Diversity of anammox bacteria and contribution to the nitrogen loss in surface sediment

Conventional nitrification-denitrification treatment is a common way to treat nitrogen in wastewater, but this process is costly for low COD/N wastewaters due to the addition of air and external carbon-source. However, ammonia may alternatively be converted to dinitrogen gas by autotrophic bacteria utilizing aerobically autotrophically produced nitrite as an electron acceptor under anoxic conditions. Lab-scale sequencing batch biofilm reactors (SBBRs) inoculated with normal nitrifying sludge were employed to study the potential of an oxygen-limited autotrophic nitrification-denitrification process initiated with typical nitrifying sludge for treating a synthetic ammonia wastewater devoid of organic carbon in one step. The ring-laced fibrous carrier (length 0.32 m, surface area 3.4 m2/m) was fixed vertically in a 3 L reactor. Two different air supply modes were applied:continuous aeration to control dissolved oxygen at 1.5 mg/L and intermittent aeration. High nitrogen removals of more than 50% were obtained in both SBBRs. At an ammonia loading of 0.882 gm N/m2-day [hydraulic retention time (HRT) of 24 hr], the SBBR continuously aerated to 1.5 mg DO/L had slightly higher nitrogen removal (64%) than the intermittently alternated SBBR (55%). The main form of residual nitrogen in the effluent was ammonia, at concentrations of 25 mg/L and 37 mg N/L in continuous and intermittent aeration SBBRs, respectively. Ammonia was completely consumed when ammonia loading was reduced to 0.441 gm N/m2-day [HRT extended to 48 hr]. The competitive use of nitrite by aerobic nitrite oxidizing bacteria (ANOB) with anaerobic ammonia-oxidizing bacteria (anammox bacteria) during the expanded aeration period under low remaining ammonia concentration resulted in higher nitrate production and lower nitrogen loss in the continuous aeration SBBR than in the intermittent aeration SBBR. The nitrogen removal efficiencies in SBBRs with continuous and alternating aerated were 80% and 86% respectively. Specific microorganisms in the biofilm were characterized using fluorescence in situ hybridization. Aerobic ammonia-oxidizing bacteria (AAOB) occurred side by side with putative anammox bacteria (cells hybridizing with probe AMX820) throughout the biofilm, though ANOB were rarely detected.

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Global impact and application of the anaerobic ammonium-oxidizing (anammox) bacteria

Biochemical Society Transactions ◽

10.1042/bst0340174 ◽

2006 ◽

Vol 34 (1) ◽

pp. 174-178 ◽

Cited By ~ 64

Author(s):

H.J.M. Op den Camp ◽

B. Kartal ◽

D. Guven ◽

L.A.M.P. van Niftrik ◽

S.C.M. Haaijer ◽

...

Keyword(s):

Nitrogen Loss ◽

Low Cost ◽

High Strength ◽

Immunogold Labelling ◽

Primary Electron ◽

Freshwater Ecosystems ◽

Anammox Bacteria ◽

Ammonium Oxidation ◽

Short Supply ◽

Anammox Process

In the anaerobic ammonium oxidation (anammox) process, ammonia is oxidized with nitrite as primary electron acceptor under strictly anoxic conditions. The reaction is catalysed by a specialized group of planctomycete-like bacteria. These anammox bacteria use a complex reaction mechanism involving hydrazine as an intermediate. The reactions are assumed to be carried out in a unique prokaryotic organelle, the anammoxosome. This organelle is surrounded by ladderane lipids, which make the organelle nearly impermeable to hydrazine and protons. The localization of the major anammox protein, hydrazine oxidoreductase, was determined via immunogold labelling to be inside the anammoxosome. The anammox bacteria have been detected in many marine and freshwater ecosystems and were estimated to contribute up to 50% of oceanic nitrogen loss. Furthermore, the anammox process is currently implemented in water treatment for the low-cost removal of ammonia from high-strength waste streams. Recent findings suggested that the anammox bacteria may also use organic acids to convert nitrate and nitrite into dinitrogen gas when ammonia is in short supply.

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Small sinking particles control anammox rates in the Peruvian oxygen minimum zone

Nature Communications ◽

10.1038/s41467-021-23340-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Clarissa Karthäuser ◽

Soeren Ahmerkamp ◽

Hannah K. Marchant ◽

Laura A. Bristow ◽

Helena Hauss ◽

...

Keyword(s):

Nitrogen Loss ◽

Anammox Bacteria ◽

Small Particles ◽

Free Living ◽

Major Pathway ◽

Oxygen Minimum Zones ◽

Anoxic Waters ◽

Sinking Particles ◽

Minimum Zone ◽

Oxygen Minimum

AbstractAnaerobic oxidation of ammonium (anammox) in oxygen minimum zones (OMZs) is a major pathway of oceanic nitrogen loss. Ammonium released from sinking particles has been suggested to fuel this process. During cruises to the Peruvian OMZ in April–June 2017 we found that anammox rates are strongly correlated with the volume of small particles (128–512 µm), even though anammox bacteria were not directly associated with particles. This suggests that the relationship between anammox rates and particles is related to the ammonium released from particles by remineralization. To investigate this, ammonium release from particles was modelled and theoretical encounters of free-living anammox bacteria with ammonium in the particle boundary layer were calculated. These results indicated that small sinking particles could be responsible for ~75% of ammonium release in anoxic waters and that free-living anammox bacteria frequently encounter ammonium in the vicinity of smaller particles. This indicates a so far underestimated role of abundant, slow-sinking small particles in controlling oceanic nutrient budgets, and furthermore implies that observations of the volume of small particles could be used to estimate N-loss across large areas.

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Phylogenomics Suggests the Origin of Obligately Anaerobic Anammox Bacteria Correlates with the Great Oxidation Event

10.1101/2021.07.07.451387 ◽

2021 ◽

Author(s):

Tianhua Liao ◽

Sishuo Wang ◽

Haiwei Luo

Keyword(s):

Sequence Data ◽

Atmospheric Oxygen ◽

Nitrogen Loss ◽

Anaerobic Bacteria ◽

Anammox Bacteria ◽

Ammonium Oxidation ◽

Data Set ◽

Origin And Evolution ◽

Great Oxidation Event ◽

Obligate Anaerobic

The anaerobic ammonium oxidation (anammox) bacteria transform ammonium and nitrite to dinitrogen gas, and this obligate anaerobic process accounts for nearly half of global nitrogen loss. Yet its origin and evolution, which may give important insights into the biogeochemistry of early Earth, remains enigmatic. Here, we compile a comprehensive sequence data set of anammox bacteria, and confirm their single origin within the phylum Planctomycetes. After accommodating the uncertainties and factors influencing time estimates with different statistical methods, we estimate that anammox bacteria originated at 2.0 - 2.6 Ga, broadly coinciding with the Great Oxidation Event (GOE) which is thought to have fundamentally changed global biogeochemical cycles. We further show that during the origin of anammox bacteria, genes involved in oxidative stress, bioenergetics and anammox granules formation were recruited, which may have contributed to their survival in an increasingly oxic Earth. Our findings suggest the rising level of atmospheric oxygen, which made nitrite increasingly available, as a potential driving force for the emergence of anammox bacteria. This is one of the first studies that link GOE to the evolution of obligate anaerobic bacteria.

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Potential Contribution of Anammox to Nitrogen Loss from Paddy Soils in Southern China

Applied and Environmental Microbiology ◽

10.1128/aem.02664-14 ◽

2014 ◽

Vol 81 (3) ◽

pp. 938-947 ◽

Cited By ~ 84

Author(s):

Xiao-Ru Yang ◽

Hu Li ◽

San-An Nie ◽

Jian-Qiang Su ◽

Bo-Sen Weng ◽

...

Keyword(s):

Southern China ◽

Nitrogen Loss ◽

Terrestrial Ecosystems ◽

Dry Weight ◽

Paddy Soils ◽

Anammox Bacteria ◽

Potential Contribution ◽

Content Type ◽

Anammox Activity ◽

Anammox Process

ABSTRACTThe anaerobic oxidation of ammonium (anammox) process has been observed in diverse terrestrial ecosystems, while the contribution of anammox to N2production in paddy soils is not well documented. In this study, the anammox activity and the abundance and diversity of anammox bacteria were investigated to assess the anammox potential of 12 typical paddy soils collected in southern China. Anammox bacteria related to “CandidatusBrocadia” and “CandidatusKuenenia” and two novel unidentified clusters were detected, with “CandidatusBrocadia” comprising 50% of the anammox population. The prevalence of the anammox was confirmed by the quantitative PCR results based on hydrazine synthase (hzsB) genes, which showed that the abundance ranged from 1.16 × 104to 9.65 × 104copies per gram of dry weight. The anammox rates measured by the isotope-pairing technique ranged from 0.27 to 5.25 nmol N per gram of soil per hour in these paddy soils, which contributed 0.6 to 15% to soil N2production. It is estimated that a total loss of 2.50 × 106Mg N per year is linked to anammox in the paddy fields in southern China, which implied that ca. 10% of the applied ammonia fertilizers is lost via the anammox process. Anammox activity was significantly correlated with the abundance ofhzsBgenes, soil nitrate concentration, and C/N ratio. Additionally, ammonia concentration and pH were found to be significantly correlated with the anammox bacterial structure.

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Novel anammox bacteria and nitrogen loss from Lake Superior

Scientific Reports ◽

10.1038/s41598-017-12270-1 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 14

Author(s):

Sean A. Crowe ◽

Alexander H. Treusch ◽

Michael Forth ◽

Jiying Li ◽

Cedric Magen ◽

...

Keyword(s):

Nitrogen Loss ◽

Lake Superior ◽

Anammox Bacteria

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Sustained nitrogen loss in a symbiotic association of Comammox Nitrospira and Anammox bacteria

10.1101/2020.10.12.336248 ◽

2020 ◽

Author(s):

Ekaterina Y. Gottshall ◽

Sam J. Bryson ◽

Kathryn I. Cogert ◽

Matthieu Landreau ◽

Christopher J. Sedlacek ◽

...

Keyword(s):

Spatial Organization ◽

Nitrogen Loss ◽

Anammox Bacteria ◽

Symbiotic Association ◽

Ammonia Oxidizing Bacteria ◽

Ammonia Oxidizing Archaea ◽

Substrate Affinities ◽

Global Nitrogen Cycle ◽

Aerobic And Anaerobic ◽

Reproducible Manner

ABSTRACTThe discovery of complete aerobic and anaerobic ammonia-oxidizing bacteria (Comammox and Anammox) significantly altered our understanding of the global nitrogen cycle. A high affinity for ammonia (Km(app),NH3 ≈ 63nM) and oxygen place the first described isolate, Comammox Nitrospira inopinata in the same trophic category as organisms such as some ammonia-oxidizing archaea. However, N. inopinata has a relatively low affinity for nitrite (Km,NO2 ≈ 449.2μM) suggesting it would be less competitive for nitrite than other nitrite-consuming aerobes and anaerobes. We examined the ecological relevance of the disparate substrate affinities by coupling it with Anammox (Nitrospira inopinata and Brocadia anammoxidans, respectively). Synthetic communities were established in hydrogel granules in which Comammox grew in the aerobic outer layer to provide Anammox with nitrite in the inner anoxic core to form dinitrogen gas. This spatial organization was confirmed with FISH imaging, supporting a mutualistic or commensal relationship. Successful co-habitation of Comammox N. inopinata and Anammox in synthetic granules broadens our limited understanding of the interplay between these two species and offers potential biotechnological applications to study any type of bacterial pairings in a systematic and reproducible manner.

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Anammox bacteria drive fixed nitrogen loss in hadal trench sediments

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2104529118 ◽

2021 ◽

Vol 118 (46) ◽

pp. e2104529118

Author(s):

Bo Thamdrup ◽

Clemens Schauberger ◽

Morten Larsen ◽

Blandine Trouche ◽

Lois Maignien ◽

...

Keyword(s):

Organic Matter ◽

Surface Waters ◽

Nitrogen Loss ◽

Sediment Surface ◽

Anammox Bacteria ◽

Nitrogen Transformations ◽

Production Rates ◽

Fixed Nitrogen ◽

N Removal ◽

Aerobic Nitrification

Benthic N2 production by microbial denitrification and anammox is the largest sink for fixed nitrogen in the oceans. Most N2 production occurs on the continental shelves, where a high flux of reactive organic matter fuels the depletion of nitrate close to the sediment surface. By contrast, N2 production rates in abyssal sediments are low due to low inputs of reactive organics, and nitrogen transformations are dominated by aerobic nitrification and the release of nitrate to the bottom water. Here, we demonstrate that this trend is reversed in the deepest parts of the oceans, the hadal trenches, where focusing of reactive organic matter enhances benthic microbial activity. Thus, at ∼8-km depth in the Atacama Trench, underlying productive surface waters, nitrate is depleted within a few centimeters of the sediment surface, N2 production rates reach those reported from some continental margin sites, and fixed nitrogen loss is mainly conveyed by anammox bacteria. These bacteria are closely related to those known from shallow oxygen minimum zone waters, and comparison of activities measured in the laboratory and in situ suggest they are piezotolerant. Even the Kermadec Trench, underlying oligotrophic surface waters, exhibits substantial fixed N removal. Our results underline the role of hadal sediments as hot spots of deep-sea biological activity, revealing a fully functional benthic nitrogen cycle at high hydrostatic pressure and pointing to hadal sediments as a previously unexplored niche for anaerobic microbial ecology and diagenesis.

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Anaerobic ammonium oxidation (anammox) in different natural ecosystems

Biochemical Society Transactions ◽

10.1042/bst20110711 ◽

2011 ◽

Vol 39 (6) ◽

pp. 1811-1816 ◽

Cited By ~ 77

Author(s):

Bao-lan Hu ◽

Li-dong Shen ◽

Xiang-yang Xu ◽

Ping Zheng

Keyword(s):

Nitrogen Loss ◽

Terrestrial Ecosystems ◽

Influential Factors ◽

Anaerobic Ammonium Oxidation ◽

Anammox Bacteria ◽

Ammonium Oxidation ◽

Natural Ecosystems ◽

Natural Habitats ◽

Water Columns ◽

Anammox Process

Anammox (anaerobic ammonium oxidation), which is a reaction that oxidizes ammonium to dinitrogen gas using nitrite as the electron acceptor under anoxic conditions, was an important discovery in the nitrogen cycle. The reaction is mediated by a specialized group of planctomycete-like bacteria that were first discovered in man-made ecosystems. Subsequently, many studies have reported on the ubiquitous distribution of anammox bacteria in various natural habitats, including anoxic marine sediments and water columns, freshwater sediments and water columns, terrestrial ecosystems and some special ecosystems, such as petroleum reservoirs. Previous studies have estimated that the anammox process is responsible for 50% of the marine nitrogen loss. Recently, the anammox process was reported to account for 9–40% and 4–37% of the nitrogen loss in inland lakes and agricultural soils respectively. These findings indicate the great potential for the anammox process to occur in freshwater and terrestrial ecosystems. The distribution of different anammox bacteria and their contribution to nitrogen loss have been described in different natural habitats, demonstrating that the anammox process is strongly influenced by the local environmental conditions. The present mini-review summarizes the current knowledge of the ecological distribution of anammox bacteria, their contribution to nitrogen loss in various natural ecosystems and the effects of major influential factors on the anammox process.

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