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Chen SH, Li ZT, Lai CY, Zhao HP. Enhancing reductive dechlorination of trichloroethylene in bioelectrochemical systems with conductive materials. ENVIRONMENTAL RESEARCH 2024; 261:119773. [PMID: 39128662 DOI: 10.1016/j.envres.2024.119773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2024] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 08/13/2024]
Abstract
The incorporation of conductive materials to enhance electron transfer in bioelectrochemical systems (BES) is considered a promising approach. However, the specific effects and mechanisms of these materials on trichloroethylene (TCE) reductive dechlorination in BES remains are not fully understood. This study investigated the use of magnetite nanoparticles (MNP) and biochars (BC) as coatings on biocathodes for TCE reduction. Results demonstrated that the average dechlorination rates of MNP-Biocathode (122.89 μM Cl·d-1) and BC-Biocathode (102.88 μM Cl·d-1) were greatly higher than that of Biocathode (78.17 μM Cl·d-1). Based on MATLAB calculation, the dechlorination rate exhibited a more significantly increase in TCE-to-DCE step than the other dechlorination steps. Microbial community analyses revealed an increase in the relative abundance of electroactive and dechlorinating populations (e.g., Pseudomonas, Geobacter, and Desulfovibrio) in MNP-Biocathode and BC-Biocathode. Functional gene analysis via RT-qPCR showed the expression of dehalogenase (RDase) and direct electron transfer (DET) related genes was upregulated with the addition of MNP and BC. These findings suggest that conductive materials might accelerate reductive dechlorination by enhancing DET. The difference of physicochemical characteristics (e.g. particle size and specific surface area), electron transfer enhancement mechanism between MNP and BC as well as the reduction of Fe(III) by hydrogen may explain the superior dechlorination rate observed with MNP-Biocathode.
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Affiliation(s)
- Su-Hao Chen
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Zheng-Tao Li
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Chun-Yu Lai
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
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2
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Cui B, Meng S, Wang Z, Zhu X, Chen S, Liu W, Lin C, Yan W. Mechanism underlying the sustained stimulatory effects of energization on biomethane recovery from food waste post-energization cessation. ENVIRONMENTAL RESEARCH 2024; 261:119725. [PMID: 39096988 DOI: 10.1016/j.envres.2024.119725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2024] [Revised: 07/29/2024] [Accepted: 07/31/2024] [Indexed: 08/05/2024]
Abstract
Microbial electrolysis cell-assisted anaerobic digestion represents a promising approach for enhancing methanogenesis. This study investigated the impact of varying energy levels followed by long-term open circuit on biogas recovery from food waste. The results demonstrated that a mild voltage of 0.4 V resulted in 61.7% increase in methane yield, with a methane composition reaching 78.89% vol and a remarkable reduction in digestion time by 8 days. Additionally, the facilitated effects remained after prolonged periods of open-circuit. In-depth study revealed that energization significantly enhanced organic hydrolysis, redox proteins secretion and sludge electro-activity. Microbial communities showed that the ever-present energization enriched the hydrolytic bacterium and electrophiles. Subsequent investigations also revealed the upgradation of enzyme-encoding genes associated with hydrolysis and the synthesis of flavin and its homologs (i.e. ribE, ssuE and nfrA2). These findings collectively demonstrated the enduring benefits of energization were linked to the enhanced hydrolysis and regulated mediator-mediated electron transfer pathway.
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Affiliation(s)
- Baihui Cui
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong, 518107, PR China; School of Civil Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Shengao Meng
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong, 518107, PR China
| | - Zi Wang
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong, 518107, PR China
| | - Xianzheng Zhu
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong, 518107, PR China
| | - Shuyan Chen
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong, 518107, PR China
| | - Wen Liu
- College of environment, Zhejiang University of Technology, Hangzhou, 310014, PR China
| | - Chunmian Lin
- College of environment, Zhejiang University of Technology, Hangzhou, 310014, PR China
| | - Wangwang Yan
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong, 518107, PR China.
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3
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Akram J, Song C, El Mashad HM, Chen C, Zhang R, Liu G. Advances in microbial community, mechanisms and stimulation effects of direct interspecies electron transfer in anaerobic digestion. Biotechnol Adv 2024; 76:108398. [PMID: 38914350 DOI: 10.1016/j.biotechadv.2024.108398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 06/11/2024] [Accepted: 06/21/2024] [Indexed: 06/26/2024]
Abstract
Anaerobic digestion (AD) has been proven to be an effective green technology for producing biomethane while reducing environmental pollution. The interspecies electron transfer (IET) processes in AD are critical for acetogenesis and methanogenesis, and these IET processes are carried out via mediated interspecies electron transfer (MIET) and direct interspecies electron transfer (DIET). The latter has recently become a topic of significant interest, considering its potential to allow diffusion-free electron transfer during the AD process steps. To date, different multi-heme c-type cytochromes, electrically conductive pili (e-pili), and other relevant accessories during DIET between microorganisms of different natures have been reported. Additionally, several studies have been carried out on metagenomics and metatranscriptomics for better detection of DIET, the role of DIET's stimulation in alleviating stressed conditions, such as high organic loading rates (OLR) and low pH, and the stimulation mechanisms of DIET in mixed cultures and co-cultures by various conductive materials. Keeping in view this significant research progress, this study provides in-depth insights into the DIET-active microbial community, DIET mechanisms of different species, utilization of various approaches for stimulating DIET, characterization approaches for effectively detecting DIET, and potential future research directions. This study can help accelerate the field's research progress, enable a better understanding of DIET in complex microbial communities, and allow its utilization to alleviate various inhibitions in complex AD processes.
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Affiliation(s)
- Jehangir Akram
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Chao Song
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Hamed M El Mashad
- Department of Biological and Agricultural Engineering, University of California, Davis, CA 95616, United States; Agricultural Engineering Department, Mansoura University, Egypt
| | - Chang Chen
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Ruihong Zhang
- Department of Biological and Agricultural Engineering, University of California, Davis, CA 95616, United States.
| | - Guangqing Liu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
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4
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Li Y, Yang B, Kong Y, Tao Y, Zhao Z, Li Y, Zhang Y. Correlation between intracellular electron transfer and gene expression for electrically conductive pili in electroactive bacteria during anaerobic digestion with ethanol. WATER RESEARCH 2024; 265:122307. [PMID: 39180955 DOI: 10.1016/j.watres.2024.122307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 07/24/2024] [Accepted: 08/19/2024] [Indexed: 08/27/2024]
Abstract
Ethanol feeding has been widely documented as an economical and effective strategy for establishing direct interspecies electron transfer (DIET) during anaerobic digestion. However, the mechanisms involved are still unclear, especially on correlation between intracellular electron transfer in electroactive bacteria and their gene expression for electrically conductive pili (e-pili), the most essential electrical connection component for DIET. Upon cooling from room temperature, the conductivity of digester aggregates with ethanol exponentially increased by an order of magnitude (from 45.5 to 125.4 μS/cm), whereas which with its metabolites (acetaldehyde [from 40.5 to 54.4 μS/cm] or acetate [from 32.1 to 50.4 μS/cm]) did not increase significantly. In addition, the digester aggregates only with ethanol were observed with a strong dependence of conductivity on pH. Metagenomic and metatranscriptomic analysis showed that Desulfovibrio desulfuricans was the most dominant and metabolically active bacterium that contained and highly expressed the genes for e-pili. Abundance of genes encoding the total type IV pilus assembly proteins (6.72E-04 vs 1.24E-03, P < 0.05), PilA that determined the conductive properties (2.22E-04 vs 2.44E-04, P > 0.05), and PilB that proceeded the polymerization of pilin (1.56E-04 vs 3.52E-03, P < 0.05) with ethanol was lower than that with acetaldehyde. However, transcript abundance of these genes with ethanol was generally higher than that with acetaldehyde. In comparison to acetaldehyde, ethanol increased the transcript abundance of genes encoding the key enzymes involved in NADH/NAD+ transformation on complex I and ATP synthesis on complex V in intracellular electron transport chain. The improvement of intracellular electron transfer in D. desulfuricans suggested that electrons were intracellularly energized with high energy to activate e-pili during DIET.
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Affiliation(s)
- Yuan Li
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Bowen Yang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Yaohui Kong
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Yang Tao
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Zhiqiang Zhao
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
| | - Yang Li
- School of Chemical Engineering, Ocean and Life Sciences, Dalian University of Technology, Panjin 124221, China.
| | - Yaobin Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China; School of Chemical Engineering, Ocean and Life Sciences, Dalian University of Technology, Panjin 124221, China
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Xu H, Wang M, Hei S, Qi X, Zhang X, Liang P, Fu W, Pan B, Huang X. Neglected role of iron redox cycle in direct interspecies electron transfer in anaerobic methanogenesis: Inspired from biogeochemical processes. WATER RESEARCH 2024; 262:122125. [PMID: 39053210 DOI: 10.1016/j.watres.2024.122125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 07/15/2024] [Accepted: 07/20/2024] [Indexed: 07/27/2024]
Abstract
Anaerobic digestion is an indispensable technical option towards green and low-carbon wastewater treatment, with interspecies electron transfer (IET) playing a key role in its efficiency and operational stability. The exogenous semiconductive iron oxides have been proven to effectively enhance IET, while the cognition of the physicochemical-biochemical coupling stimulatory mechanism was circumscribed and remains to be elucidated. In this study, semiconductive iron oxides, α-Fe2O3, γ-Fe2O3, α-FeOOH, and γ-FeOOH were found to significantly enhance syntrophic methanogenesis by 76.39, 72.40, 37.33, and 32.64% through redirecting the dominant IET pathway from classical interspecies hydrogen transfer to robust direct interspecies electron transfer (DIET). Their alternative roles as electron shuttles potentially substituting for c-type cytochromes were conjectured to establish an electron transport matrix associated with conductive pili. Distinguished from the conventional electron conductor mechanism of conductive Fe3O4, semiconductive iron oxides facilitated DIET intrinsically through the capacitive Fe(III/II) redox cycles coupled with secondary mineralization. The growth of Aminobacterium, Sedimentibacter, and Methanothrix was enriched and the gene copy numbers of Geobacteraceae 16S ribosomal ribonucleic acid were selectively flourished by 2.0-∼4.5- fold to establish a favorable microflora for DIET pathway. Metabolic pathways of syntrophic acetogenesis from propionate/butyrate and CO2 reduction methanogenesis were correspondingly promoted. The above findings provide new insights into the underlying mechanism of iron minerals enhancing the DIET-oriented pathway and offer paradigms for redox-mediated energy harvesting biological wastewater treatment.
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Affiliation(s)
- Hui Xu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China; State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
| | - Mingwei Wang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Shengqiang Hei
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xiang Qi
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xiaoyuan Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Peng Liang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Wanyi Fu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
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Wu Z, Ji Y, Liu G, Yu X, Shi K, Liang B, Freilich S, Jiang J. Electro-stimulation modulates syntrophic interactions in methanogenic toluene-degrading microbiota for enhanced functionality. WATER RESEARCH 2024; 260:121898. [PMID: 38865893 DOI: 10.1016/j.watres.2024.121898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 06/04/2024] [Accepted: 06/05/2024] [Indexed: 06/14/2024]
Abstract
Syntrophy achieved via microbial cooperation is vital for anaerobic hydrocarbon degradation and methanogenesis. However, limited understanding of the metabolic division of labor and electronic interactions in electro-stimulated microbiota has impeded the development of enhanced biotechnologies for degrading hydrocarbons to methane. Here, compared to the non-electro-stimulated methanogenic toluene-degrading microbiota, electro-stimulation at 800 mV promoted toluene degradation and methane production efficiencies by 11.49 %-14.76 % and 75.58 %-290.11 %, respectively. Hydrocarbon-degrading gene bamA amplification and metagenomic sequencing analyses revealed that f_Syntrophobacteraceae MAG116 may act as a toluene degrader in the non-electro-stimulated microbiota, which was proposed to establish electron syntrophy with the acetoclastic methanogen Methanosarcina spp. (or Methanothrix sp.) through e-pili or shared acetate. In the electro-stimulated microbiota, 37.22 ± 4.33 % of Desulfoprunum sp. (affiliated f_Desulfurivibrionaceae MAG10) and 58.82 ± 3.74 % of the hydrogenotrophic methanogen Methanobacterium sp. MAG74 were specifically recruited to the anode and cathode, respectively. The potential electrogen f_Desulfurivibrionaceae MAG10 engaged in interspecies electron transfer with both syntroph f_Syntrophobacteraceae MAG116 and the anode, which might be facilitated by c-type cytochromes (e.g., ImcH, OmcT, and PilZ). Moreover, upon capturing electrons from the external circuit, the hydrogen-producing electrotroph Aminidesulfovibrio sp. MAG60 could share electrons and hydrogen with the methanogen Methanobacterium sp. MAG74, which uniquely harbored hydrogenase genes ehaA-R and ehbA-P. This study elucidates the microbial interaction mechanisms underlying the enhanced metabolic efficiency of the electro-stimulated methanogenic toluene-degrading microbiota, and emphasizes the significance of metabolic and electron syntrophic interactions in maintaining the stability of microbial community functionality.
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Affiliation(s)
- Zhiming Wu
- Department of Microbiology, College of Life Sciences, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China; College of Life Sciences, Jiangxi Normal University, Nanchang 330022, China
| | - Yanhan Ji
- Department of Microbiology, College of Life Sciences, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China
| | - Guiping Liu
- Department of Microbiology, College of Life Sciences, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China
| | - Xin Yu
- Department of Microbiology, College of Life Sciences, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China
| | - Ke Shi
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Bin Liang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Shiri Freilich
- Newe-Ya'ar Research Center, Agricultural Research Organization, Ministry of Agriculture, Israel
| | - Jiandong Jiang
- Department of Microbiology, College of Life Sciences, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China.
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Song X, Yu Q, Zhang Z, Zhang Y. Enhancing the microbial advanced oxidation of P-nitrophenol in sediment through accelerating extracellular respiration with electrical stimulation. JOURNAL OF HAZARDOUS MATERIALS 2024; 475:134898. [PMID: 38878439 DOI: 10.1016/j.jhazmat.2024.134898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 06/03/2024] [Accepted: 06/11/2024] [Indexed: 06/27/2024]
Abstract
Microbial advanced oxidation, a fundamental process for pollutant degradation in nature, is limited in efficiency by the weak respiration of indigenous microorganisms. In this study, an electric field was employed to enhance microbial respiration and facilitate the microbial advanced oxidation of p-nitrophenol (PNP) in simulated wetlands with alternation of anaerobic and aerobic conditions. With intermittent air aeration, an electric field of 0.8 V promoted extracellular electron transfer to increase Fe2+ generation through dissimilatory iron reduction and the production of hydroxyl radicals (•OH) through Fenton-like reactions. As a result, the PNP removal rate of the electrically-stimulated group was higher than that of the control (72.15 % vs 46.88 %). Multiple lines of evidence demonstrated that the electrically-induced polarization of respiratory enzymes expedited proton-coupled electron transfer within the respiratory chain to accelerate microbial advanced oxidation of PNP. The polarization of respiratory enzymes with the electric field hastened proton outflow to increase cell membrane potential for adenosine triphosphate (ATP) generation, which enhanced intracellular electron transportation to benefit reactive oxygen species generation. This study provided a new method to enhance microelectrochemical remediation of the contaminant in wetlands via the combination of intermittent air aeration.
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Affiliation(s)
- Xingyuan Song
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Qilin Yu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Ziyang Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Yaobin Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
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Zhang Y, Tong M, Lu Y, Zhao F, Zhang P, Wan Z, Li P, Yuan S, Wang Y, Kappler A. Directional long-distance electron transfer from reduced to oxidized zones in the subsurface. Nat Commun 2024; 15:6576. [PMID: 39097590 PMCID: PMC11297948 DOI: 10.1038/s41467-024-50974-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/26/2024] [Indexed: 08/05/2024] Open
Abstract
Electron transfer (ET) is the fundamental redox process of life and element cycling. The ET distance is normally as short as nanometers or micrometers in the subsurface. However, the redox gradient in the subsurface is as long as centimeters or even meters. This gap triggers an intriguing question whether directional long-distance ET from reduced to oxidized zones exists along the redox gradient. By using electron-donating capacity variation as a proxy of ET, we show that ET can last over 10 cm along the redox gradient in sediment columns, through a directional long-distance ET chain from reduced to oxidized zones constituted by a series of short-distance electron hopping reactions. Microbial and chemical processes synergistically mediate the long-distance ET chain, with an estimated flux of 6.73 μmol e-/cm2 per day. This directional long-distance ET represents an overlooked but important "remote" source of electrons for local biogeochemical and environmental processes.
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Affiliation(s)
- Yanting Zhang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Man Tong
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Yuxi Lu
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Fengyi Zhao
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Peng Zhang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Zhenchen Wan
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Ping Li
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Songhu Yuan
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China.
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan, China.
| | - Yanxin Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Andreas Kappler
- Department of Geosciences, University of Tübingen, Tübingen, Germany
- Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, Tübingen, Germany
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Tang R, Zhang M, Li X. A novel strategy combining hydrogenotrophic methanogens' bioaugmentation and biochar biostimulation for simultaneous polycyclic aromatic hydrocarbon biodegradation and bioenergy recovery. RSC Adv 2024; 14:23710-23719. [PMID: 39077318 PMCID: PMC11284627 DOI: 10.1039/d4ra03732d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Accepted: 07/23/2024] [Indexed: 07/31/2024] Open
Abstract
A novel strategy combining bioaugmentation using methanogenic archaea and biostimulation using biochar was proposed for the first time to obtain simultaneous improvement of mixed PAHs' anaerobic biodegradation and bioenergy production. The results showed that the addition of PHAs immediately resulted in inhibition in methane production and accumulation of VFA, indicating that PHAs are more toxic to methanogens than the acetogenic bacteria. The coupling of biochar with hydrogenotrophic methanogen alleviated the inhibitory effects of PAHs, allowing the anaerobic fermentation system to recover its methane production capability rapidly. Compared to the Fe3+ + bioaugmentation group, the biochar + bioaugmentation group exhibited a 7.5% higher restored cumulative methane production. This coupling strategy ultimately facilitated the degradation of most PAHs, achieving a removal rate of over 90%. Moreover, the coupled biochar and bioaugmentation induced significant changes in the archaeal community structure. Direct interspecies electron guilds (i.e., Streptococcus and Methanosarcina) were enriched in the presence of biochar and bioaugmentation, responsible for prominent PAH removal and methane recovery. This study demonstrated the feasibility of simultaneous PAH biodegradation and bioenergy production using electron acceptor and enriched microorganisms.
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Affiliation(s)
- Rui Tang
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture) No. 17 Qinghua Donglu, Haidian District Beijing 100083 People's Republic of China +86 (10) 62737858 +86 (10) 62737858
| | - Min Zhang
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture) No. 17 Qinghua Donglu, Haidian District Beijing 100083 People's Republic of China +86 (10) 62737858 +86 (10) 62737858
| | - Xin Li
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture) No. 17 Qinghua Donglu, Haidian District Beijing 100083 People's Republic of China +86 (10) 62737858 +86 (10) 62737858
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10
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Zhao YC, Sha C, Zhao XM, Du JX, Zou L, Yong YC. Unnatural Direct Interspecies Electron Transfer Enabled by Living Cell-Cell Click Chemistry. Angew Chem Int Ed Engl 2024; 63:e202402318. [PMID: 38710653 DOI: 10.1002/anie.202402318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 04/29/2024] [Accepted: 05/06/2024] [Indexed: 05/08/2024]
Abstract
Direct interspecies electron transfer (DIET) is essential for maintaining the function and stability of anaerobic microbial consortia. However, only limited natural DIET modes have been identified and DIET engineering remains highly challenging. In this study, an unnatural DIET between Shewanella oneidensis MR-1 (SO, electron donating partner) and Rhodopseudomonas palustris (RP, electron accepting partner) was artificially established by a facile living cell-cell click chemistry strategy. By introducing alkyne- or azide-modified monosaccharides onto the cell outer surface of the target species, precise covalent connections between different species in high proximity were realized through a fast click chemistry reaction. Remarkably, upon covalent connection, outer cell surface C-type cytochromes mediated DIET between SO and RP was achieved and identified, although this was never realized naturally. Moreover, this connection directly shifted the natural H2 mediated interspecies electron transfer (MIET) to DIET between SO and RP, which delivered superior interspecies electron exchange efficiency. Therefore, this work demonstrated a naturally unachievable DIET and an unprecedented MIET shift to DIET accomplished by cell-cell distance engineering, offering an efficient and versatile solution for DIET engineering, which extends our understanding of DIET and opens up new avenues for DIET exploration and applications.
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Affiliation(s)
- Yi-Cheng Zhao
- Biofuel Institute and Institute for Energy Research, School of Environment and Safety Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, China
| | - Chong Sha
- Biofuel Institute and Institute for Energy Research, School of Environment and Safety Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, China
| | - Xing-Ming Zhao
- Biofuel Institute and Institute for Energy Research, School of Environment and Safety Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, China
| | - Jia-Xin Du
- Biofuel Institute and Institute for Energy Research, School of Environment and Safety Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, China
| | - Long Zou
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization from Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China
| | - Yang-Chun Yong
- Biofuel Institute and Institute for Energy Research, School of Environment and Safety Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, China
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11
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Wang P, Su Y, Wu D, Xie B. Plasticizers inhibit food waste anaerobic digestion performance by affecting microbial succession and metabolism. JOURNAL OF HAZARDOUS MATERIALS 2024; 473:134554. [PMID: 38759407 DOI: 10.1016/j.jhazmat.2024.134554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/26/2024] [Accepted: 05/04/2024] [Indexed: 05/19/2024]
Abstract
The widely existed plastic additives plasticizers in organic wastes possibly pose negative influences on anaerobic digestion (AD) performance, the direct evidence about the effects of plasticizers on AD performance is still lacking. This study evaluated the influencing mechanism of two typical plasticizers bisphenol A (BPA) and dioctyl phthalate on the whole AD process. Results indicated that plasticizers addition inhibited methane production, and the inhibiting effects were reinforced with the increase of concentration. By contrast, 50 mg/L BPA exhibited the strongest inhibition on methane production. Physicochemical analysis showed plasticizers inhibited the metabolism efficiency of soluble polysaccharide and volatile fatty acids. Microbial communities analyses suggested that plasticizers inhibited the direct interspecies electron transfer participators of methanogenic archaea (especially Methanosarcina) and syntrophic bacteria. Furthermore, plasticizers inhibited the methane metabolisms, key coenzymes (CoB, CoM, CoF420 and methanofuran) biosynthesis and the metabolisms of major organic matters. This study shed light on the effects of plasticizers on AD performance and provided new insights for assessing the influences of plasticizers or plastic additives on the disposal of organic wastes.
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Affiliation(s)
- Panliang Wang
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Henan International Joint Laboratory of Aquatic Toxicology and Health Protection, College of Life Sciences, Henan Normal University, Xinxiang, Henan 453007, PR China
| | - Yinglong Su
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Dong Wu
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Bing Xie
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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12
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Guo ZC, Cui MH, Yang CX, Dai HL, Yang TY, Zhai LZ, Chen Y, Liu WZ, Wang AJ. Electrical stress and acid orange 7 synergistically clear the blockage of electron flow in the methanogenesis of low-strength wastewater. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 20:100410. [PMID: 38572083 PMCID: PMC10987894 DOI: 10.1016/j.ese.2024.100410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 03/04/2024] [Accepted: 03/05/2024] [Indexed: 04/05/2024]
Abstract
Energy recovery from low-strength wastewater through anaerobic methanogenesis is constrained by limited substrate availability. The development of efficient methanogenic communities is critical but challenging. Here we develop a strategy to acclimate methanogenic communities using conductive carrier (CC), electrical stress (ES), and Acid Orange 7 (AO7) in a modified biofilter. The synergistic integration of CC, ES, and AO7 precipitated a remarkable 72-fold surge in methane production rate compared to the baseline. This increase was attributed to an altered methanogenic community function, independent of the continuous presence of AO7 and ES. AO7 acted as an external electron acceptor, accelerating acetogenesis from fermentation intermediates, restructuring the bacterial community, and enriching electroactive bacteria (EAB). Meanwhile, CC and ES orchestrated the assembly of the archaeal community and promoted electrotrophic methanogens, enhancing acetotrophic methanogenesis electron flow via a mechanism distinct from direct electrochemical interactions. The collective application of CC, ES, and AO7 effectively mitigated electron flow impediments in low-strength wastewater methanogenesis, achieving an additional 34% electron recovery from the substrate. This study proposes a new method of amending anaerobic digestion systems with conductive materials to advance wastewater treatment, sustainability, and energy self-sufficiency.
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Affiliation(s)
- Ze-Chong Guo
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212100, China
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Min-Hua Cui
- Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Chun-Xue Yang
- School of Geography and Tourism, Harbin University, Harbin, 150001, China
| | - Hong-Liang Dai
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212100, China
| | - Tong-Yi Yang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212100, China
| | - Lin-Zhi Zhai
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212100, China
| | - Yong Chen
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Wen-Zong Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Ai-Jie Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
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13
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Palacios PA, Philips J, Bentien A, Kofoed MVW. Relevance of extracellular electron uptake mechanisms for electromethanogenesis applications. Biotechnol Adv 2024; 73:108369. [PMID: 38685440 DOI: 10.1016/j.biotechadv.2024.108369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 02/21/2024] [Accepted: 04/24/2024] [Indexed: 05/02/2024]
Abstract
Electromethanogenesis has emerged as a biological branch of Power-to-X technologies that implements methanogenic microorganisms, as an alternative to chemical Power-to-X, to convert electrical power from renewable sources, and CO2 into methane. Unlike biomethanation processes where CO2 is converted via exogenously added hydrogen, electromethanogenesis occurs in a bioelectrochemical set-up that combines electrodes and microorganisms. Thereby, mixed, or pure methanogenic cultures catalyze the reduction of CO2 to methane via reducing equivalents supplied by a cathode. Recent advances in electromethanogenesis have been driven by interdisciplinary research at the intersection of microbiology, electrochemistry, and engineering. Integrating the knowledge acquired from these areas is essential to address the specific challenges presented by this relatively young biotechnology, which include electron transfer limitations, low energy and product efficiencies, and reactor design to enable upscaling. This review approaches electromethanogenesis from a multidisciplinary perspective, putting emphasis on the extracellular electron uptake mechanisms that methanogens use to obtain energy from cathodes, since understanding these mechanisms is key to optimize the electrochemical conditions for the development of these systems. This work summarizes the direct and indirect extracellular electron uptake mechanisms that have been elucidated to date in methanogens, along with the ones that remain unsolved. As the study of microbial corrosion, a similar bioelectrochemical process with Fe0 as electron source, has contributed to elucidate different mechanisms on how methanogens use solid electron donors, insights from both fields, biocorrosion and electromethanogenesis, are combined. Based on the repertoire of mechanisms and their potential to convert CO2 to methane, we conclude that for future applications, electromethanogenesis should focus on the indirect mechanism with H2 as intermediary. By summarizing and linking the general aspects and challenges of this process, we hope that this review serves as a guide for researchers working on electromethanogenesis in different areas of expertise to overcome the current limitations and continue with the optimization of this promising interdisciplinary technology.
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Affiliation(s)
- Paola Andrea Palacios
- Department of Biological and Chemical Engineering, Aarhus University, Gustav Wieds Vej 10C, 8200 Aarhus, Denmark.
| | - Jo Philips
- Department of Biological and Chemical Engineering, Aarhus University, Gustav Wieds Vej 10C, 8200 Aarhus, Denmark
| | - Anders Bentien
- Department of Biological and Chemical Engineering, Aarhus University, Aabogade 40, Aarhus N, 8200 Aarhus, Denmark
| | - Michael Vedel Wegener Kofoed
- Department of Biological and Chemical Engineering, Aarhus University, Gustav Wieds Vej 10C, 8200 Aarhus, Denmark
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14
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Lu Q, Li X, Rene ER, Hu Q, Qiu B. Heterogeneous g-C 3N 4/polyaniline composites enhanced the conversion of organics into methane during anaerobic wastewater treatment. ENVIRONMENTAL RESEARCH 2024; 258:119480. [PMID: 38909948 DOI: 10.1016/j.envres.2024.119480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 06/12/2024] [Accepted: 06/21/2024] [Indexed: 06/25/2024]
Abstract
In this study, g-C3N4/PANI was prepared by in situ oxidative polymerization. Graphite-phase carbon nitride (g-C3N4) with surface defects was deposited onto the surface of conductive polyaniline (PANI) to form a p-n heterojunction. This construction aimed to create an efficient heterogeneous catalyst, increasing the surface defect level and active sites of the composite, and augmenting its capability to capture and transfer extracellular electrons under anaerobic conditions. This addresses the challenge of low efficiency in direct interspecies electron transfer between bacteria and archaea during anaerobic digestion for methane production. The results showed that the prepared g-C3N4/PANI increased the CH4 yield and CH4 production rate by 82% and 96%, respectively. Notably, the conductivity and XPS test results showed that the ratio of g-C3N4 to PANI was 0.15, and the composite exhibited favorable conductivity, with a uniform distribution of pyrrolic nitrogen, pyridinic nitrogen, and graphitic nitrogen, each accounting for approximately 30%. Furthermore, g-C3N4/PANI effectively enhanced the metabolic efficiency of intermediate products such as acetate and butyrate. Analysis of the microbial community structure revealed that g-C3N4/PANI led to a significant increase in the abundance of hydrogenotrophic methanogen Methanolinea (from 48% to 64%) and enriched Clostridium (a rise of 1%) with direct interspecies electron transfer capability. Microbial community function analysis demonstrated that the addition of g-C3N4/PANI boosted the activities of key enzymes involved in anaerobic digestion, including phosphate transacetylase (PTA), phospho-butyryl transferase (PTB), and NAD-independent lactate dehydrogenase (NNLD), by 47%, 135%, and 153%, respectively. This acceleration in enzymatic activity promoted the metabolism of acetyl-CoA, butyryl-CoA, and pyruvate. Additionally, the function of ABC transporters was enhanced, thereby improving the efficiency of material and energy exchange among microorganisms.
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Affiliation(s)
- Qiaoling Lu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Xinyu Li
- Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Eldon R Rene
- IHE Delft Institute for Water Education, Department of Water Supply, Sanitation and Environmental Engineering, Westvest 7, 2601, DA, Delft, the Netherlands
| | - Qian Hu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
| | - Bin Qiu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
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15
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Bouranis JA, Tfaily MM. Inside the microbial black box: a redox-centric framework for deciphering microbial metabolism. Trends Microbiol 2024:S0966-842X(24)00134-3. [PMID: 38825550 DOI: 10.1016/j.tim.2024.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 06/04/2024]
Abstract
Microbial metabolism influences the global climate and human health and is governed by the balance between NADH and NAD+ through redox reactions. Historically, oxidative (i.e., catabolism) and reductive (i.e., fermentation) pathways have been studied in isolation, obscuring the complete metabolic picture. However, new omics technologies and biotechnological tools now allow an integrated system-level understanding of the drivers of microbial metabolism through observation and manipulation of redox reactions. Here we present perspectives on the importance of viewing microbial metabolism as the dynamic interplay between oxidative and reductive processes and apply this framework to diverse microbial systems. Additionally, we highlight novel biotechnologies to monitor and manipulate microbial redox status to control metabolism in unprecedented ways. This redox-focused systems biology framework enables a more mechanistic understanding of microbial metabolism.
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Affiliation(s)
- John A Bouranis
- Department of Environmental Science, The University of Arizona, Tucson, AZ, 85719, USA
| | - Malak M Tfaily
- Department of Environmental Science, The University of Arizona, Tucson, AZ, 85719, USA.
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16
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Valero A, Petrash DA, Kuchenbuch A, Korth B. Enriching electroactive microorganisms from ferruginous lake waters - Mind the sulfate reducers! Bioelectrochemistry 2024; 157:108661. [PMID: 38340618 DOI: 10.1016/j.bioelechem.2024.108661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 01/23/2024] [Accepted: 01/27/2024] [Indexed: 02/12/2024]
Abstract
Electroactive microorganisms are pivotal players in mineral transformation within redox interfaces characterized by pronounced oxygen and dissolved metal gradients. Yet, their systematic cultivation from such environments remains elusive. Here, we conducted an anodic enrichment using anoxic ferruginous waters from a post-mining lake as inoculum. Weak electrogenicity (j = ∼5 µA cm-2) depended on electroactive planktonic cells rather than anodic biofilms, with a preference for formate as electron donor. Addition of yeast extract decreased the lag phase but did not increase current densities. The enriched bacterial community varied depending on the substrate composition but mainly comprised of sulfate- and nitrate-reducing bacteria (e.g., Desulfatomaculum spp. and Stenotrophomonas spp.). A secondary enrichment strategy resulted in different bacterial communities composed of iron-reducing (e.g., Klebsiella spp.) and fermentative bacteria (e.g., Paeniclostridium spp.). Secondary electron microscopy and energy-dispersive X-ray spectroscopy results indicate the precipitation of sulfur- and iron-rich organomineral aggregates at the anode surface, presumably impeding current production. Our findings indicate that (i) anoxic waters containing geogenically derived metals can be used to enrich weak electricigens, and (ii) it is necessary to specifically inhibit sulfate reducers. Otherwise, sulfate reducers tend to dominate over EAM during cultivation, which can lead to anode passivation due to biomineralization.
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Affiliation(s)
- Astolfo Valero
- Institute of Soil Biology and Biogeochemistry, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic; Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Daniel A Petrash
- Institute of Soil Biology and Biogeochemistry, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic; Department of Environmental Geochemistry and Biogeochemistry, Czech Geological Survey, Prague, Czech Republic
| | - Anne Kuchenbuch
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Germany
| | - Benjamin Korth
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Germany.
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17
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Huang XL. Unveiling the role of inorganic nanoparticles in Earth's biochemical evolution through electron transfer dynamics. iScience 2024; 27:109555. [PMID: 38638571 PMCID: PMC11024932 DOI: 10.1016/j.isci.2024.109555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024] Open
Abstract
This article explores the intricate interplay between inorganic nanoparticles and Earth's biochemical history, with a focus on their electron transfer properties. It reveals how iron oxide and sulfide nanoparticles, as examples of inorganic nanoparticles, exhibit oxidoreductase activity similar to proteins. Termed "life fossil oxidoreductases," these inorganic enzymes influence redox reactions, detoxification processes, and nutrient cycling in early Earth environments. By emphasizing the structural configuration of nanoparticles and their electron conformation, including oxygen defects and metal vacancies, especially electron hopping, the article provides a foundation for understanding inorganic enzyme mechanisms. This approach, rooted in physics, underscores that life's origin and evolution are governed by electron transfer principles within the framework of chemical equilibrium. Today, these nanoparticles serve as vital biocatalysts in natural ecosystems, participating in critical reactions for ecosystem health. The research highlights their enduring impact on Earth's history, shaping ecosystems and interacting with protein metal centers through shared electron transfer dynamics, offering insights into early life processes and adaptations.
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Affiliation(s)
- Xiao-Lan Huang
- Center for Clean Water Technology, School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794-6044, USA
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18
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Zhuang X, Wang S, Wu S. Electron Transfer in the Biogeochemical Sulfur Cycle. Life (Basel) 2024; 14:591. [PMID: 38792612 PMCID: PMC11123123 DOI: 10.3390/life14050591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 04/30/2024] [Accepted: 05/02/2024] [Indexed: 05/26/2024] Open
Abstract
Microorganisms are key players in the global biogeochemical sulfur cycle. Among them, some have garnered particular attention due to their electrical activity and ability to perform extracellular electron transfer. A growing body of research has highlighted their extensive phylogenetic and metabolic diversity, revealing their crucial roles in ecological processes. In this review, we delve into the electron transfer process between sulfate-reducing bacteria and anaerobic alkane-oxidizing archaea, which facilitates growth within syntrophic communities. Furthermore, we review the phenomenon of long-distance electron transfer and potential extracellular electron transfer in multicellular filamentous sulfur-oxidizing bacteria. These bacteria, with their vast application prospects and ecological significance, play a pivotal role in various ecological processes. Subsequently, we discuss the important role of the pili/cytochrome for electron transfer and presented cutting-edge approaches for exploring and studying electroactive microorganisms. This review provides a comprehensive overview of electroactive microorganisms participating in the biogeochemical sulfur cycle. By examining their electron transfer mechanisms, and the potential ecological and applied implications, we offer novel insights into microbial sulfur metabolism, thereby advancing applications in the development of sustainable bioelectronics materials and bioremediation technologies.
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Affiliation(s)
- Xuliang Zhuang
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (X.Z.); (S.W.)
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Shijie Wang
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (X.Z.); (S.W.)
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shanghua Wu
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; (X.Z.); (S.W.)
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
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19
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Wei Y, Chen W, Hou J, Qi X, Ye M, Jiang N, Meng F, Xi B, Li M. Biogas upgrading performance and underlying mechanism in microbial electrolysis cell and anaerobic digestion integrated system. BIORESOURCE TECHNOLOGY 2024; 400:130683. [PMID: 38599352 DOI: 10.1016/j.biortech.2024.130683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 04/06/2024] [Accepted: 04/07/2024] [Indexed: 04/12/2024]
Abstract
The productivity and efficiency of two-chamber microbial electrolysis cell and anaerobic digestion integrated system (MEC-AD) were promoted by a complex of anaerobic granular sludge and iron oxides (Fe-AnGS) as inoculum. Results showed that MEC-AD with Fe-AnGS achieved biogas upgrading with a 23%-29% increase in the energy recovery rate of external circuit current and a 26%-31% decrease in volatile fatty acids. The energy recovery rate of MEC-AD remained at 52%-57%, indicating a stable operation performance. The selectively enriched methanogens and electroactive bacteria resulted in dominant hydrogenotrophic and acetoclastic methanogenesis in the cathode and anode chambers. Mechanistic analysis revealed that MEC-AD with Fe-AnGS led to specifically upregulated enzymes related to energy metabolism and electron transfer. Fe-AnGS as inoculum could improve the long-term operation performance of MEC-AD. Consequently, this study provides an efficient strategy for biogas upgrading in MEC-AD.
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Affiliation(s)
- Yufang Wei
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China
| | - Wangmi Chen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China
| | - Jiaqi Hou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China
| | - Xuejiao Qi
- Shandong Industrial Engineering Laboratory of Biogas Production & Utilization, Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, PR China
| | - Meiying Ye
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China
| | - Ning Jiang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China
| | - Fanhua Meng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China
| | - Beidou Xi
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China
| | - Mingxiao Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
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20
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Shi T, Sun D, Dang Y, Xue Y, Liu X. Enhancement of electron transfer via magnetite in nitrite-dependent anaerobic methane oxidation system. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 357:120843. [PMID: 38588621 DOI: 10.1016/j.jenvman.2024.120843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/02/2024] [Accepted: 04/02/2024] [Indexed: 04/10/2024]
Abstract
Nitrite-dependent anaerobic methane oxidation (n-DAMO) is a novel denitrification process that simultaneously further removes and utilizes methane from anaerobic effluent from wastewater treatment plants. However, the metabolic activity of n-DAMO bacteria is relative low for practical application. In this study, conductive magnetite was added into lab-scale sequencing batch reactor inoculated with n-DAMO bacteria to study the influence on n-DAMO process. With magnetite amendment, the nitrogen removal rate could reach 34.9 mg N·L-1d-1, nearly 2.5 times more than that of control group. Magnetite significantly facilitated the interspecies electron transfer and built electrically connected community with high capacitance. Enzymatic activities of electron transport chain were significantly elevated. Functional gene expression and enzyme activities associated with nitrogen and methane metabolism had been highly up-regulated. These results not only propose a useful strategy in n-DAMO application but also provide insights into the stimulating mechanism of magnetite in n-DAMO process.
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Affiliation(s)
- Tianjing Shi
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, Beijing Forestry University, Beijing, 100083, China.
| | - Dezhi Sun
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, Beijing Forestry University, Beijing, 100083, China.
| | - Yan Dang
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, Beijing Forestry University, Beijing, 100083, China.
| | - Yiting Xue
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, Beijing Forestry University, Beijing, 100083, China.
| | - Xinying Liu
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, Beijing Forestry University, Beijing, 100083, China.
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21
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Zhuo M, Quan X, Yin R, Lv K. Enhancing methane production and interspecies electron transfer of anaerobic granular sludge by the immobilization of magnetic biochar. CHEMOSPHERE 2024; 352:141332. [PMID: 38296206 DOI: 10.1016/j.chemosphere.2024.141332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/20/2024] [Accepted: 01/28/2024] [Indexed: 02/13/2024]
Abstract
Supplementation of conductive materials has been proved to be a promising approach for enhancing microbial interspecies electron transfer (IET) in anaerobic digestion systems. In this study, magnetic bamboo-based biochar was prepared at temperatures of 400-800 °C via a ball milling/carbonization method, and it immobilized in mature anaerobic granular sludge (AGS) aimed to enhance methane production by improving the IET process between syntrophic microbial communities in the AGS. Results showed that the AGS with magnetic biochar immobilization demonstrated increased glucotrophic and acetotrophic methane production by 69.54-77.56 % and 39.96-54.92 %, respectively. Magnetic biochar prepared at 800 °C with a relatively higher Fe content (0.37 g/g magnetic biochar) displayed a stronger electron charge/discharge capacity (36.66 F/g), and its immobilization into AGS promoted methane production most. The conductivity of AGS increased by 52.13-87.32 % after incorporating magnetic biochar. Furthermore, the extracellular polymeric substance (EPS) of AGS showed an increased capacitance and decreased electron transfer resistance possibly due to the binding of magnetic biochar and more riboflavin secretion in EPS, which could contribute to the accelerated IET process in the inner AGS. In addition, the immobilization of magnetic biochar could promote the production of volatile fatty acids by 15.36-22.50 %. All these improvements may jointly lead to the enhanced methane production capacity of AGS. This study provided a fundamental understanding of the role of incorporated magnetic biochar in AGS in promoting anaerobic digestion performance.
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Affiliation(s)
- Meihui Zhuo
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Xiangchun Quan
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Ruoyu Yin
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Kai Lv
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
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Ng HJ, Goh KM, Yahya A, Abdul-Wahab MF. Microbial community dynamics and functional potentials in the conversion of oil palm wastes into biomethane. 3 Biotech 2024; 14:91. [PMID: 38419684 PMCID: PMC10897112 DOI: 10.1007/s13205-024-03933-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 01/14/2024] [Indexed: 03/02/2024] Open
Abstract
Oil palm processing generates substantial waste materials rich in organic content, posing various environmental challenges. Anaerobic digestion (AD), particularly for palm oil mill effluent (POME), offers a sustainable solution, by converting waste into valuable biomethane for thermal energy or electricity generation. The synergistic activities of the AD microbiota directly affect the biomethane production, and the microbial community involved in biomethane production in POME anaerobic digestion has been reported. The composition of bacterial and archaeal communities varies under different substrate and physicochemical conditions. This review discusses the characteristics of POME, explores the microbial members engaged in each stage of AD, and elucidates the impacts of substrate and physicochemical conditions on the microbial community dynamics, with a specific focus on POME. Finally, the review outlines current research needs and provides future perspectives on optimizing the microbial communities for enhanced biomethane production from oil palm wastes.
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Affiliation(s)
- Hui Jing Ng
- Faculty of Science, Department of Biosciences, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
| | - Kian Mau Goh
- Faculty of Science, Department of Biosciences, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
| | - Adibah Yahya
- Faculty of Science, Department of Biosciences, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
| | - Mohd Firdaus Abdul-Wahab
- Faculty of Science, Department of Biosciences, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
- Taiwan-Malaysia Innovation Centre for Clean Water and Sustainable Energy (WISE Centre), 81310 UTM Johor Bahru, Johor, Malaysia
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23
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Wang N, Gao M, Liu S, Zhu W, Zhang Y, Wang X, Sun H, Guo Y, Wang Q. Electrochemical promotion of organic waste fermentation: Research advances and prospects. ENVIRONMENTAL RESEARCH 2024; 244:117422. [PMID: 37866529 DOI: 10.1016/j.envres.2023.117422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 10/13/2023] [Accepted: 10/15/2023] [Indexed: 10/24/2023]
Abstract
The current methods of treating organic waste suffer from limited resource usage and low product value. Research and development of value-added products emerges as an unavoidable trend for future growth. Electro-fermentation (EF) is a technique employed to stimulate cell proliferation, expedite microbial metabolism, and enhance the production of value-added products by administering minute voltages or currents in the fermentation system. This method represents a novel research direction lying at the crossroads of electrochemistry and biology. This article documents the current progress of EF for a range of value-added products, including gaseous fuels, organic acids, and other organics. It also presents novel value-added products, such as 1,3-propanediol, 3-hydroxypropionic acid, succinic acid, acrylic acid, and lysine. The latest research trends suggest a focus on EF for cogeneration of value-added products, studying microbial community structure and electroactive bacteria, exploring electron transfer mechanisms in EF systems, developing effective methods for nutrient recovery of nitrogen and phosphorus, optimizing EF conditions, and utilizing biosensors and artificial neural networks in this area. In this paper, an analysis is conducted on the challenges that currently exist regarding the selection of conductive materials, optimization of electrode materials, and development of bioelectrochemical system (BES) coupling processes in EF systems. The aim is to provide a reference for the development of more efficient, advanced, and value-added EF technologies. Overall, this paper aims to provide references and ideas for the development of more efficient and advanced EF technology.
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Affiliation(s)
- Nuohan Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Ming Gao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Shuo Liu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Wenbin Zhu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yuanchun Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xiaona Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Haishu Sun
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yan Guo
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Qunhui Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Tianjin College, University of Science and Technology Beijing, Tianjin, 301811, China.
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24
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Jalili P, Ala A, Nazari P, Jalili B, Ganji DD. A comprehensive review of microbial fuel cells considering materials, methods, structures, and microorganisms. Heliyon 2024; 10:e25439. [PMID: 38371992 PMCID: PMC10873675 DOI: 10.1016/j.heliyon.2024.e25439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 01/02/2024] [Accepted: 01/26/2024] [Indexed: 02/20/2024] Open
Abstract
Microbial fuel cells (MFCs) are promising for generating renewable energy from organic matter and efficient wastewater treatment. Ensuring their practical viability requires meticulous optimization and precise design. Among the critical components of MFCs, the membrane separator plays a pivotal role in segregating the anode and cathode chambers. Recent investigations have shed light on the potential benefits of membrane-less MFCs in enhancing power generation. However, it is crucial to recognize that such configurations can adversely impact the electrocatalytic activity of anode microorganisms due to increased substrate and oxygen penetration, leading to decreased coulombic efficiency. Therefore, when selecting a membrane for MFCs, it is essential to consider key factors such as internal resistance, substrate loss, biofouling, and oxygen diffusion. Addressing these considerations carefully allows researchers to advance the performance and efficiency of MFCs, facilitating their practical application in sustainable energy production and wastewater treatment. Accelerated substrate penetration could also lead to cathode clogging and bacterial inactivation, reducing the MFC's efficiency. Overall, the design and optimization of MFCs, including the selection and use of membranes, are vital for their practical application in renewable energy generation and wastewater treatment. Further research is necessary to overcome the challenges of MFCs without a membrane and to develop improved membrane materials for MFCs. This review article aims to compile comprehensive information about all constituents of the microbial fuel cell, providing practical insights for researchers examining various variables in microbial fuel cell research.
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Affiliation(s)
- Payam Jalili
- Department of Mechanical Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Amirhosein Ala
- Department of Mechanical Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Parham Nazari
- Department of Mechanical Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Bahram Jalili
- Department of Mechanical Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Davood Domiri Ganji
- Department of Mechanical Engineering, Babol Noshirvani University of Technology, P.O. Box 484, Babol, Iran
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25
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Liao Y, Zhao J, Bian J, Zhang Z, Xu S, Qin Y, Miao S, Li R, Liu R, Zhang M, Zhu W, Liu H, Qu J. From mechanism to application: Decrypting light-regulated denitrifying microbiome through geometric deep learning. IMETA 2024; 3:e162. [PMID: 38868512 PMCID: PMC10989148 DOI: 10.1002/imt2.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 10/28/2023] [Indexed: 06/14/2024]
Abstract
Regulation on denitrifying microbiomes is crucial for sustainable industrial biotechnology and ecological nitrogen cycling. The holistic genetic profiles of microbiomes can be provided by meta-omics. However, precise decryption and further applications of highly complex microbiomes and corresponding meta-omics data sets remain great challenges. Here, we combined optogenetics and geometric deep learning to form a discover-model-learn-advance (DMLA) cycle for denitrification microbiome encryption and regulation. Graph neural networks (GNNs) exhibited superior performance in integrating biological knowledge and identifying coexpression gene panels, which could be utilized to predict unknown phenotypes, elucidate molecular biology mechanisms, and advance biotechnologies. Through the DMLA cycle, we discovered the wavelength-divergent secretion system and nitrate-superoxide coregulation, realizing increasing extracellular protein production by 83.8% and facilitating nitrate removal with 99.9% enhancement. Our study showcased the potential of GNNs-empowered optogenetic approaches for regulating denitrification and accelerating the mechanistic discovery of microbiomes for in-depth research and versatile applications.
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Affiliation(s)
- Yang Liao
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Jing Zhao
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Jiyong Bian
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Ziwei Zhang
- Department of Computer Science and TechnologyTsinghua UniversityBeijingChina
| | - Siqi Xu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Yijian Qin
- Department of Computer Science and TechnologyTsinghua UniversityBeijingChina
| | - Shiyu Miao
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Rui Li
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Ruiping Liu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Meng Zhang
- School of Electronic and Information EngineeringBeihang UniversityBeijingChina
| | - Wenwu Zhu
- Department of Computer Science and TechnologyTsinghua UniversityBeijingChina
| | - Huijuan Liu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
| | - Jiuhui Qu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of EnvironmentTsinghua UniversityBeijingChina
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26
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Yang G, Lin C, Hou T, Wu X, Fang Y, Yao S, Zhuang L, Yuan Y. The survival strategy of direct interspecies electron transfer-capable coculture under electron donor-limited environments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168223. [PMID: 37926263 DOI: 10.1016/j.scitotenv.2023.168223] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 10/08/2023] [Accepted: 10/28/2023] [Indexed: 11/07/2023]
Abstract
Direct interspecies electron transfer (DIET) has been considered as an effective mechanism for interspecies electron exchange in microbial syntrophy. Understanding DIET-capable syntrophic associations under energy-limited environments is important because these conditions more closely approximate those found in natural subsurface environments than in the batch cultures in the laboratory. This study, investigated the metabolic dynamics and electron transfer mechanisms in DIET-capable syntrophic coculture of Geobacter metallireducens and Geobacter sulfurreducens under electron donor-limited condition. The wild-coculture and the mutant-coculture with a citrate synthase-deficient G. sulfurreducens exhibited similar rates of syntrophic metabolism under ethanol-limited and ethanol-replete conditions. Transcriptomic analyses revealed that, in the mutant-coculture in which interspecies electron exchange was the sole electron source for G. sulfurreducens, the transcription of genes associated with uptake hydrogenase in G. sulfurreducens were significantly repressed and thus DIET tended to be the preferred mode of interspecies electron exchange under electron donor-limited condition. To overcome electron donor limitation, c-type cytochromes in the coculture actively moved from outer membrane to extracellular environment, potentially via increased secretion of outer-membrane vesicles. These results suggested a preferred electron transfer mechanism for DIET-capable syntrophic communities' survival in the electron donor-limited environments, providing valuable insights into the biogeochemical processes mediated by DIET in natural and engineered environments.
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Affiliation(s)
- Guiqin Yang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Canfen Lin
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Tiqun Hou
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Xian Wu
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Yanlun Fang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Sijie Yao
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Li Zhuang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China.
| | - Yong Yuan
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
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27
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Zeng Y, Liu H, Chen W, Li H, Dong H, Wu H, Xu H, Sun D, Liu X, Li P, Qiu B, Dang Y. Riboflavin-loaded carbon cloth aids the anaerobic digestion of cow dung by promoting direct interspecies electron transfer. ENVIRONMENTAL RESEARCH 2024; 241:117660. [PMID: 37979928 DOI: 10.1016/j.envres.2023.117660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/29/2023] [Accepted: 11/11/2023] [Indexed: 11/20/2023]
Abstract
Cow dung generates globally due to increased beef and milk consumption, but its treatment efficiency remains low. Previous studies have shown that riboflavin-loaded conductive materials can improve anaerobic digestion through enhance direct interspecies electron transfer (DIET). However, its effect on the practical anaerobic digestion of cow dung remained unclear. In this study, carbon cloth loaded with riboflavin (carbon cloth-riboflavin) was added into an anaerobic digester treating cow dung. The carbon cloth-riboflavin reactor showed a better performance than other two reactors. The metagenomic analysis revealed that Methanothrix on the surface of the carbon cloth predominantly utilized the CO2 reduction for methane production, further enhanced after riboflavin addition, while Methanothrix in bulk sludge were using the acetate decarboxylation pathway. Furthermore, the carbon cloth-riboflavin enriched various major methanogenic pathways and activated a large number of enzymes associated with DIET. Riboflavin's presence altered the microbial communities and the abundance of functional genes relate to DIET, ultimately leading to a better performance of anaerobic digestion for cow dung.
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Affiliation(s)
- Yiwei Zeng
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Huanying Liu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Wenwen Chen
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Haoyong Li
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - He Dong
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Hongbin Wu
- Qinglin Chuangneng (Shanghai) Technology Co., Ltd, Shanghai, 201800, China
| | - Haiyu Xu
- Qinglin Chuangneng (Shanghai) Technology Co., Ltd, Shanghai, 201800, China
| | - Dezhi Sun
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Xinying Liu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Pengsong Li
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Bin Qiu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Yan Dang
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
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28
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Deng Y, Liang C, Zhu X, Zhu X, Chen L, Pan H, Xun F, Tao Y, Xing P. Methylomonadaceae was the active and dominant methanotroph in Tibet lake sediments. ISME COMMUNICATIONS 2024; 4:ycae032. [PMID: 38524764 PMCID: PMC10960969 DOI: 10.1093/ismeco/ycae032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/21/2024] [Accepted: 02/29/2024] [Indexed: 03/26/2024]
Abstract
Methane (CH4), an important greenhouse gas, significantly impacts the local and global climate. Our study focused on the composition and activity of methanotrophs residing in the lakes on the Tibetan Plateau, a hotspot for climate change research. Based on the field survey, the family Methylomonadaceae had a much higher relative abundance in freshwater lakes than in brackish and saline lakes, accounting for ~92% of total aerobic methanotrophs. Using the microcosm sediment incubation with 13CH4 followed by high throughput sequencing and metagenomic analysis, we further demonstrated that the family Methylomonadaceae was actively oxidizing CH4. Moreover, various methylotrophs, such as the genera Methylotenera and Methylophilus, were detected in the 13C-labeled DNAs, which suggested their participation in CH4-carbon sequential assimilation. The presence of CH4 metabolism, such as the tetrahydromethanopterin and the ribulose monophosphate pathways, was identified in the metagenome-assembled genomes of the family Methylomonadaceae. Furthermore, they had the potential to adapt to oxygen-deficient conditions and utilize multiple electron acceptors, such as metal oxides (Fe3+), nitrate, and nitrite, for survival in the Tibet lakes. Our findings highlighted the predominance of Methylomonadaceae and the associated microbes as active CH4 consumers, potentially regulating the CH4 emissions in the Tibet freshwater lakes. These insights contributed to understanding the plateau carbon cycle and emphasized the significance of methanotrophs in mitigating climate change.
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Affiliation(s)
- Yongcui Deng
- School of Geography, Nanjing Normal University, Nanjing 210023, Jiangsu, China
| | - Chulin Liang
- School of Geography, Nanjing Normal University, Nanjing 210023, Jiangsu, China
| | - Xiaomeng Zhu
- School of Geography, Nanjing Normal University, Nanjing 210023, Jiangsu, China
| | - Xinshu Zhu
- School of Geography, Nanjing Normal University, Nanjing 210023, Jiangsu, China
| | - Lei Chen
- School of Geography, Nanjing Normal University, Nanjing 210023, Jiangsu, China
| | - Hongan Pan
- School of Geography, Nanjing Normal University, Nanjing 210023, Jiangsu, China
| | - Fan Xun
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, Jiangsu, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Ye Tao
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, Jiangsu, China
| | - Peng Xing
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, Jiangsu, China
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29
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Liu X, Ye Y, Yang N, Cheng C, Rensing C, Jin C, Nealson KH, Zhou S. Nonelectroactive clostridium obtains extracellular electron transfer-capability after forming chimera with Geobacter. ISME COMMUNICATIONS 2024; 4:ycae058. [PMID: 38770058 PMCID: PMC11104457 DOI: 10.1093/ismeco/ycae058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/25/2024] [Accepted: 04/15/2024] [Indexed: 05/22/2024]
Abstract
Extracellular electron transfer (EET) of microorganisms is a major driver of the microbial growth and metabolism, including reactions involved in the cycling of C, N, and Fe in anaerobic environments such as soils and sediments. Understanding the mechanisms of EET, as well as knowing which organisms are EET-capable (or can become so) is fundamental to electromicrobiology and geomicrobiology. In general, Gram-positive bacteria very seldomly perform EET due to their thick non-conductive cell wall. Here, we report that a Gram-positive Clostridium intestinale (C.i) attained EET-capability for ethanol metabolism only after forming chimera with electroactive Geobacter sulfurreducens (G.s). Mechanism analyses demonstrated that the EET was possible after the cell fusion of the two species was achieved. Under these conditions, the ethanol metabolism pathway of C.i was integrated by the EET pathway of G.s, by which achieved the oxidation of ethanol for the subsequent reduction of extracellular electron acceptors in the coculture. Our study displays a new approach to perform EET for Gram-positive bacteria via recruiting the EET pathway of an electroactive bacterium, which suggests a previously unanticipated prevalence of EET in the microbial world. These findings also provide new perspectives to understand the energetic coupling between bacterial species and the ecology of interspecies mutualisms.
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Affiliation(s)
- Xing Liu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Yin Ye
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Naiming Yang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Chen Cheng
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Christopher Rensing
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Chao Jin
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China
| | - Kenneth H Nealson
- Department of Earth Science & Biological Sciences, University of Southern California, Los Angeles, CA 91030, United States
| | - Shungui Zhou
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
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30
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Nie W, He S, Lin Y, Cheng JJ, Yang C. Functional biochar in enhanced anaerobic digestion: Synthesis, performances, and mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167681. [PMID: 37839485 DOI: 10.1016/j.scitotenv.2023.167681] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 10/06/2023] [Accepted: 10/06/2023] [Indexed: 10/17/2023]
Abstract
Anaerobic digestion technology is crucial in bioenergy recovery and organic waste management. At the same time, it often encounters challenges such as low organic digestibility and inhibition of toxic substances, resulting in low biomethane yields. Biochar has recently been used in anaerobic digestion to alleviate toxicity inhibition, improve the stability of anaerobic digestion processes, and increase methane yields. However, the practical application of biochar is limited, for the properties of pristine biochar significantly affect its application in anaerobic digestion. Although much research focuses on understanding original biochar's fundamental properties and functionalization, there are few reviews on the applications of functional biochar and the effects of critical properties of pristine biochar on anaerobic digestion. This review systematically reviewed functionalization strategies, key performances, and applications of functional biochar in anaerobic digestion. The properties determining the role of biochar were reviewed, the synthesis methods of functional biochar were summarized and compared, the mechanism of functional biochar was discussed, and the factors affecting the function of functional biochar were reviewed. This review provided a comprehensive understanding of functional biochar in anaerobic digestion processes, which would be helpful for the development and applications of engineered biochar.
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Affiliation(s)
- Wenkai Nie
- College of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Gongshang University, Hangzhou, Zhejiang 310012, China; College of Environmental Science and Engineering, Hunan University, Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Shanying He
- College of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Gongshang University, Hangzhou, Zhejiang 310012, China.
| | - Yan Lin
- College of Environmental Science and Engineering, Hunan University, Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Jay J Cheng
- Academy of Environmental and Resource Sciences, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China; Department of Biological and Agricultural Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Chunping Yang
- College of Environmental Science and Engineering, Hunan University, Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China; Academy of Environmental and Resource Sciences, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China; School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China.
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31
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Zhang Y, O'Loughlin EJ, Park SY, Kwon MJ. Effects of Fe(III) (hydr)oxide mineralogy on the development of microbial communities originating from soil, surface water, groundwater, and aerosols. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:166993. [PMID: 37717756 DOI: 10.1016/j.scitotenv.2023.166993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/09/2023] [Accepted: 09/09/2023] [Indexed: 09/19/2023]
Abstract
Microbial Fe(III) reduction is a key component of the iron cycle in natural environments. However, the susceptibility of Fe(III) (hydr)oxides to microbial reduction varies depending on the mineral's crystallinity, and the type of Fe(III) (hydr)oxide in turn will affect the composition of the microbial community. We created microcosm reactors with microbial communities from four different sources (soil, surface water, groundwater, and aerosols), three Fe(III) (hydr)oxides (lepidocrocite, goethite, and hematite) as electron acceptors, and acetate as an electron donor to investigate the shaping effect of Fe(III) mineral type on the development of microbial communities. During a 10-month incubation, changes in microbial community composition, Fe(III) reduction, and acetate utilization were monitored. Overall, there was greater reduction of lepidocrocite than of goethite and hematite, and the development of microbial communities originating from the same source diverged when supplied with different Fe(III) (hydr)oxides. Furthermore, each Fe(III) mineral was associated with unique taxa that emerged from different sources. This study illustrates the taxonomic diversity of Fe(III)-reducing microbes from a broad range of natural environments.
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Affiliation(s)
- Yidan Zhang
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, South Korea
| | - Edward J O'Loughlin
- Biosciences Division, Argonne National Laboratory, Lemont, IL 60439, United States
| | - Su-Young Park
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, South Korea
| | - Man Jae Kwon
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, South Korea.
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Ma J, Yao Z, Zhao L. Comprehensive study of the combined effects of biochar and iron-based conductive materials on alleviating long chain fatty acids inhibition in anaerobic digestion. ENVIRONMENTAL RESEARCH 2023; 239:117446. [PMID: 37858695 DOI: 10.1016/j.envres.2023.117446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 10/05/2023] [Accepted: 10/17/2023] [Indexed: 10/21/2023]
Abstract
This study investigated the feasibility of alleviating the negative influence of long-chain fatty acids (LCFAs) on anaerobic digestion by biochar, micron zero-valent iron, micron-magnetite (mFe3O4) and their combination. The results demonstrate that co-addition of biochar and 6 g/L mFe3O4 (BC+6 g/L mFe3O4) increased cumulative methane production by 50% as suffered from LCFAs inhibition exerted by 2 g/L glycerol trioleate. The BC+6 g/L mFe3O4 did best in accelerating total organic carbon degradation and volatile fatty acids conversion, through successively enriching Bacteroides, Corynebacterium, and DMER64 to dominant the bacterial community. The proportion of acetotrophic Methanothrix that could alternatively reduce CO2 to methane by accepting electrons via direct interspecies electron transfer (DIET) was 0.09% with BC+6 g/L mFe3O4, nine times more than the proportion in control. Prediction of functional genes revealed the enrichment of the bacterial secretion system, indicating that BC+6 g/L mFe3O4 promoted DIET by stimulating the secretion of extracellular polymeric substances. This study provided novel insights into combining biochar and iron-based conductive materials to enhance AD performance under LCFAs inhibition.
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Affiliation(s)
- Junyi Ma
- Key Laboratory of Low-carbon Green Agriculture in North China of Ministry of Agriculture and Rural Affairs, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zonglu Yao
- Key Laboratory of Low-carbon Green Agriculture in North China of Ministry of Agriculture and Rural Affairs, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Lixin Zhao
- Key Laboratory of Low-carbon Green Agriculture in North China of Ministry of Agriculture and Rural Affairs, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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Zhao Q, Lu Y. Anaerobic oxidation of methane in terrestrial wetlands: The rate, identity and metabolism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:166049. [PMID: 37543312 DOI: 10.1016/j.scitotenv.2023.166049] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 07/19/2023] [Accepted: 08/02/2023] [Indexed: 08/07/2023]
Abstract
The recent discovery of anaerobic oxidation of methane (AOM) in freshwater ecosystems has caused a great interest in "cryptic methane cycle" in terrestrial ecosystems. Anaerobic methanotrophs appears widespread in wetland ecosystems, yet, the scope and mechanism of AOM in natural wetlands remain poorly understood. In this paper, we review the recent progress regarding the potential of AOM, the diversity and distribution, and the metabolism of anaerobic methanotrophs in wetland ecosystems. The potential of AOM determined through laboratory incubation or in situ isotopic labeling ranges from 1.4 to 704.0 nmol CH4·g-1 dry soil·d-1. It appears that the availability of electron acceptors is critical in driving different AOM in wetland soils. The environmental temperature and salinity exert a significant influence on AOM activity. Reversal methanogenesis and extracellular electron transfer are likely involved in the AOM process. In addition to anaerobic methanotrophic archaea, the direct involvement of methanogens in AOM is also probable. This review presented an overview of the rate, identity, and metabolisms to unravel the biogeochemical puzzle of AOM in wetland soils.
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Affiliation(s)
- Qingzhou Zhao
- College of Urban and Environmental Science, Peking University, Beijing 100871, PR China
| | - Yahai Lu
- College of Urban and Environmental Science, Peking University, Beijing 100871, PR China.
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Mu H, Zhao Y, Zhao C. Alleviation of ZnO nanoparticles-induced methanogenic inhibition by granular activated carbon. ENVIRONMENTAL TECHNOLOGY 2023; 44:4352-4362. [PMID: 35722663 DOI: 10.1080/09593330.2022.2091952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
A great deal of attention has been paid to the toxicology of ZnO nanoparticles (NPs) to wastewater anaerobic digestion, but few studies have assessed how to reduce their toxic effects. In this study, different dosages of granular activated carbon (GAC) were added into ZnO NPs-bearing wastewater anaerobic digestion system. It was found that although the extracellular polymeric substances resistance, which had been impaired by ZnO NPs, could not be recovered by GAC, the suppressed methane yield was greatly enhanced by promoting the conversions of butyrate and acetate into methane. GAC of 10, 20 and 30 g/L enhanced the methane yield to 69%, 79% and 97% from 42% of the control inhibited by 100 mg/L ZnO NPs. This was mainly because the adsorption of GAC could weaken the effective contact between ZnO NPs and microbes, and also adsorb some released Zn2+ that has contributed primarily to ZnO NPs toxicology. The reduced toxicity of ZnO NPs was attributed to the enrichment of the tolerant hydrogenotrophic methanogens and the direct interspecies electron transfer-linking partners of Methanosarcina with Geobacter/Syntrophomonas. These syntrophic partners potentially used GAC as a conduit to transfer electrons for methane production.
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Affiliation(s)
- Hui Mu
- School of Water Conservancy and Environment, University of Jinan, Jinan, People's Republic of China
| | - Youheng Zhao
- Shandong Academy of Environmental Science Co., Ltd., Jinan, People's Republic of China
| | - Chunhui Zhao
- School of Water Conservancy and Environment, University of Jinan, Jinan, People's Republic of China
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Chen G, Wang R, Sun M, Chen J, Iyobosa E, Zhao J. Carbon dioxide reduction to high-value chemicals in microbial electrosynthesis system: Biological conversion and regulation strategies. CHEMOSPHERE 2023; 344:140251. [PMID: 37769909 DOI: 10.1016/j.chemosphere.2023.140251] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/19/2023] [Accepted: 09/21/2023] [Indexed: 10/03/2023]
Abstract
Large emissions of atmospheric carbon dioxide (CO2) are causing climatic and environmental problems. It is crucial to capture and utilize the excess CO2 through diverse methods, among which the microbial electrosynthesis (MES) system has become an attractive and promising technology to mitigate greenhouse effects while reducing CO2 to high-value chemicals. However, the biological conversion and metabolic pathways through microbial catalysis have not been clearly elucidated. This review first introduces the main acetogenic bacteria for CO2 reduction and extracellular electron transfer mechanisms in MES. It then intensively analyzes the CO2 bioconversion pathways and carbon chain elongation processes in MES, together with energy supply and utilization. The factors affecting MES performance, including physical, chemical, and biological aspects, are summarized, and the strategies to promote and regulate bioconversion in MES are explored. Finally, challenges and perspectives concerning microbial electrochemical carbon sequestration are proposed, and suggestions for future research are also provided. This review provides theoretical foundation and technical support for further development and industrial application of MES for CO2 reduction.
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Affiliation(s)
- Gaoxiang Chen
- Key Laboratory of Yangtze Aquatic Environment (MOE), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, Shanghai, PR China
| | - Rongchang Wang
- Key Laboratory of Yangtze Aquatic Environment (MOE), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, Shanghai, PR China.
| | - Maoxin Sun
- Key Laboratory of Yangtze Aquatic Environment (MOE), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, Shanghai, PR China
| | - Jie Chen
- Key Laboratory of Yangtze Aquatic Environment (MOE), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, Shanghai, PR China
| | - Eheneden Iyobosa
- Key Laboratory of Yangtze Aquatic Environment (MOE), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, Shanghai, PR China
| | - Jianfu Zhao
- Key Laboratory of Yangtze Aquatic Environment (MOE), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, Shanghai, PR China
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Tong KTX, Tan IS, Foo HCY, Show PL, Lam MK, Wong MK. Sustainable circular biorefinery approach for novel building blocks and bioenergy production from algae using microbial fuel cell. Bioengineered 2023; 14:246-289. [PMID: 37482680 PMCID: PMC10367576 DOI: 10.1080/21655979.2023.2236842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/23/2023] [Accepted: 07/11/2023] [Indexed: 07/25/2023] Open
Abstract
The imminent need for transition to a circular biorefinery using microbial fuel cells (MFC), based on the valorization of renewable resources, will ameliorate the carbon footprint induced by industrialization. MFC catalyzed by bioelectrochemical process drew significant attention initially for its exceptional potential for integrated production of biochemicals and bioenergy. Nonetheless, the associated costly bioproduct production and slow microbial kinetics have constrained its commercialization. This review encompasses the potential and development of macroalgal biomass as a substrate in the MFC system for L-lactic acid (L-LA) and bioelectricity generation. Besides, an insight into the state-of-the-art technological advancement in the MFC system is also deliberated in detail. Investigations in recent years have shown that MFC developed with different anolyte enhances power density from several µW/m2 up to 8160 mW/m2. Further, this review provides a plausible picture of macroalgal-based L-LA and bioelectricity circular biorefinery in the MFC system for future research directions.
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Affiliation(s)
- Kevin Tian Xiang Tong
- Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University Malaysia, Miri, Sarawak, Malaysia
| | - Inn Shi Tan
- Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University Malaysia, Miri, Sarawak, Malaysia
| | - Henry Chee Yew Foo
- Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University Malaysia, Miri, Sarawak, Malaysia
| | - Pau Loke Show
- Department of Chemical Engineering, Khalifa University, Abu Dhabi, United Arab Emirates
- Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, Wenzhou University, Wenzhou, China
- Department of Chemical and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia, Semenyih, Malaysia
- Department of Sustainable Engineering, Saveetha School of Engineering, SIMATS, Chennai, India
| | - Man Kee Lam
- Chemical Engineering Department, Universiti Teknologi PETRONAS, Seri Iskandar, Perak, Malaysia
- HICoE-Centre for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, Seri Iskandar, Perak, Malaysia
| | - Mee Kee Wong
- PETRONAS Research Sdn Bhd, Kajang, Selangor, Malaysia
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Alam M, Dhar BR. Boosting thermophilic anaerobic digestion with conductive materials: Current outlook and future prospects. CHEMOSPHERE 2023; 343:140175. [PMID: 37714472 DOI: 10.1016/j.chemosphere.2023.140175] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 08/15/2023] [Accepted: 09/12/2023] [Indexed: 09/17/2023]
Abstract
Thermophilic anaerobic digestion (TAD) can provide superior process kinetics, higher methane yields, and more pathogen destruction than mesophilic anaerobic digestion (MAD). However, the broader application of TAD is still very limited, mainly due to process instabilities such as the accumulation of volatile fatty acids and ammonia inhibition in the digesters. An emerging technique to overcome the process disturbances in TAD and enhance the methane production rate is to add conductive materials (CMs) to the digester. Recent studies have revealed that CMs can promote direct interspecies electron transfer (DIET) among the microbial community, increasing the TAD performance. CMs exhibited a high potential for alleviating the accumulation of volatile fatty acids and inhibition caused by high ammonia levels. However, the types, properties, sources, and dosage of CMs can influence the process outcomes significantly, along with other process parameters such as the organic loading rates and the type of feedstocks. Therefore, it is imperative to critically review the recent research to understand the impacts of using different CMs in TAD. This review paper discusses the types and properties of CMs applied in TAD and the mechanisms of how they influence methanogenesis, digester start-up time, process disturbances, microbial community, and biogas desulfurization. The engineering challenges for industrial-scale applications and environmental risks were also discussed. Finally, critical research gaps have been identified to provide a framework for future research.
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Affiliation(s)
- Monisha Alam
- Civil and Environmental Engineering, University of Alberta, 116 Street NW, Edmonton, AB, T6G 1H9, Canada
| | - Bipro Ranjan Dhar
- Civil and Environmental Engineering, University of Alberta, 116 Street NW, Edmonton, AB, T6G 1H9, Canada.
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Wu M, Yang ZH, Jiang TB, Zhang WW, Wang ZW, Hou QX. Enhancing sludge methanogenesis with changed micro-environment of anaerobic microorganisms by Fenton iron mud. CHEMOSPHERE 2023; 341:139884. [PMID: 37648172 DOI: 10.1016/j.chemosphere.2023.139884] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 06/14/2023] [Accepted: 08/17/2023] [Indexed: 09/01/2023]
Abstract
Conductive materials have been demonstrated to enhance sludge methanogenesis, but few researches have concentrated on the interaction among conductive materials, microorganisms and their immediate living environment. In this study, Fenton iron mud with a high abundance of Fe(III) was recycled and applied in anaerobic reactors to promote anaerobic digestion (AD) process. The results show that the primary content of extracellular polymeric substances (EPS) such as polysaccharides and proteins increased significantly, possibly promoting microbial aggregation. Furthermore, with the increment of redox mediators including humic substances in EPS and Fe(III) introduced by Fenton iron mud, the direct interspecies electron transfer (DIET) between methanogens and interacting bacteria could be accelerated, which enhanced the rate of methanogenesis in anaerobic digestion (35.21 ± 4.53% increase compared to the control). The further analysis of the anaerobic microbial community confirmed the fact that Fenton iron mud enriched functional microorganisms, such as the abundance of CO2-reducing (e.g. Chloroflexi) and Fe(III)-reducing bacteria (e.g., Tepidimicrobium), thereby expediting the electron transfer reaction in the AD process via microbial DIET and dissimilatory iron reduction (DIR). This work will make it possible for using the recycled hazardous material - Fenton iron mud to improve the performance of anaerobic granular sludge during methanogenesis.
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Affiliation(s)
- Ming Wu
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Zhen-Hu Yang
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Tong-Bao Jiang
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Wen-Wen Zhang
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Zhi-Wei Wang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Qing-Xi Hou
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin, 300457, China.
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Abstract
A wide diversity of microorganisms, typically growing as biofilms, has been implicated in corrosion, a multi-trillion dollar a year problem. Aerobic microorganisms establish conditions that promote metal corrosion, but most corrosion has been attributed to anaerobes. Microbially produced organic acids, sulfide and extracellular hydrogenases can accelerate metallic iron (Fe0) oxidation coupled to hydrogen (H2) production, as can respiratory anaerobes consuming H2 as an electron donor. Some bacteria and archaea directly accept electrons from Fe0 to support anaerobic respiration, often with c-type cytochromes as the apparent outer-surface electrical contact with the metal. Functional genetic studies are beginning to define corrosion mechanisms more rigorously. Omics studies are revealing which microorganisms are associated with corrosion, but new strategies for recovering corrosive microorganisms in culture are required to evaluate corrosive capabilities and mechanisms. Interdisciplinary studies of the interactions among microorganisms and between microorganisms and metals in corrosive biofilms show promise for developing new technologies to detect and prevent corrosion. In this Review, we explore the role of microorganisms in metal corrosion and discuss potential ways to mitigate it.
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Affiliation(s)
- Dake Xu
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, China
| | - Tingyue Gu
- Department of Chemical & Biomolecular Engineering, Ohio University, Athens, OH, USA.
- Department of Biological Sciences, Ohio University, Athens, OH, USA.
- Institute for Corrosion and Multiphase Technology, Ohio University, Athens, OH, USA.
- Institute for Sustainable Energy and the Environment, Ohio University, Athens, OH, USA.
| | - Derek R Lovley
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA
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40
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Pimenta AI, Paquete CM, Morgado L, Edwards MJ, Clarke TA, Salgueiro CA, Pereira IAC, Duarte AG. Characterization of the inner membrane cytochrome ImcH from Geobacter reveals its importance for extracellular electron transfer and energy conservation. Protein Sci 2023; 32:e4796. [PMID: 37779214 PMCID: PMC10601379 DOI: 10.1002/pro.4796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 08/30/2023] [Accepted: 09/16/2023] [Indexed: 10/03/2023]
Abstract
Electroactive bacteria combine the oxidation of carbon substrates with an extracellular electron transfer (EET) process that discharges electrons to an electron acceptor outside the cell. This process involves electron transfer through consecutive redox proteins that efficiently connect the inner membrane to the cell exterior. In this study, we isolated and characterized the quinone-interacting membrane cytochrome c ImcH from Geobacter sulfurreducens, which is involved in the EET process to high redox potential acceptors. Spectroscopic and electrochemical studies show that ImcH hemes have low midpoint redox potentials, ranging from -150 to -358 mV, and connect the oxidation of the quinol-pool to EET, transferring electrons to the highly abundant periplasmic cytochrome PpcA with higher affinity than to its homologues. Despite the larger number of hemes and transmembrane helices, the ImcH structural model has similarities with the NapC/NirT/NrfH superfamily, namely the presence of a quinone-binding site on the P-side of the membrane. In addition, the first heme, likely involved on the quinol oxidation, has apparently an unusual His/Gln coordination. Our work suggests that ImcH is electroneutral and transfers electrons and protons to the same side of the membrane, contributing to the maintenance of a proton motive force and playing a central role in recycling the menaquinone pool.
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Affiliation(s)
- Andreia I. Pimenta
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
| | - Catarina M. Paquete
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
| | - Leonor Morgado
- Associate Laboratory i4HB—Institute for Health and Bioeconomy, NOVA School of Science and TechnologyUniversidade NOVA de LisboaCaparicaPortugal
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and TechnologyUniversidade NOVA de LisboaCaparicaPortugal
| | | | - Thomas A. Clarke
- Centre for Molecular and Structural Biochemistry, School of Biological SciencesUniversity of East AngliaNorwichUK
| | - Carlos A. Salgueiro
- Associate Laboratory i4HB—Institute for Health and Bioeconomy, NOVA School of Science and TechnologyUniversidade NOVA de LisboaCaparicaPortugal
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and TechnologyUniversidade NOVA de LisboaCaparicaPortugal
| | - Inês A. C. Pereira
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
| | - Américo G. Duarte
- Instituto de Tecnologia Química e Biológica António XavierUniversidade Nova de LisboaOeirasPortugal
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Frolov EN, Gavrilov SN, Toshchakov SV, Zavarzina DG. Genomic Insights into Syntrophic Lifestyle of ' Candidatus Contubernalis alkaliaceticus' Based on the Reversed Wood-Ljungdahl Pathway and Mechanism of Direct Electron Transfer. Life (Basel) 2023; 13:2084. [PMID: 37895465 PMCID: PMC10608574 DOI: 10.3390/life13102084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
The anaerobic oxidation of fatty acids and alcohols occurs near the thermodynamic limit of life. This process is driven by syntrophic bacteria that oxidize fatty acids and/or alcohols, their syntrophic partners that consume the products of this oxidation, and the pathways for interspecies electron exchange via these products or direct interspecies electron transfer (DIET). Due to the interdependence of syntrophic microorganisms on each other's metabolic activity, their isolation in pure cultures is almost impossible. Thus, little is known about their physiology, and the only available way to fill in the knowledge gap on these organisms is genomic and metabolic analysis of syntrophic cultures. Here we report the results of genome sequencing and analysis of an obligately syntrophic alkaliphilic bacterium 'Candidatus Contubernalis alkaliaceticus'. The genomic data suggest that acetate oxidation is carried out by the Wood-Ljungdahl pathway, while a bimodular respiratory system involving an Rnf complex and a Na+-dependent ATP synthase is used for energy conservation. The predicted genomic ability of 'Ca. C. alkaliaceticus' to outperform interspecies electron transfer both indirectly, via H2 or formate, and directly, via pili-like appendages of its syntrophic partner or conductive mineral particles, was experimentally demonstrated. This is the first indication of DIET in the class Dethiobacteria.
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Affiliation(s)
- Evgenii N. Frolov
- Winogradsky Institute of Microbiology, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 60 Let Oktjabrja Pr-t, 7, Bld. 2, Moscow 117312, Russia; (S.N.G.); (D.G.Z.)
| | - Sergey N. Gavrilov
- Winogradsky Institute of Microbiology, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 60 Let Oktjabrja Pr-t, 7, Bld. 2, Moscow 117312, Russia; (S.N.G.); (D.G.Z.)
| | - Stepan V. Toshchakov
- National Research Centre “Kurchatov Institute”, Akademika Kurchatova Sq., 1, Moscow 123182, Russia;
| | - Daria G. Zavarzina
- Winogradsky Institute of Microbiology, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 60 Let Oktjabrja Pr-t, 7, Bld. 2, Moscow 117312, Russia; (S.N.G.); (D.G.Z.)
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Chen SH, Li ZT, Zhao HP. Bioelectrochemical system accelerates reductive dechlorination through extracellular electron transfer networks. ENVIRONMENTAL RESEARCH 2023; 235:116645. [PMID: 37442263 DOI: 10.1016/j.envres.2023.116645] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/10/2023] [Accepted: 07/10/2023] [Indexed: 07/15/2023]
Abstract
Bioelectrochemical system is considered as a promising approach for enhanced bio-dechlorination. However, the mechanism of extracellular electron transfer in the dechlorinating consortium is still a controversial issue. In this study, bioelectrochemical systems were established with cathode potential settings at -0.30 V (vs. SHE) for trichloroethylene reduction. The average dechlorination rate (102.0 μM Cl·d-1) of biocathode was 1.36 times higher than that of open circuit (74.7 μM Cl·d-1). Electrochemical characterization via cyclic voltammetry illustrated that electrostimulation promoted electrochemical activity for redox reactions. Moreover, bacterial community structure analyses indicated electrical stimulation facilitated the enrichment of electroactive and dechlorinating populations on cathode. Metagenomic and quantitative polymerase chain reaction (qPCR) analyses revealed that direct electron transfer (via electrically conductive pili, multi-heme c-type cytochromes) between Axonexus and Desulfovibrio/cathode and indirect electron transfer (via riboflavin) for Dehalococcoides enhanced dechlorination process in BES. Overall, this study verifies the effectiveness of electrostimulated bio-dechlorination and provides novel insights into the mechanisms of dechlorination process enhancement in bioelectrochemical systems through electron transfer networks.
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Affiliation(s)
- Su-Hao Chen
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Zheng-Tao Li
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
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Mu H, Ding X, Zhu X, Wang L, Zhang Y, Zhao C. Effects of different types of granular activated carbon on methanogenesis of carbohydrate-rich food waste: Performance, microbial communities and optimization. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 895:165173. [PMID: 37385489 DOI: 10.1016/j.scitotenv.2023.165173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/25/2023] [Accepted: 06/25/2023] [Indexed: 07/01/2023]
Abstract
Granular activated carbon (GAC) supplementation is an efficient method for enhancing methane production during the anaerobic digestion of food waste, but it remains unclear which type of GAC is optimal and what potential mechanisms are involved with different types of GAC, particularly for the methanogenic system of carbohydrate-rich food waste. This study selected three commercial GAC (GAC#1, GAC#2, GAC#3) with very distinct physical and chemical properties, and investigated their impacts on the methanogenesis of carbohydrate-rich food waste with an inoculation/substrate ratio of 1. Results indicated that Fe-doped GAC#3 had a lower specific surface area but higher conductivity, yet exhibited superior performance in facilitating methanogenesis compared with GAC#1 and GAC#2, which possessed larger specific surface areas. The addition of 10 g/L GAC#3 enhanced the methane yield by 10-folds through regulating pH levels, alleviating volatile fatty acids-induced stress, enhancing key enzymatic activity, as well as enriching direct interspecies electron transfer-mediated syntrophic partner of Syntrophomonas with Methanosarcina. Furthermore, GAC#1, which had the largest specific surface area but exhibited the poorest performance, was chemically modified to enhance its ability in promoting methanogenesis. The resulting material, named MGAC#1 (Fe3O4-loaded GAC#1), exhibited superior electro-conductivity and high methane production efficiency. The methane yield of 588 mL/g-VS showed a remarkable increase of 468 % compared with GAC#1, and a modest increase of 13 % compared with GAC#3, surpassing most values reported in literature. These findings suggested that the Fe3O4-loaded GAC with lager specific surface area, was the optimal choice for the methanogenesis of sole readily acidogenic waste, providing valuable insights for the preparation of superior-quality GAC for application in biogas industry.
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Affiliation(s)
- Hui Mu
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China.
| | - Xiaofan Ding
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China
| | - Xiaoyu Zhu
- Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100864, China
| | - Liguo Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China
| | - Yongfang Zhang
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China
| | - Chunhui Zhao
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China.
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Ma K, Wang W, Guo N, Wang X, Zhang J, Jiao Y, Cui Y, Cao Z. Unravelling the resilience of magnetite assisted granules to starvation and oxytetracycline stress. JOURNAL OF HAZARDOUS MATERIALS 2023; 459:132285. [PMID: 37591174 DOI: 10.1016/j.jhazmat.2023.132285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/23/2023] [Accepted: 08/11/2023] [Indexed: 08/19/2023]
Abstract
Starvation and antibiotics pollution are two frequent perturbations during breeding wastewater treatment process. Supplying magnetite into anaerobic system has been proved efficient to accelerate microbial aggregates and alleviate the adverse effect caused by process disturbance. Nevertheless, whether these magnetite-based granules are still superior over normal granules after a long-term starvation period remains unknown, the responsiveness of these granules to antibiotics stress is also ambiguous. In current study, we investigated the resilience of magnetite-based anaerobic granular sludge (AnGS) to starvation and oxytetracycline (OTC) stress, by unravelling the variations of reactor performance, sludge properties, ARGs dissemination and microbial community. Compared with the AnGS formed without magnetite, the magnetite assisted AnGS appeared more robust defense to starvation and OTC stress. With magnetite supplement, the average methane yield after starvation recovery, 50 mg/L and 200 mg/L OTC stress was enhanced by 48.95%, 115.87% and 488.41%, respectively, accompanied with less VFAs accumulation, improved tetracycline removal rate (76.3-86.6% vs. 51.0-53.5%) and higher ARGs reduction. Meanwhile, magnetite supplement effectively ameliorated the potential sludge breakage by triggering more large granules formation. Trichococcus was considered an important impetus in maintaining the stability of magnetite-based AnGS process. By inducing more syntrophic methanogenesis partnerships, especially for hydrogenotrophic methanogenesis, magnetite ensured the improved reactor performance and stronger resilience at stress conditions.
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Affiliation(s)
- Kaili Ma
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China.
| | - Wei Wang
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China
| | - Ning Guo
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China
| | - Xiaojie Wang
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China
| | - Jie Zhang
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China
| | - Yongqi Jiao
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China
| | - Yanrui Cui
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China
| | - Zhiguo Cao
- School of Environment, Henan Normal University, People's Republic of China; Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, People's Republic of China; Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453000, Henan, People's Republic of China
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Orrantia M, Meza-Escalante ER, Burboa-Charis VA, García-Reyes RB, Atilano-Camino MM, Serrano-Palacios D, Leyva LA, Del Angel YA, Alvarez LH. Granular activated carbon enhances the anaerobic digestion of solid and liquid fractions of swine effluent at different mesophilic temperatures. Anaerobe 2023; 83:102782. [PMID: 37717850 DOI: 10.1016/j.anaerobe.2023.102782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/14/2023] [Accepted: 09/05/2023] [Indexed: 09/19/2023]
Abstract
OBJECTIVES This study evaluated the effect of particle size and dosage of granular activated carbon (GAC) on methane production from the anaerobic digestion of raw effluent (RE) of swine wastewater, and the solid (SF) and liquid (LF) fractions. The effect of temperature using the selected size and dosage of GAC was also evaluated. METHODS 60 mL of swine wastewater were inoculated with anaerobic granular sludge and GAC at different dosages and particle size. The cultures were incubated at different temperatures at 130 rpm. The kinetic parameters from experimental data were obtained using the Gompertz model. RESULTS The cultures with the LF and GAC (75-150 μm, 15 g/L) increased 1.87-fold the methane production compared to the control without GAC. The GAC at 75-150 μm showed lower lag phases and higher Rmax than the cultures with GAC at 590-600 μm. The cumulative methane production at 45 °C with the RE + GAC was 7.4-fold higher than the control. Moreover, methane production at 45 °C significantly increased with the cultures LF + GAC (6.0-fold) and SF + GAC (2.0-fold). The highest production of volatile fatty acids and ammonium was obtained at 45 °C regardless of the substrate and the addition of GAC contributed to a higher extent than the cultures lacking GAC. In most cases, the kinetic parameters at 30 °C and 37 °C were also higher with GAC. CONCLUSIONS GAC contributed to improving the fermentative and methanogenesis stages during the anaerobic digestion of fractions, evidenced by an improvement in the kinetic parameters.
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Affiliation(s)
- Miriam Orrantia
- Instituto Tecnológico de Sonora (ITSON), Departamento de Biotecnología y Ciencias Alimentarias, 5 de Febrero 818 Sur, C.P. 85000, Cuidad Obregón, Sonora, Mexico
| | - Edna R Meza-Escalante
- Instituto Tecnológico de Sonora (ITSON), Departamento de Ciencias Del Agua y Medio Ambiente, 5 de Febrero 818 Sur, C.P. 85000, Cuidad Obregón, Sonora, Mexico
| | - Vianey A Burboa-Charis
- Instituto Tecnológico de Sonora (ITSON), Departamento de Ciencias Del Agua y Medio Ambiente, 5 de Febrero 818 Sur, C.P. 85000, Cuidad Obregón, Sonora, Mexico
| | - Refugio B García-Reyes
- Universidad Autónoma de Nuevo León (UANL), Facultad de Ciencias Químicas. Av. Universidad S/N, Cd. Universitaria, San Nicolás de Los Garza, C.P. 66455, Nuevo León, Mexico
| | - Marina M Atilano-Camino
- Estación Regional Del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, Hermosillo, 83000, Mexico
| | - Denisse Serrano-Palacios
- Instituto Tecnológico de Sonora (ITSON), Departamento de Ciencias Del Agua y Medio Ambiente, 5 de Febrero 818 Sur, C.P. 85000, Cuidad Obregón, Sonora, Mexico
| | - Luis A Leyva
- Instituto Tecnológico de Sonora (ITSON), Departamento de Biotecnología y Ciencias Alimentarias, 5 de Febrero 818 Sur, C.P. 85000, Cuidad Obregón, Sonora, Mexico
| | - Yair A Del Angel
- Universidad Autónoma de Nuevo León (UANL), Facultad de Ciencias Químicas. Av. Universidad S/N, Cd. Universitaria, San Nicolás de Los Garza, C.P. 66455, Nuevo León, Mexico
| | - Luis H Alvarez
- Instituto Tecnológico de Sonora (ITSON), Departamento de Ciencias Agronómicas y Veterinarias, 5 de Febrero 818 Sur, C.P. 85000, Cuidad Obregón, Sonora, Mexico.
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Abstract
Extracellular electron transfer (EET) is the physiological process that enables the reduction or oxidation of molecules and minerals beyond the surface of a microbial cell. The first bacteria characterized with this capability were Shewanella and Geobacter, both reported to couple their growth to the reduction of iron or manganese oxide minerals located extracellularly. A key difference between EET and nearly every other respiratory activity on Earth is the need to transfer electrons beyond the cell membrane. The past decade has resolved how well-conserved strategies conduct electrons from the inner membrane to the outer surface. However, recent data suggest a much wider and less well understood collection of mechanisms enabling electron transfer to distant acceptors. This review reflects the current state of knowledge from Shewanella and Geobacter, specifically focusing on transfer across the outer membrane and beyond-an activity that enables reduction of highly variable minerals, electrodes, and even other organisms.
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Affiliation(s)
- J A Gralnick
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA; ,
| | - D R Bond
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA; ,
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Jung H, Yu H, Lee C. Direct interspecies electron transfer enables anaerobic oxidation of sulfide to elemental sulfur coupled with CO 2-reducing methanogenesis. iScience 2023; 26:107504. [PMID: 37636045 PMCID: PMC10448109 DOI: 10.1016/j.isci.2023.107504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/03/2023] [Accepted: 07/26/2023] [Indexed: 08/29/2023] Open
Abstract
Electric syntrophy between fatty acid oxidizers and methanogens through direct interspecies electron transfer (DIET) is essential for balancing acidogenesis and methanogenesis in anaerobic digestion. Promoting DIET using electrically conductive additives proved effective in enhancing methanogenesis; however, its possibility to affect other microbial redox reactions in methanogenic systems has been little studied. This study provides the first confirmation of the electro-syntrophic coupling of sulfide oxidation to S0 with CO2-reducing methanogenesis in sulfur-rich methanogenic cultures supplemented with conductive magnetite (100-700-nm particle size). The H2S content in biogas, initially exceeding 5000 ppmv, decreased to below 1 ppmv along with an accumulation of extracellular S0 (60-70 mg/L; initially <1 mg/L) at a magnetite dose of 20 mM Fe, while there were no significant changes in methane yield. A comprehensive polyphasic approach demonstrated that the S0 formation occurs through electro-syntrophic oxidation of sulfide coupled with CO2-reducing methanogenesis, involving Methanothrix as the dominant methanogen.
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Affiliation(s)
- Heejung Jung
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
| | - Hyeonjung Yu
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
| | - Changsoo Lee
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
- Graduate School of Carbon Neutrality, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
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Smith JA, Holmes DE, Woodard TL, Li Y, Liu X, Wang LY, Meier D, Schwarz IA, Lovley DR. Detrimental impact of the Geobacter metallireducens type VI secretion system on direct interspecies electron transfer. Microbiol Spectr 2023; 11:e0094123. [PMID: 37650614 PMCID: PMC10580878 DOI: 10.1128/spectrum.00941-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 07/02/2023] [Indexed: 09/01/2023] Open
Abstract
Direct interspecies electron transfer (DIET) is important in anaerobic communities of environmental and practical significance. Other than the need for close physical contact for electrical connections, the interactions of DIET partners are poorly understood. Type VI secretion systems (T6SSs) typically kill competitive microbes. Surprisingly, Geobacter metallireducens highly expressed T6SS genes when DIET-based co-cultures were initiated with Geobacter sulfurreducens. T6SS gene expression was lower when the electron shuttle anthraquinone-2,6-disulfonate was added to alleviate the need for interspecies contact. Disruption of hcp, the G. metallireducens gene for the main T6SS needle-tube protein subunit, and the most highly upregulated gene in DIET-grown cells eliminated the long lag periods required for the initiation of DIET. The mutation did not aid DIET in the presence of granular-activated carbon (GAC), consistent with the fact that DIET partners do not make physical contact when electrically connected through conductive materials. The hcp-deficient mutant also established DIET quicker with Methanosarcina barkeri. However, the mutant also reduced Fe(III) oxide faster than the wild-type strain, a phenotype not expected from the loss of the T6SS. Quantitative PCR revealed greater gene transcript abundance for key components of extracellular electron transfer in the hcp-deficient mutant versus the wild-type strain, potentially accounting for the faster Fe(III) oxide reduction and impact on DIET. The results highlight that interspecies interactions beyond electrical connections may influence DIET effectiveness. The unexpected increase in the expression of genes for extracellular electron transport components when hcp was deleted emphasizes the complexities in evaluating the electromicrobiology of highly adaptable Geobacter species. IMPORTANCE Direct interspecies electron transfer is an alternative to the much more intensively studied process of interspecies H2 transfer as a mechanism for microbes to share electrons during the cooperative metabolism of energy sources. DIET is an important process in anaerobic soils and sediments generating methane, a significant greenhouse gas. Facilitating DIET can accelerate and stabilize the conversion of organic wastes to methane biofuel in anaerobic digesters. Therefore, a better understanding of the factors controlling how fast DIET partnerships are established is expected to lead to new strategies for promoting this bioenergy process. The finding that when co-cultured with G. sulfurreducens, G. metallireducens initially expressed a type VI secretion system, a behavior not conducive to interspecies cooperation, illustrates the complexity of establishing syntrophic relationships.
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Affiliation(s)
- Jessica A. Smith
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
- Department of Biomolecular Sciences, Central Connecticut State University, New Britain, Connecticut, USA
| | - Dawn E. Holmes
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
- Department of Physical and Biological Sciences, Western New England University, Springfield, Massachusetts, USA
| | - Trevor L. Woodard
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
| | - Yang Li
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
- School of Ocean Science and Technology, Dalian University of Technology, Panjin, Liaoning, China
| | - Xinying Liu
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
| | - Li-Ying Wang
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
| | - David Meier
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
| | - Ingrid A. Schwarz
- Department of Biomolecular Sciences, Central Connecticut State University, New Britain, Connecticut, USA
| | - Derek R. Lovley
- Department of Microbiology, University of Massachusetts Amherst, Morrill IV N Science Center, Amherst, Massachusetts, USA
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Abstract
Methanogenic archaea are the only organisms that produce CH4 as part of their energy-generating metabolism. They are ubiquitous in oxidant-depleted, anoxic environments such as aquatic sediments, anaerobic digesters, inundated agricultural fields, the rumen of cattle, and the hindgut of termites, where they catalyze the terminal reactions in the degradation of organic matter. Methanogenesis is the only metabolism that is restricted to members of the domain Archaea. Here, we discuss the importance of model organisms in the history of methanogen research, including their role in the discovery of the archaea and in the biochemical and genetic characterization of methanogenesis. We also discuss outstanding questions in the field and newly emerging model systems that will expand our understanding of this uniquely archaeal metabolism.
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Affiliation(s)
- Kyle C. Costa
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA
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50
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Guberman-Pfeffer MJ. Structural Determinants of Redox Conduction Favor Robustness over Tunability in Microbial Cytochrome Nanowires. J Phys Chem B 2023; 127:7148-7161. [PMID: 37552847 DOI: 10.1021/acs.jpcb.3c02912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Structural determinants of a 103-fold variation in electrical conductivity for helical homopolymers of tetra-, hexa-, and octa-heme cytochromes (named Omc- E, S, and Z, respectively) from Geobacter sulfurreducens are investigated with the Pathways model for electron tunneling, classical molecular dynamics, and hybrid quantum/classical molecular mechanics. Thermally averaged electronic couplings for through-space heme-to-heme electron transfer in the "nanowires" computed with density functional theory are ≤0.015 eV. Pathways analyses also indicate that couplings match within a factor of 5 for all "nanowires", but some alternative tunneling routes are found involving covalent protein backbone bonds (Omc- S and Z) or propionic acid-ligating His H-bonds on adjacent hemes (OmcZ). Reorganization energies computed from electrostatic vertical energy gaps or a version of the Marcus continuum expression parameterized on the total (donor + acceptor) solvent-accessible surface area typically agree within 20% and fall within the range 0.48-0.98 eV. Reaction free energies in all three "nanowires" are ≤|0.28| eV, even though Coulombic interactions primarily tune the site redox energies by 0.7-1.2 eV. Given the conserved energetic parameters, redox conductivity differs by < 103-fold among the cytochrome "nanowires". Redox currents do not exceed 3.0 × 10-3 pA at a physiologically relevant 0.1 V bias, with the slowest electron transfers being on a (μs) timescale much faster than typical (ms) enzymatic turnovers. Thus, the "nanowires" are proposed to be functionally robust to variations in structure that provide a habitat-customized protein interface. The 30 pA to 30 nA variation in conductivity previously reported from atomic force microscopy experiments is not intrinsic to the structures and/or does not result from the physiologically relevant redox conduction mechanism.
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Affiliation(s)
- Matthew J Guberman-Pfeffer
- Department of Molecular Biophysics and Biochemistry, Yale University, 333 Cedar Street, New Haven, Connecticut 06510, United States
- Microbial Sciences Institute, Yale University, 840 West Campus Drive, West Haven, Connecticut 06516, United States
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