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Alain Stintzi - One of the best experts on this subject based on the ideXlab platform.
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Nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
Water Research, 2014Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain StintziAbstract: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.
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Nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
Water Research, 2014Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain StintziAbstract: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.
Rudolf Amann - One of the best experts on this subject based on the ideXlab platform.
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In situ distribution and activity of Nitrifying Bacteria in freshwater sediment
Environmental Microbiology, 2003Co-Authors: Dörte Altmann, Peter Stief, Rudolf Amann, Dirk De Beer, Andreas SchrammAbstract:Summary Nitrification was investigated in a model freshwater sediment by the combined use of microsensors and fluorescence in situ hybridization with rRNA-targeted oligonucleotide probes. In situ nitrification activity was restricted mainly to the upper 2 mm of the sediment and coincided with the maximum abundance of Nitrifying Bacteria, i.e. 1.5 × 107 cells cm−3 for ammonia-oxidizing Beta-proteoBacteria (AOB) and 8.6 × 107 cells cm−3 for Nitrospira-like nitrite-oxidizing Bacteria (NOB). Cell numbers of AOB decreased more rapidly with depth than numbers of NOB. For the first time, Nitrospira-like Bacteria could be quantified and correlated with in situ nitrite oxidation rates in a sediment. Estimated cell-specific nitrite oxidation rates were 1.2–2.7 fmol NO2– cell−1 h−1.
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microenvironments and distribution of Nitrifying Bacteria in a membrane bound biofilm
Environmental Microbiology, 2000Co-Authors: Dirk De Beer, Armin Gieseke, Rudolf AmannAbstract:Summary The distribution of Nitrifying Bacteria of the genera Nitrosomonas, Nitrosospira, Nitrobacter and Nitrospira was investigated in a membrane-bound biofilm system with opposed supply of oxygen and ammonium. Gradients of oxygen, pH, nitrite and nitrate were determined by means of microsensors while the Nitrifying populations along these gradients were identified and quantified using fluorescence in situ hybridization (FISH) in combination with confocal laser scanning microscopy. The oxic part of the biofilm which was subjected to high ammonium and nitrite concentrations was dominated by Nitrosomonas europaea-like ammonia oxidizers and by members of the genus Nitrobacter. Cell numbers of Nitrosospira sp. were 1‐2 orders of magnitude lower than those of N. europaea. Nitrospira sp. were virtually absent in this part of the biofilm, whereas they were most abundant at the oxic‐anoxic interface. In the totally anoxic part of the biofilm, cell numbers of all nitrifiers were relatively low. These observations support the hypothesis that N. europaea and Nitrobacter sp. can out-compete Nitrosospira and Nitrospira spp. at high substrate and oxygen concentrations. Additionally, they suggest microaerophilic behaviour of yet uncultured Nitrospira sp. as a factor of its environmental competitiveness.
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microscale distribution of populations and activities of nitrosospira and nitrospira spp along a macroscale gradient in a Nitrifying bioreactor quantification by in situ hybridization and the use of microsensors
Applied and Environmental Microbiology, 1999Co-Authors: Andreas Schramm, Dirk De Beer, J C Van Den Heuvel, Spp Simon Ottengraf, Rudolf AmannAbstract:The change of activity and abundance of Nitrosospira and Nitrospira spp. along a bulk water gradient in a Nitrifying fluidized bed reactor was analyzed by a combination of microsensor measurements and fluorescence in situ hybridization. Nitrifying Bacteria were immobilized in Bacterial aggregates that remained in fixed positions within the reactor column due to the flow regimen. Nitrification occurred in a narrow zone of 100 to 150 mm on the surface of these aggregates, the same layer that contained an extremely dense community of Nitrifying Bacteria. The central part of the aggregates was inactive, and significantly fewer nitrifiers were found there. Under conditions prevailing in the reactor, i.e., when ammonium was limiting, ammonium was completely oxidized to nitrate within the active layer of the aggregates, the rates decreasing with increasing reactor height. To analyze the nitrification potential, profiles were also recorded in aggregates subjected to a shortterm incubation under elevated substrate concentrations. This led to a shift in activity from ammonium to nitrite oxidation along the reactor and correlated well with the distribution of the Nitrifying population. Along the whole reactor, the numbers of ammonia-oxidizing Bacteria decreased, while the numbers of nitriteoxidizing Bacteria increased. Finally, volumetric reaction rates were calculated from microprofiles and related to cell numbers of Nitrifying Bacteria in the active shell. Therefore, it was possible for the first time to estimate the cell-specific activity of Nitrosospira spp. and hitherto-uncultured Nitrospira-like Bacteria in situ.
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structure and function of a Nitrifying biofilm as determined by microelectrodes and fluorescent oligonucleotide probes
Water Science and Technology, 1997Co-Authors: Andreas Schramm, Lars Hauer Larsen, Niels Peter Revsbech, Rudolf AmannAbstract:Microelectrodes for O 2 and NO 2 − /NO 3 − and fluorescently labelled 16S rRNA-targeted oligonucleotide probes were combined to examine the activity and stratification of Nitrifying Bacteria in a trickling filter biofilm. Microprofiles showed that O 2 consumption and NO 3 − /NO 2 − production were restricted to the upper 50-100 μm of the biofilm. The vertical distribution of the Nitrifying Bacteria Nitrosomonas sp. and Nitrobacter sp. was investigated by fluorescent in situ hybridisation (FISH) with specific oligonucleotides. Nitrifiers formed a dense layer of cells and cell clusters in the upper part of the biofilm. This correlates well with the measured activity profiles. Ammonia- and nitrite-oxidisers occurred in close vicinity to each other supporting a fast sequential metabolism from ammonia to nitrate. Both species were not restricted to the oxic part of the biofilm, but also appeared -in lower numbers- in the anoxic layers on the bottom of the biofilm. A short term decrease in the O 2 concentration of the bulk water resulted in a quick decrease in O 2 penetration and metabolic rates inside the biofilm. However, neither the stratification nor the cellular ribosome content of nitrifiers changed within a few hours.
Satoshi Okabe - One of the best experts on this subject based on the ideXlab platform.
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population dynamics and in situ kinetics of Nitrifying Bacteria in autotrophic Nitrifying biofilms as determined by real time quantitative pcr
Biotechnology and Bioengineering, 2006Co-Authors: Tomonori Kindaichi, Yoshiko Kawano, Tsukasa Ito, Hisashi Satoh, Satoshi OkabeAbstract:Population dynamics of ammonia-oxidizing Bacteria (AOB) and uncultured Nitrospira-like nitrite-oxidizing Bacteria (NOB) dominated in autotrophic Nitrifying biofilms were determined by using real-time quantitative polymerase chain reaction (RTQ-PCR) and fluorescence in situ hybridization (FISH). Although two quantitative techniques gave the comparable results, the RTQ-PCR assay was easier and faster than the FISH technique for quantification of both Nitrifying Bacteria in dense microcolony-forming Nitrifying biofilms. Using this RTQ-PCR assay, we could successfully determine the maximum specific growth rate (µ = 0.021/h) of uncultured Nitrospira-like NOB in the suspended enrichment culture. The population dynamics of Nitrifying Bacteria in the biofilm revealed that once they formed the biofilm, the both Nitrifying Bacteria grew slower than in planktonic cultures. We also calculated the spatial distributions of average specific growth rates of both Nitrifying Bacteria in the biofilm based on the concentration profiles of NH, NO, and O2, which were determined by microelectrodes, and the double-Monod model. This simple model estimation could explain the stratified spatial distribution of AOB and Nitrospira-like NOB in the biofilm. The combination of culture-independent molecular techniques and microelectrode measurements is a very powerful approach to analyze the in situ kinetics and ecophysiology of Nitrifying Bacteria including uncultured Nitrospira-like NOB in complex biofilm communities. © 2006 Wiley Periodicals, Inc.
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fate of 14c labeled microbial products derived from Nitrifying Bacteria in autotrophic Nitrifying biofilms
Applied and Environmental Microbiology, 2005Co-Authors: Satoshi Okabe, Tomonori Kindaichi, Tsukasa ItoAbstract:The cross-feeding of microbial products derived from 14C-labeled Nitrifying Bacteria to heterotrophic Bacteria coexisting in an autotrophic Nitrifying biofilm was quantitatively analyzed by using microautoradiography combined with fluorescence in situ hybridization (MAR-FISH). After only Nitrifying Bacteria were labeled with [14C]bicarbonate, biofilm samples were incubated with and without NH4+ as a sole energy source for 10 days. The transfer of 14C originally incorporated into Nitrifying Bacterial cells to heterotrophic Bacteria was monitored with time by using MAR-FISH. The MAR-FISH analysis revealed that most phylogenetic groups of heterotrophic Bacteria except the beta-ProteoBacteria showed significant uptake of 14C-labeled microbial products. In particular, the members of the Chloroflexi were strongly MAR positive in the culture without NH4+ addition, in which Nitrifying Bacteria tended to decay. This indicated that the members of the Chloroflexi preferentially utilized microbial products derived from mainly biomass decay. On the other hand, the members of the Cytophaga-Flavobacterium cluster gradually utilized 14C-labeled products in the culture with NH4+ addition in which Nitrifying Bacteria grew. This result suggested that these Bacteria preferentially utilized substrate utilization-associated products of Nitrifying Bacteria and/or secondary metabolites of 14C-labeled structural cell components. Our results clearly demonstrated that the coexisting heterotrophic Bacteria efficiently degraded and utilized dead biomass and metabolites of Nitrifying Bacteria, which consequently prevented accumulation of organic waste products in the biofilm.
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ecophysiological interaction between Nitrifying Bacteria and heterotrophic Bacteria in autotrophic Nitrifying biofilms as determined by microautoradiography fluorescence in situ hybridization
Applied and Environmental Microbiology, 2004Co-Authors: Tomonori Kindaichi, Tsukasa Ito, Satoshi OkabeAbstract:Ecophysiological interactions between the community members (i.e., nitrifiers and heterotrophic Bacteria) in a carbon-limited autotrophic Nitrifying biofilm fed only NH4+ as an energy source were investigated by using a full-cycle 16S rRNA approach followed by microautoradiography (MAR)-fluorescence in situ hybridization (FISH). Phylogenetic differentiation (identification) of heterotrophic Bacteria was performed by 16S rRNA gene sequence analysis, and FISH probes were designed to determine the community structure and the spatial organization (i.e., niche differentiation) in the biofilm. FISH analysis showed that this autotrophic Nitrifying biofilm was composed of 50% Nitrifying Bacteria (ammonia-oxidizing Bacteria [AOB] and nitrite-oxidizing Bacteria [NOB]) and 50% heterotrophic Bacteria, and the distribution was as follows: members of the alpha subclass of the class ProteoBacteria (α-ProteoBacteria), 23%; γ-ProteoBacteria, 13%; green nonsulfur Bacteria (GNSB), 9%; Cytophaga-Flavobacterium-Bacteroides (CFB) division, 2%; and unidentified (organisms that could not be hybridized with any probe except EUB338), 3%. These results indicated that a pair of nitrifiers (AOB and NOB) supported a heterotrophic bacterium via production of soluble microbial products (SMP). MAR-FISH revealed that the heterotrophic Bacterial community was composed of Bacteria that were phylogenetically and metabolically diverse and to some extent metabolically redundant, which ensured the stability of the ecosystem as a biofilm. α- and γ-ProteoBacteria dominated the utilization of [14C]acetic acid and 14C-amino acids in this biofilm. Despite their low abundance (ca. 2%) in the biofilm community, members of the CFB cluster accounted for the largest fraction (ca. 64%) of the Bacterial community consuming N-acetyl-d-[1-14C]glucosamine (NAG). The GNSB accounted for 9% of the 14C-amino acid-consuming Bacteria and 27% of the [14C]NAG-consuming Bacteria but did not utilize [14C]acetic acid. Bacteria classified in the unidentified group accounted for 6% of the total heterotrophic Bacteria and could utilize all organic substrates, including NAG. This showed that there was an efficient food web (carbon metabolism) in the autotrophic Nitrifying biofilm community, which ensured maximum utilization of SMP produced by nitrifiers and prevented buildup of metabolites or waste materials of nitrifiers to significant levels.
V Hoang - One of the best experts on this subject based on the ideXlab platform.
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Nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
Water Research, 2014Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain StintziAbstract: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.
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Nitrifying moving bed biofilm reactor mbbr biofilm and biomass response to long term exposure to 1 c
Water Research, 2014Co-Authors: V Hoang, Robert Delatolla, Turki Abujamel, Walid Mottawea, Alain Gadbois, Edith Laflamme, Alain StintziAbstract: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.
Bruce E Rittmann - One of the best experts on this subject based on the ideXlab platform.
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Nitrifying biomass can retain its acclimation to 2 4 6 trichlorophenol
Water Research, 2020Co-Authors: Shasha Zou, Yongming Zhang, Fu Chen, Chenyuan Zhang, Bruce E RittmannAbstract:Abstract Many municipal wastewater treatment plants in China receive industrial wastewater that contains inhibitory organic chemicals, such as chlorinated phenols. For the common aerobic biological treatment, nitrification is a key step, but Nitrifying Bacteria are notably sensitive to inhibition by chlorinated phenols. In this work, normal activated sludge (containing Nitrifying biomass) was acclimated to 2,4,6-trichlorophenol (TCP). The acclimated biomass had more than 2-fold faster nitrification kinetics than normal biomass when exposed to TCP, and it also achieved effective TCP removal in parallel. When suddenly exposed to TCP after as much as two months without TCP input, the acclimated Nitrifying biomass retained effective nitrification and TCP biodegradation: The nitrification rate and TCP removal rate were 0.325 mM/h and 0.049 mM/h for the acclimated biomass, compared to only 0.165 mM/h and 0.001 mM/h for normal biomass. Resistance to TCP inhibition also was retained for 5 generations of sub-culturing without TCP exposure. High-throughput sequencing confirmed that the acclimated biomass contained Nitrifying Bacteria and heterotrophic Bacteria capable of degrading TCP, although the key genera changed during sub-culturing.
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diversity study of Nitrifying Bacteria in full scale municipal wastewater treatment plants
Water Research, 2007Co-Authors: Slil Siripong, Bruce E RittmannAbstract:We hypothesize that activated-sludge processes having stable and complete nitrification have significant and similar diversity and functional redundancy among its ammonia- and nitrite-oxidizing Bacteria, despite differences in temperature, solids retention time (SRT), and other operating conditions. To evaluate this hypothesis, we examined the diversity of Nitrifying Bacterial communities in all seven water-reclamation plants (WRPs) operated by Metropolitan Water Reclamation District of Greater Chicago (MWRDGC). These plants vary in types of influent waste stream, plant size, water temperature, and SRT. We used terminal restriction fragment length polymorphism (T-RFLP) targeting the 16S rRNA gene and group-specific ammonia-monooxygenase functional gene (amoA) to investigate these hard-to-culture Nitrifying Bacteria in the full-scale WRPs. We demonstrate that Nitrifying Bacteria carrying out the same metabolism coexist in all WRPs studied. We found ammonia-oxidizing Bacteria (AOB) belonging to the Nitrosomonas europaea/eutropha, Nitrosomonas oligotropha, Nitrosomonas communis, and Nitrosospira lineages in all plants. We also observed coexisting Nitrobacter and Nitrospira genera for nitrite-oxidizing Bacteria (NOB). Among the factors that varied among the WRPs, only the seasonal temperature variation seemed to change the Nitrifying community, especially the balance between Nitrosospira and Nitrosomonas, although both coexisted in winter and summer samples. The coexistence of various nitrifiers in all WRPs is evidence of functional redundancy, a feature that may help maintain the stability of the system for nitrification.
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dna microarray detection of Nitrifying Bacterial 16s rrna in wastewater treatment plant samples
Water Research, 2005Co-Authors: John J Kelly, Slil Siripong, Bruce E Rittmann, Hidetoshi Urakawa, John L Mccormack, Lori R Janus, Said El Fantroussi, Peter A Noble, Laura Sappelsa, David A StahlAbstract:A small scale DNA microarray containing a set of oligonucleotide probes targeting the 16S rRNAs of several groups of Nitrifying Bacteria was developed for the monitoring of wastewater treatment plant samples. The microarray was tested using reference rRNAs from pure cultures of Nitrifying Bacteria. Characterization of samples collected from an industrial wastewater treatment facility demonstrated that Nitrifying Bacteria could be detected directly by microarray hybridization without the need for PCR amplification. Specifically, the microarray detected Nitrosomonas spp. but did not detect Nitrobacter. The specificity and sensitivity of direct detection was evaluated using on-chip dissociation analysis, and by two independent analyses--an established membrane hybridization format and terminal restriction fragment length polymorphism fingerprinting (T-RFLP). The latter two analyses also revealed Nitrospira and Nitrobacter to be contributing populations in the treatment plant samples. The application of DNA microarrays to wastewater treatment systems, which has been demonstrated in the current work, should offer improved monitoring capabilities and process control for treatment systems, which are susceptible to periodic failures.
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dna microarray detection of Nitrifying Bacterial 16s rrna in wastewater treatment plant samples
Water Research, 2005Co-Authors: John J Kelly, Slil Siripong, Bruce E Rittmann, Hidetoshi Urakawa, John L Mccormack, Lori R Janus, Said El Fantroussi, Peter A Noble, Laura Sappelsa, David A StahlAbstract:A small scale DNA microarray containing a set of oligonucleotide probes targeting the 16S rRNAs of several groups of Nitrifying Bacteria was developed for the monitoring of wastewater treatment plant samples. The microarray was tested using reference rRNAs from pure cultures of Nitrifying Bacteria. Characterization of samples collected from an industrial wastewater treatment facility demonstrated that Nitrifying Bacteria could be detected directly by microarray hybridization without the need for PCR amplification. Specifically, the microarray detected Nitrosomonas spp. but did not detect Nitrobacter. The specificity and sensitivity of direct detection was evaluated using on-chip dissociation analysis, and by two independent analyses—an established membrane hybridization format and terminal restriction fragment length polymorphism fingerprinting (T-RFLP). The latter two analyses also revealed Nitrospira and Nitrobacter to be contributing populations in the treatment plant samples. The application of DNA microarrays to wastewater treatment systems, which has been demonstrated in the current work, should offer improved monitoring capabilities and process control for treatment systems, which are susceptible to periodic failures. r 2005 Elsevier Ltd. All rights reserved.