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Zhang Y, Xiang Y, Yang Z, Xu R. Co-occurrence of dominant bacteria and methanogenic archaea and their metabolic traits in a thermophilic anaerobic digester. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:36716-36727. [PMID: 38753237 DOI: 10.1007/s11356-024-33699-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 05/13/2024] [Indexed: 06/20/2024]
Abstract
Thermophilic anaerobic digestion (TAD) represents a promising biotechnology for both methane energy production and waste stream treatment. However, numerous critical microorganisms and their metabolic characteristics involved in this process remain unidentified due to the limitations of culturable isolates. This study investigated the phylogenetic composition and potential metabolic traits of bacteria and methanogenic archaea in a TAD system using culture-independent metagenomics. Predominant microorganisms identified in the stable phase of TAD included hydrogenotrophic methanogens (Methanothermobacter and Methanosarcina) and hydrogen-producing bacteria (Coprothermobacter, Acetomicrobium, and Defluviitoga). Nine major metagenome-assembled genomes (MAGs) associated with the dominant genera were selected to infer their metabolic potentials. Genes related to thermal resistance were widely found in all nine major MAGs, such as the molecular chaperone genes, Clp protease gene, and RNA polymerase genes, which may contribute to their predominance under thermophilic condition. Thermophilic temperatures may increase the hydrogen partial pressure of Coprothermobacter, Acetomicrobium, and Defluviitoga, subsequently altering the primary methanogenesis pathway from acetoclastic pathway to hydrogenotrophic pathway in the TAD. Consequently, genes encoding the hydrogenotrophic methanogenesis pathway were the most abundant in the recovered archaeal MAGs. The potential interaction between hydrogen-producing bacteria and hydrogenotrophic methanogens may play critical roles in TAD processes.
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Affiliation(s)
- Yanru Zhang
- Fujian Key Laboratory of Pollution Control & Resource Reuse, College of Environmental and Resource Sciences, Fujian Normal University, Fuzhou, 350007, People's Republic of China
| | - Yinping Xiang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China
| | - Zhaohui Yang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China
| | - Rui Xu
- School of Metallurgy and Environment, Central South University, No. 932 Lushan South Road, Changsha, 410083, China.
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Aho VTE, Tolonen T, Haverinen J, Jaakkola M, Paulin L, Auvinen P, Laine MM. Survey of microbes in industrial-scale second-generation bioethanol production for better process knowledge and operation. Appl Microbiol Biotechnol 2020; 104:8049-8064. [PMID: 32785760 DOI: 10.1007/s00253-020-10818-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 06/30/2020] [Accepted: 08/05/2020] [Indexed: 11/24/2022]
Abstract
The microbes present in bioethanol production processes have been previously studied in laboratory-scale experiments, but there is a lack of information on full-scale industrial processes. In this study, the microbial communities of three industrial bioethanol production processes were characterized using several methods. The samples originated from second-generation bioethanol plants that produce fuel ethanol from biowaste, food industry side streams, or sawdust. Amplicon sequencing targeting bacteria, archaea, and fungi was used to explore the microbes present in biofuel production and anaerobic digestion of wastewater and sludge. Biofilm-forming lactic acid bacteria and wild yeasts were identified in fermentation samples of a full-scale plant that uses biowaste as feedstock. During the 20-month monitoring period, the anaerobic digester adapted to the bioethanol process waste with a shift in methanogen profile indicating acclimatization to high concentrations of ammonia. Amplicon sequencing does not specifically target living microbes. The same is true for indirect parameters, such as low pH, metabolites, or genes of lactic acid bacteria. Since rapid identification of living microbes would be indispensable for process management, a commercial method was tested that detects them by measuring the rRNA of selected microbial groups. Small-scale testing indicated that the method gives results comparable with plate counts and microscopic counting, especially for bacterial quantification. The applicability of the method was verified in an industrial bioethanol plant, inspecting the clean-in-place process quality and detecting viability during yeast separation. The results supported it as a fast and promising tool for monitoring microbes throughout industrial bioethanol processes.
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Affiliation(s)
- Velma T E Aho
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland.,Department of Neurology, Helsinki University Hospital, Helsinki, Finland
| | - Tiina Tolonen
- Unit of Measurement Technology, Kajaani University Consortium, University of Oulu, Kajaani, Finland
| | - Jasmiina Haverinen
- Unit of Measurement Technology, Kajaani University Consortium, University of Oulu, Kajaani, Finland
| | - Mari Jaakkola
- Unit of Measurement Technology, Kajaani University Consortium, University of Oulu, Kajaani, Finland
| | - Lars Paulin
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Petri Auvinen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
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Fernandez‐Gonzalez N, Pedizzi C, Lema JM, Carballa M. Air-side ammonia stripping coupled to anaerobic digestion indirectly impacts anaerobic microbiome. Microb Biotechnol 2019; 12:1403-1416. [PMID: 31532080 PMCID: PMC6801131 DOI: 10.1111/1751-7915.13482] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 06/26/2019] [Accepted: 08/13/2019] [Indexed: 11/29/2022] Open
Abstract
Air-side stripping without a prior solid-liquid phase separation step is a feasible and promising process to control ammonia concentration in thermophilic digesters. During the process, part of the anaerobic biomass is exposed to high temperature, high pH and aerobic conditions. However, there are no studies assessing the effects of those harsh conditions on the microbial communities of thermophilic digesters. To fill this knowledge gap, the microbiomes of two thermophilic digesters (55°C), fed with a mixture of pig manure and nitrogen-rich co-substrates, were investigated under different organic loading rates (OLR: 1.1-5.2 g COD l-1 day-1 ), ammonia concentrations (0.2-1.5 g free ammonia nitrogen l-1 ) and stripping frequencies (3-5 times per week). The bacterial communities were dominated by Firmicutes and Bacteroidetes phyla, while the predominant methanogens were Methanosarcina sp archaea. Increasing co-substrate fraction, OLR and free ammonia nitrogen (FAN) favoured the presence of genera Ruminiclostridium, Clostridium and Tepidimicrobium and of hydrogenotrophic methanogens, mainly Methanoculleus archaea. The data indicated that the use of air-side stripping did not adversely affect thermophilic microbial communities, but indirectly modulated them by controlling FAN concentrations in the digester. These results demonstrate the viability at microbial community level of air side-stream stripping process as an adequate technology for the ammonia control during anaerobic co-digestion of nitrogen-rich substrates.
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Affiliation(s)
- Nuria Fernandez‐Gonzalez
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
- Present address:
Present address:Department of Chemical Engineering and Environmental TechnologyValladolid UniversityDr. Mergelina, s/n47011ValladolidSpain
| | - Chiara Pedizzi
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
| | - Juan M. Lema
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
| | - Marta Carballa
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
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Langer SG, Gabris C, Einfalt D, Wemheuer B, Kazda M, Bengelsdorf FR. Different response of bacteria, archaea and fungi to process parameters in nine full-scale anaerobic digesters. Microb Biotechnol 2019; 12:1210-1225. [PMID: 30995692 PMCID: PMC6801161 DOI: 10.1111/1751-7915.13409] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/09/2019] [Accepted: 03/29/2019] [Indexed: 01/20/2023] Open
Abstract
Biogas production is a biotechnological process realized by complex bacterial, archaeal and likely fungal communities. Their composition was assessed in nine full-scale biogas plants with distinctly differing feedstock input and process parameters. This study investigated the actually active microbial community members by using a comprehensive sequencing approach based on ribosomal 16S and 28S rRNA fragments. The prevailing taxonomical units of each respective community were subsequently linked to process parameters. Ribosomal rRNA of bacteria, archaea and fungi, respectively, showed different compositions with respect to process parameters and supplied feedstocks: (i) bacterial communities were affected by the key factors temperature and ammonium concentration; (ii) composition of archaea was mainly related to process temperature; and (iii) relative abundance of fungi was linked to feedstocks supplied to the digesters. Anaerobic digesters with a high methane yield showed remarkably similar bacterial communities regarding identified taxonomic families. Although archaeal communities differed strongly on genus level from each other, the respective digesters still showed high methane yields. Functional redundancy of the archaeal communities may explain this effect. 28S rRNA sequences of fungi in all nine full-scale anaerobic digesters were primarily classified as facultative anaerobic Ascomycota and Basidiomycota. Since the presence of ribosomal 28S rRNA indicates that fungi may be active in the biogas digesters, further research should be carried out to examine to which extent they are important players in anaerobic digestion processes.
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MESH Headings
- Anaerobiosis
- Archaea/classification
- Archaea/genetics
- Archaea/growth & development
- Bacteria, Anaerobic/classification
- Bacteria, Anaerobic/genetics
- Bacteria, Anaerobic/growth & development
- Biofuels
- Bioreactors/microbiology
- Cluster Analysis
- DNA, Archaeal/chemistry
- DNA, Archaeal/genetics
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Fungal/chemistry
- DNA, Fungal/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Fungi/classification
- Fungi/genetics
- Fungi/growth & development
- Manure/microbiology
- Metagenomics
- Microbiota
- Phylogeny
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 28S/genetics
- Sequence Analysis, DNA
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Affiliation(s)
| | - Christina Gabris
- Institute of Microbiology and BiotechnologyUlm UniversityUlmGermany
- Present address:
Bühlmann Laboratories AGSchönenbuchSwitzerland
| | - Daniel Einfalt
- Institute of Systematic Botany and EcologyUlm UniversityUlmGermany
- Present address:
Institute of Food Science and BiotechnologyUniversity of HohenheimStuttgartGermany
| | - Bernd Wemheuer
- Genomic and Applied Microbiology & Göttingen Genomics LaboratoryGeorg‐August University GöttingenGöttingenGermany
| | - Marian Kazda
- Institute of Systematic Botany and EcologyUlm UniversityUlmGermany
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Microbial Profile of the Leachate from Mexico City’s Bordo Poniente Composting Plant: An Inoculum to Digest Organic Waste. ENERGIES 2019. [DOI: 10.3390/en12122343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In recent years, municipal solid waste (MSW) management has become a complex problem worldwide. Similarly, Mexico City is facing such a situation for the management and treatment of organic fraction of municipal solid waste (OFMSW). Therefore, in this work, we investigated whether leachate from the composting plant, Bordo Poniente, located in Mexico City can be used as an inoculum for the treatment of OFMSW using thermophilic anaerobic digestion (AD) with a hydraulic retention time of 30 days. We analyzed the physicochemical properties of the leachate and performed a biochemical methane potential test. Archaeal and bacterial diversity was also identified using high throughput DNA sequencing of 16S rDNA libraries. Methane yield was 0.29 m3 CH4/kg VSadded in the positive control and 0.16 m3 CH4/kg VSadded in the treatment group. The phylum, Bacteroidetes, and genus, Methanosarcina, prevailed in the leachate. However, in thermophilic conditions, the microbial communities changed, and the phylum, Firmicutes, genera, Methanoculleus, and candidate genus, vadinCA11, were dominant in the treatment group. We concluded that the leachate contains a suitable initial charge of many active bacteria and methanogenic archaea which contribute to the AD process, hence it can be used as an inoculum for the treatment of OFMSW.
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Planý M, Czolderová M, Kraková L, Puškárová A, Bučková M, Šoltys K, Budiš J, Szemes T, Mackulak T, Wu JH, Pangallo D. Biogas production: evaluation of the influence of K2FeO4 pretreatment of maple leaves (Acer platanoides) on microbial consortia composition. Bioprocess Biosyst Eng 2019; 42:1151-1163. [DOI: 10.1007/s00449-019-02112-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 03/20/2019] [Indexed: 10/27/2022]
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Greses S, Zamorano-López N, Borrás L, Ferrer J, Seco A, Aguado D. Effect of long residence time and high temperature over anaerobic biodegradation of Scenedesmus microalgae grown in wastewater. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 218:425-434. [PMID: 29709811 DOI: 10.1016/j.jenvman.2018.04.086] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 04/11/2018] [Accepted: 04/20/2018] [Indexed: 06/08/2023]
Abstract
Anaerobic digestion of indigenous Scenedesmus spp. microalgae was studied in continuous lab-scale anaerobic reactors at different temperatures (35 °C and 55 °C), and sludge retention time - SRT (50 and 70 days). Mesophilic digestion was performed in a continuous stirred-tank reactor (CSTR) and in an anaerobic membrane bioreactor (AnMBR). Mesophilic CSTR operated at 50 days SRT only achieved 11.9% of anaerobic biodegradability whereas in the AnMBR at 70 days SRT and 50 days HRT reached 39.5%, which is even higher than the biodegradability achieved in the thermophilic CSTR at 50 days SRT (30.4%). Microbial analysis revealed a high abundance of cellulose-degraders in both reactors, AnMBR (mainly composed of 9.4% Bacteroidetes, 10.1% Chloroflexi, 8.0% Firmicutes and 13.2% Thermotogae) and thermophilic CSTR (dominated by 23.8% Chloroflexi and 12.9% Firmicutes). However, higher microbial diversity was found in the AnMBR compared to the thermophilic CSTR which is related to the SRT. since high SRT promoted low growth-rate microorganisms, increasing the hydrolytic potential of the system. These results present the membrane technology as a promising approach to revalue microalgal biomass, suggesting that microalgae biodegradability and consequently the methane production could be improved operating at higher SRT.
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Affiliation(s)
- S Greses
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Av. de la Universitat s/n, 46100, Burjassot, Valencia, Spain.
| | - N Zamorano-López
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Av. de la Universitat s/n, 46100, Burjassot, Valencia, Spain.
| | - L Borrás
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Av. de la Universitat s/n, 46100, Burjassot, Valencia, Spain.
| | - J Ferrer
- CALAGUA - Unidad Mixta UV-UPV, Institut Universitari d'Investigació d'Enginyeria de l'Aigua i Medi Ambient - IIAMA, Universitat Politècnica de Valencia, Camí de Vera s/n, 46022, Valencia, Spain.
| | - A Seco
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Av. de la Universitat s/n, 46100, Burjassot, Valencia, Spain.
| | - D Aguado
- CALAGUA - Unidad Mixta UV-UPV, Institut Universitari d'Investigació d'Enginyeria de l'Aigua i Medi Ambient - IIAMA, Universitat Politècnica de Valencia, Camí de Vera s/n, 46022, Valencia, Spain.
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Wang P, Yu Z, Zhao J, Zhang H. Do microbial communities in an anaerobic bioreactor change with continuous feeding sludge into a full-scale anaerobic digestion system? BIORESOURCE TECHNOLOGY 2018; 249:89-98. [PMID: 29040865 DOI: 10.1016/j.biortech.2017.09.191] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/26/2017] [Accepted: 09/28/2017] [Indexed: 06/07/2023]
Abstract
Microbial communities of sludge samples from a full-scale anaerobic digestion (AD) fed with primary sludge (PS) and excess sludge (ES) were analyzed using qPCR and MiSeq. The results showed that the microbial composition of digested sludge remained relatively stable but was partially changed by microbial immigration from feeding sludge. The dominant archaea in the digested sludge were largely the same as those in the feeding sludge, but their abundances differed markedly. The dominant fungal genera in the digested sludge were different from those in PS but were similar to those in ES. Various differences in bacterial community differences between digested sludge and PS/ES were observed. Notably, this study is the first to suggest Verrucomicrobia is the predominant bacterial phylum in the digested sludge, and that numerous unreported microorganisms belonging to the order LD1-PB3 existed in this AD system and potentially played roles in the processes of hydrolysis, fermentation, and acetogenesis.
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Affiliation(s)
- Ping Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, PR China
| | - Zhisheng Yu
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, PR China.
| | - Jihong Zhao
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, No. 166, Science Avenue, Zhengzhou 450001, PR China
| | - Hongxun Zhang
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, PR China
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Abendroth C, Simeonov C, Peretó J, Antúnez O, Gavidia R, Luschnig O, Porcar M. From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:171. [PMID: 28690680 PMCID: PMC5496412 DOI: 10.1186/s13068-017-0859-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 06/27/2017] [Indexed: 05/24/2023]
Abstract
BACKGROUND Separating acidification and methanogenic steps in anaerobic digestion processes can help to optimize the process and contribute to producing valuable sub-products such as methane, hydrogen and organic acids. However, the full potential of this technology has not been fully explored yet. To assess the underlying fermentation process in more detail, a combination of high-throughput sequencing and proteomics on the acidification step of plant material (grass) at both mesophilic and thermophilic temperatures (37 and 55 °C, respectively) was applied for the first time. RESULTS High-strength liquor from acidified grass biomass exhibited a low biodiversity, which differed greatly depending on temperature. It was dominated by Bacteroidetes and Firmicutes at 37 °C, and by Firmicutes and Proteobacteria at 55 °C. At the methane stage, Methanosaeta, Methanomicrobium and Methanosarcina proved to be highly sensitive to environmental changes as their abundance in the seed sludges dropped dramatically after transferring the seed sludges from the respective reactors into the experimental setup. Further, an increase in Actinobacteria coincided with reduced biogas production at the end of the experiment. Over 1700 proteins were quantified from the first cycle of acidification samples using label-free quantitative proteome analysis and searching protein databases. The most abundant proteins included an almost complete set of glycolytic enzymes indicating that the microbial population is basically engaged in the degradation and catabolism of sugars. Differences in protein abundances clearly separated samples into two clusters corresponding to culture temperature. More differentially expressed proteins were found under mesophilic (120) than thermophilic (5) conditions. CONCLUSION Our results are the first multi-omics characterisation of a two-stage biogas production system with separated acidification and suggest that screening approaches targeting specific taxa such as Methanosaeta, Methanomicrobium and Methanosarcina could be useful diagnostic tools as indicators of environmental changes such as temperature or oxidative stress or, as in the case of Actinobacteria, they could be used as a proxy of the gas production potential of anaerobic digesters. Metaproteome analyses only detected significant expression differences in mesophilic samples, whereas thermophilic samples showed more stable protein composition with an abundance of chaperones suggesting a role in protein stability under thermal stress.
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Affiliation(s)
- Christian Abendroth
- Cavanilles Institute of Biodiversity and Evolutionary Biology, Universitat de València, C/ José Beltran 2, 46980 Paterna, Spain
- Institute for Integrative Systems Biology (I2SysBio, Universitat de València-CSIC), C/ José Beltran 2, 46980 Paterna, Spain
- Robert Boyle Institut e.V., Im Steinfeld 10, 07751 Jena, Germany
| | - Claudia Simeonov
- Robert Boyle Institut e.V., Im Steinfeld 10, 07751 Jena, Germany
| | - Juli Peretó
- Cavanilles Institute of Biodiversity and Evolutionary Biology, Universitat de València, C/ José Beltran 2, 46980 Paterna, Spain
- Institute for Integrative Systems Biology (I2SysBio, Universitat de València-CSIC), C/ José Beltran 2, 46980 Paterna, Spain
- Departament de Bioquímica i Biologia Molecular, Universitat de València, Paterna, Spain
- Darwin Bioprospecting Excellence, S.L. Parc Cientific Universitat de Valencia, C/ Catedrático Agustín Escardino Benlloch, 9, 46980 Paterna, Valencia Spain
| | - Oreto Antúnez
- Servei Central de Suport a la Investigació Experimental (SCSIE), Universitat de València-CSIC, Paterna, Spain
| | - Raquel Gavidia
- Servei Central de Suport a la Investigació Experimental (SCSIE), Universitat de València-CSIC, Paterna, Spain
| | - Olaf Luschnig
- Bio H2 Energy GmbH, Im Steinfeld 10, 07751 Jena, Germany
| | - Manuel Porcar
- Cavanilles Institute of Biodiversity and Evolutionary Biology, Universitat de València, C/ José Beltran 2, 46980 Paterna, Spain
- Institute for Integrative Systems Biology (I2SysBio, Universitat de València-CSIC), C/ José Beltran 2, 46980 Paterna, Spain
- Darwin Bioprospecting Excellence, S.L. Parc Cientific Universitat de Valencia, C/ Catedrático Agustín Escardino Benlloch, 9, 46980 Paterna, Valencia Spain
- Institute for Integrative Systems Biology (I2SysBio, Universitat de València-CSIC), Postal Code 22085, 46071 Paterna, València Spain
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Mykrä H, Tolkkinen M, Heino J. Environmental degradation results in contrasting changes in the assembly processes of stream bacterial and fungal communities. OIKOS 2017. [DOI: 10.1111/oik.04133] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Heikki Mykrä
- Finnish Environment Inst., Freshwater Centre; PO Box 413 FI-90014, Oulu Finland
| | | | - Jani Heino
- Finnish Environment Inst., Natural Environment Centre, Biodiversity; Oulu Finland
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Maus I, Cibis KG, Bremges A, Stolze Y, Wibberg D, Tomazetto G, Blom J, Sczyrba A, König H, Pühler A, Schlüter A. Genomic characterization of Defluviitoga tunisiensis L3, a key hydrolytic bacterium in a thermophilic biogas plant and its abundance as determined by metagenome fragment recruitment. J Biotechnol 2016; 232:50-60. [PMID: 27165504 DOI: 10.1016/j.jbiotec.2016.05.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 05/02/2016] [Accepted: 05/02/2016] [Indexed: 12/17/2022]
Abstract
The genome sequence of Defluviitoga tunisiensis L3 originating from a thermophilic biogas-production plant was established and recently published as Genome Announcement by our group. The circular chromosome of D. tunisiensis L3 has a size of 2,053,097bp and a mean GC content of 31.38%. To analyze the D. tunisiensis L3 genome sequence in more detail, a phylogenetic analysis of completely sequenced Thermotogae strains based on shared core genes was performed. It appeared that Petrotoga mobilis DSM 10674(T), originally isolated from a North Sea oil-production well, is the closest relative of D. tunisiensis L3. Comparative genome analyses of P. mobilis DSM 10674(T) and D. tunisiensis L3 showed moderate similarities regarding occurrence of orthologous genes. Both genomes share a common set of 1351 core genes. Reconstruction of metabolic pathways important for the biogas production process revealed that the D. tunisiensis L3 genome encodes a large set of genes predicted to facilitate utilization of a variety of complex polysaccharides including cellulose, chitin and xylan. Ethanol, acetate, hydrogen (H2) and carbon dioxide (CO2) were found as possible end-products of the fermentation process. The latter three metabolites are considered to represent substrates for methanogenic Archaea, the key organisms in the final step of the anaerobic digestion process. To determine the degree of relatedness between D. tunisiensis L3 and dominant biogas community members within the thermophilic biogas-production plant, metagenome sequences obtained from the corresponding microbial community were mapped onto the L3 genome sequence. This fragment recruitment revealed that the D. tunisiensis L3 genome is almost completely covered with metagenome sequences featuring high matching accuracy. This result indicates that strains highly related or even identical to the reference strain D. tunisiensis L3 play a dominant role within the community of the thermophilic biogas-production plant.
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Affiliation(s)
- Irena Maus
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | - Katharina Gabriela Cibis
- Institute of Microbiology and Wine Research, Johannes Gutenberg University Mainz, 55122 Mainz, Germany
| | - Andreas Bremges
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany; Faculty of Technology, Bielefeld University, 33615 Bielefeld, Germany
| | - Yvonne Stolze
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | - Daniel Wibberg
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | | | - Jochen Blom
- Department of Bioinformatics and Systems Biology, Justus-Liebig-University Gießen, 35390 Gießen, Germany
| | - Alexander Sczyrba
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany; Faculty of Technology, Bielefeld University, 33615 Bielefeld, Germany
| | - Helmut König
- Institute of Microbiology and Wine Research, Johannes Gutenberg University Mainz, 55122 Mainz, Germany
| | - Alfred Pühler
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | - Andreas Schlüter
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany.
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Kalia VC, Prakash J, Koul S. Biorefinery for Glycerol Rich Biodiesel Industry Waste. Indian J Microbiol 2016; 56:113-25. [PMID: 27570302 DOI: 10.1007/s12088-016-0583-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 04/12/2016] [Indexed: 11/30/2022] Open
Abstract
The biodiesel industry has the potential to meet the fuel requirements in the future. A few inherent lacunae of this bioprocess are the effluent, which is 10 % of the actual product, and the fact that it is 85 % glycerol along with a few impurities. Biological treatments of wastes have been known as a dependable and economical direction of overseeing them and bring some value added products as well. A novel eco-biotechnological strategy employs metabolically diverse bacteria, which ensures higher reproducibility and economics. In this article, we have opined, which organisms and what bioproducts should be the focus, while exploiting glycerol as feed.
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Affiliation(s)
- Vipin Chandra Kalia
- Microbial Biotechnology and Genomics, CSIR - Institute of Genomics and Integrative Biology (IGIB), Delhi University Campus, Mall Road, Delhi, 110007 India ; Academy for Scientific and Innovative Research (AcSIR), 2 Rafi Marg, New Delhi, 110001 India
| | - Jyotsana Prakash
- Microbial Biotechnology and Genomics, CSIR - Institute of Genomics and Integrative Biology (IGIB), Delhi University Campus, Mall Road, Delhi, 110007 India ; Academy for Scientific and Innovative Research (AcSIR), 2 Rafi Marg, New Delhi, 110001 India
| | - Shikha Koul
- Microbial Biotechnology and Genomics, CSIR - Institute of Genomics and Integrative Biology (IGIB), Delhi University Campus, Mall Road, Delhi, 110007 India ; Academy for Scientific and Innovative Research (AcSIR), 2 Rafi Marg, New Delhi, 110001 India
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13
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Resende JA, Godon JJ, Bonnafous A, Arcuri PB, Silva VL, Otenio MH, Diniz CG. Seasonal Variation on Microbial Community and Methane Production during Anaerobic Digestion of Cattle Manure in Brazil. MICROBIAL ECOLOGY 2016; 71:735-746. [PMID: 26219266 DOI: 10.1007/s00248-015-0647-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 07/09/2015] [Indexed: 05/27/2023]
Abstract
Anaerobic digestion is an alternative method for the treatment of animal manure and wastewater. The anaerobic bioconversion of biomass requires a multi-step biological process, including microorganisms with distinct roles. The diversity and composition of microbial structure in pilot-scale anaerobic digestion operating at ambient temperature in Brazil were studied. Influence of the seasonal and temporal patterns on bacterial and archaeal communities were assessed by studying the variations in density, dynamic and diversity and structure. The average daily biogas produced in the summer and winter months was 18.7 and 16 L day(-1), respectively, and there was no difference in the average methane yield. Quantitative PCR analysis revealed that no differences in abundances and dynamics were found for bacterial communities and the total number of Archaea in different seasons. Analysis of bacterial clone libraries revealed a predominance of Firmicutes (54.5 %/summer and 46.7 %/winter) and Bacteroidetes (31.4 %/summer and 44.4 %/winter). Within the Archaea, the phylum Euryarchaeota was predominant in both digesters. Phylogenetic distribution showed changes in percentage between the phyla identified, but no alterations were recorded in the quality and amount of produced methane or community dynamics. The results may suggest that redundancy of microbial groups may have occurred, pointing to a more complex microbial community in the ecosystem related to this ambient temperature system.
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Affiliation(s)
- Juliana Alves Resende
- Laboratory of Bacterial Physiology and Molecular Genetics, Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, 36.036-900, Juiz de Fora, Minais Gerais, Brazil
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Narbonne, France
| | - Jean-Jacques Godon
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Narbonne, France
| | - Anaïs Bonnafous
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Narbonne, France
| | - Pedro Braga Arcuri
- EMBRAPA Brazilian Agricultural Research Corporation, Secretariat for International Relations, Headquarters, Brasilia, Brazil
| | - Vânia Lúcia Silva
- Laboratory of Bacterial Physiology and Molecular Genetics, Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, 36.036-900, Juiz de Fora, Minais Gerais, Brazil
| | | | - Cláudio Galuppo Diniz
- Laboratory of Bacterial Physiology and Molecular Genetics, Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, 36.036-900, Juiz de Fora, Minais Gerais, Brazil.
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Singh B, Poças-Fonseca MJ, Johri BN, Satyanarayana T. Thermophilic molds: Biology and applications. Crit Rev Microbiol 2016; 42:985-1006. [DOI: 10.3109/1040841x.2015.1122572] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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15
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De Vrieze J, Raport L, Willems B, Verbrugge S, Volcke E, Meers E, Angenent LT, Boon N. Inoculum selection influences the biochemical methane potential of agro-industrial substrates. Microb Biotechnol 2015; 8:776-86. [PMID: 25756301 PMCID: PMC4554466 DOI: 10.1111/1751-7915.12268] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 12/22/2022] Open
Abstract
Obtaining a reliable estimation of the methane potential of organic waste streams in anaerobic digestion, for which a biochemical methane potential (BMP) test is often used, is of high importance. Standardization of this BMP test is required to ensure inter-laboratory repeatability and accuracy of the BMP results. Therefore, guidelines were set out; yet, these do not provide sufficient information concerning origin of and the microbial community in the test inoculum. Here, the specific contribution of the methanogenic community on the BMP test results was evaluated. The biomethane potential of four different substrates (molasses, bio-refinery waste, liquid manure and high-rate activated sludge) was determined by means of four different inocula from full-scale anaerobic digestion plants. A significant effect of the selected inoculum on the BMP result was observed for two out of four substrates. This inoculum effect could be attributed to the abundance of methanogens and a potential inhibiting effect in the inoculum itself, demonstrating the importance of inoculum selection for BMP testing. We recommend the application of granular sludge as an inoculum, because of its higher methanogenic abundance and activity, and protection from bulk solutions, compared with other inocula.
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Affiliation(s)
- Jo De Vrieze
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Linde Raport
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
- InnolabDerbystraat 223, Sint-Denijs-Westrem, 9051, Belgium
| | | | - Silke Verbrugge
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Eveline Volcke
- Department of Biosystems Engineering, Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Erik Meers
- Laboratory of Analytical Chemistry and Applied Biochemistry, Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Largus T Angenent
- Department of Biological and Environmental Engineering, Cornell UniversityIthaca, NY, 14853, USA
| | - Nico Boon
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
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16
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From mesophilic to thermophilic digestion: the transitions of anaerobic bacterial, archaeal, and fungal community structures in sludge and manure samples. Appl Microbiol Biotechnol 2015; 99:10271-82. [DOI: 10.1007/s00253-015-6866-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/16/2015] [Accepted: 07/18/2015] [Indexed: 11/25/2022]
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17
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Sun L, Pope PB, Eijsink VGH, Schnürer A. Characterization of microbial community structure during continuous anaerobic digestion of straw and cow manure. Microb Biotechnol 2015; 8:815-27. [PMID: 26152665 PMCID: PMC4554469 DOI: 10.1111/1751-7915.12298] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 05/13/2015] [Indexed: 01/22/2023] Open
Abstract
Responses of bacterial and archaeal communities to the addition of straw during anaerobic digestion of manure at different temperatures (37°C, 44°C and 52°C) were investigated using five laboratory-scale semi-continuous stirred tank reactors. The results revealed that including straw as co-substrate decreased the species richness for bacteria, whereas increasing the operating temperature decreased the species richness for both archaea and bacteria, and also the evenness of the bacteria. Taxonomic classifications of the archaeal community showed that Methanobrevibacter dominated in the manure samples, while Methanosarcina dominated in all digesters regardless of substrate. Increase of the operating temperature to 52°C led to increased relative abundance of Methanoculleus and Methanobacterium. Among the bacteria, the phyla Firmicutes and Bacteroidetes dominated within all samples. Compared with manure itself, digestion of manure resulted in a higher abundance of an uncultured class WWE1 and lower abundance of Bacilli. Adding straw to the digesters increased the level of Bacteroidia, while increasing the operating temperature decreased the level of this class and instead increased the relative abundance of an uncultured genus affiliated to order MBA08 (Clostridia). A considerable fraction of bacterial sequences could not be allocated to genus level, indicating that novel phylotypes are resident in these communities.
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Affiliation(s)
- Li Sun
- Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, SE-750 07, Uppsala, Sweden
| | - Phillip B Pope
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Vincent G H Eijsink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Anna Schnürer
- Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, SE-750 07, Uppsala, Sweden.,Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
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Kuroda K, Hatamoto M, Nakahara N, Abe K, Takahashi M, Araki N, Yamaguchi T. Community composition of known and uncultured archaeal lineages in anaerobic or anoxic wastewater treatment sludge. MICROBIAL ECOLOGY 2015; 69:586-596. [PMID: 25373332 DOI: 10.1007/s00248-014-0525-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 10/21/2014] [Indexed: 06/04/2023]
Abstract
Microbial systems are widely used to treat different types of wastewater from domestic, agricultural, and industrial sources. Community composition is an important factor in determining the successful performance of microbial treatment systems; however, a variety of uncultured and unknown lineages exist in sludge that requires identification and characterization. The present study examined the archaeal community composition in methanogenic, denitrifying, and nitrogen-/phosphate-removing wastewater treatment sludge by Archaea-specific 16S rRNA gene sequencing analysis using Illumina sequencing technology. Phylotypes belonging to Euryarchaeota, including methanogens, were most abundant in all samples except for nitrogen-/phosphate-removing wastewater treatment sludge. High levels of Deep Sea Hydrothermal Vent Group 6 (DHVEG-6), WSA2, Terrestrial Miscellaneous Euryarchaeotal Group, and Miscellaneous Crenarchaeotic Group were also detected. Interestingly, DHVEG-6 was dominant in nitrogen-/phosphate-removing wastewater treatment sludge, indicating that unclear lineages of Archaea still exist in the anaerobic wastewater treatment sludges. These results reveal a previously unknown diversity of Archaea in sludge that can potentially be exploited for the development of more efficient wastewater treatment strategies.
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Affiliation(s)
- Kyohei Kuroda
- Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1, Kami-tomioka, Nagaoka, Niigata, 940-2188, Japan,
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Gagliano M, Braguglia C, Petruccioli M, Rossetti S. Ecology and biotechnological potential of the thermophilic fermentative Coprothermobacter spp. FEMS Microbiol Ecol 2015; 91:fiv018. [DOI: 10.1093/femsec/fiv018] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2015] [Indexed: 12/29/2022] Open
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20
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Microbial communities involved in biogas production from wheat straw as the sole substrate within a two-phase solid-state anaerobic digestion. Syst Appl Microbiol 2014; 37:590-600. [DOI: 10.1016/j.syapm.2014.10.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 10/07/2014] [Accepted: 10/07/2014] [Indexed: 11/22/2022]
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21
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Yu D, Kurola JM, Lähde K, Kymäläinen M, Sinkkonen A, Romantschuk M. Biogas production and methanogenic archaeal community in mesophilic and thermophilic anaerobic co-digestion processes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2014; 143:54-60. [PMID: 24837280 DOI: 10.1016/j.jenvman.2014.04.025] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 03/05/2014] [Accepted: 04/23/2014] [Indexed: 05/28/2023]
Abstract
Over 258 Mt of solid waste are generated annually in Europe, a large fraction of which is biowaste. Sewage sludge is another major waste fraction. In this study, biowaste and sewage sludge were co-digested in an anaerobic digestion reactor (30% and 70% of total wet weight, respectively). The purpose was to investigate the biogas production and methanogenic archaeal community composition in the anaerobic digestion reactor under meso- (35-37 °C) and thermophilic (55-57 °C) processes and an increasing organic loading rate (OLR, 1-10 kg VS m(-3) d(-1)), and also to find a feasible compromise between waste treatment capacity and biogas production without causing process instability. In summary, more biogas was produced with all OLRs by the thermophilic process. Both processes showed a limited diversity of the methanogenic archaeal community which was dominated by Methanobacteriales and Methanosarcinales (e.g. Methanosarcina) in both meso- and thermophilic processes. Methanothermobacter was detected as an additional dominant genus in the thermophilic process. In addition to operating temperatures, the OLRs, the acetate concentration, and the presence of key substrates like propionate also affected the methanogenic archaeal community composition. A bacterial cell count 6.25 times higher than archaeal cell count was observed throughout the thermophilic process, while the cell count ratio varied between 0.2 and 8.5 in the mesophilic process. This suggests that the thermophilic process is more stable, but also that the relative abundance between bacteria and archaea can vary without seriously affecting biogas production.
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Affiliation(s)
- D Yu
- University of Helsinki, Department of Environmental Sciences, Niemenkatu 73, 15140 Lahti, Finland
| | - J M Kurola
- University of Helsinki, Department of Environmental Sciences, Niemenkatu 73, 15140 Lahti, Finland
| | - K Lähde
- HAMK University of Applied Sciences, P.O. Box 230, 13101 Hämeenlinna, Finland
| | - M Kymäläinen
- HAMK University of Applied Sciences, P.O. Box 230, 13101 Hämeenlinna, Finland
| | - A Sinkkonen
- University of Helsinki, Department of Environmental Sciences, Niemenkatu 73, 15140 Lahti, Finland
| | - M Romantschuk
- University of Helsinki, Department of Environmental Sciences, Niemenkatu 73, 15140 Lahti, Finland.
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22
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Kohrs F, Heyer R, Magnussen A, Benndorf D, Muth T, Behne A, Rapp E, Kausmann R, Heiermann M, Klocke M, Reichl U. Sample prefractionation with liquid isoelectric focusing enables in depth microbial metaproteome analysis of mesophilic and thermophilic biogas plants. Anaerobe 2014; 29:59-67. [DOI: 10.1016/j.anaerobe.2013.11.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 11/22/2013] [Accepted: 11/25/2013] [Indexed: 12/20/2022]
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23
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Nettmann E, Fröhling A, Heeg K, Klocke M, Schlüter O, Mumme J. Development of a flow-fluorescence in situ hybridization protocol for the analysis of microbial communities in anaerobic fermentation liquor. BMC Microbiol 2013; 13:278. [PMID: 24304697 PMCID: PMC4235175 DOI: 10.1186/1471-2180-13-278] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 11/21/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The production of bio-methane from renewable raw material is of high interest because of the increasing scarcity of fossil fuels. The process of biomethanation is based on the inter- and intraspecific metabolic activity of a highly diverse and dynamic microbial community. The community structure of the microbial biocenosis varies between different biogas reactors and the knowledge about these microbial communities is still fragmentary. However, up to now no approaches are available allowing a fast and reliable access to the microbial community structure. Hence, the aim of this study was to originate a Flow-FISH protocol, namely a combination of flow cytometry and fluorescence in situ hybridization, for the analysis of the metabolically active microorganisms in biogas reactor samples. With respect to the heterogenic texture of biogas reactor samples and to collect all cells including those of cell aggregates and biofilms the development of a preceding purification procedure was indispensable. RESULTS Six different purification procedures with in total 29 modifications were tested. The optimized purification procedure combines the use of the detergent sodium hexametaphosphate with ultrasonic treatment and a final filtration step. By this treatment, the detachment of microbial cells from particles as well as the disbandment of cell aggregates was obtained at minimized cell loss. A Flow-FISH protocol was developed avoiding dehydration and minimizing centrifugation steps. In the exemplary application of this protocol on pure cultures as well as biogas reactor samples high hybridization rates were achieved for commonly established domain specific oligonucleotide probes enabling the specific detection of metabolically active bacteria and archaea. Cross hybridization and autofluorescence effects could be excluded by the use of a nonsense probe and negative controls, respectively. CONCLUSIONS The approach described in this study enables for the first time the analysis of the metabolically active fraction of the microbial communities within biogas reactors by Flow-FISH.
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Affiliation(s)
- Edith Nettmann
- APECS junior research group, Leibniz Institute for Agricultural Engineering, Max-Eyth-Allee 100, 14469 Potsdam, Germany.
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