. Antonie Van Leenwenhoek 57, 139-152. 

These reactions are the terminal electron-transfer reactions during anaerobic respiration, the enzymes being part of a redox loop generating a proton-motive force capable of driving ATP synthesis. Periplasmic nitrate reductase (Nap) participates in cellular redox processes, aerobic denitrification, and nitrate scavenging. ... 

NapB. NapB is a subunit of the heterodimeric periplasmic nitrate reductase (NapAB) and transfers electrons to the catalytic NapA molybdoprotein. Nap systems are found in a number of bacteria, iucluding enterobacteria, aerobic denitrifiers, and nonsulfur purple photo synthetic bacteria. Their physiological function is different in these groups of bacteria and includes redox balancing using nitrate as an electron sink to dispose of excess rednctant, aerobic denitrification, and nitrate scavenging in nitrate-limited environments. 

Wehrfritz, J. M., ReiUy, A., Spiro, S., and Richardson, D.J. (1993). Purification of hydroxylamine oxidase from Thiosphaera pantotropha Identification of electron acceptors that couple heterotrophic nitrification to aerobic denitrification. FEES Letters 335, 246—250. 

Lloyd, D. L. (1993). Aerobic denitrification in soil and sediments From fallacies to trends. Ecol. Evol. 8, 352-356. 

Lloyd, D. (1993) Aerobic denitrification in soils and sediments from fallacies to facts. TREE 8, 352-6. 

Wehrfritz J-M, Carter JP, Soiro S, Richardson DJ (1997) Hydroxylamine oxidation in heterotro-phic nitrate-reducing soil bacteria and purification of hydroxylamine cytochrome c oxidore-ductase from Pseudomonas species. Arch Microbiol 166 421 —424 Wehrfritz J-M, Reilly A, Spiro S, Richardson DJ (1993) Purification of hydroxylamine oxidase from Thiosphaera pantotropha. Identification of electron acceptors that couple heterotrophic nitrification to aerobic denitrification. FEBS Lett 335 246-250 Wetzstein H-G, Ferguson SJ (1985) Respiration-dependent proton translocation and the mechanism of proton motive force generation in Nitrobacter winogradskyi. FEMS Microbiol Lett 30 87-92... 

Aerobic denitrification—under aerobic but low-oxygen conditions, the nitrite formed can be reduced to nitrous oxide by select chemoautotrophic and heterotrophic nitrifler... 

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