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Alain Stintzi - One of the best experts on this subject based on the ideXlab platform.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    Abstract This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

Eva Spieck - One of the best experts on this subject based on the ideXlab platform.

  • Low Temperature and Neutral pH Define "Candidatus Nitrotoga sp." as a Competitive Nitrite Oxidizer in Coculture with Nitrospira defluvii.
    Applied and environmental microbiology, 2019
    Co-Authors: Simone Wegen, Eva Spieck
    Abstract:

    ABSTRACT Nitrification is an essential process for N removal in activated sludge to avoid toxicity of ammonium and Nitrite. Besides Nitrospira, “Candidatus Nitrotoga” has been identified as a key Nitrite-oxidizing bacterium (NOB) performing the second step of nitrification, Nitrite oxidation to nitrate, in wastewater treatment plants (WWTPs). However, the driving forces for the dominance of Nitrotoga in certain plants have often remained unclear and could not be explained solely by temperature effects. In this study, we characterized the physiology of the ammonium-dependent Nitrotoga sp. BS with regard to temperature and pH variations and evaluated its competitiveness against Nitrospira defluvii. Both NOB originated from the same WWTP and shared a comparable pH optimum of 7.3. Based on these results, coculturing experiments with these NOB were performed in batch reactors operated at either 17°C or 22°C to compare their abundances under optimal (pH 7.4) or suboptimal (pH 6.4) conditions using 1 mM Nitrite. As revealed by quantitative PCR (qPCR), fluorescence in situ hybridization (FISH), and 16S amplicon sequencing, Nitrotoga sp. BS was clearly favored by its optimal growth parameters and dominated over Ns. defluvii at pH 7.4 and 17°C, whereas a pH of 6.4 was more selective for Ns. defluvii. Our synthetic communities revealed that niche differentiation of NOB is influenced by a complex interaction of environmental parameters and has to be evaluated for single species. IMPORTANCE “Ca. Nitrotoga” is a NOB of high environmental relevance, but physiological data exist for only a few representatives. Initially, it was detected in specialized niches of low temperature and low Nitrite concentrations, but later on, its ubiquitous distribution revealed its critical role for N removal in engineered systems like WWTPs. In this study, we analyzed the competition between Nitrotoga and Nitrospira in bioreactors and identified conditions where the K strategist Ns. defluvii was almost replaced by Nitrotoga sp. BS. We show that the pH value is an important factor that regulates the composition of the Nitrite-oxidizing enrichment with a dominance of Nitrotoga sp. BS versus Ns. defluvii at a neutral pH of 7.4 in combination with a temperature of 17°C. The physiological diversity of novel Nitrotoga cultures improves our knowledge about niche differentiation of NOB with regard to functional nitrification under suboptimal conditions.

  • Relevance and Diversity of Nitrospira Populations in Biofilters of Brackish RAS
    2016
    Co-Authors: Myriam Kruse, Eva Spieck, Sabine Keuter, Till Eggers, Evert Bakker, Andre ́ Lipski
    Abstract:

    Lithoautotrophic Nitrite-oxidizing bacterial populations from moving-bed biofilters of brackish recirculation aquaculture systems (RAS; shrimp and barramundi) were tested for their metabolic activity and phylogenetic diversity. Samples from the biofilters were labeled with 13C-bicarbonate and supplemented with Nitrite at concentrations of 0.3, 3 and 10 mM, and incubated at 17 and 28uC, respectively. The biofilm material was analyzed by fatty acid methyl ester- stable isotope probing (FAME-SIP). High portions of up to 45 % of Nitrospira-related labeled lipid markers were found confirming that Nitrospira is the major autotrophic Nitrite Oxidizer in these brackish systems with high nitrogen loads. Other Nitrite-oxidizing bacteria such as Nitrobacter or Nitrotoga were functionally not relevant in the investigated biofilters. Nitrospira-related 16S rRNA gene sequences were obtained from the samples with 10 mM Nitrite and analyzed by a cloning approach. Sequence studies revealed four different phylogenetic clusters within the marine sublineage IV of Nitrospira, though most sequences clustered with the type strain of Nitrospira marina and with a strain isolated from a marine RAS. Three lipids dominated the whole fatty acid profiles of Nitrite-oxidizing marine and brackish enrichments of Nitrospira sublineage IV organisms. The membranes included two marker lipids (16:1 cis7 and 16:1 cis11) combined with the non-specific acid 16:0 as major compounds and confirmed these marker lipids as characteristic for sublineage IV species. The predominant labeling of these characteristic fatty acids and the phylogenetic sequence analyses of the marine Nitrospira sublineage IV identifie

  • the Nitrite oxidizing community in activated sludge from a municipal wastewater treatment plant determined by fatty acid methyl ester stable isotope probing
    Systematic and Applied Microbiology, 2013
    Co-Authors: Myriam Kruse, Eva Spieck, Evert P Bakker, Till Eggers, Sabine Zumbragel, André Lipski
    Abstract:

    Abstract Metabolically-active autotrophic Nitrite Oxidizers from activated sludge were labeled with 13 C-bicarbonate under exposure to different temperatures and Nitrite concentrations. The labeled samples were characterized by FAME-SIP (fatty acid methyl ester-stable isotope probing). The compound cis -11-palmitoleic acid, which is the major lipid of the most abundant Nitrite Oxidizer in activated sludge, Candidatus Nitrospira defluvii, showed 13 C-incorporation in all samples exposed to 3 mM Nitrite. Subsequently, the lipid cis -7-palmitoleic acid was labeled, and it indicated the activity of a Nitrite Oxidizer that was different from the known Nitrospira taxa in activated sludge. The highest incorporation of cis -7-palmitoleic acid label was found after incubation with a Nitrite concentration of 0.3 mM at 17 and 22 °C. While activity of Nitrobacter populations could not be detected by the FAME-SIP approach, an unknown Nitrite Oxidizer with the major lipid cis -9 isomer of palmitoleic acid exhibited 13 C-incorporation at 28 °C with 30 mM Nitrite. These results indicated flexibility of Nitrite-oxidizing guilds in a complex community responding to different conditions. Labeled lipids so far not described for activated sludge-associated nitrifiers indicated the presence of unknown Nitrite Oxidizers in this habitat. The FAME-SIP-based information can be used to define appropriate conditions for the enrichment of Nitrite-oxidizing guilds from complex samples.

  • relevance and diversity of nitrospira populations in biofilters of brackish ras
    PLOS ONE, 2013
    Co-Authors: Myriam Kruse, Eva Spieck, Sabine Keuter, Evert P Bakker, Till Eggers, André Lipski
    Abstract:

    Lithoautotrophic Nitrite-oxidizing bacterial populations from moving-bed biofilters of brackish recirculation aquaculture systems (RAS; shrimp and barramundi) were tested for their metabolic activity and phylogenetic diversity. Samples from the biofilters were labeled with 13C-bicarbonate and supplemented with Nitrite at concentrations of 0.3, 3 and 10 mM, and incubated at 17 and 28°C, respectively. The biofilm material was analyzed by fatty acid methyl ester - stable isotope probing (FAME-SIP). High portions of up to 45% of Nitrospira-related labeled lipid markers were found confirming that Nitrospira is the major autotrophic Nitrite Oxidizer in these brackish systems with high nitrogen loads. Other Nitrite-oxidizing bacteria such as Nitrobacter or Nitrotoga were functionally not relevant in the investigated biofilters. Nitrospira-related 16S rRNA gene sequences were obtained from the samples with 10 mM Nitrite and analyzed by a cloning approach. Sequence studies revealed four different phylogenetic clusters within the marine sublineage IV of Nitrospira, though most sequences clustered with the type strain of Nitrospira marina and with a strain isolated from a marine RAS. Three lipids dominated the whole fatty acid profiles of Nitrite-oxidizing marine and brackish enrichments of Nitrospira sublineage IV organisms. The membranes included two marker lipids (16∶1 cis7 and 16∶1 cis11) combined with the non-specific acid 16∶0 as major compounds and confirmed these marker lipids as characteristic for sublineage IV species. The predominant labeling of these characteristic fatty acids and the phylogenetic sequence analyses of the marine Nitrospira sublineage IV identified organisms of this sublineage as main autotrophic Nitrite-Oxidizers in the investigated brackish biofilter systems.

  • The Genome of Nitrospina gracilis Illuminates the Metabolism and Evolution of the Major Marine Nitrite Oxidizer.
    Frontiers in microbiology, 2013
    Co-Authors: Boris Nowka, Eva Spieck, Thomas Rattei, Holger Daims
    Abstract:

    In marine systems, nitrate is the major reservoir of inorganic fixed nitrogen. The only known biological nitrate-forming reaction is Nitrite oxidation, but despite its importance, our knowledge of the organisms catalyzing this key process in the marine N-cycle is very limited. The most frequently encountered marine NOB are related to Nitrospina gracilis, an aerobic chemolithoautotrophic bacterium isolated from ocean surface waters. To date, limited physiological and genomic data for this organism were available and its phylogenetic affiliation was uncertain. In this study, the draft genome sequence of Nitrospina gracilis strain 3/211 was obtained. Unexpectedly for an aerobic organism, N. gracilis lacks classical reactive oxygen defense mechanisms and uses the reductive tricarboxylic acid cycle for carbon fixation. These features indicate microaerophilic ancestry and are consistent with the presence of Nitrospina in marine oxygen minimum zones. Fixed carbon is stored intracellularly as glycogen, but genes for utilizing external organic carbon sources were not identified. N. gracilis also contains a full gene set for oxidative phosphorylation with oxygen as terminal electron acceptor and for reverse electron transport from Nitrite to NADH. A novel variation of complex I may catalyze the required reverse electron flow to low-potential ferredoxin. Interestingly, comparative genomics indicated a strong evolutionary link between Nitrospina, the Nitrite-oxidizing genus Nitrospira, and anaerobic ammonium Oxidizers, apparently including the horizontal transfer of a periplasmically oriented Nitrite oxidoreductase and other key genes for Nitrite oxidation at an early evolutionary stage. Further, detailed phylogenetic analyses using concatenated marker genes provided evidence that Nitrospina forms a novel bacterial phylum, for which we propose the name Nitrospinae.

V Hoang - One of the best experts on this subject based on the ideXlab platform.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    Abstract This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

Robert Delatolla - One of the best experts on this subject based on the ideXlab platform.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    Abstract This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

Turki Abujamel - One of the best experts on this subject based on the ideXlab platform.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    Abstract This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

  • nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
    Water Research, 2014
    Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain Stintzi
    Abstract:

    This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia Oxidizers) as well as Nitrospira (Nitrite Oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.