Comparison of different aerobic granular sludge types for activated sludge nitrification bioaugmentation potential

The study reports diversity in nitrifying microbial enrichments from low (0·5–5‰) and high (18–35‰) saline ecosystems. Microbial community profiling of ammonia‐oxidizing bacteria (AOB) and nitrite‐oxidizing bacteria (NOB) enrichments was analysed by sequencing 16S rRNA and was processed using Mothur pipeline. The α‐diversity indices showed the richness of nitrifying bacterial consortia from the high saline environment and were clustering based on the source of the sample. AOB and NOB enrichments from both the environments showed diverse lineages of phyla distributed in both groups with 38 and 34 phyla from low saline and 53 and 40 phyla in high saline sources, respectively. At class level, α‐ and γ‐proteobacteria were found to be more dominant in both the enrichments. AOBs and NOBs in enrichments from low saline environments were dominated by Nitrosomonadaceae, Gallionellaceae (Nitrotoga sp.) and Ectothiorhodospiraceae and Nitrospira, respectively. Though Chromatiaceae were present in both AOB and NOB enrichments, Nitrosoglobus and Nitrosococcus dominated the AOBs while NOBs were dominated by uncultured genera, whereas Rhizobiales were found in both the enrichments. AOBs and NOBs in enrichments from high saline environments were dominated by Nitrospira‐like AOBs, Nitrosomonas and Nitrosococcus genera, whereas ammonia‐oxidizing archaea (AOA) group included Nitrosopumilus and Nitrososphaera genera comprising and Nitrospirae, respectively. The majority of the genera obtained in both the salinities were found to be either uncultured or unclassified groups. Results of the study suggest that the AOB and NOB consortia have unique and diverse microbes in each of the enrichments, capable of functioning in aquaculture systems practised at different salinities (0–60 ppt).

show abstract

“…2015; Figdore et al . 2017). Among the nitrite‐oxidizing bacteria observed in the present study, Nitrospira sp.…”

Section: Resultsmentioning

confidence: 99%

Abundance, community structure and diversity of nitrifying bacterial enrichments from low and high saline brackishwater environments

Patil

Baskaran

Vinay

et al. 2021

Lett Appl Microbiol

View full text Add to dashboard Cite

show abstract

“…Nitrotoga in a variety of nitrogen removal bioreactors. Within wastewater treatment systems, Nitrotoga -like bacteria have been found in biofilms, biofilters, granular sludge, and suspended floc sludge. − ,, They were also found in the novel partial nitritation–anammox process that has been intensively studied for shortcut nitrogen removal via the nitrite pathway in next-generation WWTPs. , However, environmental factors that are critical to the presence and absence of Nitrotoga -like bacteria in activated sludge processes have not been investigated to date.…”

Section: Introductionmentioning

confidence: 99%

Critical Factors Facilitating Candidatus Nitrotoga To Be Prevalent Nitrite-Oxidizing Bacteria in Activated Sludge

Zheng

et al. 2020

Environ. Sci. Technol.

View full text Add to dashboard Cite

Nitrite oxidation is the primary pathway that generates nitrate in engineered systems. However, little is known about the role of a novel nitrite-oxidizing bacteria (NOB) genus Candidatus Nitrotoga in activated sludge systems. To elucidate key factors that impact NOB community composition, laboratory-scale sequencing batch reactors (SBRs) were designed and operated under the same conditions as real wastewater treatment plants to achieve considerable nitrogen removal and similar community; then, different conditions including temperature (T), dissolved oxygen (DO), free nitrous acid (FNA), and free ammonia (FA) were applied. The 16S rRNA gene-based PCR and sequence analysis illustrated that Ca. Nitrotoga were abundant even at ambient temperature, thus further challenging the previous conception of them being solely cold-adapted. Ca. Nitrotoga are less competitive than Nitrospira during oxygen deficiency, indicating its lower affinity to dissolved oxygen. Ca. Nitrotoga are the dominant nitrite oxidizers under regular exposure to FNA and FA due to their relatively higher resistance than other NOB toward these two effective biocides. Therefore, this study demonstrates that Ca. Nitrotoga can play an important role in biological nitrogen removal and also highlights the need for multiple strategies for NOB suppression for the next-generation, shortcut nitrogen removal.

show abstract

“…Recent 16S rRNA-based molecular surveys have identified Ca. Nitrotoga-like sequences in a wide range of habitats, including: glacial soils [14][15][16][17], an underground cave [18], a freshwater seep [19], drinking water [20,21], a subglacial Antarctic lake [22], Yellow Sea seawater [23], salt marsh sediments [24], rivers [25,26], and various wastewater treatment plants (WWTPs) or sequence batch reactors [13,[27][28][29][30][31][32]. The relative abundance of Ca.…”

Section: Introductionmentioning

confidence: 99%

Genomic profiling of four cultivated Candidatus Nitrotoga spp. predicts broad metabolic potential and environmental distribution

Boddicker

Mosier

2018

The ISME Journal

View full text Add to dashboard Cite

Nitrite-oxidizing bacteria (NOB) play a critical role in the mitigation of nitrogen pollution by metabolizing nitrite to nitrate, which is removed via assimilation, denitrification, or anammox. Recent studies showed that NOB are phylogenetically and metabolically diverse, yet most of our knowledge of NOB comes from only a few cultured representatives. Using cultivation and genomic sequencing, we identified four putative Candidatus Nitrotoga NOB species from freshwater sediments and water column samples in Colorado, USA. Genome analyses indicated highly conserved 16S rRNA gene sequences, but broad metabolic potential including genes for nitrogen, sulfur, hydrogen, and organic carbon metabolism. Genomic predictions suggested that Ca. Nitrotoga can metabolize in low oxygen or anoxic conditions, which may support an expanded environmental niche for Ca. Nitrotoga similar to other NOB. An array of antibiotic and metal resistance genes likely allows Ca. Nitrotoga to withstand environmental pressures in impacted systems. Phylogenetic analyses highlighted a deeply divergent nitrite oxidoreductase alpha subunit (NxrA), suggesting a novel evolutionary trajectory for Ca. Nitrotoga separate from any other NOB and further revealing the complex evolutionary history of nitrite oxidation in the bacterial domain. Ca. Nitrotoga-like 16S rRNA gene sequences were prevalent in globally distributed environments over a range of reported temperatures. This work considerably expands our knowledge of the Ca. Nitrotoga genus and suggests that their contribution to nitrogen cycling should be considered alongside other NOB in wide variety of habitats.

show abstract

Comparison of different aerobic granular sludge types for activated sludge nitrification bioaugmentation potential

Cited by 40 publications

References 41 publications

Abundance, community structure and diversity of nitrifying bacterial enrichments from low and high saline brackishwater environments

Abundance, community structure and diversity of nitrifying bacterial enrichments from low and high saline brackishwater environments

Critical Factors Facilitating Candidatus Nitrotoga To Be Prevalent Nitrite-Oxidizing Bacteria in Activated Sludge

Genomic profiling of four cultivated Candidatus Nitrotoga spp. predicts broad metabolic potential and environmental distribution

Contact Info

Product

Resources

About