1
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Spatola Rossi T, Gallia M, Erijman L, Figuerola E. Biotic and abiotic factors acting on community assembly in parallel anaerobic digestion systems from a brewery wastewater treatment plant. ENVIRONMENTAL TECHNOLOGY 2024:1-16. [PMID: 38686914 DOI: 10.1080/09593330.2024.2343797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 04/09/2024] [Indexed: 05/02/2024]
Abstract
Anaerobic digestion is a complex microbial process that mediates the transformation of organic waste into biogas. The performance and stability of anaerobic digesters relies on the structure and function of the microbial community. In this study, we asked whether the deterministic effect of wastewater composition outweighs the effect of reactor configuration on the structure and dynamics of anaerobic digester archaeal and bacterial communities. Biotic and abiotic factors acting on microbial community assembly in two parallel anaerobic digestion systems, an upflow anaerobic sludge blanket digestor (UASB) and a closed digester tank with a solid recycling system (CDSR), from a brewery WWTP were analysed utilizing 16S rDNA and mcrA amplicon sequencing and genome-centric metagenomics. This study confirmed the deterministic effect of the wastewater composition on bacterial community structure, while the archaeal community composition resulted better explained by organic loading rate (ORL) and volatile free acids (VFA). According to the functions assigned to the differentially abundant metagenome-assembled genomes (MAGs) between reactors, CDSR was enriched in genes related to methanol and methylamines methanogenesis, protein degradation, and sulphate and alcohol utilization. Conversely, the UASB reactor was enriched in genes associated with carbohydrate and lipid degradation, as well as amino acid, fatty acid, and propionate fermentation. By comparing interactions derived from the co-occurrence network with predicted metabolic interactions of the prokaryotic communities in both anaerobic digesters, we conclude that the overall community structure is mainly determined by habitat filtering.
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Affiliation(s)
| | - Mateo Gallia
- IB3- Institute of Biosciences, Biotechnology and Translational Biology- University of Buenos Aires Buenos Aires, Argentina
| | - Leonardo Erijman
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular 'Dr Héctor N. Torres' (INGEBI-CONICET), Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Eva Figuerola
- IB3- Institute of Biosciences, Biotechnology and Translational Biology- University of Buenos Aires Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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2
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Xu J, Wang L, Lv W, Song X, Nie Y, Wu XL. Metabolic profiling of petroleum-degrading microbial communities incubated under high-pressure conditions. Front Microbiol 2023; 14:1305731. [PMID: 38188585 PMCID: PMC10766756 DOI: 10.3389/fmicb.2023.1305731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 11/22/2023] [Indexed: 01/09/2024] Open
Abstract
While pressure is a significant characteristic of petroleum reservoirs, it is often overlooked in laboratory studies. To clarify the composition and metabolic properties of microbial communities under high-pressure conditions, we established methanogenic and sulfate-reducing enrichment cultures under high-pressure conditions using production water from the Jilin Oilfield in China. We utilized a metagenomics approach to analyze the microbial community after a 90-day incubation period. Under methanogenic conditions, Firmicutes, Deferribacteres, Ignavibacteriae, Thermotogae, and Nitrospirae, in association with the hydrogenotrophic methanogen Archaeoglobaceae and acetoclastic Methanosaeta, were highly represented. Genomes for Ca. Odinarchaeota and the hydrogen-dependent methylotrophic Ca. Methanosuratus were also recovered from the methanogenic culture. The sulfate-reducing community was dominated by Firmicutes, Thermotogae, Nitrospirae, Archaeoglobus, and several candidate taxa including Ca. Bipolaricaulota, Ca. Aminicenantes, and Candidate division WOR-3. These candidate taxa were key pantothenate producers for other community members. The study expands present knowledge of the metabolic roles of petroleum-degrading microbial communities under high-pressure conditions. Our results also indicate that microbial community interactions were shaped by syntrophic metabolism and the exchange of amino acids and cofactors among members. Furthermore, incubation under in situ pressure conditions has the potential to reveal the roles of microbial dark matter.
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Affiliation(s)
- Jinbo Xu
- School of Earth and Space Sciences, Peking University, Beijing, China
- State Key Laboratory of Enhanced Oil and Gas Recovery, Research Institute of Petroleum Exploration and Development, Beijing, China
| | - Lu Wang
- State Key Laboratory of Enhanced Oil and Gas Recovery, Research Institute of Petroleum Exploration and Development, Beijing, China
| | - Weifeng Lv
- State Key Laboratory of Enhanced Oil and Gas Recovery, Research Institute of Petroleum Exploration and Development, Beijing, China
| | - Xinmin Song
- State Key Laboratory of Enhanced Oil and Gas Recovery, Research Institute of Petroleum Exploration and Development, Beijing, China
| | - Yong Nie
- College of Engineering, Peking University, Beijing, China
| | - Xiao-Lei Wu
- College of Engineering, Peking University, Beijing, China
- Institute of Ecology, Peking University, Beijing, China
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3
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Abstract
The metabolism of a bacterial cell stretches beyond its boundaries, often connecting with the metabolism of other cells to form extended metabolic networks that stretch across communities, and even the globe. Among the least intuitive metabolic connections are those involving cross-feeding of canonically intracellular metabolites. How and why are these intracellular metabolites externalized? Are bacteria simply leaky? Here I consider what it means for a bacterium to be leaky, and I review mechanisms of metabolite externalization from the context of cross-feeding. Despite common claims, diffusion of most intracellular metabolites across a membrane is unlikely. Instead, passive and active transporters are likely involved, possibly purging excess metabolites as part of homeostasis. Re-acquisition of metabolites by a producer limits the opportunities for cross-feeding. However, a competitive recipient can stimulate metabolite externalization and initiate a positive-feedback loop of reciprocal cross-feeding.
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Affiliation(s)
- James B McKinlay
- Department of Biology, Indiana University, Bloomington, Indiana, USA;
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4
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Qian L, Yu X, Gu H, Liu F, Fan Y, Wang C, He Q, Tian Y, Peng Y, Shu L, Wang S, Huang Z, Yan Q, He J, Liu G, Tu Q, He Z. Vertically stratified methane, nitrogen and sulphur cycling and coupling mechanisms in mangrove sediment microbiomes. MICROBIOME 2023; 11:71. [PMID: 37020239 PMCID: PMC10074775 DOI: 10.1186/s40168-023-01501-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 02/20/2023] [Indexed: 06/19/2023]
Abstract
BACKGROUND Mangrove ecosystems are considered as hot spots of biogeochemical cycling, yet the diversity, function and coupling mechanism of microbially driven biogeochemical cycling along the sediment depth of mangrove wetlands remain elusive. Here we investigated the vertical profile of methane (CH4), nitrogen (N) and sulphur (S) cycling genes/pathways and their potential coupling mechanisms using metagenome sequencing approaches. RESULTS Our results showed that the metabolic pathways involved in CH4, N and S cycling were mainly shaped by pH and acid volatile sulphide (AVS) along a sediment depth, and AVS was a critical electron donor impacting mangrove sediment S oxidation and denitrification. Gene families involved in S oxidation and denitrification significantly (P < 0.05) decreased along the sediment depth and could be coupled by S-driven denitrifiers, such as Burkholderiaceae and Sulfurifustis in the surface sediment (0-15 cm). Interestingly, all S-driven denitrifier metagenome-assembled genomes (MAGs) appeared to be incomplete denitrifiers with nitrate/nitrite/nitric oxide reductases (Nar/Nir/Nor) but without nitrous oxide reductase (Nos), suggesting such sulphide-utilizing groups might be an important contributor to N2O production in the surface mangrove sediment. Gene families involved in methanogenesis and S reduction significantly (P < 0.05) increased along the sediment depth. Based on both network and MAG analyses, sulphate-reducing bacteria (SRB) might develop syntrophic relationships with anaerobic CH4 oxidizers (ANMEs) by direct electron transfer or zero-valent sulphur, which would pull forward the co-existence of methanogens and SRB in the middle and deep layer sediments. CONCLUSIONS In addition to offering a perspective on the vertical distribution of microbially driven CH4, N and S cycling genes/pathways, this study emphasizes the important role of S-driven denitrifiers on N2O emissions and various possible coupling mechanisms of ANMEs and SRB along the mangrove sediment depth. The exploration of potential coupling mechanisms provides novel insights into future synthetic microbial community construction and analysis. This study also has important implications for predicting ecosystem functions within the context of environmental and global change. Video Abstract.
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Affiliation(s)
- Lu Qian
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Xiaoli Yu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Hang Gu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Fei Liu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Yijun Fan
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Cheng Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Qiang He
- Department of Civil and Environmental Engineering, the University of Tennessee, Knoxville, TN 37996 USA
| | - Yun Tian
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen, 361005 China
| | - Yisheng Peng
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Longfei Shu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Shanquan Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Zhijian Huang
- School of Marine Science, Sun Yat-Sen University, Zhuhai, 519080 China
| | - Qingyun Yan
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Jianguo He
- School of Life Science, Sun Yat-Sen University, Guangzhou, 510275 China
| | - Guangli Liu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
| | - Qichao Tu
- Institute of Marine Science and Technology, Shandong University, Qingdao, 266237 China
| | - Zhili He
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou, 510006 China
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5
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Cross-Feedings, Competition, and Positive and Negative Synergies in a Four-Species Synthetic Community for Anaerobic Degradation of Cellulose to Methane. mBio 2023; 14:e0318922. [PMID: 36847519 PMCID: PMC10128006 DOI: 10.1128/mbio.03189-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
Complex interactions exist among microorganisms in a community to carry out ecological processes and adapt to changing environments. Here, we constructed a quad-culture consisting of a cellulolytic bacterium (Ruminiclostridium cellulolyticum), a hydrogenotrophic methanogen (Methanospirillum hungatei), an acetoclastic methanogen (Methanosaeta concilii), and a sulfate-reducing bacterium (Desulfovibrio vulgaris). The four microorganisms in the quad-culture cooperated via cross-feeding to produce methane using cellulose as the only carbon source and electron donor. The community metabolism of the quad-culture was compared with those of the R. cellulolyticum-containing tri-cultures, bi-cultures, and mono-culture. Methane production was higher in the quad-culture than the sum of the increases in the tri-cultures, which was attributed to a positive synergy of four species. In contrast, cellulose degradation by the quad-culture was lower than the additive effects of the tri-cultures which represented a negative synergy. The community metabolism of the quad-culture was compared between a control condition and a treatment condition with sulfate addition using metaproteomics and metabolic profiling. Sulfate addition enhanced sulfate reduction and decreased methane and CO2 productions. The cross-feeding fluxes in the quad-culture in the two conditions were modeled using a community stoichiometric model. Sulfate addition strengthened metabolic handoffs from R. cellulolyticum to M. concilii and D. vulgaris and intensified substrate competition between M. hungatei and D. vulgaris. Overall, this study uncovered emergent properties of higher-order microbial interactions using a four-species synthetic community. IMPORTANCE A synthetic community was designed using four microbial species that together performed distinct key metabolic processes in the anaerobic degradation of cellulose to methane and CO2. The microorganisms exhibited expected interactions, such as cross-feeding of acetate from a cellulolytic bacterium to an acetoclastic methanogen and competition of H2 between a sulfate reducing bacterium and a hydrogenotrophic methanogen. This validated our rational design of the interactions between microorganisms based on their metabolic roles. More interestingly, we also found positive and negative synergies as emergent properties of high-order microbial interactions among three or more microorganisms in cocultures. These microbial interactions can be quantitatively measured by adding and removing specific members. A community stoichiometric model was constructed to represent the fluxes in the community metabolic network. This study paved the way toward a more predictive understanding of the impact of environmental perturbations on microbial interactions sustaining geochemically significant processes in natural systems.
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6
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Zampieri G, Campanaro S, Angione C, Treu L. Metatranscriptomics-guided genome-scale metabolic modeling of microbial communities. CELL REPORTS METHODS 2023; 3:100383. [PMID: 36814842 PMCID: PMC9939383 DOI: 10.1016/j.crmeth.2022.100383] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 10/07/2022] [Accepted: 12/12/2022] [Indexed: 01/09/2023]
Abstract
Multi-omics data integration via mechanistic models of metabolism is a scalable and flexible framework for exploring biological hypotheses in microbial systems. However, although most microorganisms are unculturable, such multi-omics modeling is limited to isolate microbes or simple synthetic communities. Here, we developed an approach for modeling microbial activity and interactions that leverages the reconstruction of metagenome-assembled genomes and associated genome-centric metatranscriptomes. At its core, we designed a method for condition-specific metabolic modeling of microbial communities through the integration of metatranscriptomic data. Using this approach, we explored the behavior of anaerobic digestion consortia driven by hydrogen availability and human gut microbiota dysbiosis associated with Crohn's disease, identifying condition-dependent amino acid requirements in archaeal species and a reduced short-chain fatty acid exchange network associated with disease, respectively. Our approach can be applied to complex microbial communities, allowing a mechanistic contextualization of multi-omics data on a metagenome scale.
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Affiliation(s)
- Guido Zampieri
- Department of Biology, University of Padova, Padova 35121, Italy
| | - Stefano Campanaro
- Department of Biology, University of Padova, Padova 35121, Italy
- CRIBI Biotechnology Center, University of Padova, Padova 35121, Italy
| | - Claudio Angione
- School of Computing, Engineering and Digital Technologies, Teesside University, Middlesbrough TS1 3BX, UK
- National Horizons Centre, Teesside University, Darlington DL1 1HG, UK
- Centre for Digital Innovation, Teesside University, Middlesbrough TS1 3BX, UK
| | - Laura Treu
- Department of Biology, University of Padova, Padova 35121, Italy
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7
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Interspecies Formate Exchange Drives Syntrophic Growth of Syntrophotalea carbinolica and Methanococcus maripaludis. Appl Environ Microbiol 2022; 88:e0115922. [PMID: 36374033 PMCID: PMC9746305 DOI: 10.1128/aem.01159-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The complete remineralization of organic matter in anoxic environments relies on communities of microorganisms that ferment organic acids and alcohols to CH4. This is accomplished through syntrophic association of H2 or formate producing bacteria and methanogenic archaea, where exchange of these intermediates enables growth of both organisms. While these communities are essential to Earth's carbon cycle, our understanding of the dynamics of H2 or formate exchanged is limited. Here, we establish a model partnership between Syntrophotalea carbinolica and Methanococcus maripaludis. Through sequencing a transposon mutant library of M. maripaludis grown with ethanol oxidizing S. carbinolica, we found that genes encoding the F420-dependent formate dehydrogenase (Fdh) and F420-dependent methylene-tetrahydromethanopterin dehydrogenase (Mtd) are important for growth. Competitive growth of M. maripaludis mutants defective in either H2 or formate metabolism verified that, across multiple substrates, interspecies formate exchange was dominant in these communities. Agitation of these cultures to facilitate diffusive loss of H2 to the culture headspace resulted in an even greater competitive advantage for M. maripaludis strains capable of oxidizing formate. Finally, we verified that an M. maripaludis Δmtd mutant had a defect during syntrophic growth. Together, these results highlight the importance of formate exchange for the growth of methanogens under syntrophic conditions. IMPORTANCE In the environment, methane is typically generated by fermentative bacteria and methanogenic archaea working together in a process called syntrophy. Efficient exchange of small molecules like H2 or formate is essential for growth of both organisms. However, difficulties in determining the relative contribution of these intermediates to methanogenesis often hamper efforts to understand syntrophic interactions. Here, we establish a model syntrophic coculture composed of S. carbinolica and the genetically tractable methanogen M. maripaludis. Using mutant strains of M. maripaludis that are defective for either H2 or formate metabolism, we determined that interspecies formate exchange drives syntrophic growth of these organisms. Together, these results advance our understanding of the degradation of organic matter in anoxic environments.
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8
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Su X, Cui L, Tang Y, Wen T, Yang K, Wang Y, Zhang J, Zhu G, Yang X, Hou L, Zhu YG. Denitrification and N 2O Emission in Estuarine Sediments in Response to Ocean Acidification: From Process to Mechanism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:14828-14839. [PMID: 36194569 DOI: 10.1021/acs.est.2c03550] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Global estuarine ecosystems are experiencing severe nitrogen pollution and ocean acidification (OA) simultaneously. Sedimentary denitrification is an important way of reactive nitrogen removal but at the same time leads to the emission of large amounts of nitrous oxide (N2O), a potent greenhouse gas. It is known that OA in estuarine regions could impact denitrification and N2O production; however, the underlying mechanism is still underexplored. Here, sediment incubation and pure culture experiments were conducted to explore the OA impacts on microbial denitrification and the associated N2O emissions in estuarine sediments. Under neutral (in situ) conditions, fungal N2O emission dominated in the sediment, while the bacterial and fungal sources had a similar role under acidification. This indicated that acidification decreased the sedimentary fungal denitrification and likely inhibited the activity of fungal denitrifiers. To explore molecular mechanisms, a denitrifying fungal strain of Penicillium janthinellum was isolated from the sediments. By using deuterium-labeled single-cell Raman spectroscopy and isobaric tags for relative and absolute quantitation proteomics, we found that acidification inhibited electron transfers in P. janthinellum and downregulated expressions of the proteins related to energy production and conservation. Two collaborative pathways of energy generation in the P. janthinellum were further revealed, that is, aerobic oxidative phosphorylation and TCA cycle and anoxic pyruvate fermentation. This indicated a distinct energy supply strategy from bacterial denitrification. Our study provides insights into fungi-mediated nitrogen cycle in acidifying aquatic ecosystems.
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Affiliation(s)
- Xiaoxuan Su
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment; Key Laboratory of Low-Carbon Green Agriculture in Southwestern China, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing400715, China
| | - Li Cui
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
| | - Yijia Tang
- School of Life and Environmental Sciences, The University of Sydney, Biomedical Building (C81), Sydney, New South Wales2015, Australia
| | - Teng Wen
- School of Geography, Nanjing Normal University, Nanjing210023, China
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing210023, China
| | - Kai Yang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
| | - Yingmu Wang
- College of Civil Engineering, Fuzhou University, Fuzhou350116, China
| | - Jinbo Zhang
- School of Geography, Nanjing Normal University, Nanjing210023, China
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing210023, China
| | - Guibing Zhu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
| | - Xiaoru Yang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
| | - Lijun Hou
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200062, China
| | - Yong-Guan Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
- University of the Chinese Academy of Sciences, Beijing100049, China
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9
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Turkarslan S, Stopnisek N, Thompson AW, Arens CE, Valenzuela JJ, Wilson J, Hunt KA, Hardwicke J, de Lomana ALG, Lim S, Seah YM, Fu Y, Wu L, Zhou J, Hillesland KL, Stahl DA, Baliga NS. Synergistic epistasis enhances the co-operativity of mutualistic interspecies interactions. THE ISME JOURNAL 2021; 15:2233-2247. [PMID: 33612833 PMCID: PMC8319347 DOI: 10.1038/s41396-021-00919-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 12/18/2020] [Accepted: 01/29/2021] [Indexed: 01/31/2023]
Abstract
Early evolution of mutualism is characterized by big and predictable adaptive changes, including the specialization of interacting partners, such as through deleterious mutations in genes not required for metabolic cross-feeding. We sought to investigate whether these early mutations improve cooperativity by manifesting in synergistic epistasis between genomes of the mutually interacting species. Specifically, we have characterized evolutionary trajectories of syntrophic interactions of Desulfovibrio vulgaris (Dv) with Methanococcus maripaludis (Mm) by longitudinally monitoring mutations accumulated over 1000 generations of nine independently evolved communities with analysis of the genotypic structure of one community down to the single-cell level. We discovered extensive parallelism across communities despite considerable variance in their evolutionary trajectories and the perseverance within many evolution lines of a rare lineage of Dv that retained sulfate-respiration (SR+) capability, which is not required for metabolic cross-feeding. An in-depth investigation revealed that synergistic epistasis across pairings of Dv and Mm genotypes had enhanced cooperativity within SR- and SR+ assemblages, enabling their coexistence within the same community. Thus, our findings demonstrate that cooperativity of a mutualism can improve through synergistic epistasis between genomes of the interacting species, enabling the coexistence of mutualistic assemblages of generalists and their specialized variants.
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Affiliation(s)
- Serdar Turkarslan
- grid.64212.330000 0004 0463 2320Institute for Systems Biology, Seattle, WA 98109 USA
| | - Nejc Stopnisek
- grid.34477.330000000122986657Civil and Environmental Engineering, University of Washington, Seattle, WA 98195 USA
| | - Anne W. Thompson
- grid.262075.40000 0001 1087 1481Department of Biology, Portland State University, Portland, OR 97201 USA
| | - Christina E. Arens
- grid.64212.330000 0004 0463 2320Institute for Systems Biology, Seattle, WA 98109 USA
| | - Jacob J. Valenzuela
- grid.64212.330000 0004 0463 2320Institute for Systems Biology, Seattle, WA 98109 USA
| | - James Wilson
- grid.64212.330000 0004 0463 2320Institute for Systems Biology, Seattle, WA 98109 USA
| | - Kristopher A. Hunt
- grid.34477.330000000122986657Civil and Environmental Engineering, University of Washington, Seattle, WA 98195 USA
| | - Jessica Hardwicke
- grid.34477.330000000122986657Civil and Environmental Engineering, University of Washington, Seattle, WA 98195 USA
| | | | - Sujung Lim
- grid.20861.3d0000000107068890Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 USA
| | - Yee Mey Seah
- grid.462982.30000 0000 8883 2602Biological Sciences, University of Washington Bothell, Bothell, WA 98011 USA
| | - Ying Fu
- grid.266900.b0000 0004 0447 0018Institute for Environmental Genomics and Department of Microbiology & Plant Biology, University of Oklahoma, Norman, OK 73072 USA
| | - Liyou Wu
- grid.266900.b0000 0004 0447 0018Institute for Environmental Genomics and Department of Microbiology & Plant Biology, University of Oklahoma, Norman, OK 73072 USA
| | - Jizhong Zhou
- grid.266900.b0000 0004 0447 0018Institute for Environmental Genomics and Department of Microbiology & Plant Biology, University of Oklahoma, Norman, OK 73072 USA
| | - Kristina L. Hillesland
- grid.462982.30000 0000 8883 2602Biological Sciences, University of Washington Bothell, Bothell, WA 98011 USA
| | - David A. Stahl
- grid.34477.330000000122986657Civil and Environmental Engineering, University of Washington, Seattle, WA 98195 USA
| | - Nitin S. Baliga
- grid.64212.330000 0004 0463 2320Institute for Systems Biology, Seattle, WA 98109 USA
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10
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Kevorkian RT, Callahan S, Winstead R, Lloyd KG. ANME-1 archaea may drive methane accumulation and removal in estuarine sediments. ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:185-194. [PMID: 33462984 DOI: 10.1111/1758-2229.12926] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
ANME-1 archaea subsist on the very low energy of anaerobic oxidation of methane (AOM). Most marine sediments shift from net AOM in the sulfate methane transition zone (SMTZ) to methanogenesis in the methane zone (MZ) below it. In White Oak River estuarine sediments, ANME-1 comprised 99.5% of 16S rRNA genes from amplicons and 100% of 16S rRNA genes from metagenomes of the Methanomicrobia in the SMTZ and 99.9% and 98.3%, respectively, in the MZ. Each of the 16 ANME-1 OTUs (97% similarity) had peaks in the SMTZ that coincided with peaks of putative sulfate-reducing bacteria Desulfatiglans sp. and SEEP-SRB1. In the MZ, ANME-1, but none of the putative sulfate-reducing bacteria or cultured methanogens, increased with depth. Our meta-analysis of public data showed only ANME-1 expressed methanogenic genes during both net AOM and net methanogenesis in an enrichment culture. We conclude that ANME-1 perform AOM in the SMTZ and methanogenesis in the MZ of White Oak River sediments. This metabolic flexibility may expand habitable zones in extraterrestrial environments, since it enables greater energy yields in a fluctuating energetic landscape.
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Affiliation(s)
| | - Sean Callahan
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
| | - Rachel Winstead
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
| | - Karen G Lloyd
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
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Analysis of a Methanogen and an Actinobacterium Dominating the Thermophilic Microbial Community of an Electromethanogenic Biocathode. ACTA ACUST UNITED AC 2021; 2021:8865133. [PMID: 33746613 PMCID: PMC7943316 DOI: 10.1155/2021/8865133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 02/09/2021] [Accepted: 02/15/2021] [Indexed: 12/13/2022]
Abstract
Electromethanogenesis refers to the bioelectrochemical synthesis of methane from CO2 by biocathodes. In an electromethanogenic system using thermophilic microorganisms, metagenomic analysis along with quantitative real-time polymerase chain reaction and fluorescence in situ hybridization revealed that the biocathode microbiota was dominated by the methanogen Methanothermobacter sp. strain EMTCatA1 and the actinobacterium Coriobacteriaceae sp. strain EMTCatB1. RNA sequencing was used to compare the transcriptome profiles of each strain at the methane-producing biocathodes with those in an open circuit and with the methanogenesis inhibitor 2-bromoethanesulfonate (BrES). For the methanogen, genes related to hydrogenotrophic methanogenesis were highly expressed in a manner similar to those observed under H2-limited conditions. For the actinobacterium, the expression profiles of genes encoding multiheme c-type cytochromes and membrane-bound oxidoreductases suggested that the actinobacterium directly takes up electrons from the electrode. In both strains, various stress-related genes were commonly induced in the open-circuit biocathodes and biocathodes with BrES. This study provides a molecular inventory of the dominant species of an electromethanogenic biocathode with functional insights and therefore represents the first multiomics characterization of an electromethanogenic biocathode.
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12
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Fritts RK, McCully AL, McKinlay JB. Extracellular Metabolism Sets the Table for Microbial Cross-Feeding. Microbiol Mol Biol Rev 2021; 85:e00135-20. [PMID: 33441489 PMCID: PMC7849352 DOI: 10.1128/mmbr.00135-20] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The transfer of nutrients between cells, or cross-feeding, is a ubiquitous feature of microbial communities with emergent properties that influence our health and orchestrate global biogeochemical cycles. Cross-feeding inevitably involves the externalization of molecules. Some of these molecules directly serve as cross-fed nutrients, while others can facilitate cross-feeding. Altogether, externalized molecules that promote cross-feeding are diverse in structure, ranging from small molecules to macromolecules. The functions of these molecules are equally diverse, encompassing waste products, enzymes, toxins, signaling molecules, biofilm components, and nutrients of high value to most microbes, including the producer cell. As diverse as the externalized and transferred molecules are the cross-feeding relationships that can be derived from them. Many cross-feeding relationships can be summarized as cooperative but are also subject to exploitation. Even those relationships that appear to be cooperative exhibit some level of competition between partners. In this review, we summarize the major types of actively secreted, passively excreted, and directly transferred molecules that either form the basis of cross-feeding relationships or facilitate them. Drawing on examples from both natural and synthetic communities, we explore how the interplay between microbial physiology, environmental parameters, and the diverse functional attributes of extracellular molecules can influence cross-feeding dynamics. Though microbial cross-feeding interactions represent a burgeoning field of interest, we may have only begun to scratch the surface.
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Affiliation(s)
- Ryan K Fritts
- Department of Biology, Indiana University, Bloomington, Indiana, USA
| | | | - James B McKinlay
- Department of Biology, Indiana University, Bloomington, Indiana, USA
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Ranava D, Backes C, Karthikeyan G, Ouari O, Soric A, Guiral M, Cárdenas ML, Giudici-Orticoni MT. Metabolic Exchange and Energetic Coupling between Nutritionally Stressed Bacterial Species: Role of Quorum-Sensing Molecules. mBio 2021; 12:e02758-20. [PMID: 33468690 PMCID: PMC7845633 DOI: 10.1128/mbio.02758-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 11/18/2020] [Indexed: 12/29/2022] Open
Abstract
Formation of multispecies communities allows nearly every niche on earth to be colonized, and the exchange of molecular information among neighboring bacteria in such communities is key for bacterial success. To clarify the principles controlling interspecies interactions, we previously developed a coculture model with two anaerobic bacteria, Clostridium acetobutylicum (Gram positive) and Desulfovibrio vulgaris Hildenborough (Gram negative, sulfate reducing). Under conditions of nutritional stress for D. vulgaris, the existence of tight cell-cell interactions between the two bacteria induced emergent properties. Here, we show that the direct exchange of carbon metabolites produced by C. acetobutylicum allows D vulgaris to duplicate its DNA and to be energetically viable even without its substrates. We identify the molecular basis of the physical interactions and how autoinducer-2 (AI-2) molecules control the interactions and metabolite exchanges between C. acetobutylicum and D. vulgaris (or Escherichia coli and D. vulgaris). With nutrients, D. vulgaris produces a small molecule that inhibits in vitro the AI-2 activity and could act as an antagonist in vivo Sensing of AI-2 by D. vulgaris could induce formation of an intercellular structure that allows directly or indirectly metabolic exchange and energetic coupling between the two bacteria.IMPORTANCE Bacteria have usually been studied in single culture in rich media or under specific starvation conditions. However, in nature they coexist with other microorganisms and build an advanced society. The molecular bases of the interactions controlling this society are poorly understood. Use of a synthetic consortium and reducing complexity allow us to shed light on the bacterial communication at the molecular level. This study presents evidence that quorum-sensing molecule AI-2 allows physical and metabolic interactions in the synthetic consortium and provides new insights into the link between metabolism and bacterial communication.
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Affiliation(s)
- David Ranava
- CNRS, Aix-Marseille University, Bioenergetic and Protein Engineering Laboratory, Mediterranean Institute of Microbiology, Marseille, France
| | - Cassandra Backes
- CNRS, Aix-Marseille University, Bioenergetic and Protein Engineering Laboratory, Mediterranean Institute of Microbiology, Marseille, France
| | | | - Olivier Ouari
- Aix-Marseille University, CNRS, UMR 7273, ICR, Marseille, France
| | - Audrey Soric
- Aix-Marseille University, CNRS, Centrale Marseille, M2P2, Marseille, France
| | - Marianne Guiral
- CNRS, Aix-Marseille University, Bioenergetic and Protein Engineering Laboratory, Mediterranean Institute of Microbiology, Marseille, France
| | - María Luz Cárdenas
- CNRS, Aix-Marseille University, Bioenergetic and Protein Engineering Laboratory, Mediterranean Institute of Microbiology, Marseille, France
| | - Marie Thérèse Giudici-Orticoni
- CNRS, Aix-Marseille University, Bioenergetic and Protein Engineering Laboratory, Mediterranean Institute of Microbiology, Marseille, France
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Luo Y, Xiao Y, Zhao J, Zhang H, Chen W, Zhai Q. The role of mucin and oligosaccharides via cross-feeding activities by Bifidobacterium: A review. Int J Biol Macromol 2020; 167:1329-1337. [PMID: 33202267 DOI: 10.1016/j.ijbiomac.2020.11.087] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/06/2020] [Accepted: 11/12/2020] [Indexed: 02/07/2023]
Abstract
Bifidobacteria are one genus of low-abundance gut commensals that are often associated with host health-promoting effects. Bifidobacteria can degrade various dietary fibers (i.e., galactooligosaccharides, fructooligosaccharides, inulin), and are reported as one of the few gut-dwelling microbes that can utilize host-derived carbohydrates (mucin and human milk oligosaccharides). Previous studies have noted that the superior carbohydrate-metabolizing abilities of bifidobacteria facilitate the intestinal colonization of this genus and also benefit other gut symbionts, in particular butyrate-producing bacteria, via cooperative metabolic interactions. Given that such cross-feeding activities of bifidobacteria on mucin and oligosaccharides have not been systematically summarized, here we review the carbohydrate-degrading capabilities of various bifidobacterial strains that were identified in vitro experiments, the core enzymes involved in the degradation mechanisms, and social behavior between bifidobacteria and other intestinal microbes, as well as among species-specific bifidobacterial strains. The purpose of this review is to enhance our understanding of the interactions of prebiotics and probiotics, which sheds new light on the future use of oligosaccharides and bifidobacteria for nutritional intervention or clinical application.
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Affiliation(s)
- Yanhong Luo
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Yue Xiao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Jianxin Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, China; (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou 225004, China; Wuxi Translational Medicine Research Center and Jiangsu Translational Medicine Research Institute Wuxi Branch, China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, China; Beijing Innovation Centre of Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Qixiao Zhai
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Research Laboratory for Probiotics at Jiangnan University, Wuxi, Jiangsu 214122, China.
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15
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Zamanpour MK, Kaliappan RS, Rockne KJ. Gas ebullition from petroleum hydrocarbons in aquatic sediments: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 271:110997. [PMID: 32778285 DOI: 10.1016/j.jenvman.2020.110997] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 05/19/2020] [Accepted: 06/21/2020] [Indexed: 06/11/2023]
Abstract
Gas ebullition in sediment results from biogenic gas production by mixtures of bacteria and archaea. It often occurs in organic-rich sediments that have been impacted by petroleum hydrocarbon (PHC) and other anthropogenic pollution. Ebullition occurs under a relatively narrow set of biological, chemical, and sediment geomechanical conditions. This process occurs in three phases: I) biogenic production of primarily methane and dissolved phase transport of the gases in the pore water to a bubble nucleation site, II) bubble growth and sediment fracture, and III) bubble rise to the surface. The rate of biogenic gas production in phase I and the resistance of the sediment to gas fracture in phase II play the most significant roles in ebullition kinetics. What is less understood is the role that substrate structure plays in the rate of methanogenesis that drives gas ebullition. It is well established that methanogens have a very restricted set of compounds that can serve as substrates, so any complex organic molecule must first be broken down to fermentable compounds. Given that most ebullition-active sediments are completely anaerobic, the well-known difficulty in degrading PHCs under anaerobic conditions suggests potential limitations on PHC-derived gas ebullition. To date, there are no studies that conclusively demonstrate that weathered PHCs can alone drive gas ebullition. This review consists of an overview of the factors affecting gas ebullition and the biochemistry of anaerobic PHC biodegradation and methanogenesis in sediment systems. We next compile results from the scholarly literature on PHCs serving as a source of methanogenesis. We combine these results to assess the potential for PHC-driven gas ebullition using energetics, kinetics, and sediment geomechanics analyses. The results suggest that short chain <C10 alkanes are the only PHC class that alone may have the potential to drive ebullition, and that PHC-derived methanogenesis likely plays a minor part in driving gas ebullition in contaminated sediments compared to natural organic matter.
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Affiliation(s)
| | - Raja Shankar Kaliappan
- Department of Civil and Materials Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Karl John Rockne
- Department of Civil and Materials Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA.
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Tschoeke DA, Coutinho FH, Leomil L, Cavalcanti G, Silva BS, Garcia GD, Dos Anjos LC, Nascimento LB, Moreira LS, Otsuki K, Cordeiro RC, Rezende CE, Thompson FL, Thompson CC. New bacterial and archaeal lineages discovered in organic rich sediments of a large tropical Bay. Mar Genomics 2020; 54:100789. [PMID: 32563694 DOI: 10.1016/j.margen.2020.100789] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 12/15/2022]
Abstract
The nutrient and oxygen gradient present in marine sediments promotes high levels of microbial diversity. We applied metagenomics and biogeochemical tools to analyze microbial communities in different sediment depths (0-4 m below sea floor, mbsf) from Guanabara Bay, Brazil, a brackish tropical ecosystem with a history of massive anthropogenic impacts, and a largely unknown sediment microbial diversity. Methanogens (e.g. Methanosarcinales, Methanomicrobiales) were more abundant at 1 mbsf, while sulphate-reducing microbes (Desulfurococcales, Thermoprotales, and Sulfolobales) were more abundant at deeper layers (4 mbsf; corresponding to 3 K Radiocarbon years before present, Holocene Epoch). Taxonomic analyzes and functional gene identification associated with anaerobic methane oxidation (e.g. monomethylamine methyltransferase (mtmB), trimethylamine methyltransferase (mttB) and CO dehydrogenase/acetyl-CoA synthase delta subunit) and sulfate reduction indicated the dominance of Campylobacteria (Sulfurimonas) at deeper sediment layers. Gene sequences related to assimilation of inorganic sulfur increased with depth, while organic sulfur related sequences decrease, accompanying the clear reduction in the concentration of sulfur, organic carbon and chla torwards deeper layers. Analyzes of metagenome assembled genomes also led to the discovery of a novel order within the phylum Acidobacteriota, named Guanabacteria. This novel order had several in silico phenotyping features that differentiate it from closely related phylogenetic neighbors (e.g. Acidobacteria, Aminicenantes, and Thermoanaerobaculum), including several genes (carbon monoxide dehydrogenase, CO dehydrogenase/CO-methylating acetyl-CoA synthase complex subunit beta, heterodisulfide reductase, sulfite exporter TauE/SafE family protein, sulfurtransferase) that relevant for the S and C cycles. Furthermore, the recovered Bathyarchaeota genome SS9 illustrates the methanogenic potential in deeper sediment layer.
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Affiliation(s)
- Diogo A Tschoeke
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Núcleo Professor Rogerio Valle de Produção Sustentável-SAGE/COPPE, Centro de Gestão Tecnológica-CT2, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Programa de Engenharia Biomédica, COPPE, CT, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil.
| | - Felipe H Coutinho
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Evolutionary Genomics Group, Departamento de Producción Vegetal y Microbiología, Universidad Miguel Hernández, Alicante, Spain
| | - Luciana Leomil
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Núcleo Professor Rogerio Valle de Produção Sustentável-SAGE/COPPE, Centro de Gestão Tecnológica-CT2, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Giselle Cavalcanti
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Núcleo Professor Rogerio Valle de Produção Sustentável-SAGE/COPPE, Centro de Gestão Tecnológica-CT2, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Bruno S Silva
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Núcleo Professor Rogerio Valle de Produção Sustentável-SAGE/COPPE, Centro de Gestão Tecnológica-CT2, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Gizele D Garcia
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Universidade Federal do Rio de Janeiro (UFRJ), Departamento de Ensino de Graduação, Campus UFRJ - Macaé Professor Aloisio Teixeira, Macaé, RJ, Brazil
| | - Leandro Candeia Dos Anjos
- Programa de Geoquímica, Departamento de Geoquímica, Instituto de Química, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Larissa Borges Nascimento
- Programa de Geoquímica, Departamento de Geoquímica, Instituto de Química, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Luciane S Moreira
- Programa de Geoquímica, Departamento de Geoquímica, Instituto de Química, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Koko Otsuki
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Núcleo Professor Rogerio Valle de Produção Sustentável-SAGE/COPPE, Centro de Gestão Tecnológica-CT2, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Renato C Cordeiro
- Programa de Geoquímica, Departamento de Geoquímica, Instituto de Química, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Carlos E Rezende
- Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, UENF, RJ, Brazil
| | - Fabiano L Thompson
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Núcleo Professor Rogerio Valle de Produção Sustentável-SAGE/COPPE, Centro de Gestão Tecnológica-CT2, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Cristiane C Thompson
- Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Núcleo Professor Rogerio Valle de Produção Sustentável-SAGE/COPPE, Centro de Gestão Tecnológica-CT2, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil.
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17
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Liu Y, Gu M, Yin Q, Du J, Wu G. Thermodynamic analysis of direct interspecies electron transfer in syntrophic methanogenesis based on the optimized energy distribution. BIORESOURCE TECHNOLOGY 2020; 297:122345. [PMID: 31706892 DOI: 10.1016/j.biortech.2019.122345] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 10/23/2019] [Accepted: 10/25/2019] [Indexed: 06/10/2023]
Abstract
The aim of this study was to investigate the syntrophic methanogenesis from the perspective of energy transfer and competition. Effects of redox materials and redox potential on direct interspecies electron transfer (DIET) were examined through thermodynamic analysis based on the energy distribution principle. Types of redox materials could affect the efficiency of DIET via changing the total energy supply of the syntrophic methanogenesis. Decreasing system redox potential could facilitate DIET through increasing the total available energy. The competition between hydrogenotrophic methanogens and DIET methanogens might be the reason for the low proportion of the DIET pathway in the syntrophic methanogenesis. A facilitation mechanism of DIET was proposed based on the energy distribution. Providing sufficient electrons, inhibiting hydrogenotrophic methanogens and adding more competitive redox couples to avoid hydrogen generation might be beneficial for the facilitation of DIET.
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Affiliation(s)
- Yu Liu
- Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China
| | - Mengqi Gu
- Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China
| | - Qidong Yin
- Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China
| | - Jin Du
- Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China
| | - Guangxue Wu
- Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China.
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18
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Changes in the Substrate Source Reveal Novel Interactions in the Sediment-Derived Methanogenic Microbial Community. Int J Mol Sci 2019; 20:ijms20184415. [PMID: 31500341 PMCID: PMC6770359 DOI: 10.3390/ijms20184415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 09/05/2019] [Accepted: 09/06/2019] [Indexed: 12/23/2022] Open
Abstract
Methanogenesis occurs in many natural environments and is used in biotechnology for biogas production. The efficiency of methane production depends on the microbiome structure that determines interspecies electron transfer. In this research, the microbial community retrieved from mining subsidence reservoir sediment was used to establish enrichment cultures on media containing different carbon sources (tryptone, yeast extract, acetate, CO2/H2). The microbiome composition and methane production rate of the cultures were screened as a function of the substrate and transition stage. The relationships between the microorganisms involved in methane formation were the major focus of this study. Methanogenic consortia were identified by next generation sequencing (NGS) and functional genes connected with organic matter transformation were predicted using the PICRUSt approach and annotated in the KEGG. The methane production rate (exceeding 12.8 mg CH4 L−1 d−1) was highest in the culture grown with tryptone, yeast extract, and CO2/H2. The analysis of communities that developed on various carbon sources casts new light on the ecophysiology of the recently described bacterial phylum Caldiserica and methanogenic Archaea representing the genera Methanomassiliicoccus and Methanothrix. Furthermore, it is hypothesized that representatives of Caldiserica may support hydrogenotrophic methanogenesis.
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Topçuoğlu BD, Meydan C, Nguyen TB, Lang SQ, Holden JF. Growth Kinetics, Carbon Isotope Fractionation, and Gene Expression in the Hyperthermophile Methanocaldococcus jannaschii during Hydrogen-Limited Growth and Interspecies Hydrogen Transfer. Appl Environ Microbiol 2019; 85:e00180-19. [PMID: 30824444 PMCID: PMC6495749 DOI: 10.1128/aem.00180-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 02/15/2019] [Indexed: 11/20/2022] Open
Abstract
Hyperthermophilic methanogens are often H2 limited in hot subseafloor environments, and their survival may be due in part to physiological adaptations to low H2 conditions and interspecies H2 transfer. The hyperthermophilic methanogen Methanocaldococcus jannaschii was grown in monoculture at high (80 to 83 μM) and low (15 to 27 μM) aqueous H2 concentrations and in coculture with the hyperthermophilic H2 producer Thermococcus paralvinellae The purpose was to measure changes in growth and CH4 production kinetics, CH4 fractionation, and gene expression in M. jannaschii with changes in H2 flux. Growth and cell-specific CH4 production rates of M. jannaschii decreased with decreasing H2 availability and decreased further in coculture. However, cell yield (cells produced per mole of CH4 produced) increased 6-fold when M. jannaschii was grown in coculture rather than monoculture. Relative to high H2 concentrations, isotopic fractionation of CO2 to CH4 (εCO2-CH4) was 16‰ larger for cultures grown at low H2 concentrations and 45‰ and 56‰ larger for M. jannaschii growth in coculture on maltose and formate, respectively. Gene expression analyses showed H2-dependent methylene-tetrahydromethanopterin (H4MPT) dehydrogenase expression decreased and coenzyme F420-dependent methylene-H4MPT dehydrogenase expression increased with decreasing H2 availability and in coculture growth. In coculture, gene expression decreased for membrane-bound ATP synthase and hydrogenase. The results suggest that H2 availability significantly affects the CH4 and biomass production and CH4 fractionation by hyperthermophilic methanogens in their native habitats.IMPORTANCE Hyperthermophilic methanogens and H2-producing heterotrophs are collocated in high-temperature subseafloor environments, such as petroleum reservoirs, mid-ocean ridge flanks, and hydrothermal vents. Abiotic flux of H2 can be very low in these environments, and there is a gap in our knowledge about the origin of CH4 in these habitats. In the hyperthermophile Methanocaldococcus jannaschii, growth yields increased as H2 flux, growth rates, and CH4 production rates decreased. The same trend was observed increasingly with interspecies H2 transfer between M. jannaschii and the hyperthermophilic H2 producer Thermococcus paralvinellae With decreasing H2 availability, isotopic fractionation of carbon during methanogenesis increased, resulting in isotopically more negative CH4 with a concomitant decrease in H2-dependent methylene-tetrahydromethanopterin dehydrogenase gene expression and increase in F420-dependent methylene-tetrahydromethanopterin dehydrogenase gene expression. The significance of our research is in understanding the nature of hyperthermophilic interspecies H2 transfer and identifying biogeochemical and molecular markers for assessing the physiological state of methanogens and possible source of CH4 in natural environments.
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Affiliation(s)
- Begüm D Topçuoğlu
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Cem Meydan
- Institute for Computational Biomedicine, Weill Cornell Medical College, New York, New York, USA
| | - Tran B Nguyen
- School of the Earth, Ocean, and Environment, University of South Carolina, Columbia, South Carolina, USA
| | - Susan Q Lang
- School of the Earth, Ocean, and Environment, University of South Carolina, Columbia, South Carolina, USA
| | - James F Holden
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
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20
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An Escherichia coli Nitrogen Starvation Response Is Important for Mutualistic Coexistence with Rhodopseudomonas palustris. Appl Environ Microbiol 2018; 84:AEM.00404-18. [PMID: 29728387 DOI: 10.1128/aem.00404-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 04/28/2018] [Indexed: 02/04/2023] Open
Abstract
Microbial mutualistic cross-feeding interactions are ubiquitous and can drive important community functions. Engaging in cross-feeding undoubtedly affects the physiology and metabolism of individual species involved. However, the nature in which an individual species' physiology is influenced by cross-feeding and the importance of those physiological changes for the mutualism have received little attention. We previously developed a genetically tractable coculture to study bacterial mutualisms. The coculture consists of fermentative Escherichia coli and phototrophic Rhodopseudomonas palustris In this coculture, E. coli anaerobically ferments sugars into excreted organic acids as a carbon source for R. palustris In return, a genetically engineered R. palustris strain constitutively converts N2 into NH4+, providing E. coli with essential nitrogen. Using transcriptome sequencing (RNA-seq) and proteomics, we identified transcript and protein levels that differ in each partner when grown in coculture versus monoculture. When in coculture with R. palustris, E. coli gene expression changes resembled a nitrogen starvation response under the control of the transcriptional regulator NtrC. By genetically disrupting E. coli NtrC, we determined that a nitrogen starvation response is important for a stable coexistence, especially at low R. palustris NH4+ excretion levels. Destabilization of the nitrogen starvation regulatory network resulted in variable growth trends and, in some cases, extinction. Our results highlight that alternative physiological states can be important for survival within cooperative cross-feeding relationships.IMPORTANCE Mutualistic cross-feeding between microbes within multispecies communities is widespread. Studying how mutualistic interactions influence the physiology of each species involved is important for understanding how mutualisms function and persist in both natural and applied settings. Using a bacterial mutualism consisting of Rhodopseudomonas palustris and Escherichia coli growing cooperatively through bidirectional nutrient exchange, we determined that an E. coli nitrogen starvation response is important for maintaining a stable coexistence. The lack of an E. coli nitrogen starvation response ultimately destabilized the mutualism and, in some cases, led to community collapse after serial transfers. Our findings thus inform on the potential necessity of an alternative physiological state for mutualistic coexistence with another species compared to the physiology of species grown in isolation.
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Liu P, Lu Y. Concerted Metabolic Shifts Give New Insights Into the Syntrophic Mechanism Between Propionate-Fermenting Pelotomaculum thermopropionicum and Hydrogenotrophic Methanocella conradii. Front Microbiol 2018; 9:1551. [PMID: 30038609 PMCID: PMC6046458 DOI: 10.3389/fmicb.2018.01551] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 06/21/2018] [Indexed: 11/13/2022] Open
Abstract
Microbial syntrophy is a thermodynamically-based cooperation between microbial partners that share the small amounts of free energy for anaerobic growth. To gain insights into the mechanism by which syntrophic microorganisms coordinate their metabolism, we constructed cocultures of propionate-oxidizing Pelotomaculum thermopropionicum and hydrogenotrophic Methanocella conradii and compared them to monocultures. Transcriptome analysis was performed on these cultures using strand-specific mRNA sequencing (RNA-Seq). The results showed that in coculture both P. thermopropionicum and M. conradii significantly upregulated the expression of genes involved in catabolism but downregulated those for anabolic biosynthesis. Specifically, genes coding for the methylmalonyl-CoA pathway in P. thermopropionicum and key genes for methanogenesis in M. conradii were substantially upregulated in coculture compared to monoculture. The putative flavin-based electron bifurcation/confurcation systems in both organisms were also upregulated in coculture. Formate dehydrogenase encoding genes in both organisms were markedly upregulated, indicating that formate was produced and utilized by P. thermopropionicum and M. conradii, respectively. The inhibition of syntrophic activity by formate and 2-bromoethanesulphonate (2-BES) but not H2/CO2 also suggested that formate production was used by P. thermopropionicum for the recycling of intracellular redox mediators. Finally, flagellum-induced signal transduction and amino acids exchange was upregulated for syntrophic interactions. Together, our study suggests that syntrophic organisms employ multiple strategies including global metabolic shift, utilization of electron bifurcation/confurcation and employing formate as an alternate electron carrier to optimize their metabolisms for syntrophic growth.
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Affiliation(s)
- Pengfei Liu
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yahai Lu
- College of Urban and Environmental Sciences, Peking University, Beijing, China
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Fu L, Song T, Zhang W, Zhang J, Lu Y. Stimulatory Effect of Magnetite Nanoparticles on a Highly Enriched Butyrate-Oxidizing Consortium. Front Microbiol 2018; 9:1480. [PMID: 30026737 PMCID: PMC6041394 DOI: 10.3389/fmicb.2018.01480] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 06/13/2018] [Indexed: 11/13/2022] Open
Abstract
Syntrophic oxidation of butyrate is catabolized by a few bacteria specialists in the presence of methanogens. In the present study, a highly enriched butyrate-oxidizing consortium was obtained from a wetland sediment in Tibetan Plateau. During continuous transfers of the enrichment, the addition of magnetite nanoparticles (nanoFe3O4) consistently enhanced butyrate oxidation and CH4 production. Molecular analysis revealed that all bacterial sequences from the consortium belonged to Syntrophomonas with the closest relative of Syntrophomonas wolfei and 96% of the archaeal sequences were related to Methanobacteria with the remaining sequences to Methanocella. Addition of graphite and carbon nanotubes for a replacement of nanoFe3O4 caused the similar stimulatory effect. Silica coating of nanoFe3O4 surface, however, completely eliminated the stimulatory effect. The control experiment with axenic cultivation of a Syntrophomonas strain and two methanogen strains showed no effect by nanoFe3O4. Together, the results in the present study support that syntrophic oxidation of butyrate is likely facilitated by direct interspecies electron transfer in the presence of conductive nanomaterials.
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Affiliation(s)
- Li Fu
- College of Urban and Environmental Sciences, Peking University, Beijing, China
- College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Tianze Song
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Wei Zhang
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Jie Zhang
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yahai Lu
- College of Urban and Environmental Sciences, Peking University, Beijing, China
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23
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Córdova O, Chamy R, Guerrero L, Sánchez-Rodríguez A. Assessing the Effect of Pretreatments on the Structure and Functionality of Microbial Communities for the Bioconversion of Microalgae to Biogas. Front Microbiol 2018; 9:1388. [PMID: 29997601 PMCID: PMC6028723 DOI: 10.3389/fmicb.2018.01388] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 06/06/2018] [Indexed: 11/23/2022] Open
Abstract
Microalgae biomethanization is driven by anaerobic sludge associated microorganisms and is generally limited by the incomplete hydrolysis of the microalgae cell wall, which results in a low availability of microalgal biomass for the methanogenic community. The application of enzymatic pretreatments, e.g., with hydrolytic enzymes, is among the strategies used to work around the incomplete hydrolysis of the microalgae cell wall. Despite the proven efficacy of these pretreatments in increasing biomethanization, the changes that a given pretreatment may cause to the anaerobic sludge associated microorganisms during biomethanization are still unknown. This study evaluated the changes in the expression of the metatranscriptome of anaerobic sludge associated microorganisms during Chlorella sorokiniana biomethanization without pretreatment (WP) (control) and pretreated with commercial cellulase in order to increase the solubilization of the microalgal organic matter. Pretreated microalgal biomass experienced significant increases in biogas the production. The metatranscriptomic analysis of control samples showed functionally active microalgae cells, a bacterial community dominated by γ- and δ-proteobacteria, and a methanogenic community dominated by Methanospirillum hungatei. In contrast, pretreated samples were characterized by the absence of active microalgae cells and a bacteria population dominated by species of the Clostridia class. These differences are also related to the differential activation of metabolic pathways e.g., those associated with the degradation of organic matter during its biomethanization.
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Affiliation(s)
- Olivia Córdova
- Laboratorio de Biotecnología Ambiental, Escuela de Ingeniería Bioquímica, Facultad de Ingeniería, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Rolando Chamy
- Laboratorio de Biotecnología Ambiental, Escuela de Ingeniería Bioquímica, Facultad de Ingeniería, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Lorna Guerrero
- Department of Chemical and Environmental Engineering, Universidad Técnica Federico Santa, Valparaíso, Chile
| | - Aminael Sánchez-Rodríguez
- Microbial Systems Ecology and Evolution, Department of Biological Sciences, Universidad Técnica Particular de Loja, Loja, Ecuador
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D'Souza G, Shitut S, Preussger D, Yousif G, Waschina S, Kost C. Ecology and evolution of metabolic cross-feeding interactions in bacteria. Nat Prod Rep 2018; 35:455-488. [PMID: 29799048 DOI: 10.1039/c8np00009c] [Citation(s) in RCA: 240] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Literature covered: early 2000s to late 2017Bacteria frequently exchange metabolites with other micro- and macro-organisms. In these often obligate cross-feeding interactions, primary metabolites such as vitamins, amino acids, nucleotides, or growth factors are exchanged. The widespread distribution of this type of metabolic interactions, however, is at odds with evolutionary theory: why should an organism invest costly resources to benefit other individuals rather than using these metabolites to maximize its own fitness? Recent empirical work has shown that bacterial genotypes can significantly benefit from trading metabolites with other bacteria relative to cells not engaging in such interactions. Here, we will provide a comprehensive overview over the ecological factors and evolutionary mechanisms that have been identified to explain the evolution and maintenance of metabolic mutualisms among microorganisms. Furthermore, we will highlight general principles that underlie the adaptive evolution of interconnected microbial metabolic networks as well as the evolutionary consequences that result for cells living in such communities.
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Affiliation(s)
- Glen D'Souza
- Department of Environmental Systems Sciences, ETH-Zürich, Zürich, Switzerland
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25
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Wojcieszak M, Pyzik A, Poszytek K, Krawczyk PS, Sobczak A, Lipinski L, Roubinek O, Palige J, Sklodowska A, Drewniak L. Adaptation of Methanogenic Inocula to Anaerobic Digestion of Maize Silage. Front Microbiol 2017; 8:1881. [PMID: 29033919 PMCID: PMC5625012 DOI: 10.3389/fmicb.2017.01881] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 09/14/2017] [Indexed: 11/24/2022] Open
Abstract
A well-balanced microbial consortium is crucial for efficient biogas production. In turn, one of a major factor that influence on the structure of anaerobic digestion (AD) consortium is a source of microorganisms which are used as an inoculum. This study evaluated the influence of inoculum sources (with various origin) on adaptation of a biogas community and the efficiency of the biomethanization of maize silage. As initial inocula for AD of maize silage the samples from: (i) an agricultural biogas plant (ABP) which utilizes maize silage as a main substrate, (ii) cattle slurry (CS), which contain elevated levels of lignocelluloses materials, and (iii) raw sewage sludge (RSS) with low content of plant origin materials were used. The adaptation of methanogenic consortia was monitored during a series of passages, and the functionality of the adapted consortia was verified through start-up operation of AD in two-stage reactors. During the first stages of the adaptation phase, methanogenic consortia occurred very slowly, and only after several passages did the microbial community adapts to allow production of biogas with high methane content. The ABP consortium revealed highest biogas production in the adaptation and in the start-up process. The biodiversity dynamics monitored during adaptation and start-up process showed that community profile changed in a similar direction in three studied consortia. Native communities were very distinct to each other, while at the end of the Phase II of the start-up process microbial diversity profile was similar in all consortia. All adopted bacterial communities were dominated by representatives of Porphyromonadaceae, Rikenellaceae, Ruminococcaceae, and Synergistaceae. A shift from low acetate-preferring acetoclastic Methanosaetaceae (ABP and RSS) and/or hydrogenotrophic Archaea, e.g., Methanomicrobiaceae (CS) prevailing in the inoculum samples to larger populations of high acetate-preferring acetoclastic Methanosarcinaceae was observed by the end of the experiment. As a result, three independent, functional communities that syntrophically produced methane from acetate (primarily) and H2/CO2, methanol and methylamines were adapted. This study provides new insights into the specific process by which different inocula sampled from typical methanogenic environments that are commonly used to initiate industrial installations gradually adapted to allow biogas production from maize silage.
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Affiliation(s)
- Martyna Wojcieszak
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Adam Pyzik
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Krzysztof Poszytek
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Pawel S Krawczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Adam Sobczak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Leszek Lipinski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Otton Roubinek
- Institute of Nuclear Chemistry and Technology, Warsaw, Poland
| | - Jacek Palige
- Institute of Nuclear Chemistry and Technology, Warsaw, Poland
| | - Aleksandra Sklodowska
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Lukasz Drewniak
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
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26
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Hunt KA, Jennings RD, Inskeep WP, Carlson RP. Stoichiometric modelling of assimilatory and dissimilatory biomass utilisation in a microbial community. Environ Microbiol 2016; 18:4946-4960. [PMID: 27387069 PMCID: PMC5629010 DOI: 10.1111/1462-2920.13444] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Accepted: 06/30/2016] [Indexed: 11/26/2022]
Abstract
Assimilatory and dissimilatory utilisation of autotroph biomass by heterotrophs is a fundamental mechanism for the transfer of nutrients and energy across trophic levels. Metagenome data from a tractable, thermoacidophilic microbial community in Yellowstone National Park was used to build an in silico model to study heterotrophic utilisation of autotroph biomass using elementary flux mode analysis and flux balance analysis. Assimilatory and dissimilatory biomass utilisation was investigated using 29 forms of biomass-derived dissolved organic carbon (DOC) including individual monomer pools, individual macromolecular pools and aggregate biomass. The simulations identified ecologically competitive strategies for utilizing DOC under conditions of varying electron donor, electron acceptor or enzyme limitation. The simulated growth environment affected which form of DOC was the most competitive use of nutrients; for instance, oxygen limitation favoured utilisation of less reduced and fermentable DOC while carbon-limited environments favoured more reduced DOC. Additionally, metabolism was studied considering two encompassing metabolic strategies: simultaneous versus sequential use of DOC. Results of this study bound the transfer of nutrients and energy through microbial food webs, providing a quantitative foundation relevant to most microbial ecosystems.
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Affiliation(s)
- Kristopher A. Hunt
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
- Thermal Biology Institute, Montana State University, Bozeman, MT, USA
| | - Ryan deM. Jennings
- Thermal Biology Institute, Montana State University, Bozeman, MT, USA
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, USA
| | - William P. Inskeep
- Thermal Biology Institute, Montana State University, Bozeman, MT, USA
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, USA
| | - Ross P. Carlson
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
- Thermal Biology Institute, Montana State University, Bozeman, MT, USA
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27
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Großkopf T, Zenobi S, Alston M, Folkes L, Swarbreck D, Soyer OS. A stable genetic polymorphism underpinning microbial syntrophy. THE ISME JOURNAL 2016; 10:2844-2853. [PMID: 27258948 PMCID: PMC5042321 DOI: 10.1038/ismej.2016.80] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Revised: 03/28/2016] [Accepted: 04/01/2016] [Indexed: 12/22/2022]
Abstract
Syntrophies are metabolic cooperations, whereby two organisms co-metabolize a substrate in an interdependent manner. Many of the observed natural syntrophic interactions are mandatory in the absence of strong electron acceptors, such that one species in the syntrophy has to assume the role of electron sink for the other. While this presents an ecological setting for syntrophy to be beneficial, the potential genetic drivers of syntrophy remain unknown to date. Here, we show that the syntrophic sulfate-reducing species Desulfovibrio vulgaris displays a stable genetic polymorphism, where only a specific genotype is able to engage in syntrophy with the hydrogenotrophic methanogen Methanococcus maripaludis. This 'syntrophic' genotype is characterized by two genetic alterations, one of which is an in-frame deletion in the gene encoding for the ion-translocating subunit cooK of the membrane-bound COO hydrogenase. We show that this genotype presents a specific physiology, in which reshaping of energy conservation in the lactate oxidation pathway enables it to produce sufficient intermediate hydrogen for sustained M. maripaludis growth and thus, syntrophy. To our knowledge, these findings provide for the first time a genetic basis for syntrophy in nature and bring us closer to the rational engineering of syntrophy in synthetic microbial communities.
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Affiliation(s)
- Tobias Großkopf
- School of Life Sciences, The University of Warwick, Coventry, UK
| | - Simone Zenobi
- School of Life Sciences, The University of Warwick, Coventry, UK
| | - Mark Alston
- The Genome Analysis Centre, Norwich Research Park, Norwich, UK
| | - Leighton Folkes
- The Genome Analysis Centre, Norwich Research Park, Norwich, UK
| | - David Swarbreck
- The Genome Analysis Centre, Norwich Research Park, Norwich, UK
| | - Orkun S Soyer
- School of Life Sciences, The University of Warwick, Coventry, UK
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28
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Browne P, Tamaki H, Kyrpides N, Woyke T, Goodwin L, Imachi H, Bräuer S, Yavitt JB, Liu WT, Zinder S, Cadillo-Quiroz H. Genomic composition and dynamics among Methanomicrobiales predict adaptation to contrasting environments. ISME JOURNAL 2016; 11:87-99. [PMID: 27552639 DOI: 10.1038/ismej.2016.104] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 06/13/2016] [Accepted: 06/22/2016] [Indexed: 11/09/2022]
Abstract
Members of the order Methanomicrobiales are abundant, and sometimes dominant, hydrogenotrophic (H2-CO2 utilizing) methanoarchaea in a broad range of anoxic habitats. Despite their key roles in greenhouse gas emissions and waste conversion to methane, little is known about the physiological and genomic bases for their widespread distribution and abundance. In this study, we compared the genomes of nine diverse Methanomicrobiales strains, examined their pangenomes, reconstructed gene flow and identified genes putatively mediating their success across different habitats. Most strains slowly increased gene content whereas one, Methanocorpusculum labreanum, evidenced genome downsizing. Peat-dwelling Methanomicrobiales showed adaptations centered on improved transport of scarce inorganic nutrients and likely use H+ rather than Na+ transmembrane chemiosmotic gradients during energy conservation. In contrast, other Methanomicrobiales show the potential to concurrently use Na+ and H+ chemiosmotic gradients. Analyses also revealed that the Methanomicrobiales lack a canonical electron bifurcation system (MvhABGD) known to produce low potential electrons in other orders of hydrogenotrophic methanogens. Additional putative differences in anabolic metabolism suggest that the dynamics of interspecies electron transfer from Methanomicrobiales syntrophic partners can also differ considerably. Altogether, these findings suggest profound differences in electron trafficking in the Methanomicrobiales compared with other hydrogenotrophs, and warrant further functional evaluations.
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Affiliation(s)
- Patrick Browne
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Hideyuki Tamaki
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan
| | - Nikos Kyrpides
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
| | - Tanja Woyke
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
| | | | - Hiroyuki Imachi
- Department of Subsurface Geobiological Analysis and Research, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Kanagawa, Japan
| | - Suzanna Bräuer
- Department of Biology, Appalachian State University, Boone, NC, USA
| | - Joseph B Yavitt
- Department of Natural Resources, Cornell University, Ithaca, NY, USA
| | - Wen-Tso Liu
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Stephen Zinder
- Department of Microbiology, Cornell University, Ithaca, NY, USA
| | - Hinsby Cadillo-Quiroz
- School of Life Sciences, Arizona State University, Tempe, AZ, USA.,Swette Center for Environmental Biotechnology at the Biodesign Institute, Arizona State University, Tempe, AZ, USA
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Networks of energetic and metabolic interactions define dynamics in microbial communities. Proc Natl Acad Sci U S A 2015; 112:15450-5. [PMID: 26621749 DOI: 10.1073/pnas.1506034112] [Citation(s) in RCA: 145] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Microorganisms form diverse communities that have a profound impact on the environment and human health. Recent technological advances have enabled elucidation of community diversity at high resolution. Investigation of microbial communities has revealed that they often contain multiple members with complementing and seemingly redundant metabolic capabilities. An understanding of the communal impacts of redundant metabolic capabilities is currently lacking; specifically, it is not known whether metabolic redundancy will foster competition or motivate cooperation. By investigating methanogenic populations, we identified the multidimensional interspecies interactions that define composition and dynamics within syntrophic communities that play a key role in the global carbon cycle. Species-specific genomes were extracted from metagenomic data using differential coverage binning. We used metabolic modeling leveraging metatranscriptomic information to reveal and quantify a complex intertwined system of syntrophic relationships. Our results show that amino acid auxotrophies create additional interdependencies that define community composition and control carbon and energy flux through the system while simultaneously contributing to overall community robustness. Strategic use of antimicrobials further reinforces this intricate interspecies network. Collectively, our study reveals the multidimensional interactions in syntrophic communities that promote high species richness and bolster community stability during environmental perturbations.
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30
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Tan B, Jane Fowler S, Laban NA, Dong X, Sensen CW, Foght J, Gieg LM. Comparative analysis of metagenomes from three methanogenic hydrocarbon-degrading enrichment cultures with 41 environmental samples. THE ISME JOURNAL 2015; 9:2028-45. [PMID: 25734684 PMCID: PMC4542035 DOI: 10.1038/ismej.2015.22] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 01/07/2015] [Accepted: 01/09/2015] [Indexed: 11/09/2022]
Abstract
Methanogenic hydrocarbon metabolism is a key process in subsurface oil reservoirs and hydrocarbon-contaminated environments and thus warrants greater understanding to improve current technologies for fossil fuel extraction and bioremediation. In this study, three hydrocarbon-degrading methanogenic cultures established from two geographically distinct environments and incubated with different hydrocarbon substrates (added as single hydrocarbons or as mixtures) were subjected to metagenomic and 16S rRNA gene pyrosequencing to test whether these differences affect the genetic potential and composition of the communities. Enrichment of different putative hydrocarbon-degrading bacteria in each culture appeared to be substrate dependent, though all cultures contained both acetate- and H2-utilizing methanogens. Despite differing hydrocarbon substrates and inoculum sources, all three cultures harbored genes for hydrocarbon activation by fumarate addition (bssA, assA, nmsA) and carboxylation (abcA, ancA), along with those for associated downstream pathways (bbs, bcr, bam), though the cultures incubated with hydrocarbon mixtures contained a broader diversity of fumarate addition genes. A comparative metagenomic analysis of the three cultures showed that they were functionally redundant despite their enrichment backgrounds, sharing multiple features associated with syntrophic hydrocarbon conversion to methane. In addition, a comparative analysis of the culture metagenomes with those of 41 environmental samples (containing varying proportions of methanogens) showed that the three cultures were functionally most similar to each other but distinct from other environments, including hydrocarbon-impacted environments (for example, oil sands tailings ponds and oil-affected marine sediments). This study provides a basis for understanding key functions and environmental selection in methanogenic hydrocarbon-associated communities.
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Affiliation(s)
- Boonfei Tan
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - S Jane Fowler
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Nidal Abu Laban
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Xiaoli Dong
- Visual Genomics Centre, Faculty of Medicine, Calgary, Alberta, Canada
| | | | - Julia Foght
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Lisa M Gieg
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
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31
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Thompson AW, Crow MJ, Wadey B, Arens C, Turkarslan S, Stolyar S, Elliott N, Petersen TW, van den Engh G, Stahl DA, Baliga NS. A method to analyze, sort, and retain viability of obligate anaerobic microorganisms from complex microbial communities. J Microbiol Methods 2015; 117:74-7. [PMID: 26187776 DOI: 10.1016/j.mimet.2015.07.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 07/08/2015] [Accepted: 07/09/2015] [Indexed: 10/23/2022]
Abstract
A high speed flow cytometric cell sorter was modified to maintain a controlled anaerobic environment. This technology enabled coupling of the precise high-throughput analytical and cell separation capabilities of flow cytometry to the assessment of cell viability of evolved lineages of obligate anaerobic organisms from cocultures.
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Affiliation(s)
| | | | - Brian Wadey
- BD Biosciences, Advanced Cytometry Group, Seattle, USA
| | | | | | | | - Nicholas Elliott
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | | | | | - David A Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - Nitin S Baliga
- Institute for Systems Biology, Seattle, WA, USA; Departments of Biology and Microbiology, University of Washington, Seattle, WA, USA; Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA; Lawrence Berkeley National Lab, Berkeley, CA, USA
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32
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Response of a rice paddy soil methanogen to syntrophic growth as revealed by transcriptional analyses. Appl Environ Microbiol 2015; 80:4668-76. [PMID: 24837392 DOI: 10.1128/aem.01259-14] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Members of Methanocellales are widespread in paddy field soils and play the key role in methane production. These methanogens feature largely in these organisms’ adaptation to low H2 and syntrophic growth with anaerobic fatty acid oxidizers. The adaptive mechanisms, however, remain unknown. In the present study, we determined the transcripts of 21 genes involved in the key steps of methanogenesis and acetate assimilation of Methanocella conradii HZ254, a strain recently isolated from paddy field soil. M. conradii was grown in monoculture and syntrophically with Pelotomaculum thermopropionicum (a propionate syntroph) or Syntrophothermus lipocalidus (a butyrate syntroph). Comparison of the relative transcript abundances showed that three hydrogenase-encoding genes and all methanogenesis-related genes tested were upregulated in cocultures relative to monoculture. The genes encoding formylmethanofuran dehydrogenase (Fwd), heterodisulfide reductase (Hdr), and the membrane-bound energy-converting hydrogenase (Ech) were the most upregulated among the evaluated genes. The expression of the formate dehydrogenase (Fdh)-encoding gene also was significantly upregulated. In contrast, an acetate assimilation gene was downregulated in cocultures. The genes coding for Fwd, Hdr, and the D subunit of F420-nonreducing hydrogenase (Mvh) form a large predicted transcription unit; therefore, the Mvh/Hdr/Fwd complex, capable of mediating the electron bifurcation and connecting the first and last steps of methanogenesis, was predicted to be formed in M. conradii. We propose that Methanocella methanogens cope with low H2 and syntrophic growth by (i) stabilizing the Mvh/Hdr/Fwd complex and (ii) activating formatedependent methanogenesis.
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A Post-Genomic View of the Ecophysiology, Catabolism and Biotechnological Relevance of Sulphate-Reducing Prokaryotes. Adv Microb Physiol 2015. [PMID: 26210106 DOI: 10.1016/bs.ampbs.2015.05.002] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Dissimilatory sulphate reduction is the unifying and defining trait of sulphate-reducing prokaryotes (SRP). In their predominant habitats, sulphate-rich marine sediments, SRP have long been recognized to be major players in the carbon and sulphur cycles. Other, more recently appreciated, ecophysiological roles include activity in the deep biosphere, symbiotic relations, syntrophic associations, human microbiome/health and long-distance electron transfer. SRP include a high diversity of organisms, with large nutritional versatility and broad metabolic capacities, including anaerobic degradation of aromatic compounds and hydrocarbons. Elucidation of novel catabolic capacities as well as progress in the understanding of metabolic and regulatory networks, energy metabolism, evolutionary processes and adaptation to changing environmental conditions has greatly benefited from genomics, functional OMICS approaches and advances in genetic accessibility and biochemical studies. Important biotechnological roles of SRP range from (i) wastewater and off gas treatment, (ii) bioremediation of metals and hydrocarbons and (iii) bioelectrochemistry, to undesired impacts such as (iv) souring in oil reservoirs and other environments, and (v) corrosion of iron and concrete. Here we review recent advances in our understanding of SRPs focusing mainly on works published after 2000. The wealth of publications in this period, covering many diverse areas, is a testimony to the large environmental, biogeochemical and technological relevance of these organisms and how much the field has progressed in these years, although many important questions and applications remain to be explored.
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Fujishiro T, Ataka K, Ermler U, Shima S. Towards a functional identification of catalytically inactive [Fe]-hydrogenase paralogs. FEBS J 2015; 282:3412-23. [PMID: 26094576 DOI: 10.1111/febs.13351] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 06/15/2015] [Accepted: 06/17/2015] [Indexed: 11/29/2022]
Abstract
UNLABELLED [Fe]-hydrogenase (Hmd), an enzyme of the methanogenic energy metabolism, harbors an iron-guanylylpyridinol (FeGP) cofactor used for H2 cleavage. The generated hydride is transferred to methenyl-tetrahydromethanopterin (methenyl-H4MPT(+)). Most hydrogenotrophic methanogens contain the hmd-related genes hmdII and hmdIII. Their function is still elusive. We were able to reconstitute the HmdII holoenzyme of Methanocaldococcus jannaschii with recombinantly produced apoenzyme and the FeGP cofactor, which is a prerequisite for in vitro functional analysis. Infrared spectroscopic and X-ray structural data clearly indicated binding of the FeGP cofactor. Methylene-H4MPT binding was detectable in the significantly altered infrared spectra of the HmdII holoenzyme and in the HmdII apoenzyme-methylene-H4 MPT complex structure. The related binding mode of the FeGP cofactor and methenyl-H4MPT(+) compared with Hmd and their multiple contacts to the polypeptide highly suggest a biological role in HmdII. However, holo-HmdII did not catalyze the Hmd reaction, not even in a single turnover process, as demonstrated by kinetic measurements. The found inactivity can be rationalized by an increased contact area between the C- and N-terminal folding units in HmdII compared with in Hmd, which impairs the catalytically necessary open-to-close transition, and by an exchange of a crucial histidine to a tyrosine. Mainly based on the presented data, a function of HmdII as Hmd isoenzyme, H2 sensor, FeGP-cofactor storage protein and scaffold protein for FeGP-cofactor biosynthesis could be excluded. Inspired by the recently found binding of HmdII to aminoacyl-tRNA synthetases and tRNA, we tentatively consider HmdII as a regulatory protein for protein synthesis that senses the intracellular methylene-H4 MPT concentration. DATABASE Structural data are available in the Protein Data Bank under the accession numbers 4YT8; 4YT2; 4YT4 and 4YT5.
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Affiliation(s)
- Takashi Fujishiro
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany
| | - Kenichi Ataka
- Department of Physics, Freie Universität Berlin, Germany
| | - Ulrich Ermler
- Max-Planck-Institut für Biophysik, Frankfurt/Main, Germany
| | - Seigo Shima
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany.,PRESTO, Japan Science and Technology Agency (JST), Saitama, Japan
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Tan B, Semple K, Foght J. Anaerobic alkane biodegradation by cultures enriched from oil sands tailings ponds involves multiple species capable of fumarate addition. FEMS Microbiol Ecol 2015; 91:fiv042. [PMID: 25873461 DOI: 10.1093/femsec/fiv042] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/01/2015] [Indexed: 01/18/2023] Open
Abstract
A methanogenic short-chain alkane-degrading culture (SCADC) was enriched from oil sands tailings and transferred several times with a mixture of C6, C7, C8 and C10 n-alkanes as the predominant organic carbon source, plus 2-methylpentane, 3-methylpentane and methylcyclopentane as minor components. Cultures produced ∼40% of the maximum theoretical methane during 18 months incubation while depleting the n-alkanes, 2-methylpentane and methylcyclopentane. Substrate depletion correlated with detection of metabolites characteristic of fumarate activation of 2-methylpentane and methylcyclopentane, but not n-alkane metabolites. During active methanogenesis with the mixed alkanes, reverse-transcription PCR confirmed the expression of functional genes (assA and bssA) associated with hydrocarbon addition to fumarate. Pyrosequencing of 16S rRNA genes amplified during active alkane degradation revealed enrichment of Clostridia (particularly Peptococcaceae) and methanogenic Archaea (Methanosaetaceae and Methanomicrobiaceae). Methanogenic cultures transferred into medium containing sulphate produced sulphide, depleted n-alkanes and produced the corresponding succinylated alkane metabolites, but were slow to degrade 2-methylpentane and methylcyclopentane; these cultures were enriched in Deltaproteobacteria rather than Clostridia. 3-Methylpentane was not degraded by any cultures. Thus, nominally methanogenic oil sands tailings harbour dynamic and versatile hydrocarbon-degrading fermentative syntrophs and sulphate reducers capable of degrading n-, iso- and cyclo-alkanes by addition to fumarate.
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Affiliation(s)
- BoonFei Tan
- Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Kathleen Semple
- Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Julia Foght
- Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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Mao X, Stenuit B, Polasko A, Alvarez-Cohen L. Efficient metabolic exchange and electron transfer within a syntrophic trichloroethene-degrading coculture of Dehalococcoides mccartyi 195 and Syntrophomonas wolfei. Appl Environ Microbiol 2015; 81:2015-24. [PMID: 25576615 PMCID: PMC4345365 DOI: 10.1128/aem.03464-14] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 01/02/2015] [Indexed: 01/07/2023] Open
Abstract
Dehalococcoides mccartyi 195 (strain 195) and Syntrophomonas wolfei were grown in a sustainable syntrophic coculture using butyrate as an electron donor and carbon source and trichloroethene (TCE) as an electron acceptor. The maximum dechlorination rate (9.9 ± 0.1 μmol day(-1)) and cell yield [(1.1 ± 0.3) × 10(8) cells μmol(-1) Cl(-)] of strain 195 maintained in coculture were, respectively, 2.6 and 1.6 times higher than those measured in the pure culture. The strain 195 cell concentration was about 16 times higher than that of S. wolfei in the coculture. Aqueous H2 concentrations ranged from 24 to 180 nM during dechlorination and increased to 350 ± 20 nM when TCE was depleted, resulting in cessation of butyrate fermentation by S. wolfei with a theoretical Gibbs free energy of -13.7 ± 0.2 kJ mol(-1). Carbon monoxide in the coculture was around 0.06 μmol per bottle, which was lower than that observed for strain 195 in isolation. The minimum H2 threshold value for TCE dechlorination by strain 195 in the coculture was 0.6 ± 0.1 nM. Cell aggregates during syntrophic growth were observed by scanning electron microscopy. The interspecies distances to achieve H2 fluxes required to support the measured dechlorination rates were predicted using Fick's law and demonstrated the need for aggregation. Filamentous appendages and extracellular polymeric substance (EPS)-like structures were present in the intercellular spaces. The transcriptome of strain 195 during exponential growth in the coculture indicated increased ATP-binding cassette transporter activities compared to the pure culture, while the membrane-bound energy metabolism related genes were expressed at stable levels.
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Affiliation(s)
- Xinwei Mao
- Department of Civil and Environmental Engineering, College of Engineering, University of California, Berkeley, Berkeley, California, USA
| | - Benoit Stenuit
- Department of Civil and Environmental Engineering, College of Engineering, University of California, Berkeley, Berkeley, California, USA
| | - Alexandra Polasko
- Department of Civil and Environmental Engineering, College of Engineering, University of California, Berkeley, Berkeley, California, USA
| | - Lisa Alvarez-Cohen
- Department of Civil and Environmental Engineering, College of Engineering, University of California, Berkeley, Berkeley, California, USA Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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Lim S, Stolyar S, Hillesland K. Culturing anaerobes to use as a model system for studying the evolution of syntrophic mutualism. Methods Mol Biol 2015; 1151:103-15. [PMID: 24838882 DOI: 10.1007/978-1-4939-0554-6_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Our current understanding of the evolution of mutualisms is limited partly because there have been relatively few model systems for studying it in real time. A model mutualistic interaction between the bacterium D. vulgaris and the archaeaon M. maripaludis was developed to allow for rigorous tests of general hypotheses about the evolution and ecology of mutualisms. This model system also allows us to develop an evolutionary genetics perspective on an interaction that plays a key ecological role in many oxygen-free microbial communities. Here, we describe the techniques used to make anoxic media for propagating these species alone or in conditions that require their cooperation.
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Affiliation(s)
- Sujung Lim
- Biological Sciences Division, School of STEM, UW Bothell, 358538, Bothell, WA, 98011, USA
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Brileya KA, Camilleri LB, Zane GM, Wall JD, Fields MW. Biofilm growth mode promotes maximum carrying capacity and community stability during product inhibition syntrophy. Front Microbiol 2014; 5:693. [PMID: 25566209 PMCID: PMC4266047 DOI: 10.3389/fmicb.2014.00693] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 11/22/2014] [Indexed: 12/03/2022] Open
Abstract
Sulfate-reducing bacteria (SRB) can interact syntrophically with other community members in the absence of sulfate, and interactions with hydrogen-consuming methanogens are beneficial when these archaea consume potentially inhibitory H2 produced by the SRB. A dual continuous culture approach was used to characterize population structure within a syntrophic biofilm formed by the SRB Desulfovibrio vulgaris Hildenborough and the methanogenic archaeum Methanococcus maripaludis. Under the tested conditions, monocultures of D. vulgaris formed thin, stable biofilms, but monoculture M. maripaludis did not. Microscopy of intact syntrophic biofilm confirmed that D. vulgaris formed a scaffold for the biofilm, while intermediate and steady-state images revealed that M. maripaludis joined the biofilm later, likely in response to H2 produced by the SRB. Close interactions in structured biofilm allowed efficient transfer of H2 to M. maripaludis, and H2 was only detected in cocultures with a mutant SRB that was deficient in biofilm formation (ΔpilA). M. maripaludis produced more carbohydrate (uronic acid, hexose, and pentose) as a monoculture compared to total coculture biofilm, and this suggested an altered carbon flux during syntrophy. The syntrophic biofilm was structured into ridges (∼300 × 50 μm) and models predicted lactate limitation at ∼50 μm biofilm depth. The biofilm had structure that likely facilitated mass transfer of H2 and lactate, yet maximized biomass with a more even population composition (number of each organism) when compared to the bulk-phase community. Total biomass protein was equivalent in lactate-limited and lactate-excess conditions when a biofilm was present, but in the absence of biofilm, total biomass protein was significantly reduced. The results suggest that multispecies biofilms create an environment conducive to resource sharing, resulting in increased biomass retention, or carrying capacity, for cooperative populations.
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Affiliation(s)
- Kristen A Brileya
- Department of Microbiology and Immunology, Montana State University Bozeman, MT, USA ; Center for Biofilm Engineering, Montana State University Bozeman, MT, USA
| | - Laura B Camilleri
- Department of Microbiology and Immunology, Montana State University Bozeman, MT, USA ; Center for Biofilm Engineering, Montana State University Bozeman, MT, USA
| | - Grant M Zane
- Division of Biochemistry, University of Missouri Columbia, MO, USA
| | - Judy D Wall
- Division of Biochemistry, University of Missouri Columbia, MO, USA
| | - Matthew W Fields
- Department of Microbiology and Immunology, Montana State University Bozeman, MT, USA ; Center for Biofilm Engineering, Montana State University Bozeman, MT, USA ; Thermal Biology Institute, Montana State University Bozeman, MT, USA ; Ecosystems and Networks Integrated with Genes and Molecular Assemblies Berkeley, CA, USA ; National Center for Genome Resources Santa Fe, NM, USA
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39
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Baito K, Imai S, Matsushita M, Otani M, Sato Y, Kimura H. Biogas production using anaerobic groundwater containing a subterranean microbial community associated with the accretionary prism. Microb Biotechnol 2014; 8:837-45. [PMID: 25267392 PMCID: PMC4554471 DOI: 10.1111/1751-7915.12179] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Revised: 08/12/2014] [Accepted: 08/24/2014] [Indexed: 11/05/2022] Open
Abstract
In a deep aquifer associated with an accretionary prism, significant methane (CH4) is produced by a subterranean microbial community. Here, we developed bioreactors for producing CH4 and hydrogen (H2) using anaerobic groundwater collected from the deep aquifer. To generate CH4, the anaerobic groundwater amended with organic substrates was incubated in the bioreactor. At first, H2 was detected and accumulated in the gas phase of the bioreactor. After the H2 decreased, rapid CH4 production was observed. Phylogenetic analysis targeting 16S rRNA genes revealed that the H2-producing fermentative bacterium and hydrogenotrophic methanogen were predominant in the reactor. The results suggested that syntrophic biodegradation of organic substrates by the H2-producing fermentative bacterium and the hydrogenotrophic methanogen contributed to the CH4 production. For H2 production, the anaerobic groundwater, amended with organic substrates and an inhibitor of methanogens (2-bromoethanesulfonate), was incubated in a bioreactor. After incubation for 24 h, H2 was detected from the gas phase of the bioreactor and accumulated. Bacterial 16S rRNA gene analysis suggested the dominance of the H2-producing fermentative bacterium in the reactor. Our study demonstrated a simple and rapid CH4 and H2 production utilizing anaerobic groundwater containing an active subterranean microbial community.
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Affiliation(s)
- Kyohei Baito
- Department of Geosciences, Graduate School of Science, Shizuoka University, Shizuoka, Japan
| | - Satomi Imai
- Department of Geosciences, Graduate School of Science, Shizuoka University, Shizuoka, Japan
| | - Makoto Matsushita
- Department of Geosciences, Graduate School of Science, Shizuoka University, Shizuoka, Japan
| | - Miku Otani
- Department of Geosciences, Graduate School of Science, Shizuoka University, Shizuoka, Japan
| | - Yu Sato
- Department of Geosciences, Graduate School of Science, Shizuoka University, Shizuoka, Japan
| | - Hiroyuki Kimura
- Department of Geosciences, Graduate School of Science, Shizuoka University, Shizuoka, Japan.,Center for Integrated Research and Education of Natural Hazards, Shizuoka University, Shizuoka, Japan.,PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan
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40
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Nagarajan H, Embree M, Rotaru AE, Shrestha PM, Feist AM, Palsson BØ, Lovley DR, Zengler K. Characterization and modelling of interspecies electron transfer mechanisms and microbial community dynamics of a syntrophic association. Nat Commun 2014; 4:2809. [PMID: 24264237 DOI: 10.1038/ncomms3809] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 10/23/2013] [Indexed: 12/18/2022] Open
Abstract
Syntrophic associations are central to microbial communities and thus have a fundamental role in the global carbon cycle. Despite biochemical approaches describing the physiological activity of these communities, there has been a lack of a mechanistic understanding of the relationship between complex nutritional and energetic dependencies and their functioning. Here we apply a multi-omic modelling workflow that combines genomic, transcriptomic and physiological data with genome-scale models to investigate dynamics and electron flow mechanisms in the syntrophic association of Geobacter metallireducens and Geobacter sulfurreducens. Genome-scale modelling of direct interspecies electron transfer reveals insights into the energetics of electron transfer mechanisms. While G. sulfurreducens adapts to rapid syntrophic growth by changes at the genomic and transcriptomic level, G. metallireducens responds only at the transcriptomic level. This multi-omic approach enhances our understanding of adaptive responses and factors that shape the evolution of syntrophic communities.
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Affiliation(s)
- Harish Nagarajan
- Department of Bioengineering, University of California San Diego, La Jolla, California 92093-0412, USA
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41
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Shi W, Moon CD, Leahy SC, Kang D, Froula J, Kittelmann S, Fan C, Deutsch S, Gagic D, Seedorf H, Kelly WJ, Atua R, Sang C, Soni P, Li D, Pinares-Patiño CS, McEwan JC, Janssen PH, Chen F, Visel A, Wang Z, Attwood GT, Rubin EM. Methane yield phenotypes linked to differential gene expression in the sheep rumen microbiome. Genome Res 2014; 24:1517-25. [PMID: 24907284 PMCID: PMC4158751 DOI: 10.1101/gr.168245.113] [Citation(s) in RCA: 228] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Ruminant livestock represent the single largest anthropogenic source of the potent greenhouse gas methane, which is generated by methanogenic archaea residing in ruminant digestive tracts. While differences between individual animals of the same breed in the amount of methane produced have been observed, the basis for this variation remains to be elucidated. To explore the mechanistic basis of this methane production, we measured methane yields from 22 sheep, which revealed that methane yields are a reproducible, quantitative trait. Deep metagenomic and metatranscriptomic sequencing demonstrated a similar abundance of methanogens and methanogenesis pathway genes in high and low methane emitters. However, transcription of methanogenesis pathway genes was substantially increased in sheep with high methane yields. These results identify a discrete set of rumen methanogens whose methanogenesis pathway transcription profiles correlate with methane yields and provide new targets for CH4 mitigation at the levels of microbiota composition and transcriptional regulation.
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Affiliation(s)
- Weibing Shi
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Christina D Moon
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Sinead C Leahy
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Dongwan Kang
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Jeff Froula
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Sandra Kittelmann
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Christina Fan
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Samuel Deutsch
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Dragana Gagic
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Henning Seedorf
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - William J Kelly
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Renee Atua
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Carrie Sang
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Priya Soni
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Dong Li
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | | | - John C McEwan
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Peter H Janssen
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Feng Chen
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Axel Visel
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; School of Natural Sciences, University of California, Merced, California 95343, USA
| | - Zhong Wang
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; School of Natural Sciences, University of California, Merced, California 95343, USA
| | - Graeme T Attwood
- AgResearch Limited, Grasslands Research Centre, Palmerston North 4442, New Zealand
| | - Edward M Rubin
- Department of Energy, Joint Genome Institute, Walnut Creek, California 94598, USA; Genomic Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA;
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Gieg LM, Fowler SJ, Berdugo-Clavijo C. Syntrophic biodegradation of hydrocarbon contaminants. Curr Opin Biotechnol 2014; 27:21-9. [DOI: 10.1016/j.copbio.2013.09.002] [Citation(s) in RCA: 168] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 09/04/2013] [Accepted: 09/06/2013] [Indexed: 11/30/2022]
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Meyer B, Kuehl JV, Deutschbauer AM, Arkin AP, Stahl DA. Flexibility of syntrophic enzyme systems in Desulfovibrio species ensures their adaptation capability to environmental changes. J Bacteriol 2013; 195:4900-14. [PMID: 23974031 PMCID: PMC3807489 DOI: 10.1128/jb.00504-13] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 08/20/2013] [Indexed: 12/31/2022] Open
Abstract
The mineralization of organic matter in anoxic environments relies on the cooperative activities of hydrogen producers and consumers obligately linked by interspecies metabolite exchange in syntrophic consortia that may include sulfate reducing species such as Desulfovibrio. To evaluate the metabolic flexibility of syntrophic Desulfovibrio to adapt to naturally fluctuating methanogenic environments, we studied Desulfovibrio alaskensis strain G20 grown in chemostats under respiratory and syntrophic conditions with alternative methanogenic partners, Methanococcus maripaludis and Methanospirillum hungatei, at different growth rates. Comparative whole-genome transcriptional analyses, complemented by G20 mutant strain growth experiments and physiological data, revealed a significant influence of both energy source availability (as controlled by dilution rate) and methanogen on the electron transfer systems, ratios of interspecies electron carriers, energy generating systems, and interspecies physical associations. A total of 68 genes were commonly differentially expressed under syntrophic versus respiratory lifestyle. Under low-energy (low-growth-rate) conditions, strain G20 further had the capacity to adapt to the metabolism of its methanogenic partners, as shown by its differing gene expression of enzymes involved in the direct metabolic interactions (e.g., periplasmic hydrogenases) and the ratio shift in electron carriers used for interspecies metabolite exchange (hydrogen/formate). A putative monomeric [Fe-Fe] hydrogenase and Hmc (high-molecular-weight-cytochrome c3) complex-linked reverse menaquinone (MQ) redox loop become increasingly important for the reoxidation of the lactate-/pyruvate oxidation-derived redox pair, DsrC(red) and Fd(red), relative to the Qmo-MQ-Qrc (quinone-interacting membrane-bound oxidoreductase; quinone-reducing complex) loop. Together, these data underscore the high enzymatic and metabolic adaptive flexibility that likely sustains Desulfovibrio in naturally fluctuating methanogenic environments.
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Affiliation(s)
- Birte Meyer
- Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
| | - Jennifer V. Kuehl
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Adam M. Deutschbauer
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Adam P. Arkin
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - David A. Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
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Contribution of transcriptomics to systems-level understanding of methanogenic Archaea. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2013; 2013:586369. [PMID: 23533330 PMCID: PMC3600222 DOI: 10.1155/2013/586369] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 12/24/2012] [Accepted: 01/23/2013] [Indexed: 01/25/2023]
Abstract
Methane-producing Archaea are of interest due to their contribution to atmospheric change and for their roles in technological applications including waste treatment and biofuel production. Although restricted to anaerobic environments, methanogens are found in a wide variety of habitats, where they commonly live in syntrophic relationships with bacterial partners. Owing to tight thermodynamic constraints of methanogenesis alone or in syntrophic metabolism, methanogens must carefully regulate their catabolic pathways including the regulation of RNA transcripts. The transcriptome is a dynamic and important control point in microbial systems. This paper assesses the impact of mRNA (transcriptome) studies on the understanding of methanogenesis with special consideration given to how methanogenesis is regulated to cope with nutrient limitation, environmental variability, and interactions with syntrophic partners. In comparison with traditional microarray-based transcriptome analyses, next-generation high-throughput RNA sequencing is greatly advantageous in assessing transcription start sites, the extent of 5′ untranslated regions, operonic structure, and the presence of small RNAs. We are still in the early stages of understanding RNA regulation but it is already clear that determinants beyond transcript abundance are highly relevant to the lifestyles of methanogens, requiring further study.
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