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Magalhães CP, Alves JI, Duber A, Oleskowicz-Popiel P, Stams AJM, Cavaleiro AJ. Metabolic versatility of anaerobic sludge towards platform chemical production from waste glycerol. Appl Microbiol Biotechnol 2024; 108:419. [PMID: 39012392 PMCID: PMC11252210 DOI: 10.1007/s00253-024-13248-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 06/24/2024] [Accepted: 06/27/2024] [Indexed: 07/17/2024]
Abstract
Waste glycerol is produced in excess by several industries, such as during biodiesel production. In this work, the metabolic versatility of anaerobic sludge was explored towards waste glycerol valorization. By applying different environmental (methanogenic and sulfate-reducing) conditions, three distinct microbial cultures were obtained from the same inoculum (anaerobic granular sludge), with high microbial specialization, within three different phyla (Thermodesulfobacteriota, Euryarchaeota and Pseudomonadota). The cultures are capable of glycerol conversion through different pathways: (i) glycerol conversion to methane by a bacterium closely related to Solidesulfovibrio alcoholivorans (99.8% 16S rRNA gene identity), in syntrophic relationship with Methanofollis liminatans (98.8% identity), (ii) fermentation to propionate by Propionivibrio pelophilus strain asp66 (98.6% identity), with a propionate yield of 0.88 mmol mmol-1 (0.71 mg mg-1) and a propionate purity of 80-97% and (iii) acetate production coupled to sulfate reduction by Desulfolutivibrio sulfoxidireducens (98.3% identity). In conclusion, starting from the same inoculum, we could drive the metabolic and functional potential of the microbiota towards the formation of several valuable products that can be used in industrial applications or as energy carriers. KEY POINTS: Versatility of anaerobic cultures was explored for waste glycerol valorization Different environmental conditions lead to metabolic specialization Biocommodities such as propionate, acetate and methane were produced.
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Affiliation(s)
- Carla P Magalhães
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
| | - Joana I Alves
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
- LABBELS - Associate Laboratory, Braga/Guimarães, Portugal
| | - Anna Duber
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Poznan, Poland
| | - Piotr Oleskowicz-Popiel
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Poznan, Poland
| | - Alfons J M Stams
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands
| | - Ana J Cavaleiro
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal.
- LABBELS - Associate Laboratory, Braga/Guimarães, Portugal.
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2
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A novel nitrogen-fixing bacterium, Propionivibrio soli sp. nov. isolated from paddy soil. Arch Microbiol 2023; 205:68. [PMID: 36662302 DOI: 10.1007/s00203-023-03413-2] [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: 11/14/2022] [Revised: 01/04/2023] [Accepted: 01/10/2023] [Indexed: 01/21/2023]
Abstract
A facultative anaerobic nitrogen-fixing bacterium, designated SG131T, was isolated from paddy soil. Strain SG131T showed high 16S rRNA gene sequence similarities with type strains Propionivibrio limicola DSM 6832T (96.9%), Propionivibrio pelophilus asp 66T (96.0%) and Propionivibrio dicarboxylicus DSM 5885T (95.7%). The phylogenetic trees (based on 16S rRNA gene sequences and 120 conserved genes from genomes, respectively) indicated that strain SG131T clustered with members of the genus Propionivibrio. Growth of strain SG131T was observed at 25-40 °C, pH 5.5-10.5 and 0-0.5% (w/v) NaCl. The quinone was Q-7, and the main fatty acids were C16:1 ω6c and/or C16:1 ω7c (25.9%), C16:0 (23.3%), C17:0-cyclo (11.7%), C12:0 (6.0%) and C17:0 (5.9%). The genomic DNA G + C content of strain SG131T was 60.3%. The average nucleotide identity (ANI) values between strain SG131T and its most closely related species P. limicola DSM 6832T, P. pelophilus DSM 12018T and P. dicarboxylicus DSM 5885T were 74.4%, 74.9% and 75.6%, respectively. The digital DNA-DNA hybridization (dDDH) values between strain SG131T and its most closely related species P. limicola DSM 6832T, P. pelophilus DSM 12018T and P. dicarboxylicus DSM 5885T were 19.9%, 20.6% and 20.5%, respectively. All these values were lower than the recommended species delineation thresholds of ANI (95-96%) and dDDH (70%). Strain SG131T possessed core genes (nifHDK) of nitrogen fixation and was confirmed its nitrogen-fixing ability by the ARA method. According to the above-described analysis, strain SG131T represents a novel species of the genus Propionivibrio, for which the name Propionivibrio soli sp. nov. is proposed. The type strain is SG131T (= GDMCC 1.3313T = JCM 35595T).
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Battaglia-Brunet F, Naveau A, Cary L, Bueno M, Briais J, Charron M, Joulian C, Thouin H. Biogeochemical behaviour of geogenic As in a confined aquifer of the Sologne region, France. CHEMOSPHERE 2022; 304:135252. [PMID: 35691389 DOI: 10.1016/j.chemosphere.2022.135252] [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: 02/09/2022] [Revised: 05/28/2022] [Accepted: 06/03/2022] [Indexed: 06/15/2023]
Abstract
Arsenic (As) is one of the main toxic elements of geogenic origin that impact groundwater quality and human health worldwide. In some groundwater wells of the Sologne region (Val de Loire, France), drilled in a confined aquifer, As concentrations exceed the European drinking water standard (10 μg L-1). The monitoring of one of these drinking water wells showed As concentrations in the range 20-25 μg L-1. The presence of dissolved iron (Fe), low oxygen concentration and traces of ammonium indicated reducing conditions. The δ34SSO4 was anticorrelated with sulphate concentration. Drilling allowed to collect detrital material corresponding to a Miocene floodplain and crevasse splay with preserved plant debris. The level that contained the highest total As concentration was a silty-sandy clay containing 26.9 mg kg-1 As. The influence of alternating redox conditions on the behaviour of As was studied by incubating this material with site groundwater, in biotic or inhibited bacterial activities conditions, without synthetic organic nutrient supply, in presence of H2 during the reducing periods. The development of both AsV-reducing and AsIII-oxidising microorganisms in biotic conditions was evidenced. At the end of the reducing periods, total As concentration strongly increased in biotic conditions. The microflora influenced As speciation, released Fe and consumed nitrate and sulphate in the water phase. Microbial communities observed in groundwater samples strongly differed from those obtained at the end of the incubation experiment, this result being potentially related to influence of the sediment compartment and to different physico-chemical conditions. However, both included major Operating Taxonomic Units (OTU) potentially involved in Fe and S biogeocycles. Methanogens emerged in the incubated sediment presenting the highest solubilised As and Fe. Results support the hypothesis of in-situ As mobilisation and speciation mediated by active biogeochemical processes.
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Affiliation(s)
- Fabienne Battaglia-Brunet
- BRGM, F-45060, Orléans, France; ISTO, UMR7327, Université D'Orléans, CNRS, BRGM, F-45071, Orléans, France.
| | - Aude Naveau
- Institut de Chimie des Milieux et Matériaux de Poitiers (IC2MP), Université de Poitiers/CNRS, UMR 7285, Rue Michel Brunet, F-86022, Poitiers Cedex, France
| | | | - Maïté Bueno
- Universite de Pau et des Pays de L'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et de Physicochimie pour L'Environnement et Les Matériaux-IPREM, UMR5254, 64000, Pau, France
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Farrer AG, Wright SL, Skelly E, Eisenhofer R, Dobney K, Weyrich LS. Effectiveness of decontamination protocols when analyzing ancient DNA preserved in dental calculus. Sci Rep 2021; 11:7456. [PMID: 33811235 PMCID: PMC8018977 DOI: 10.1038/s41598-021-86100-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 02/26/2021] [Indexed: 02/01/2023] Open
Abstract
Ancient DNA analysis of human oral microbial communities within calcified dental plaque (calculus) has revealed key insights into human health, paleodemography, and cultural behaviors. However, contamination imposes a major concern for paleomicrobiological samples due to their low endogenous DNA content and exposure to environmental sources, calling into question some published results. Decontamination protocols (e.g. an ethylenediaminetetraacetic acid (EDTA) pre-digestion or ultraviolet radiation (UV) and 5% sodium hypochlorite immersion treatments) aim to minimize the exogenous content of the outer surface of ancient calculus samples prior to DNA extraction. While these protocols are widely used, no one has systematically compared them in ancient dental calculus. Here, we compare untreated dental calculus samples to samples from the same site treated with four previously published decontamination protocols: a UV only treatment; a 5% sodium hypochlorite immersion treatment; a pre-digestion in EDTA treatment; and a combined UV irradiation and 5% sodium hypochlorite immersion treatment. We examine their efficacy in ancient oral microbiota recovery by applying 16S rRNA gene amplicon and shotgun sequencing, identifying ancient oral microbiota, as well as soil and skin contaminant species. Overall, the EDTA pre-digestion and a combined UV irradiation and 5% sodium hypochlorite immersion treatment were both effective at reducing the proportion of environmental taxa and increasing oral taxa in comparison to untreated samples. This research highlights the importance of using decontamination procedures during ancient DNA analysis of dental calculus to reduce contaminant DNA.
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Affiliation(s)
- Andrew G. Farrer
- grid.1010.00000 0004 1936 7304Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia Australia
| | - Sterling L. Wright
- grid.29857.310000 0001 2097 4281The Department of Anthropology, The Pennsylvania State University, University Park, PA USA
| | - Emily Skelly
- grid.1010.00000 0004 1936 7304Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia Australia
| | - Raphael Eisenhofer
- grid.1010.00000 0004 1936 7304Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia Australia ,grid.1010.00000 0004 1936 7304Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, University of Adelaide, Adelaide, South Australia Australia
| | - Keith Dobney
- grid.1013.30000 0004 1936 834XDepartment of Archaeology, University of Sydney, Sydney, NSW Australia
| | - Laura S. Weyrich
- grid.1010.00000 0004 1936 7304Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia Australia ,grid.29857.310000 0001 2097 4281The Department of Anthropology, The Pennsylvania State University, University Park, PA USA ,grid.1010.00000 0004 1936 7304Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, University of Adelaide, Adelaide, South Australia Australia ,grid.29857.310000 0001 2097 4281The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, PA USA
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Zhou C, Miao T, Jiang L, Zhang H, Zhang Y, Zhang X. Conditions that promote the formation of black bloom in aquatic microcosms and its effects on sediment bacteria related to iron and sulfur cycling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141869. [PMID: 32882542 DOI: 10.1016/j.scitotenv.2020.141869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/16/2020] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
Black bloom occurs frequently in eutrophic waters. We investigated the conditions promoted the formation of black bloom via in-situ measurement in two aquatic microcosms and the effects of black bloom on the bacterial community composition. Although larger changes in dissolved oxygen (DO) were detected in the Hydrilla verticillata-dominated microcosm over the 90-day simulation, black bloom occurred more readily in the phytoplankton-dominated than macrophyte-dominated microcosm under conditions of O2 depletion and temperature above 30 °C. The sediment bacterial community composition shifted after black bloom; the relative abundance of Thiobacillus and Sideroxydans, which oxidize iron (Fe) and sulfur (S), decreased by 47% and 48%, respectively, in the phytoplankton-dominated microcosm and by 18% and 20% in the macrophyte-dominated microcosm. By contrast, Desulfatiglans increased by 13% and 19%, respectively, after black bloom. Furthermore, inter-taxa correlations remarkably changed according to co-occurrence network analysis. Thirty-six different taxa from the phylum to the genus level were identified as biomarkers of sediments collected before and after the black bloom event. Most of these biomarkers are related to Fe/S cycling in aquatic ecosystems.
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Affiliation(s)
- Chi Zhou
- Hubei Water Resources Research Institute, Hubei Water Resources and Hydropower Science and Technology Promotion Center, Wuhan 430070, PR China
| | - Teng Miao
- Hubei Water Resources Research Institute, Hubei Water Resources and Hydropower Science and Technology Promotion Center, Wuhan 430070, PR China
| | - Lai Jiang
- Hubei Water Resources Research Institute, Hubei Water Resources and Hydropower Science and Technology Promotion Center, Wuhan 430070, PR China
| | - Hang Zhang
- Hubei Water Resources Research Institute, Hubei Water Resources and Hydropower Science and Technology Promotion Center, Wuhan 430070, PR China
| | - Yi Zhang
- Hubei Water Resources Research Institute, Hubei Water Resources and Hydropower Science and Technology Promotion Center, Wuhan 430070, PR China
| | - Xu Zhang
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, PR China.
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Pang H, Xin X, He J, Cui B, Guo D, Liu S, Yan Z, Liu C, Wang X, Nan J. Effect of NaCl Concentration on Microbiological Properties in NaCl Assistant Anaerobic Fermentation: Hydrolase Activity and Microbial Community Distribution. Front Microbiol 2020; 11:589222. [PMID: 33162967 PMCID: PMC7581909 DOI: 10.3389/fmicb.2020.589222] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/14/2020] [Indexed: 01/27/2023] Open
Abstract
Previous studies have demonstrated that sludge hydrolysis and short-chain fatty acids (SCFAs) production were improved through NaCl assistant anaerobic fermentation. However, the effect of NaCl concentrations on hydrolase activity and microbial community structure was rarely reported. In this study, it was found that α-glucosidase activity and some carbohydrate-degrading bacteria were inhibited in NaCl tests, owing to their vulnerability to high NaCl concentration. Correspondingly, the microbial community richness and diversity were reduced compared with the control test, while the evenness was not affected by NaCl concentration. By contrast, the protease activity was increased in the presence of NaCl and reached the highest activity at the NaCl concentration of 20 g/L. The protein-degrading and SCFAs-producing bacteria (e.g., Clostridium algidicarnis and Proteiniclasticum) were enriched in the presence of NaCl, which were salt-tolerant.
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Affiliation(s)
- Heliang Pang
- School of Environment, Harbin Institute of Technology, Harbin, China
| | - Xiaodong Xin
- Department of Environmental Science and Engineering, Huaqiao University, Xiamen, China
| | - Junguo He
- School of Civil Engineering, Guangzhou University, Guangzhou, China
| | - Baihui Cui
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore, Singapore
| | - Dabin Guo
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China.,Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore, Singapore
| | - Shiming Liu
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore, Singapore
| | - Zhongsen Yan
- College of Civil Engineering, Fuzhou University, Fuzhou, China
| | - Chong Liu
- Frog Biotechnology Co., LTD, Harbin, China
| | - Xinyu Wang
- School of Environment, Harbin Institute of Technology, Harbin, China
| | - Jun Nan
- School of Environment, Harbin Institute of Technology, Harbin, China
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Watanabe K, Morohoshi S, Kunihiro T, Ishii Y, Takayasu L, Ogata Y, Shindo C, Suda W. Fluviibacter phosphoraccumulans gen. nov., sp. nov., a polyphosphate-accumulating bacterium of Fluviibacteraceae fam. nov., isolated from surface river water. Int J Syst Evol Microbiol 2020; 70:5551-5560. [PMID: 32915122 DOI: 10.1099/ijsem.0.004446] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Three aerobic, Gram-stain-negative, non-motile, rod-shaped bacteria, designated as strains SHINM1T, ICHIJ1 and ICHIAU1, were isolated from surface river water (Saitama Prefecture, Japan). Phylogenetic analyses based on 16S rRNA and 40 marker gene sequences revealed that the strains formed a distinct phylogenetic lineage within the order Rhodocyclales. The three strains shared 100 % 16S rRNA gene similarity. Growth occurred at 15-30 °C and pH 6.0-9.5, but not in the presence of ≥1.0 % (w/v) NaCl. The isolates stained positive for intracellular polyphosphate granules. The major cellular fatty acids were C16 : 0, summed feature 2 (C12 : 1 aldehyde and/or iso-C16 : 1 I and/or C14 : 0 3-OH), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The major polar lipids were phosphatidylethanolamine and an unidentified phospholipid. The predominant quinone system of strain SHINM1T was ubiquinone-8 and its DNA G+C content was 56.7 mol%. Genome sequencing of the three isolates revealed a genome size of 2.29-2.43 Mbp and average nucleotide identity by orthology values of ≥98.9 %. Based on the results of phenotypic and phylogenetic analyses, strains SHINM1T, ICHIJ1 and ICHIAU1 represent a novel species of a new genus, for which the name Fluviibacter phosphoraccumulans gen. nov., sp. nov. is proposed, within a new family, Fluviibacteraceae fam. nov. of the order Rhodocyclales. The type strain is SHINM1T (=JCM 32071T=NCIMB 15105T).
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Affiliation(s)
- Keiji Watanabe
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115, Japan
| | - Sho Morohoshi
- TechnoSuruga Laboratory Co., Ltd, 330 Nagasaki, Shimizu-ku, Shizuoka-shi, Shizuoka 424-0065, Japan
| | - Tadao Kunihiro
- TechnoSuruga Laboratory Co., Ltd, 330 Nagasaki, Shimizu-ku, Shizuoka-shi, Shizuoka 424-0065, Japan
| | - Yuichi Ishii
- Tokyo Metropolitan Research Institute for Environmental Protection, 1-7-5 Shinsuna, Koto-ku, Tokyo 136-0075, Japan
| | - Lena Takayasu
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
- Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yusuke Ogata
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Chie Shindo
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Wataru Suda
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
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Liechty Z, Santos-Medellín C, Edwards J, Nguyen B, Mikhail D, Eason S, Phillips G, Sundaresan V. Comparative Analysis of Root Microbiomes of Rice Cultivars with High and Low Methane Emissions Reveals Differences in Abundance of Methanogenic Archaea and Putative Upstream Fermenters. mSystems 2020; 5:e00897-19. [PMID: 32071162 PMCID: PMC7029222 DOI: 10.1128/msystems.00897-19] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 01/22/2020] [Indexed: 02/01/2023] Open
Abstract
Rice cultivation worldwide accounts for ∼7 to 17% of global methane emissions. Methane cycling in rice paddies is a microbial process not only involving methane producers (methanogens) and methane metabolizers (methanotrophs) but also other microbial taxa that affect upstream processes related to methane metabolism. Rice cultivars vary in their rates of methane emissions, but the influence of rice genotypes on methane cycling microbiota has been poorly characterized. Here, we profiled the rhizosphere, rhizoplane, and endosphere microbiomes of a high-methane-emitting cultivar (Sabine) and a low-methane-emitting cultivar (CLXL745) throughout the growing season to identify variations in the archaeal and bacterial communities relating to methane emissions. The rhizosphere of the high-emitting cultivar was enriched in methanogens compared to that in the low emitter, whereas the relative abundances of methanotrophs between the cultivars were not significantly different. Further analysis of cultivar-sensitive taxa identified families enriched in the high emitter that are associated with methanogenesis-related processes. The high emitter had greater relative abundances of sulfate-reducing and iron-reducing taxa which peak earlier in the season than methanogens and are necessary to lower soil oxidation reduction potential before methanogenesis can occur. The high emitter also had a greater abundance of fermentative taxa which produce methanogenesis precursors (acetate, CO2, and H2). Furthermore, the high emitter was enriched in taxa related to acetogenesis which compete with methanogens for CO2 and H2 These taxa were enriched in a spatio-specific manner and reveal a complex network of microbial interactions on which plant genotype-dependent factors can act to affect methanogenesis and methane emissions.IMPORTANCE Rice cultivation is a major source of anthropogenic emissions of methane, a greenhouse gas with a potentially severe impact on climate change. Emission variation between rice cultivars suggests the feasibility of breeding low-emission rice, but there is a limited understanding of how genotypes affect the microbiota involved in methane cycling. Here, we show that the root microbiome of the high-emitting cultivar is enriched both in methanogens and in taxa associated with fermentation, iron, and sulfate reduction and acetogenesis, processes that support methanogenesis. Understanding how cultivars affect microbes with methanogenesis-related functions is vital for understanding the genetic basis for methane emission in rice and can aid in the development of breeding programs that reduce the environmental impact of rice cultivation.
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Affiliation(s)
- Zachary Liechty
- Department of Plant Biology, University of California, Davis, Davis, California, USA
| | | | - Joseph Edwards
- Department of Plant Biology, University of California, Davis, Davis, California, USA
| | - Bao Nguyen
- Department of Plant Biology, University of California, Davis, Davis, California, USA
| | - David Mikhail
- Department of Plant Biology, University of California, Davis, Davis, California, USA
| | - Shane Eason
- Department of Agriculture, Arkansas State University, Jonesboro, Arkansas, USA
| | - Gregory Phillips
- Department of Agriculture, Arkansas State University, Jonesboro, Arkansas, USA
| | - Venkatesan Sundaresan
- Department of Plant Biology, University of California, Davis, Davis, California, USA
- Department of Plant Sciences, University of California, Davis, Davis, California, USA
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Ge Z, Wei D, Zhang J, Hu J, Liu Z, Li R. Natural pyrite to enhance simultaneous long-term nitrogen and phosphorus removal in constructed wetland: Three years of pilot study. WATER RESEARCH 2019; 148:153-161. [PMID: 30359945 DOI: 10.1016/j.watres.2018.10.037] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Revised: 10/12/2018] [Accepted: 10/13/2018] [Indexed: 06/08/2023]
Abstract
The searches for suitable substrates with high capacity for phosphorus (P) removal and promoting denitrification for enhancing nitrogen (N) removal have been a key work in constructed wetlands (CWs) research in the past several decades. But few substrates enhancing simultaneous long-term N and P removal in CWs have been found before. In this study, two subsurface flow pilot-scale wetlands using natural pyrite and limestone as substrates were constructed. After 3 year of operation, we found that pyrite had no negative effects on growth of reeds, removals of chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N), but enhanced long-term total nitrogen (TN) and total phosphorus (TP) removals in constructed wetland. In the three years, the average TP and TN removals of pyrite constructed wetland (PCW) were 87.7 ± 14.2% with 0.25 ± 0.20 mg/L of average effluent TP and 69.4 ± 21.4% with 4.0 ± 3.2 mg/L of average effluent TN, respectively. The main P form in the PCW was (Fe + Al)-bound P. The mechanisms of the PCW with enhanced simultaneous long-term N and P removals were anaerobic and aerobic oxidations of pyrite. The main bacteria were Anaeromyxobacter (4.9%), Ramlibacter (4.8%), Defluviicoccus (4.2%), Azoarcus (3.7%), Geobacter (3.4%), and they were highly related to anaerobic and aerobic oxidation of pyrite in the PCW.
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Affiliation(s)
- Zhibin Ge
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163# Xianlin Ave., Nanjing, Jiangsu 210023, PR China
| | - Dongyang Wei
- South China Institute of Environmental Sciences, MEP, Guangzhou 510655, China
| | - Jing Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163# Xianlin Ave., Nanjing, Jiangsu 210023, PR China
| | - Junsong Hu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163# Xianlin Ave., Nanjing, Jiangsu 210023, PR China
| | - Zhuo Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163# Xianlin Ave., Nanjing, Jiangsu 210023, PR China
| | - Ruihua Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163# Xianlin Ave., Nanjing, Jiangsu 210023, PR China.
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10
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Wong PY, Cheng KY, Krishna KCB, Kaksonen AH, Sutton DC, Ginige MP. Improvement of carbon usage for phosphorus recovery in EBPR-r and the shift in microbial community. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 218:569-578. [PMID: 29709825 DOI: 10.1016/j.jenvman.2018.03.130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 03/09/2018] [Accepted: 03/31/2018] [Indexed: 06/08/2023]
Abstract
Enhanced biological phosphorus removal and recovery (EBPR-r) is a biofilm process that makes use of polyphosphate accumulating organisms (PAOs) to remove and recover phosphorus (P) from wastewater. The original process was inefficient, as indicated by the low P-release to carbon (C)-uptake (Prel/Cupt) molar ratio of the biofilm. This study successfully validated a strategy to improve the Prel/Cupt ratio by at least 3-fold. With an unchanged supply of carbon in the recovery stream, an increase in the hydraulic loading in stages I, II and III (7.2, 14.4 and 21.6 L, respectively) resulted in a 43% increase in the Prel/Cupt ratio (0.069, 0.076 and 0.103, respectively). The ratio further increased by 150% (from 0.103 to 0.255) when the duration of the P uptake period was increased from 4 h (stage III) to 10 h (stage IV). Canonical correspondence analysis showed that, correlated to the 3-fold increase in the Prel/Cupt ratio, there was an increase in the abundance of PAOs ("Candidatus Accumulibacter" Clade IIA) and a decrease in the occurrence of glycogen accumulating organisms (GAOs) (family Sinobacteraceae). However, the four stage operation impaired denitrification, resulting in a 5-fold reduction in the Nden/Pupt ratio. The decline in denitrification was consistent with a decrease in the abundance of denitrifiers including denitrifying PAOs (family Comamonadaceae and "Candidatus Accumulibacter" Clade IA). Overall, a strategy to facilitate more efficient use of carbon was validated, enabling a 3-fold carbon saving for P recovery. The new process enabled up to 80% of the wastewater P to be captured in a P-enriched stream (>90 mg/L) with a single uptake/release cycle of recovery.
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Affiliation(s)
- Pan Yu Wong
- Land and Water - CSIRO, 147 Underwood Avenue, Floreat, WA 6014, Australia; School of Biomedial Sciences, University of Western Australia, Nedlands, WA 6009, Australia
| | - Ka Yu Cheng
- Land and Water - CSIRO, 147 Underwood Avenue, Floreat, WA 6014, Australia; School of Engineering and Information Technology, Murdoch University, WA 6150, Australia
| | - K C Bal Krishna
- School of Computing Engineering and Mathematics, Western Sydney University, Kingswood, NSW 2751, Australia
| | - Anna H Kaksonen
- Land and Water - CSIRO, 147 Underwood Avenue, Floreat, WA 6014, Australia; School of Biomedial Sciences, University of Western Australia, Nedlands, WA 6009, Australia
| | - David C Sutton
- School of Biomedial Sciences, University of Western Australia, Nedlands, WA 6009, Australia
| | - Maneesha P Ginige
- Land and Water - CSIRO, 147 Underwood Avenue, Floreat, WA 6014, Australia.
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11
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Dykstra CM, Pavlostathis SG. Methanogenic Biocathode Microbial Community Development and the Role of Bacteria. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:5306-5316. [PMID: 28368570 DOI: 10.1021/acs.est.6b04112] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The cathode microbial community of a methanogenic bioelectrochemical system (BES) is key to the efficient conversion of carbon dioxide (CO2) to methane (CH4) with application to biogas upgrading. The objective of this study was to compare the performance and microbial community composition of a biocathode inoculated with a mixed methanogenic (MM) culture to a biocathode inoculated with an enriched hydrogenotrophic methanogenic (EHM) culture, developed from the MM culture following pre-enrichment with H2 and CO2 as the only externally supplied electron donor and carbon source, respectively. Using an adjacent Ag/AgCl reference electrode, biocathode potential was poised at -0.8 V (versus SHE) using a potentiostat, with the bioanode acting as the counter electrode. When normalized to cathode biofilm biomass, the methane production in the MM- and EHM-biocathode was 0.153 ± 0.010 and 0.586 ± 0.029 mmol CH4/mg biomass-day, respectively. This study showed that H2/CO2 pre-enriched inoculum enhanced biocathode CH4 production, although the archaeal communities in both biocathodes converged primarily (86-100%) on a phylotype closely related to Methanobrevibacter arboriphilus. The bacterial community of the MM-biocathode was similar to that of the MM inoculum but was enriched in Spirochaetes and other nonexoelectrogenic, fermentative Bacteria. In contrast, the EHM-biocathode bacterial community was enriched in Proteobacteria, exoelectrogens, and putative producers of electron shuttle mediators. Similar biomass levels were detected in the MM- and EHM-biocathodes. Thus, although the archaeal communities were similar in the two biocathodes, the difference in bacterial community composition was likely responsible for the 3.8-fold larger CH4 production rate observed in the EHM-biocathode. Roles for abundant OTUs identified in the biofilm and inoculum cultures were highlighted on the basis of previous reports.
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Affiliation(s)
- Christy M Dykstra
- School of Civil and Environmental Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
| | - Spyros G Pavlostathis
- School of Civil and Environmental Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
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12
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Liu CT, Lin SY, Hameed A, Liu YC, Hsu YH, Wong WT, Tseng CH, Lur HS, Young CC. Oryzomicrobium terrae gen. nov., sp. nov., of the family Rhodocyclaceae isolated from paddy soil. Int J Syst Evol Microbiol 2017; 67:183-189. [DOI: 10.1099/ijsem.0.001565] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Chi-Te Liu
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan, ROC
- Institute of Biotechnology, National Taiwan University, Taiwan, ROC
| | - Shih-Yao Lin
- Department of Soil and Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Asif Hameed
- Department of Soil and Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan, ROC
| | - You-Cheng Liu
- Department of Soil and Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Yi-Han Hsu
- Department of Soil and Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Wai-Tak Wong
- Department of Agronomy, National Taiwan University, Taipei, Taiwan, ROC
| | - Ching-Han Tseng
- Institute of Biotechnology, National Taiwan University, Taipei, Taiwan, ROC
| | - Huu-Sheng Lur
- Department of Agronomy, National Taiwan University, Taipei, Taiwan, ROC
| | - Chiu-Chung Young
- Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
- Department of Soil and Environmental Sciences, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan, ROC
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13
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Albertsen M, McIlroy SJ, Stokholm-Bjerregaard M, Karst SM, Nielsen PH. "Candidatus Propionivibrio aalborgensis": A Novel Glycogen Accumulating Organism Abundant in Full-Scale Enhanced Biological Phosphorus Removal Plants. Front Microbiol 2016; 7:1033. [PMID: 27458436 PMCID: PMC4930944 DOI: 10.3389/fmicb.2016.01033] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 06/20/2016] [Indexed: 01/16/2023] Open
Abstract
Enhanced biological phosphorus removal (EBPR) is widely used to remove phosphorus from wastewater. The process relies on polyphosphate accumulating organisms (PAOs) that are able to take up phosphorus in excess of what is needed for growth, whereby phosphorus can be removed from the wastewater by wasting the biomass. However, glycogen accumulating organisms (GAOs) may reduce the EBPR efficiency as they compete for substrates with PAOs, but do not store excessive amounts of polyphosphate. PAOs and GAOs are thought to be phylogenetically unrelated, with the model PAO being the betaproteobacterial “Candidatus Accumulibacter phosphatis” (Accumulibacter) and the model GAO being the gammaproteobacterial “Candidatus Competibacter phosphatis”. Here, we report the discovery of a GAO from the genus Propionivibrio, which is closely related to Accumulibacter. Propionivibrio sp. are targeted by the canonical fluorescence in situ hybridization probes used to target Accumulibacter (PAOmix), but do not store excessive amounts of polyphosphate in situ. A laboratory scale reactor, operated to enrich for PAOs, surprisingly contained co-dominant populations of Propionivibrio and Accumulibacter. Metagenomic sequencing of multiple time-points enabled recovery of near complete population genomes from both genera. Annotation of the Propionivibrio genome confirmed their potential for the GAO phenotype and a basic metabolic model is proposed for their metabolism in the EBPR environment. Using newly designed fluorescence in situ hybridization (FISH) probes, analyses of full-scale EBPR plants revealed that Propionivibrio is a common member of the community, constituting up to 3% of the biovolume. To avoid overestimation of Accumulibacter abundance in situ, we recommend the use of the FISH probe PAO651 instead of the commonly applied PAOmix probe set.
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Affiliation(s)
- Mads Albertsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University Aalborg, Denmark
| | - Simon J McIlroy
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University Aalborg, Denmark
| | - Mikkel Stokholm-Bjerregaard
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg UniversityAalborg, Denmark; Krüger A/SAalborg, Denmark
| | - Søren M Karst
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University Aalborg, Denmark
| | - Per H Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University Aalborg, Denmark
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14
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Mikkelson KM, Homme CL, Li D, Sharp JO. Propane biostimulation in biologically activated carbon (BAC) selects for bacterial clades adept at degrading persistent water pollutants. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2015; 17:1405-1414. [PMID: 26154499 DOI: 10.1039/c5em00212e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Biologically activated carbon (BAC) can be used in both municipal water and hazardous waste remediation applications to enhance contaminant attenuation in water; however, questions remain about how selective pressures can be applied to increase the capabilities of microbial communities to attenuate recalcitrant contaminants. Here we utilized flow-through laboratory columns seeded with municipally derived BAC and exposed to water from a local drinking water facility to query how propane biostimulation impacts resident microorganisms. Ecological analyses using high throughput phylogenetic sequencing revealed that while propane did not increase the total number of microbiological species, it did select for bacterial communities that were distinct from those without propane. Temporal extractions demonstrated that microbial succession was rapid and established in approximately 2 months. A higher density of propane monooxygenase genes and bacterial clades including the Pelosinus and Dechloromonas genera suggest an enhanced potential for the degradation of persistent water pollutants in propane-stimulated systems. However, the ecological selective pressure was exhausted in less than 15 cm of transit in this flow-through scenario (25 hour retention) indicating a pronounced zonation that could limit the size of a biostimulated zone and require physical mixing, hydraulic manipulation, or other strategies to increase the spatial impact of biostimulation in flow-through scenarios.
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Affiliation(s)
- Kristin M Mikkelson
- ReNUWit Engineering Research Center, Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, USA.
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15
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Cai H, Jiang H, Krumholz LR, Yang Z. Bacterial community composition of size-fractioned aggregates within the phycosphere of cyanobacterial blooms in a eutrophic freshwater lake. PLoS One 2014; 9:e102879. [PMID: 25144467 PMCID: PMC4140718 DOI: 10.1371/journal.pone.0102879] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 06/24/2014] [Indexed: 11/18/2022] Open
Abstract
Bacterial community composition of different sized aggregates within the Microcystis cyanobacterial phycosphere were determined during summer and fall in Lake Taihu, a eutrophic lake in eastern China. Bloom samples taken in August and September represent healthy bloom biomass, whereas samples from October represent decomposing bloom biomass. To improve our understanding of the complex interior structure in the phycosphere, bloom samples were separated into large (>100 µm), medium (10-100 µm) and small (0.2-10 µm) size aggregates. Species richness and library coverage indicated that pyrosequencing recovered a large bacterial diversity. The community of each size aggregate was highly organized, indicating highly specific conditions within the Microcystis phycosphere. While the communities of medium and small-size aggregates clustered together in August and September samples, large- and medium-size aggregate communities in the October sample were grouped together and distinct from small-size aggregate community. Pronounced changes in the absolute and relative percentages of the dominant genus from the two most important phyla Proteobacteria and Bacteroidetes were observed among the various size aggregates. Bacterial species on large and small-size aggregates likely have the ability to degrade high and low molecular weight compounds, respectively. Thus, there exists a spatial differentiation of bacterial taxa within the phycosphere, possibly operating in sequence and synergy to catalyze the turnover of complex organic matters.
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Affiliation(s)
- Haiyuan Cai
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Helong Jiang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- * E-mail:
| | - Lee R. Krumholz
- Department of Botany and Microbiology, University of Oklahoma, Norman, Oklahoma, United States of America
| | - Zhen Yang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
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16
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Lu X, Rao S, Shen Z, Lee PKH. Substrate induced emergence of different active bacterial and archaeal assemblages during biomethane production. BIORESOURCE TECHNOLOGY 2013; 148:517-24. [PMID: 24080290 DOI: 10.1016/j.biortech.2013.09.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Revised: 09/01/2013] [Accepted: 09/03/2013] [Indexed: 05/19/2023]
Abstract
This study analyzed the composition of a methane-generating microbial community and the corresponding active members during the transformation of three target substrates (food waste, cellulose or xylan) by barcoded 454 pyrosequencing of the bacterial and archaeal 16S rRNA genes in the DNA and RNA. The number of operational taxonomic units at 97% similarity for bacteria and archaea ranged from 162-261 and 31-166, respectively. Principal coordinates analysis and Venn diagram revealed that there were significant differences in the microbial community structure between the active members transforming each substrate and the inoculum. The active bacterial populations detected were those required for the hydrolysis of the amended substrate. The active archaeal populations were methanogens but the ratio of Methanosarcinales and Methanomicrobiales varied between the cultures. Overall, results of this study showed that a subset of the populations became active and altered in relative abundance during methane production according to the amended substrate.
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Affiliation(s)
- Xiaoying Lu
- School of Energy and Environment, City University of Hong Kong, Hong Kong
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17
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Makonde HM, Boga HI, Osiemo Z, Mwirichia R, Mackenzie LM, Göker M, Klenk HP. 16S-rRNA-based analysis of bacterial diversity in the gut of fungus-cultivating termites (Microtermes and Odontotermes species). Antonie van Leeuwenhoek 2013; 104:869-83. [PMID: 23942613 DOI: 10.1007/s10482-013-0001-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 08/08/2013] [Indexed: 01/10/2023]
Abstract
The interaction between termites and their gut symbionts has continued to attract the curiosity of researchers over time. The aim of this study was to characterize and compare the bacterial diversity and community structure in the guts of three termites (Odontotermes somaliensis, Odontotermes sp. and Microtermes sp.) using 16S rRNA gene sequencing of clone libraries. Clone libraries were screened by restriction fragment length polymorphism and representative clones from O. somaliensis (100 out of 330 clones), Odontotermes sp. (100 out of 359 clones) and Microtermes sp. (96 out 336 clones) were sequenced. Phylogenetic analysis indicated seven bacterial phyla were represented: Bacteroidetes, Spirochaetes, Firmicutes, Proteobacteria, Synergistetes, Planctomycetes and Actinobacteria. Sequences representing the phylum Bacteroidetes (>60 %) were the most abundant group in Odontotermes while those of Spirochaetes (29 %) and Firmicutes (23 %) were the abundant groups in Microtermes. The gut bacterial community structure within the two Odontotermes species investigated here was almost identical at the phylum level, but the Microtermes sp. had a unique bacterial community structure. Bacterial diversity was higher in Odontotermes than in Microtermes. The affiliation and clustering of the sequences, often with those from other termites' guts, indicate a majority of the gut bacteria are autochthonous having mutualistic relationships with their hosts. The findings underscore the presence of termite-specific bacterial lineages, the majority of which are still uncultured.
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Affiliation(s)
- Huxley M Makonde
- Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Inhoffenstraße 7b, 38124, Brunswick, Germany,
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18
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Roden EE, McBeth JM, Blöthe M, Percak-Dennett EM, Fleming EJ, Holyoke RR, Luther GW, Emerson D, Schieber J. The Microbial Ferrous Wheel in a Neutral pH Groundwater Seep. Front Microbiol 2012; 3:172. [PMID: 22783228 PMCID: PMC3390581 DOI: 10.3389/fmicb.2012.00172] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 04/18/2012] [Indexed: 12/16/2022] Open
Abstract
Evidence for microbial Fe redox cycling was documented in a circumneutral pH groundwater seep near Bloomington, Indiana. Geochemical and microbiological analyses were conducted at two sites, a semi-consolidated microbial mat and a floating puffball structure. In situ voltammetric microelectrode measurements revealed steep opposing gradients of O2 and Fe(II) at both sites, similar to other groundwater seep and sedimentary environments known to support microbial Fe redox cycling. The puffball structure showed an abrupt increase in dissolved Fe(II) just at its surface (∼5 cm depth), suggesting an internal Fe(II) source coupled to active Fe(III) reduction. Most probable number enumerations detected microaerophilic Fe(II)-oxidizing bacteria (FeOB) and dissimilatory Fe(III)-reducing bacteria (FeRB) at densities of 102 to 105 cells mL−1 in samples from both sites. In vitro Fe(III) reduction experiments revealed the potential for immediate reduction (no lag period) of native Fe(III) oxides. Conventional full-length 16S rRNA gene clone libraries were compared with high throughput barcode sequencing of the V1, V4, or V6 variable regions of 16S rRNA genes in order to evaluate the extent to which new sequencing approaches could provide enhanced insight into the composition of Fe redox cycling microbial community structure. The composition of the clone libraries suggested a lithotroph-dominated microbial community centered around taxa related to known FeOB (e.g., Gallionella, Sideroxydans, Aquabacterium). Sequences related to recognized FeRB (e.g., Rhodoferax, Aeromonas, Geobacter, Desulfovibrio) were also well-represented. Overall, sequences related to known FeOB and FeRB accounted for 88 and 59% of total clone sequences in the mat and puffball libraries, respectively. Taxa identified in the barcode libraries showed partial overlap with the clone libraries, but were not always consistent across different variable regions and sequencing platforms. However, the barcode libraries provided confirmation of key clone library results (e.g., the predominance of Betaproteobacteria) and an expanded view of lithotrophic microbial community composition.
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Affiliation(s)
- Eric E Roden
- NASA Astrobiology Institute, Department of Geoscience, University of Wisconsin Madison Madison, WI, USA
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19
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Han TH, Han JS, So MH, Seo JW, Ahn CM, Min DH, Yoo YS, Cha DK, Kim CG. The removal of 1,4-dioxane from polyester manufacturing process wastewater using an up-flow Biological Aerated Filter (UBAF) packed with tire chips. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2012; 47:117-129. [PMID: 22217090 DOI: 10.1080/10934529.2012.630291] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
1,4-Dioxane is one of the by-products from the polyester manufacturing process, which has been carelessly discharged into water bodies and is a weak human carcinogen. In this study, a laboratory-scale, up-flow biological aerated filter (UBAF), packed with tire chips, was investigated for the treatment of 1,4-dioxane. The UBAF was fed with effluent, containing an average of 31 mg/L of 1,4-dioxane, discharged from an anaerobic treatment unit at H Co. in the Gumi Industrial Complex, South Korea. In the batch, a maximum of 99.5 % 1,4-dioxane was removed from an influent containing 25.6 mg/L. In the continuous mode, the optimal empty bed contact time (EBCT) and air to liquid flow rate (A:L) were 8.5 hours and 30:1, respectively. It was also found that the removal efficiency of 1,4-dioxane increased with increasing loading rate within the range 0.04 to 0.31 kg 1,4-dioxane/m(3)·day. However, as the COD:1,4-dioxane ratio was increased within the range 3 to 46 (mg/L COD)/(mg/L 1,4-dioxane), the removal efficiency unexpectedly decreased.
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Affiliation(s)
- Thi-Hiep Han
- Department of the Environment Engineering, Inha University, Namgu, Incheon, Korea
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Thrash JC, Pollock J, Torok T, Coates JD. Description of the novel perchlorate-reducing bacteria Dechlorobacter hydrogenophilus gen. nov., sp. nov.and Propionivibrio militaris, sp. nov. Appl Microbiol Biotechnol 2010; 86:335-43. [PMID: 19921177 PMCID: PMC2822220 DOI: 10.1007/s00253-009-2336-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Revised: 10/14/2009] [Accepted: 10/26/2009] [Indexed: 11/30/2022]
Abstract
Novel dissimilatory perchlorate-reducing bacteria (DPRB) were isolated from enrichments conducted under conditions different from those of all previously described DPRB. Strain LT-1T was enriched using medium buffered at pH 6.6 with 2-(N-morpholino)ethanesulfonic acid (MES) and had only 95% 16S rRNA gene identity with its closest relative, Azonexus caeni. Strain MPT was enriched in the cathodic chamber of a perchlorate-reducing bioelectrical reactor (BER) and together with an additional strain, CR (99% 16S rRNA gene identity), had 97% 16S rRNA gene identity with Propionivibrio limicola. The use of perchlorate and other electron acceptors distinguished strains MPT and CR from P. limicola physiologically. Strain LT-1T had differences in electron donor utilization and optimum growth temperatures from A. caeni. Strains LT-1T and MPT are the first DPRB to be described in the Betaproteobacteria outside of the Dechloromonas and Azospira genera. On the basis of phylogenetic and physiological features, strain LT-1T represents a novel genus in the Rhodocyclaceae; strain MPT represents a novel species within the genus Propionivibrio. The names Dechlorobacter hydrogenophilus gen. nov., sp. nov and Propionivibrio militaris sp. nov. are proposed.
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Affiliation(s)
- J Cameron Thrash
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
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21
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Yang H, Schmitt-Wagner D, Stingl U, Brune A. Niche heterogeneity determines bacterial community structure in the termite gut (Reticulitermes santonensis). Environ Microbiol 2005; 7:916-32. [PMID: 15946289 DOI: 10.1111/j.1462-2920.2005.00760.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Differences in microenvironment and interactions of microorganisms within and across habitat boundaries should influence structure and diversity of the microbial communities within an ecosystem. We tested this hypothesis using the well characterized gut tract of the European subterranean termite Reticulitermes santonensis as a model. By cloning and sequencing analysis and molecular fingerprinting (terminal restriction fragment length polymorphism), we characterized the bacterial microbiota in the major intestinal habitats - the midgut, the wall of the hindgut paunch, the hindgut fluid and the intestinal protozoa. The bacterial community was very diverse (> 200 ribotypes) and comprised representatives of several phyla, including Firmicutes (mainly clostridia, streptococci and Mycoplasmatales-related clones), Bacteroidetes, Spirochaetes and a number of Proteobacteria, all of which were unevenly distributed among the four habitats. The largest group of clones fell into the so-called Termite group 1 (TG-1) phylum, which has no cultivated representatives. The majority of the TG-1 clones were associated with the protozoa and formed two phylogenetically distinct clusters, which consisted exclusively of clones previously retrieved from the gut of this and other Reticulitermes species. Also the other clones represented lineages of microorganisms that were exclusively recovered from the intestinal tract of termites. The termite specificity of these lineages was underscored by the finding that the closest relatives of the bacterial clones obtained from R. santonensis were usually derived also from the most closely related termites. Overall, differences in diversity between the different gut habitats and the uneven distribution of individual phylotypes support conclusively that niche heterogeneity is a strong determinant of the structure and spatial organization of the microbial community in the termite gut.
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Affiliation(s)
- Hong Yang
- Fachbereich Biologie, Mikrobielle Okologie, Universität Konstanz, 78457 Konstanz, Germany
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