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Elahinik A, Li L, Pabst M, Abbas B, Xevgenos D, van Loosdrecht MCM, Pronk M. Aerobic granular sludge phosphate removal using glucose. WATER RESEARCH 2023; 247:120776. [PMID: 37898002 DOI: 10.1016/j.watres.2023.120776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/25/2023] [Accepted: 10/21/2023] [Indexed: 10/30/2023]
Abstract
Enhanced biological phosphate removal and aerobic sludge granulation are commonly studied with fatty acids as substrate. Fermentative substrates such as glucose have received limited attention. In this work, glucose conversion by aerobic granular sludge and its impact on phosphate removal was studied. Long-term stable phosphate removal and successful granulation were achieved. Glucose was rapidly taken up (273 mg/gVSS/h) at the start of the anaerobic phase, while phosphate was released during the full anaerobic phase. Some lactate was produced during glucose consumption, which was anaerobically consumed once glucose was depleted. The phosphate release appeared to be directly proportional to the uptake of lactate. The ratio of phosphorus released to glucose carbon taken up over the full anaerobic phase was 0.25 Pmol/Cmol. Along with glucose and lactate uptake in the anaerobic phase, poly‑hydroxy-alkanoates and glycogen storage were observed. There was a linear correlation between glucose consumption and lactate formation. While lactate accounted for approximately 89 % of the observed products in the bulk liquid, minor quantities of formate (5 %), propionate (4 %), and acetate (3 %) were also detected (mass fraction). Formate was not consumed anaerobically. Quantitative fluorescence in-situ hybridization (qFISH) revealed that polyphosphate accumulating organisms (PAO) accounted for 61 ± 15 % of the total biovolume. Metagenome evaluation of the biomass indicated a high abundance of Micropruina and Ca. Accumulibacter in the system, which was in accordance with the microscopic observations and the protein mass fraction from metaproteome analysis. Anaerobic conversions were evaluated based on theoretical ATP balances to provide the substrate distribution amongst the dominant genera. This research shows that aerobic granular sludge technology can be applied to glucose-containing effluents and that glucose is a suitable substrate for achieving phosphate removal. The results also show that for fermentable substrates a microbial community consisting of fermentative organisms and PAO develop.
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Affiliation(s)
- Ali Elahinik
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629HZ, the Netherlands.
| | - Linghang Li
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629HZ, the Netherlands
| | - Martin Pabst
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629HZ, the Netherlands
| | - Ben Abbas
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629HZ, the Netherlands
| | - Dimitrios Xevgenos
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629HZ, the Netherlands
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629HZ, the Netherlands
| | - Mario Pronk
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629HZ, the Netherlands; Royal HaskoningDHV, Laan 1914 no 35, Amersfoort 3800AL, the Netherlands
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Maszenan AM, Bessarab I, Williams RBH, Petrovski S, Seviour RJ. The phylogeny, ecology and ecophysiology of the glycogen accumulating organism (GAO) Defluviicoccus in wastewater treatment plants. WATER RESEARCH 2022; 221:118729. [PMID: 35714465 DOI: 10.1016/j.watres.2022.118729] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/22/2022] [Accepted: 06/08/2022] [Indexed: 06/15/2023]
Abstract
This comprehensive review looks critically what is known about members of the genus Defluviicoccus, an example of a glycogen accumulating organism (GAO), in wastewater treatment plants, but found also in other habitats. It considers the operating conditions thought to affect its performance in activated sludge plants designed to remove phosphorus microbiologically, including the still controversial view that it competes with the polyphosphate accumulating bacterium Ca. Accumulibacter for readily biodegradable substrates in the anaerobic zone receiving the influent raw sewage. It looks at its present phylogeny and what is known about it's physiology and biochemistry under the highly selective conditions of these plants, where the biomass is recycled continuously through alternative anaerobic (feed); aerobic (famine) conditions encountered there. The impact of whole genome sequence data, which have revealed considerable intra- and interclade genotypic diversity, on our understanding of its in situ behaviour is also addressed. Particular attention is paid to the problems in much of the literature data based on clone library and next generation DNA sequencing data, where Defluviicoccus identification is restricted to genus level only. Equally problematic, in many publications no attempt has been made to distinguish between Defluviicoccus and the other known GAO, especially Ca. Competibacter, which, as shown here, has a very different ecophysiology. The impact this has had and continues to have on our understanding of members of this genus is discussed, as is the present controversy over its taxonomy. It also suggests where research should be directed to answer some of the important research questions raised in this review.
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Affiliation(s)
- Abdul M Maszenan
- E2S2, NUS Environmental Research Institute, National University of Singapore, 117411, Singapore
| | - Irina Bessarab
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, 117456, Singapore
| | - Rohan B H Williams
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, 117456, Singapore
| | - Steve Petrovski
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, 3086 Victoria, Australia
| | - Robert J Seviour
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, 3086 Victoria, Australia.
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3
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Chen J, Wang J, Wang X, Lv Y, Li D, Hou J, He X. Strengthening anoxic glycogen consumption in SNEDPR-CW as a strategy to control PAO-GAO competition under carbon limited condition. CHEMOSPHERE 2022; 288:132617. [PMID: 34678339 DOI: 10.1016/j.chemosphere.2021.132617] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/04/2021] [Accepted: 10/18/2021] [Indexed: 06/13/2023]
Abstract
Cooperation between Phosphate and Glycogen Accumulating Organisms (PAOs and GAOs) plays a pivotal role in nutrients removal in simultaneous nitrification endogenous denitrification and phosphorous removal (SNEDPR) systems. Recent findings have expanded the application of SNEDPR from activated sludge system to constructed wetland (CW). However, how to regulate competition between PAOs and GAOs in SNEDPR-based CW is still unclear. Here we showed that, GAOs could easily gain dominance over PAOs in SNEDPR-CW under alternating anaerobic/aerobic (A/O) operational mode. Shortening aerobic hydraulic retention time (HRT) at low oxygen concentration was benefit for simultaneous nitrification endogenous denitrification (SNED) and denitrifying dephosphatation but would reduce the overall phosphorus uptake rate and lead to high phosphorus effluent concentrations. Extended aerobic HRT promoted the proliferation of aerobic GAOs over PAOs, decreasing both enhanced biological phosphorus removal (EBPR) and SNED performance. Surprisingly, by switching the operation of system to alternating anaerobic/aerobic/anoxic (A/O/A) mode, an extraordinary nutrients removal performance with mean nitrogen and phosphorus removal efficiency of 84.57% and 89.37% was achieved under carbon sources limited condition. Stoichiometric analysis demonstrated that adding anoxic stage strengthened the intracellular glycogen oxidization of GAOs for denitrification which compromised its subsequent anaerobic carbon sources uptake and PHA storage and provided sufficient carbon sources for PAOs. Microbial community analysis showed that numerical ratio of GAOs to PAOs decreased from 6.67 under A/O to 4.89 under A/O/A mode, which further indicated strengthening glycogen denitrification of GAOs should be an effective way to regulate microbial competition in order to obtain a desired nutrients removal performance in SNEDPR-CW.
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Affiliation(s)
- Jieyu Chen
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jie Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xiaoning Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yabing Lv
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Dapeng Li
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China
| | - Jie Hou
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China.
| | - Xugang He
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China.
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Moreno-Andrade I, Valdez-Vazquez I, López-Rodríguez A. Effect of transient pH variation on microbial activity and physical characteristics of aerobic granules treating 4-chlorophenol. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2020; 55:878-885. [PMID: 32275179 DOI: 10.1080/10934529.2020.1751505] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/26/2020] [Accepted: 03/27/2020] [Indexed: 06/11/2023]
Abstract
Chlorophenols are inhibitory compounds that can be biodegraded by aerobic granules in discontinuous processes. Many industrial wastewaters are characterized by transient pH variation over time. These pH changes could affect the overall granule structure and microbial activity during the chlorophenol biodegradation. The objective of this research was to evaluate the effects of transient pH variation on the specific degradation rate (q), granule integrity coefficient (IC), and size in sequencing batch reactors treating 4-chlorophenol (4-CP). First, aerobic granules were acclimated for efficient 4-CP degradation (>99%). The acclimated granules consisted of 55.7% of the phyla Proteobacteria and 40.6% of Bacteroidetes. The main bacteria belong to the order Sphingobacteriales (24%), as well as Amaricoccus, Acidovorax, Shinella, Rhizobium, and Flavobacterium, some of which are new genera reported in acclimated granules degrading 4-CP. Then, pH changes were applied to the acclimated aerobic granules, observing that acid pHs decreased to a greater extent the specific degradation rate (67% to 99%) than basic pHs (34% to 80%). These pH changes caused the granule disaggregation but with lower effects on the IC. The effects of pH change were mainly on the microbial activity more than the physical characteristics of aerobic granules degrading 4-CP.
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Affiliation(s)
- Iván Moreno-Andrade
- Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Querétaro, Mexico
| | - Idania Valdez-Vazquez
- Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Querétaro, Mexico
| | - Antonio López-Rodríguez
- Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Querétaro, Mexico
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Tang W, Li X, Liu H, Wu S, Zhou Q, Du C, Teng Q, Zhong Y, Yang C. Sequential vertical flow trickling filter and horizontal flow multi-soil-layering reactor for treatment of decentralized domestic wastewater with sodium dodecyl benzene sulfonate. BIORESOURCE TECHNOLOGY 2020; 300:122634. [PMID: 31901779 DOI: 10.1016/j.biortech.2019.122634] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/12/2019] [Accepted: 12/15/2019] [Indexed: 05/23/2023]
Abstract
Sequential vertical flow trickling filter and horizontal flow multi-soil-layering bioreactor were investigated for the treatment of decentralized domestic wastewater at various concentrations of sodium dodecyl benzene sulfonate (SDBS). Results have shown that the removal rate of COD could reach 92.1% at initial COD concentration of 960 mg/L (800 mg/L was provided by SDBS). NH4+-N concentration could be reduced from 52.4 to 9.71 mg/L without aeration. Besides, a quadratic function model was fit to describe the relationship between the relative activity of amylase and the protein content in extracellular polymer substance. SDBS could inhibit the transport and metabolisms of amino acids, lipids and carbohydrates in biofilms. The analysis of three-dimensional fluorescence diagram indicated that the peak in excitation/emission wavelengths = 310-340/370-430 nm was the characteristic peaks of some active substances such as some enzymes in EPS. Only Microbacterium could totally offset the toxicity of SDBS degradation products.
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Affiliation(s)
- Wenchang Tang
- College of Environmental Science and Engineering, Hunan University, and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China; Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China
| | - Xiang Li
- College of Environmental Science and Engineering, Hunan University, and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Haiyang Liu
- Datang Environment Industry Group Co., Ltd. Beijing 100097, China
| | - Shaohua Wu
- College of Environmental Science and Engineering, Hunan University, and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Qi Zhou
- College of Environmental Science and Engineering, Hunan University, and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Cheng Du
- Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China
| | - Qing Teng
- Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China
| | - Yuanyuan Zhong
- Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China
| | - Chunping Yang
- College of Environmental Science and Engineering, Hunan University, and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China; Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China; Hunan Provincial Environmental Protection Engineering Center for Organic Pollution Control of Urban Water and Wastewater, Changsha, Hunan 410001, China.
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6
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Stokholm-Bjerregaard M, McIlroy SJ, Nierychlo M, Karst SM, Albertsen M, Nielsen PH. A Critical Assessment of the Microorganisms Proposed to be Important to Enhanced Biological Phosphorus Removal in Full-Scale Wastewater Treatment Systems. Front Microbiol 2017; 8:718. [PMID: 28496434 PMCID: PMC5406452 DOI: 10.3389/fmicb.2017.00718] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 04/06/2017] [Indexed: 11/13/2022] Open
Abstract
Understanding the microbiology of phosphorus (P) removal is considered essential to knowledge-based optimization of enhanced biological P removal (EBPR) systems. Biological P removal is achieved in these systems by promoting the growth of organisms collectively known as the polyphosphate accumulating organisms (PAOs). Also considered important to EBPR are the glycogen accumulating organisms (GAOs), which are theorized to compete with the PAOs for resources at the expense of P removal efficiency. Numerous studies have sought to identify the PAOs and their GAOs competitors, with several candidates proposed for each over the last few decades. The current study collectively assessed the abundance and diversity of all proposed PAOs and GAOs in 18 Danish full-scale wastewater treatment plants with well-working biological nutrient removal over a period of 9 years using 16S rRNA gene amplicon sequencing. The microbial community structure in all plants was relatively stable over time. Evidence for the role of the proposed PAOs and GAOs in EBPR varies and is critically assessed, in light of their calculated amplicon abundances, to indicate which of these are important in full-scale systems. Bacteria from the genus Tetrasphaera were the most abundant of the PAOs. The “Candidatus Accumulibacter” PAOs were in much lower abundance and appear to be biased by the amplicon-based method applied. The genera Dechloromonas, Microlunatus, and Tessaracoccus were identified as abundant putative PAO that require further research attention. Interestingly, the actinobacterial Micropruina and sbr-gs28 phylotypes were among the most abundant of the putative GAOs. Members of the genera Defluviicoccus, Propionivibrio, the family Competibacteraceae, and the spb280 group were also relatively abundant in some plants. Despite observed high abundances of GAOs (periodically exceeding 20% of the amplicon reads), P removal performance was maintained, indicating that these organisms were not outcompeting the PAOs in these EBPR systems. Phylogenetic diversity within each of the PAOs and GAOs genera was observed, which is consistent with reported metabolic diversity for these. Whether or not key traits can be assigned to sub-genus level clades requires further investigation.
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Affiliation(s)
- Mikkel Stokholm-Bjerregaard
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
| | - Simon J McIlroy
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
| | - Marta Nierychlo
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
| | - Søren M Karst
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
| | - Mads Albertsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
| | - Per H Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark
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Guo X, Liu J, Xiao B. Evaluation of the damage of cell wall and cell membrane for various extracellular polymeric substance extractions of activated sludge. J Biotechnol 2014; 188:130-5. [PMID: 25173614 DOI: 10.1016/j.jbiotec.2014.08.025] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 08/18/2014] [Accepted: 08/19/2014] [Indexed: 10/24/2022]
Abstract
Extracellular polymeric substances (EPS) are susceptible to contamination by intracellular substances released during the extraction of EPS owing to the damage caused to microbial cell structures. The damage to cell walls and cell membranes in nine EPS extraction processes of activated sludge was evaluated in this study. The extraction of EPS (including proteins, carbohydrates and DNA) was the highest using the NaOH extraction method and the lowest using formaldehyde extraction. All nine EPS extraction methods in this study resulted in cell wall and membrane damage. The damage to cell walls, evaluated by 2-keto-3-deoxyoctonate (KDO) and N-acetylglucosamine content changes in extracted EPS, was the most significant in the NaOH extraction process. Formaldehyde extraction showed a similar extent of damage to cell walls to those detected in the control method (centrifugation), while those in the formaldehyde-NaOH and cation exchange resin extractions were slightly higher than those detected in the control. N-acetylglucosamine was more suitable than KDO for the evaluation of cell wall damage in the EPS extraction of activated sludge. The damage to cell membranes was characterized by two fluorochromes (propidium iodide and FITC Annexin V) with flow cytometry (FCM) measurement. The highest proportion of membrane-damaged cells was detected in NaOH extraction (26.54% of total cells) while membrane-damaged cells comprised 8.19% of total cells in the control.
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Affiliation(s)
- Xuesong Guo
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Junxin Liu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Benyi Xiao
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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McIlroy SJ, Speirs LBM, Tucci J, Seviour RJ. In situ profiling of microbial communities in full-scale aerobic sequencing batch reactors treating winery waste in australia. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:8794-8803. [PMID: 21875070 DOI: 10.1021/es2018576] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
On-site aerobic sequencing batch reactor (SBR) treatment plants are implemented in many Australian wineries to treat the large volumes of associated wastewater they generate. Yet very little is known about their microbiology. This paper represents the first attempt to analyze the communities of three such systems sampled during both vintage and nonvintage operational periods using molecular methods. Alphaproteobacterial tetrad forming organisms (TFO) related to members of the genus Defluviicoccus and Amaricoccus dominated all three systems in both operational periods. Candidatus 'Alysiosphaera europaea' and Zoogloea were codominant in two communities. Production of high levels of exocellular capsular material by Zoogloea and Amaricoccus is thought to explain the poor settleability of solids in one of these plants. The dominance of these organisms is thought to result from the high COD to N/P ratios that characterize winery wastes, and it is suggested that manipulating this ratio with nutrient dosing may help control the problems they cause.
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Affiliation(s)
- Simon J McIlroy
- Biotechnology Research Centre, Department of Pharmacy and Applied Science, La Trobe University, Bendigo, Victoria, Australia
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Kiss B, Bakos V, Liu WT, Jobbágy A. Full-scale use of glycogen-accumulating organisms for excess biological carbon removal. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2011; 83:855-864. [PMID: 22073733 DOI: 10.2175/106143010x12851009156844] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The purpose of this study has been to verify the efficient full-scale applicability of glycogen-accumulating organisms (GAOs) for excess biological carbon removal, that is, for removing more carbon substrate than the amount of available nutrients would allow in the conventional activated sludge process of microbial growth. This aims to cost-effectively overcome the problem of viscous bulking occurring in a fully aerated system, with nutrient deficiency. Analytical data measured at the wastewater treatment plant of the Balatonboglár (BB) winery in Balatonboglár, Hungary, containing consecutive unaerated and aerated activated sludge basins, reflected a high performance with efficient carbon removal and good sludge settling, without dosing any external nutrient source to the severely nitrogen- and phosphorous-deficient influent. Supplementary laboratory-scale batch experiments and microbiological tests verified the abundance of GAOs in the activated sludge system and elucidated their role in efficient excess biological carbon removal.
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Affiliation(s)
- Bernadett Kiss
- Department of Applied Biotechnology and Food Science, Budapest University of Technology and Economics, Budapest, Hungary
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10
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Microbial community engineering for biopolymer production from glycerol. Appl Microbiol Biotechnol 2011; 92:631-9. [DOI: 10.1007/s00253-011-3359-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 04/30/2011] [Accepted: 05/01/2011] [Indexed: 10/18/2022]
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11
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Yan ST, Chu LB, Xing XH, Yu AF, Sun XL, Jurcik B. Analysis of the mechanism of sludge ozonation by a combination of biological and chemical approaches. WATER RESEARCH 2009; 43:195-203. [PMID: 18976790 DOI: 10.1016/j.watres.2008.09.039] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Revised: 09/30/2008] [Accepted: 09/30/2008] [Indexed: 05/27/2023]
Abstract
Using the practical sludge obtained from municipal sewage treatment plants, the mechanism of the sludge ozonation process was systematically investigated by a combination of biological and chemical approaches, including analysis of the changes in biological response by CFU and PCR-DGGE, bio-macromolecular activity and radical scavenging activity. The results indicated that after the sludge was exposed to ozone at less than 0.02 g O(3)/g TSS, the DGGE fingerprint remained constant and there was still some enzyme activity, indicating that the sludge solubilization was the main process. At greater than 0.02 g O(3)/g TSS, the bacteria began to be broken down and ozone was used to oxidize the bio-macromolecules such as proteins and DNA released from the sludge. Bacteria belonging to 'G-Bacteria' were able to conserve their DNA in the presence of less than 0.08 g O(3)/g TSS. At levels higher than 0.10 g O(3)/g TSS, the disintegration of the sludge matrix became slow and the microbes lost most of their activity, and ozone was used to transform the bio-macromolecules into small molecules. However, at levels higher than 0.14 g O(3)/g TSS, the ozone failed to oxidize the sludge efficiently, because several radical scavengers such as lactic acid and SO(4)(2-) were released from the microbial cells in the sludge.
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Affiliation(s)
- Sang-Tian Yan
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
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12
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Gu AZ, Saunders A, Neethling JB, Stensel HD, Blackall LL. Functionally relevant microorganisms to enhanced biological phosphorus removal performance at full-scale wastewater treatment plants in the United States. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2008; 80:688-698. [PMID: 18751532 DOI: 10.2175/106143008x276741] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The abundance and relevance ofAccumulibacter phosphatis (presumed to be polyphosphate-accumulating organisms [PAOs]), Competibacter phosphatis (presumed to be glycogen-accumulating organisms [GAOs]), and tetrad-forming organisms (TFOs) to phosphorus removal performance at six full-scale enhanced biological phosphorus removal (EBPR) wastewater treatment plants were investigated. Coexistence of various levels of candidate PAOs and GAOs were found at these facilities. Accumulibacter were found to be 5 to 20% of the total bacterial population, and Competibacter were 0 to 20% of the total bacteria population. The TFO abundance varied from nondetectable to dominant. Anaerobic phosphorus (P) release to acetate uptake ratios (P(rel)/HAc(up)) obtained from bench tests were correlated positively with the abundance ratio of Accumulibacter/(Competibacter +TFOs) and negatively with the abundance of (Competibacter +TFOs) for all plants except one, suggesting the relevance of these candidate organisms to EBPR processes. However, effluent phosphorus concentration, amount of phosphorus removed, and process stability in an EBPR system were not directly related to high PAO abundance or mutually exclusive with a high GAO fraction. The plant that had the lowest average effluent phosphorus and highest stability rating had the lowest P(rel)/HAc(up) and the most TFOs. Evaluation of full-scale EBPR performance data indicated that low effluent phosphorus concentration and high process stability are positively correlated with the influent readily biodegradable chemical oxygen demand-to-phosphorus ratio. A system-level carbon-distribution-based conceptual model is proposed for capturing the dynamic competition between PAOs and GAOs and their effect on an EBPR process, and the results from this study seem to support the model hypothesis.
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Affiliation(s)
- April Z Gu
- Department of Civil and Environmental Engineering, Northeastern University, Boston, Massachusetts, USA.
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13
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Ahn CH, Park HD, Lee YO, Park JK. Appearance of novel G-bacteria belonging to acidobacteria in a dairy wastewater treatment plant. ENVIRONMENTAL TECHNOLOGY 2008; 29:497-504. [PMID: 18661733 DOI: 10.1080/09593330801984530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A dairy wastewater treatment plant operates a sequencing batch reactor (SBR) and stimulates enhanced biological phosphorus removal (EBPR) process with alternating anaerobic and aerobic cycles. Occasionally, the plant suffers from a high suspended solids problem in the supernatant. Interestingly, the occurrence of high suspended solids coincided with times when the EBPR process failed to remove phosphorus. To find out if there was a relationship between the EBPR failure and the high suspended solids problem, effluent samples were collected from the site during the period of poor phosphorus removal and examined microscopically. It was found that cocci-shaped bacteria (3-4 microm in diameter) were abundant in the effluent samples and they were clustered in tetrads. These were believed to be G-bacteria and results of both Gram and Neisser staining tests were negative, suggesting that they had few intracellular polyphosphate granules. Using polymerase chain reaction (PCR), cloning and deoxyribonucleic acid (DNA) sequence analysis, the phylogenetic information of in situ G-bacteria was obtained. It was found that all of the recovered clones were clustered in the phylum of Acidobacteria.
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MESH Headings
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Dairying
- Microscopy, Electron, Scanning
- Microscopy, Phase-Contrast
- Phosphorus/metabolism
- Phylogeny
- Polymerase Chain Reaction
- Proteobacteria/genetics
- Proteobacteria/growth & development
- Proteobacteria/isolation & purification
- Proteobacteria/metabolism
- RNA, Ribosomal, 16S/chemistry
- RNA, Ribosomal, 16S/genetics
- Waste Disposal, Fluid/methods
- Water Pollutants, Chemical/metabolism
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Affiliation(s)
- C H Ahn
- Department of Civil and Environmental Engineering, University of Wisconsin, Madison, Wisconsin, 53706, USA
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14
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Wilmes P, Wexler M, Bond PL. Metaproteomics provides functional insight into activated sludge wastewater treatment. PLoS One 2008; 3:e1778. [PMID: 18392150 PMCID: PMC2289847 DOI: 10.1371/journal.pone.0001778] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Accepted: 01/31/2008] [Indexed: 11/21/2022] Open
Abstract
Background Through identification of highly expressed proteins from a mixed culture activated sludge system this study provides functional evidence of microbial transformations important for enhanced biological phosphorus removal (EBPR). Methodology/Principal Findings A laboratory-scale sequencing batch reactor was successfully operated for different levels of EBPR, removing around 25, 40 and 55 mg/l P. The microbial communities were dominated by the uncultured polyphosphate-accumulating organism “Candidatus Accumulibacter phosphatis”. When EBPR failed, the sludge was dominated by tetrad-forming α-Proteobacteria. Representative and reproducible 2D gel protein separations were obtained for all sludge samples. 638 protein spots were matched across gels generated from the phosphate removing sludges. 111 of these were excised and 46 proteins were identified using recently available sludge metagenomic sequences. Many of these closely match proteins from “Candidatus Accumulibacter phosphatis” and could be directly linked to the EBPR process. They included enzymes involved in energy generation, polyhydroxyalkanoate synthesis, glycolysis, gluconeogenesis, glycogen synthesis, glyoxylate/TCA cycle, fatty acid β oxidation, fatty acid synthesis and phosphate transport. Several proteins involved in cellular stress response were detected. Conclusions/Significance Importantly, this study provides direct evidence linking the metabolic activities of “Accumulibacter” to the chemical transformations observed in EBPR. Finally, the results are discussed in relation to current EBPR metabolic models.
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Affiliation(s)
- Paul Wilmes
- School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
| | - Margaret Wexler
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Philip L. Bond
- School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
- * E-mail:
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15
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Ecophysiology of the Actinobacteria in activated sludge systems. Antonie van Leeuwenhoek 2008; 94:21-33. [DOI: 10.1007/s10482-008-9226-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Accepted: 02/01/2008] [Indexed: 10/22/2022]
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16
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Montoya T, Borrás L, Aguado D, Ferrer J, Seco A. Detection and prevention of enhanced biological phosphorus removal deterioration caused by Zoogloea overabundance. ENVIRONMENTAL TECHNOLOGY 2008; 29:35-42. [PMID: 18610543 DOI: 10.1080/09593330802008560] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A sequencing batch reactor was operated in the conventional anaerobic-aerobic mode for enhanced biological phosphorus removal using acetate as the sole substrate. Despite the nutrients concentrations in the influent being high enough to satisfy the biological requirements, Zoogloea ramigera managed to grow in the system until it had negative effects on the process performance. The excess of exocellular polymeric material produced by this microorganism contributed to a viscous bulking phenomenon and caused important settling problems. The examination of the sludge under the microscope was a valuable tool to diagnose the cause of the imbalance in the process. The strategy adopted to avoid the deterioration of the process (changing key operational factors affecting the Z. ramigera development) allowed the successful recovery the enhanced biological phosphorus removal system. The effectiveness of this approach was confirmed by analyzing several parameters along the operational period (SVI, Y(PO4), TSS, %VSS...) together with microbiological examinations of the sludge.
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Affiliation(s)
- T Montoya
- Dpto Ingeniería Hidráulica y Medio Ambiente, Universidad Politécnica de Valencia, Camino de Vera s/n. 46022 Valencia, Valencia, Spain
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17
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Yan S, Subramanian B, Surampalli RY, Narasiah S, Tyagi RD. Isolation, Characterization, and Identification of Bacteria from Activated Sludge and Soluble Microbial Products in Wastewater Treatment Systems. ACTA ACUST UNITED AC 2007. [DOI: 10.1061/(asce)1090-025x(2007)11:4(240)] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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18
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Kondo T, Ebie Y, Tsuneda S, Inamori Y. Detection of Defluvicoccus-related Glycogen-accumulating Organisms in Enhanced Biological Phosphorus Removal Processes. Microbes Environ 2007. [DOI: 10.1264/jsme2.22.190] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Takashi Kondo
- Department of Chemical Engineering, Waseda University
| | - Yoshitaka Ebie
- Research Center for Material Cycles and Waste Management, National Institute for Environmental Studies
| | | | - Yuhei Inamori
- Research Center for Material Cycles and Waste Management, National Institute for Environmental Studies
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19
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Burow LC, Kong Y, Nielsen JL, Blackall LL, Nielsen PH. Abundance and ecophysiology of Defluviicoccus spp., glycogen-accumulating organisms in full-scale wastewater treatment processes. Microbiology (Reading) 2007; 153:178-85. [PMID: 17185546 DOI: 10.1099/mic.0.2006/001032-0] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The activity of glycogen-accumulating organisms (GAOs) in enhanced biological phosphorus removal (EBPR) wastewater treatment plants has been proposed as one cause of deterioration of EBPR. Putative GAOs from the Alphaproteobacteria, Defluviicoccus spp. (including D. vanus), were studied in full-scale EBPR plants to determine their distribution, abundance and ecophysiology. Fluorescence in situ hybridization (FISH) demonstrated that Defluviicoccus spp. were generally low in abundance; however, in one plant surveyed, Cluster 2 Defluviicoccus constituted 9 % of all Bacteria. FISH combined with microautoradiography revealed that both Cluster 1 and Cluster 2 Defluviicoccus were capable of taking up a narrow range of substrates including acetate, propionate, pyruvate and glucose under anaerobic and aerobic conditions. Formate, butyrate, ethanol and several other substrates were not taken up. Cluster 2 Defluviicoccus demonstrated a phenotype consistent with the current metabolic model for GAOs--anaerobic assimilation of acetate and reduction to polyhydroxyalkanoates (PHA) using the glycolytic pathway, and aerobic consumption of PHA. Polyphosphate-accumulating organisms (PAOs, 'Candidatus Accumulibacter phosphatis') and other putative GAOs ('Candidatus Competibacter phosphatis') co-existed in two plants with Cluster 2 Defluviicoccus, but in both plants, the latter organisms were more abundant. Thus Cluster 2 Defluviicoccus can be relatively abundant and could be carbon competitors of PAOs and other GAOs in EBPR plants.
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Affiliation(s)
- Luke C Burow
- Advanced Wastewater Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
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20
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McKenzie CM, Seviour EM, Schumann P, Maszenan AM, Liu JR, Webb RI, Monis P, Saint CP, Steiner U, Seviour RJ. Isolates of ‘Candidatus Nostocoida limicola’ Blackall et al. 2000 should be described as three novel species of the genus Tetrasphaera, as Tetrasphaera jenkinsii sp. nov., Tetrasphaera vanveenii sp. nov. and Tetrasphaera veronensis sp. nov. Int J Syst Evol Microbiol 2006; 56:2279-2290. [PMID: 17012548 DOI: 10.1099/ijs.0.63978-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Despite differences in their morphologies, comparative analyses of 16S rRNA gene sequences revealed high levels of similarity (>94 %) between strains of the filamentous bacterium ‘Candidatus Nostocoida limicola’ and the cocci Tetrasphaera australiensis and Tetrasphaera japonica and the rod Tetrasphaera elongata, all isolated from activated sludge. These sequence data and their chemotaxonomic characters, including cell wall, menaquinone and lipid compositions and fingerprints of their 16S–23S rRNA intergenic regions, support the proposition that these isolates should be combined into a single genus containing six species, in the family Intrasporangiaceae in the Actinobacteria. This suggestion receives additional support from DNA–DNA hybridization data and when partial sequences of the rpoC1 gene are compared between these strains. Even though few phenotypic characterization data were obtained for these slowly growing isolates, it is proposed, on the basis of the extensive chemotaxonomic and molecular evidence presented here, that ‘Candidatus N. limicola’ strains Ben 17, Ben 18, Ben 67, Ben 68 and Ben 74 all be placed into the species Tetrasphaera jenkinsii sp. nov. (type strain Ben 74T=DSM 17519T=NCIMB 14128T), ‘Candidatus N. limicola’ strain Ben 70 into Tetrasphaera vanveenii sp. nov. (type strain Ben 70T=DSM 17518T=NCIMB 14127T) and ‘Candidatus N. limicola’ strains Ver 1 and Ver 2 into Tetrasphaera veronensis sp. nov. (type strain Ver 1T=DSM 17520T=NCIMB 14129T).
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Affiliation(s)
- C M McKenzie
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
| | - E M Seviour
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
| | - P Schumann
- DSMZ - Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Mascheroder Weg 1b, D-38124 Braunschweig, Germany
| | - A M Maszenan
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
| | - J-R Liu
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
| | - R I Webb
- Centre for Microscopy and Microanalysis, Department of Microbiology, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - P Monis
- Australian Water Quality Centre, Bolivar, South Australia 5108, Australia
| | - C P Saint
- Australian Water Quality Centre, Bolivar, South Australia 5108, Australia
| | - U Steiner
- DSMZ - Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Mascheroder Weg 1b, D-38124 Braunschweig, Germany
| | - R J Seviour
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
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21
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Whang LM, Park JK. Competition between polyphosphate- and glycogen-accumulating organisms in enhanced-biological-phosphorus-removal systems: effect of temperature and sludge age. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2006; 78:4-11. [PMID: 16553160 DOI: 10.2175/106143005x84459] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Temperature and sludge age were found to be important factors in determining the outcome of competition between polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating non-polyphosphate organisms (GAOs) and the resultant stability of enhanced-biological-phosphorus removal (EBPR). At 20 degrees C and a 10-day sludge age, PAOs were dominant in an anaerobic/aerobic (A/O) sequencing-batch reactor (SBR), as a result of their higher anaerobic-acetate-uptake rate and aerobic-biomass yield than GAOs. However, at 30 degrees C and a 10-day sludge age, GAOs were able to outcompete PAOs in the A/O SBR because of their higher anaerobic-acetate-uptake rate than PAOs. At 30 degrees C and a 5-day sludge age, GAOs coexisted with PAOs in the A/O SBR, resulting in unstable EBPR performance. At 30 degrees C, reducing the sludge age from 5 to 3 days improved the EBPR efficiency drastically, and the EBPR performance was stable. The maximum specific-anaerobic-acetate-uptake rates of GAO-enriched sludge were affected by temperature with the Arrhenius temperature coefficient theta of 0.042 (degrees C(-1) between 10 and 30 degrees C. The effect of sludge age (5 and 10 days) on the maximum specific-anaerobic-acetate-uptake rates of GAO-enriched activated sludge, however, was not significant. For the PAO-enriched activated sludge, the maximum specific-anaerobic-acetate-uptake rate did not change significantly between 20 and 30 degrees C, but significantly increased from 0.38 to 0.52 mmol-C/ mmol-C/h as the sludge age decreased from 10 to 3 days at 30 degrees C.
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22
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Maszenan AM, Seviour RJ, Patel BKC, Janssen PH, Wanner J. Defluvicoccus vanus gen. nov., sp. nov., a novel Gram-negative coccus/coccobacillus in the 'Alphaproteobacteria' from activated sludge. Int J Syst Evol Microbiol 2005; 55:2105-2111. [PMID: 16166717 DOI: 10.1099/ijs.0.02332-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A novel Gram-negative coccus/coccobacillus, strain Ben 114(T), growing in tetrads, clusters or aggregates, was isolated from activated sludge by micromanipulation. 16S rRNA gene sequence analysis revealed that it belonged to the 'Alphaproteobacteria', with no close relatives among cultured bacterial isolates. On the basis of phylogenetic data, this organism is considered to belong to a new genus, Defluvicoccus, represented by the species Defluvicoccus vanus sp. nov., a name chosen because of the distinctive staining properties of this organism; only the cell wall stained strongly with a wide range of stains, giving the cell a hollow and empty appearance. No intracellular polyphosphate granules could be detected after staining, but poly-beta-hydroxyalkanoate inclusions were detected using Nile blue A staining. Because of its taxonomic distance from its closest relatives among the 'Alphaproteobacteria', namely members of the genera Azospirillum, Phaeospirillum, Rhodospirillum, Rhodocista, Magnetospirillum and Rhodospira, D. vanus is considered to represent a new phylogenetic lineage within subgroup 1 of the 'Alphaproteobacteria', the D. vanus subgroup. The type strain is Ben 114(T) (=NCIMB 13612(T)=CIP 107350(T)).
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Affiliation(s)
- A M Maszenan
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3550, Australia
| | - R J Seviour
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3550, Australia
| | - B K C Patel
- School of Biological and Biomedical Sciences, Faculty of Science and Technology, Griffith University, Nathan, Queensland 4111, Australia
| | - P H Janssen
- Department of Microbiology and Immunology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - J Wanner
- Department of Water Technology and Environmental Engineering, Prague Institute of Chemical Technology, Praha 6, Czech Republic
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23
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Maszenan AM, Tay JH, Schumann P, Jiang HL, Tay STL. Quadrisphaera granulorum gen. nov., sp. nov., a Gram-positive polyphosphate-accumulating coccus in tetrads or aggregates isolated from aerobic granules. Int J Syst Evol Microbiol 2005; 55:1771-1777. [PMID: 16166665 DOI: 10.1099/ijs.0.63583-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A Gram-positive bacterium, designated strain AG019T, was isolated by micromanipulation from aerobic granules obtained from a laboratory-scale sequencing batch reactor. This isolate grew axenically as cocci clustered predominantly in tetrads, and was morphologically similar to the dominant organisms observed in the biomass. The morphology also resembled that of the tetrad-forming organisms commonly seen in activated sludge samples. Strain AG019T was found to be an oxidase-negative, catalase-positive, non-motile aerobe that does not reduce nitrate and grows at temperatures between 15 and 40 °C, with an optimum at 37 °C. The pH range for growth was 5·0–9·0, with an optimum at pH 7·5. Strain AG019T contained a peptidoglycan with directly cross-linked meso-diaminopimelic acid (type A1γ) and lacked mycolic acids. The G+C content of the DNA was 75 mol%. Menaquinone MK-8(H2) was the major isoprenoid quinone. The bacterium stained positively for intracellular polyphosphate granules but not for poly-β-hydroxyalkanoates. It produced capsular material and showed autoaggregation ability. Phenotypic and 16S rRNA gene analyses showed that the bacterium differed sufficiently from its closest phylogenetic relatives, namely members of the suborder Frankineae, which includes the genera Geodermatophilus, Blastococcus, Frankia, Sporichthya, Acidothermus and Microsphaera, that it is proposed that it be placed in a novel genus, Quadrisphaera, as Quadrisphaera granulorum gen. nov., sp. nov. The type strain is AG019T (=ATCC BAA-1104T=DSM 44889T).
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Affiliation(s)
- Abdul Majid Maszenan
- Environmental Engineering Research Centre, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, #N1-01a-09, Singapore 639798
| | - Joo-Hwa Tay
- Environmental Engineering Research Centre, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, #N1-01a-09, Singapore 639798
| | - Peter Schumann
- DSMZ - Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, D-38124 Braunschweig, Germany
| | - He-Long Jiang
- Environmental Engineering Research Centre, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, #N1-01a-09, Singapore 639798
| | - Stephen Tiong-Lee Tay
- Environmental Engineering Research Centre, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, #N1-01a-09, Singapore 639798
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24
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Di Gioia D, Fambrini L, Coppini E, Fava F, Barberio C. Aggregation-based cooperation during bacterial aerobic degradation of polyethoxylated nonylphenols. Res Microbiol 2004; 155:761-9. [PMID: 15501654 DOI: 10.1016/j.resmic.2004.05.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Accepted: 05/25/2004] [Indexed: 10/26/2022]
Abstract
Three bacterial strains were isolated from activated sludge samples of two treatment plants receiving domestic and industrial wastewaters containing polyethoxylated nonylphenols. One strain (VA160) was isolated on rich medium, and the other two (BCaL1 and BCaL2) on mineral medium containing two industrial mixtures of nonylphenol ethoxylates as the sole carbon source. Strain VA160 was a Gram-positive, spore forming, filamentous bacterium, producing aggregates during growth in liquid medium. On the basis of phylogenetic analysis the strains were assigned to the Bacillus (VA160), Acinetobacter (BCaL1) and Stenothrophomonas (BCaL2) genera. High performance liquid chromatography analysis showed that only the Acinetobacter and Stenothrophomonas strains were involved in the degradation of polyethoxylated nonylphenols. Bacillus VA160, however, when co-cultured with the two degrading strains, induced the formation of cell aggregates and facilitated NPEO degradation. Fluorescent in situ hybridisation on the activated sludge sample from which Bacillus VA160 was isolated, using probes for Gram-positive bacteria with low G + C content, showed that bacteria belonging to this group specifically occurred inside the examined flocs. These observations suggest that the enhanced biodegradation of polyethoxylated nonylphenols in the three-membered co-culture is favoured by VA160-induced aggregation of BcaL1 and BcaL2 cells involved in the process.
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MESH Headings
- Acinetobacter/growth & development
- Acinetobacter/metabolism
- Acinetobacter/physiology
- Bacillus/growth & development
- Bacillus/metabolism
- Bacillus/physiology
- Bacteria, Aerobic/classification
- Bacteria, Aerobic/genetics
- Bacteria, Aerobic/metabolism
- Bacterial Adhesion
- Biodegradation, Environmental
- DNA, Ribosomal/analysis
- Ethylene Glycols/metabolism
- In Situ Hybridization, Fluorescence
- Industrial Waste
- Molecular Sequence Data
- Phylogeny
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
- Sewage/microbiology
- Stenotrophomonas/growth & development
- Stenotrophomonas/metabolism
- Stenotrophomonas/physiology
- Waste Disposal, Fluid
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Affiliation(s)
- Diana Di Gioia
- DICASM, Facoltà di Ingegneria, Viale Risorgimento 2, 40136 Bologna, Italy
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25
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Kelley ST, Theisen U, Angenent LT, St Amand A, Pace NR. Molecular analysis of shower curtain biofilm microbes. Appl Environ Microbiol 2004; 70:4187-92. [PMID: 15240300 PMCID: PMC444822 DOI: 10.1128/aem.70.7.4187-4192.2004] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Households provide environments that encourage the formation of microbial communities, often as biofilms. Such biofilms constitute potential reservoirs for pathogens, particularly for immune-compromised individuals. One household environment that potentially accumulates microbial biofilms is that provided by vinyl shower curtains. Over time, vinyl shower curtains accumulate films, commonly referred to as "soap scum," which microscopy reveals are constituted of lush microbial biofilms. To determine the kinds of microbes that constitute shower curtain biofilms and thereby to identify potential opportunistic pathogens, we conducted an analysis of rRNA genes obtained by PCR from four vinyl shower curtains from different households. Each of the shower curtain communities was highly complex. No sequence was identical to one in the databases, and no identical sequences were encountered in the different communities. However, the sequences generally represented similar phylogenetic kinds of organisms. Particularly abundant sequences represented members of the alpha-group of proteobacteria, mainly Sphingomonas spp. and Methylobacterium spp. Both of these genera are known to include opportunistic pathogens, and several of the sequences obtained from the environmental DNA samples were closely related to known pathogens. Such organisms have also been linked to biofilm formation associated with water reservoirs and conduits. In addition, the study detected many other kinds of organisms at lower abundances. These results show that shower curtains are a potential source of opportunistic pathogens associated with biofilms. Frequent cleaning or disposal of shower curtains is indicated, particularly in households with immune-compromised individuals.
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Affiliation(s)
- Scott T Kelley
- Department of Biology, San Diego State University, California 92182, USA
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26
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Beer M, Kong YH, Seviour RJ. Are some putative glycogen accumulating organisms (GAO) in anaerobic : aerobic activated sludge systems members of the α-Proteobacteria? Microbiology (Reading) 2004; 150:2267-2275. [PMID: 15256569 DOI: 10.1099/mic.0.26825-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Activated sludge plants designed to remove phosphorus microbiologically often perform unreliably. One suggestion is that the polyphosphate-accumulating organisms (PAO) are out-competed for substrates by another group of bacteria, the glycogen-accumulating organisms (GAO) in the anaerobic zones of these processes. This study used fluorescence in situ hybridization (FISH) and denaturing gradient gel electrophoresis (DGGE) to analyse the communities from laboratory-scale anaerobic : aerobic sequencing batch reactors. Members of the genus Sphingomonas in the α-Proteobacteria were present in large numbers in communities with poor phosphorus removal capacity where the biomass had a high glycogen content. Their ability to store poly-β-hydroxyalkanoates anaerobically, but not aerobically, and not accumulate polyphosphate aerobically is consistent with these organisms behaving as GAO there. No evidence was found to support an important role for the γ-Proteobacteria as possible GAO in these communities, although these bacterial populations have been considered in other studies to act as possible competitors for the PAO.
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Affiliation(s)
- Michael Beer
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
| | - Yun H Kong
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
| | - Robert J Seviour
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria 3552, Australia
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27
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Aulenta F, Dionisi D, Majone M, Parisi A, Ramadori R, Tandoi V. Effect of periodic feeding in sequencing batch reactor on substrate uptake and storage rates by a pure culture of Amaricoccus kaplicensis. WATER RESEARCH 2003; 37:2764-2772. [PMID: 12753855 DOI: 10.1016/s0043-1354(03)00059-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A pure culture of Amaricoccus kaplicensis was aerobically cultured at a long culture residence time (Theta(C)>12d), under periodic acetate feeding in a sequencing batch reactor (SBR). The cycle length and, correspondingly, the volumetric organic load rate (vOLR) were varied in the range 4-24h and 0.76-0.12gCODl(-1)d(-1), respectively. The transient response of the microorganism to the acetate spike was investigated throughout batch tests, as a function of SBR cycle length and vOLR. In all tested conditions, a rapid transient response was observed, mainly due to acetate storage in the form of polyhydroxybutyrate, since growth (production of active biomass) played a minor role. Apart from this general trend, the maximum rates under transient conditions increased as the cycle length increased from 4 to 24h. In the SBR, the longest cycle also caused a decrease in floc size and settleability as well as an increase in the observed yield. The observed effect of SBR operating conditions on the physiological state of cells and their related transient response may have great significance on the performance of full scale activated sludge processes.
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Affiliation(s)
- Federico Aulenta
- Department of Chemistry, University of Rome La Sapienza, P. le Aldo Moro 5, 00185 Rome, Italy
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28
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Lee N, Nielsen PH, Aspegren H, Henze M, Schleifer KH, la Cour Jansen J. Long-term population dynamics and in situ physiology in activated sludge systems with enhanced biological phosphorus removal operated with and without nitrogen removal. Syst Appl Microbiol 2003; 26:211-27. [PMID: 12866848 DOI: 10.1078/072320203322346065] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Quantitative fluorescence in situ hybridization (FISH) and the combination of FISH with microautoradiography (MAR) were used in order to study the long-term population dynamics (2.5 years) and the in situ physiology in two parallel activated sludge pilot systems with enhanced biological phosphorus removal (EBPR). The two systems received the same influent wastewater, but were differently operated (with and without nitrogen removal, respectively). Both systems showed a significant P removal that increased when different substrates (phosphorus (P), acetate and glucose, respectively) were added to the influent wastewater. Rhodocyclus-related bacteria were present in both systems in significant numbers (ranging from 4 to 28%) throughout the whole period. This supports the hypothesis that these bacteria occur in significant numbers in different types of well-operating EBPR activated sludge processes. However, we observed a lower correlation (< 0.5) for the amount of Rhodocyclus-related bacteria to the P content in activated sludge than previous studies (> 0.9). The Actinobacteria were the only additional group of bacteria which showed a similar degree of correlation to the P content in activated sludge as the Rhodocyclus-related bacteria--but only for the system without nitrogen removal. Significant amounts (< or = 12%) of glycogen-accumulating bacteria (GAOs) were detected in the system with nitrogen removal (but not in the other system), but had no, in contrast to previous observations, apparent negative effect on the overall EBPR performance. FISH-MAR indicated that a significant part of the Betaproteobacteria (part of them identified as Rhodocyclus-related bacteria) as well as the Actinobacteria were able to take up 33Pi, [3H]-acetate and [3H]-glucose under anaerobic-aerobic conditions. The contribution of anoxic 33Pi uptake under alternating anaerobic-anoxic conditions was significantly lower. Interestingly, not all Rhodocyclus-related bacteria showed uptake of these three radioactive substrates. This may be due to differences in metabolic state, physiological potential or genotype, not detectable by the present probe set for Rhodocyclus-related bacteria. Comparison of the 33Pi, [3H]-acetate and [3H]-glucose uptake by activated sludge after different fixation and incubation procedures showed that a part of the observed 33Pi uptake may have been caused by a combination of a biological and chemical or biologically induced chemical P adsorption.
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Affiliation(s)
- Natuschka Lee
- Lehrstuhl für Mikrobiologie, TU München, Freising, Germany.
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Seviour RJ, Mino T, Onuki M. The microbiology of biological phosphorus removal in activated sludge systems. FEMS Microbiol Rev 2003; 27:99-127. [PMID: 12697344 DOI: 10.1016/s0168-6445(03)00021-4] [Citation(s) in RCA: 448] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Activated sludge systems are designed and operated globally to remove phosphorus microbiologically, a process called enhanced biological phosphorus removal (EBPR). Yet little is still known about the ecology of EBPR processes, the microbes involved, their functions there and the possible reasons why they often perform unreliably. The application of rRNA-based methods to analyze EBPR community structure has changed dramatically our understanding of the microbial populations responsible for EBPR, but many substantial gaps in our knowledge of the population dynamics of EBPR and its underlying mechanisms remain. This review critically examines what we once thought we knew about the microbial ecology of EBPR, what we think we now know, and what still needs to be elucidated before these processes can be operated and controlled more reliably than is currently possible. It looks at the history of EBPR, the currently available biochemical models, the structure of the microbial communities found in EBPR systems, possible identities of the bacteria responsible, and the evidence why these systems might operate suboptimally. The review stresses the need to extend what have been predominantly laboratory-based studies to full-scale operating plants. It aims to encourage microbiologists and process engineers to collaborate more closely and to bring an interdisciplinary approach to bear on this complex ecosystem.
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Affiliation(s)
- Robert J Seviour
- Institute of Environmental Studies, Graduate School of Frontier Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan.
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Serafim LS, Lemos PC, Levantesi C, Tandoi V, Santos H, Reis MAM. Methods for detection and visualization of intracellular polymers stored by polyphosphate-accumulating microorganisms. J Microbiol Methods 2002; 51:1-18. [PMID: 12069885 DOI: 10.1016/s0167-7012(02)00056-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Polyphosphate-accumulating microorganisms (PAOs) are important in enhanced biological phosphorus (P) removal. Considerable effort has been devoted to understanding the biochemical nature of enhanced biological phosphorus removal (EBPR) and it has been shown that intracellular polymer storage plays an important role in PAO's metabolism. The storage capacity of PAOs gives them a competitive advantage over other microorganisms present that are not able to accumulate internal reserves. Intracellular polymers stored by PAOs include polyphosphate (poly-P), polyhydroxyalkanoates (PHAs) and glycogen. Staining procedures for qualitative visualization of polymers by optical microscopy and combinations of these procedures with molecular tools for in situ identification are described here. The strengths and weaknesses of widely used polymer quantification methods that require destruction of samples, are also discussed. Finally, the potential of in vivo nuclear magnetic resonance (NMR) spectroscopy for on-line measurement of intracellular reserves is reported.
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Affiliation(s)
- Luísa S Serafim
- Departamento de Química, CQFB/REQUIMTE, FCT/Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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Kong YH, Beer M, Rees GN, Seviour RJ. Functional analysis of microbial communities in aerobic-anaerobic sequencing batch reactors fed with different phosphorus/carbon (P/C) ratios. MICROBIOLOGY (READING, ENGLAND) 2002; 148:2299-2307. [PMID: 12177324 DOI: 10.1099/00221287-148-8-2299] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Fluorescence in situ hybridization (FISH) was used to analyse the community composition of a sequencing batch reactor (SBR) operating with aerobic-anaerobic cycling and fed acetate as its sole carbon source. Phosphorus was removed from the SBR microbiologically. Marked shifts in the community structure occurred as the phosphorus/carbon (P/C) ratio in the feed was changed. When the P/C ratio was shifted from 1:10 to 1:50, FISH analysis showed that the percentage of beta-Proteobacteria fell from ca 77% of the total bacteria to ca 38%. This decrease in the beta-Proteobacteria coincided with a reduction in both the proportions of the beta-proteobacterial Rhodocyclus-related phosphorus-accumulating bacteria and the biomass phosphorus content. FISH/microautoradiography and FISH/poly beta-hydroxyalkanoate (PHA) staining showed that the Rhodocyclus-related bacteria assimilated acetate and synthesized PHAs anaerobically, and that they accumulated phosphorus aerobically. No Acinetobacter spp. could be detected in any of the communities, casting further doubt on their role in phosphorus-removing activated sludge systems. As the feed P/C ratio decreased there was a corresponding increase in the proportion of alpha-Proteobacteria and, to a smaller extent, in the proportion of gamma-Proteobacteria; both the alpha- and gamma-Proteobacteria consisted mostly of tetrad-forming cocci, fitting the description of the so-called 'G-bacteria' morphotype. The change in the proportions of Proteobacteria present paralleled increases in the biomass glycogen content. Both the alpha- and beta-proteobacterial 'G-bacterial' populations assimilated acetate and synthesized PHA anaerobically. The alpha-Proteobacteria are considered responsible for glycogen production in these SBR systems.
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Affiliation(s)
- Yun H Kong
- Biotechnology Research Centre, La Trobe University, Bendigo, 3552 Victoria, Australia1
| | - Michael Beer
- Biotechnology Research Centre, La Trobe University, Bendigo, 3552 Victoria, Australia1
| | - Gavin N Rees
- Murray-Darling Freshwater Research Centre and CRC for Freshwater Ecology, Albury, 2640 NSW, Australia2
| | - Robert J Seviour
- Biotechnology Research Centre, La Trobe University, Bendigo, 3552 Victoria, Australia1
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Abstract
The application of modern molecular techniques has led to the identification, in situ quantification, and partial ecophysiological characterisation of bacteria responsible for bulking and foaming or for nutrient removal in sewage treatment systems. Unexpectedly, previously unrecognised, yet uncultured bacteria were demonstrated to catalyse nitrogen and phosphorous removal in activated-sludge and biofilm reactors. These findings provide the basis for the development of novel concepts for improving the efficiency and functional stability of waste water treatment systems.
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Affiliation(s)
- Michael Wagner
- Microbial Ecology Group, Lehrstuhl für Mikrobiologie, Technische Universität München, Am Hochanger 4, D-85350 Freising, Germany.
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Kong YH, Beer M, Seviour RJ, Lindrea KC, Rees GN. Structure and functional analysis of the microbial community in an aerobic: anaerobic sequencing batch reactor (SBR) with no phosphorus removal. Syst Appl Microbiol 2001; 24:597-609. [PMID: 11876367 DOI: 10.1078/0723-2020-00075] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The bacterial community of an aerobic:anaerobic non-P removing SBR biomass fed a mixture of acetate and glucose was analysed using several 16S rRNA based methods. Populations responsible for anaerobic glucose and acetate assimilation were determined with fluorescent in situ hybridization (FISH) in combination with microautoradiography (FISH/MAR). At 'steady state' this community consisted of alpha-Proteobacteria (26%) and gamma-Proteobacteria (14%), mainly appearing as large cocci in tetrads (i.e. typical 'G-Bacteria'). Large numbers of low G+C bacteria (22%), and high G+C Gram-positive bacteria (29%) seen as small cocci in clusters or in sheets were also detected after FISH. DGGE fingerprinting of PCR amplified 16S rDNA fragments and subsequent cloning and sequencing of several of the major bands led to the identification of some of these populations. They included an organism 98% similar in its 16S rRNA sequence to Micropruina glycogenica, and ca. 76% of the high G+C bacteria responded to a probe MIC 184, designed against it. The rest responded to the KSB 531 probe designed against a high G+C clone sequence, sbr-gs28 reported in other similar systems. FISH analyses showed that both these high G+C populations were almost totally dominated by small clustered cocci. Only ca. 2% of cells were beta-Proteobacteria. None of the alpha- and gamma-Proteobacterial 'G-bacteria' responded to FISH probes designed for the 'G-Bacteria' Amaricoccus spp. or Defluvicoccus vanus. FISH/MAR revealed that not all the alpha-Proteobacterial 'G-Bacteria' could take up acetate or glucose anaerobically. Almost all of the gamma-Proteobacterial 'G-Bacteria' assimilated acetate anaerobically but not glucose, the low G+C clustered cocci only took up glucose, whereas the high G+C bacteria including M. glycogenica and the sbr-gs28 clone assimilated both acetate and glucose. All bacteria other than the low G+C small cocci and a few of the alpha-Proteobacteria accumulated PHB. The low G+C bacteria showing anaerobic glucose assimilation ability were considered responsible for the lactic acid produced anaerobically by this SBR biomass, and M. glycogenica for its high glycogen content.
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MESH Headings
- Acetates/metabolism
- Autoradiography
- Bacteria, Aerobic/genetics
- Bacteria, Aerobic/metabolism
- Bacteria, Anaerobic/genetics
- Bacteria, Anaerobic/metabolism
- Bioreactors/microbiology
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Glucose/metabolism
- Image Processing, Computer-Assisted
- In Situ Hybridization, Fluorescence
- Phosphates/metabolism
- Phylogeny
- RNA, Ribosomal, 16S/chemistry
- RNA, Ribosomal, 16S/genetics
- Water Microbiology
- Water Purification/methods
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Affiliation(s)
- Y H Kong
- Biotechnology Research Centre, La Trobe University, Bendigo, Victoria, Australia
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