1
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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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2
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Fiskal A, Shuster J, Fischer S, Joshi P, Raghunatha Reddy L, Wulf SE, Kappler A, Fischer H, Herrig I, Meier J. Microbially influenced corrosion and rust tubercle formation on sheet piles in freshwater systems. Environ Microbiol 2023; 25:1796-1815. [PMID: 37145936 DOI: 10.1111/1462-2920.16393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/19/2023] [Indexed: 05/07/2023]
Abstract
The extent of how complex natural microbial communities contribute to metal corrosion is still not fully resolved, especially not for freshwater environments. In order to elucidate the key processes, we investigated rust tubercles forming massively on sheet piles along the river Havel (Germany) applying a complementary set of techniques. In-situ microsensor profiling revealed steep gradients of O2 , redox potential and pH within the tubercle. Micro-computed tomography and scanning electron microscopy showed a multi-layered inner structure with chambers and channels and various organisms embedded in the mineral matrix. Using Mössbauer spectroscopy we identified typical corrosion products including electrically conductive iron (Fe) minerals. Determination of bacterial gene copy numbers and sequencing of 16S rRNA and 18S rRNA amplicons supported a densely populated tubercle matrix with a phylogenetically and metabolically diverse microbial community. Based on our results and previous models of physic(electro)chemical reactions, we propose here a comprehensive concept of tubercle formation highlighting the crucial reactions and microorganisms involved (such as phototrophs, fermenting bacteria, dissimilatory sulphate and Fe(III) reducers) in metal corrosion in freshwaters.
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Affiliation(s)
- Annika Fiskal
- Department U2-Microbial Ecology, Federal Institute of Hydrology, Koblenz, Germany
| | - Jeremiah Shuster
- Tübingen Structural Microscopy, University of Tübingen, Tübingen, Germany
- Geomicrobiology, Department of Geosciences, University of Tübingen, Tübingen, Germany
| | - Stefan Fischer
- Tübingen Structural Microscopy, University of Tübingen, Tübingen, Germany
- Geomicrobiology, Department of Geosciences, University of Tübingen, Tübingen, Germany
| | - Prachi Joshi
- Geomicrobiology, Department of Geosciences, University of Tübingen, Tübingen, Germany
| | | | - Sven-Erik Wulf
- Section B2-Steel Structures and Corrosion Protection, Federal Waterways Engineering and Research Institute, Karlsruhe, Germany
| | - Andreas Kappler
- Tübingen Structural Microscopy, University of Tübingen, Tübingen, Germany
- Geomicrobiology, Department of Geosciences, University of Tübingen, Tübingen, Germany
- Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, Tübingen, Germany
| | - Helmut Fischer
- Department U2-Microbial Ecology, Federal Institute of Hydrology, Koblenz, Germany
| | - Ilona Herrig
- Department G3-Ecotoxicology, Federal Institute of Hydrology, Koblenz, Germany
| | - Jutta Meier
- Institute for Integrated Natural Sciences, University Koblenz, Koblenz, Germany
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3
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Sapountzaki E, Rova U, Christakopoulos P, Antonopoulou I. Renewable Hydrogen Production and Storage Via Enzymatic Interconversion of CO 2 and Formate with Electrochemical Cofactor Regeneration. CHEMSUSCHEM 2023; 16:e202202312. [PMID: 37165995 DOI: 10.1002/cssc.202202312] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 05/09/2023] [Accepted: 05/10/2023] [Indexed: 05/12/2023]
Abstract
The urgent need to reduce CO2 emissions has motivated the development of CO2 capture and utilization technologies. An emerging application is CO2 transformation into storage chemicals for clean energy carriers. Formic acid (FA), a valuable product of CO2 reduction, is an excellent hydrogen carrier. CO2 conversion to FA, followed by H2 release from FA, are conventionally chemically catalyzed. Biocatalysts offer a highly specific and less energy-intensive alternative. CO2 conversion to formate is catalyzed by formate dehydrogenase (FDH), which usually requires a cofactor to function. Several FDHs have been incorporated in bioelectrochemical systems where formate is produced by the biocathode and the cofactor is electrochemically regenerated. H2 production from formate is also catalyzed by several microorganisms possessing either formate hydrogenlyase or hydrogen-dependent CO2 reductase complexes. Combination of these two processes can lead to a CO2 -recycling cycle for H2 production, storage, and release with potentially lower environmental impact than conventional methods.
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Affiliation(s)
- Eleftheria Sapountzaki
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden
| | - Io Antonopoulou
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden
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4
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Ibrahim I, Salehmin MNI, Balachandran K, Hil Me MF, Loh KS, Abu Bakar MH, Jong BC, Lim SS. Role of microbial electrosynthesis system in CO 2 capture and conversion: a recent advancement toward cathode development. Front Microbiol 2023; 14:1192187. [PMID: 37520357 PMCID: PMC10379653 DOI: 10.3389/fmicb.2023.1192187] [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] [Received: 03/23/2023] [Accepted: 06/26/2023] [Indexed: 08/01/2023] Open
Abstract
Microbial electrosynthesis (MES) is an emerging electrochemical technology currently being researched as a CO2 sequestration method to address climate change. MES can convert CO2 from pollution or waste materials into various carbon compounds with low energy requirements using electrogenic microbes as biocatalysts. However, the critical component in this technology, the cathode, still needs to perform more effectively than other conventional CO2 reduction methods because of poor selectivity, complex metabolism pathways of microbes, and high material cost. These characteristics lead to the weak interactions of microbes and cathode electrocatalytic activities. These approaches range from cathode modification using conventional engineering approaches to new fabrication methods. Aside from cathode development, the operating procedure also plays a critical function and strategy to optimize electrosynthesis production in reducing operating costs, such as hybridization and integration of MES. If this technology could be realized, it would offer a new way to utilize excess CO2 from industries and generate profitable commodities in the future to replace fossil fuel-derived products. In recent years, several potential approaches have been tested and studied to boost the capabilities of CO2-reducing bio-cathodes regarding surface morphology, current density, and biocompatibility, which would be further elaborated. This compilation aims to showcase that the achievements of MES have significantly improved and the future direction this is going with some recommendations. Highlights - MES approach in carbon sequestration using the biotic component.- The role of microbes as biocatalysts in MES and their metabolic pathways are discussed.- Methods and materials used to modify biocathode for enhancing CO2 reduction are presented.
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Affiliation(s)
- Irwan Ibrahim
- Fuel Cell Institute, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - Mohd Nur Ikhmal Salehmin
- Institute of Sustainable Energy (ISE), Universiti Tenaga Nasional (UNITEN), Putrajaya Campus, Kajang, Malaysia
| | | | | | - Kee Shyuan Loh
- Fuel Cell Institute, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | | | - Bor Chyan Jong
- Agrotechnology and Bioscience Division, Malaysian Nuclear Agency, Kajang, Malaysia
| | - Swee Su Lim
- Fuel Cell Institute, Universiti Kebangsaan Malaysia, Bangi, Malaysia
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5
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Biel-Nielsen TL, Hatton TA, Villadsen SNB, Jakobsen JS, Bonde JL, Spormann AM, Fosbøl PL. Electrochemistry-Based CO 2 Removal Technologies. CHEMSUSCHEM 2023; 16:e202202345. [PMID: 36861656 DOI: 10.1002/cssc.202202345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/16/2023] [Indexed: 06/10/2023]
Abstract
Unprecedented increase in atmospheric CO2 levels calls for efficient, sustainable, and cost-effective technologies for CO2 removal, including both capture and conversion approaches. Current CO2 abatement is largely based on energy-intensive thermal processes with a high degree of inflexibility. In this Perspective, it is argued that future CO2 technologies will follow the general societal trend towards electrified systems. This transition is largely promoted by decreasing electricity prices, continuous expansion of renewable energy infrastructure, and breakthroughs in carbon electrotechnologies, such as electrochemically modulated amine regeneration, redox-active quinones and other species, and microbial electrosynthesis. In addition, new initiatives make electrochemical carbon capture an integrated part of Power-to-X applications, for example, by linking it to H2 production. Selected electrochemical technologies crucial for a future sustainable society are reviewed. However, significant further development of these technologies within the next decade is needed, to meet the ambitious climate goals.
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Affiliation(s)
- Tessa Lund Biel-Nielsen
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, DK-2800, Kgs. Lyngby, Denmark
| | - T Alan Hatton
- Department of Chemical Engineering, Massachusetts Institute of Technology, 02139, Cambridge, Massachusetts, USA
| | - Sebastian N B Villadsen
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, DK-2800, Kgs. Lyngby, Denmark
| | | | - Jacob L Bonde
- ESTECH A/S, Sverigesvej 13, DK-5700, Svendborg, Denmark
| | - Alfred M Spormann
- Departments of Chemical Engineering and of Civil and Environmental Engineering, Stanford University, 94305, Stanford, California, USA
- Novo Nordisk Foundation CO2 Research Center, Aarhus University, Gustav Wieds Vej 10C, Building 3135, 214, DK-8000, Aarhus, Denmark
| | - Philip L Fosbøl
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, DK-2800, Kgs. Lyngby, Denmark
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6
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Liu J, Yun S, Wang K, Liu L, An J, Ke T, Gao Y, Zhang X. Enhanced methane production in microbial electrolysis cell coupled anaerobic digestion system with MXene accelerants. BIORESOURCE TECHNOLOGY 2023; 380:129089. [PMID: 37116623 DOI: 10.1016/j.biortech.2023.129089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/17/2023] [Accepted: 04/21/2023] [Indexed: 05/09/2023]
Abstract
Accelerants can improve the anaerobic performance of a microbial electrolysis cell coupled anaerobic digestion (MEC-AD). MAX phase titanium aluminum carbide (MAX), multilayer Ti3C2TX MXene (ML-MXene) and few-layer Ti3C2TX MXene (FL-MXene) were utilized as accelerants for MEC-AD to promote CH4 production and CO2 reduction at a voltage of 0.6 V. The highest CH4 yield (358.7 mL/g VS) and the lowest CO2 yield (57.4 mL/g VS) relative to the control group (170.6 and 125.1 mL/g VS) were obtained in MEC-AD with ML-MXene (0.035 wt%). The digestates of MEC-AD with 0.035 wt% ML-MXene have superior thermal stability (40.9%) and total nutrient content (42.1 g/kg). The ML-MXene enhanced the abundances of Methanosarcina and Methanobacterium. This work highlights the possible role of MXene in promoting methanogenesis. These important findings provide a novel avenue for the development of MXene accelerants for MEC-AD systems.
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Affiliation(s)
- Jiayu Liu
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China
| | - Sining Yun
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China; Qinghai Building and Materials Research Academy Co., Ltd, the Key Lab of Plateau Building and Eco-community in Qinghai, Xining, Qinghai 810000, China.
| | - Kaijun Wang
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China
| | - Lijianan Liu
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China
| | - Jinhang An
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China
| | - Teng Ke
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China
| | - Yangyang Gao
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China
| | - Xiaoxue Zhang
- Functional Materials Laboratory (FML), School of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China
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7
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Thulluru LP, Ghangrekar MM, Chowdhury S. Progress and perspectives on microbial electrosynthesis for valorisation of CO 2 into value-added products. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 332:117323. [PMID: 36716542 DOI: 10.1016/j.jenvman.2023.117323] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/06/2023] [Accepted: 01/15/2023] [Indexed: 06/18/2023]
Abstract
Microbial electrosynthesis (MES) is a neoteric technology that facilitates biocatalysed synthesis of organic compounds with the aid of homoacetogenic bacteria, while feeding CO2 as an inorganic carbon source. Operating MES with surplus renewable electricity further enhances the sustainability of this innovative bioelectrochemical system (BES). However, several lacunae exist in the domain knowledge, stunting the widespread application of MES. Despite significant progress in this area over the past decade, the product yield efficiency is not on par with other contemporary technologies. This bottleneck can be overcome by adopting a holistic approach, i.e., applying innovative and integrated solutions to ensure a robust MES operation. Further, the widespread deployment of MES exclusively relies on its ability to mature a sessile biofilm over a biocompatible electrode, while offering minimal charge transfer resistance. Additionally, operating MES preferably at H2-generating reduction potential and valorising industrial off-gas as carbon substrate is crucial to accomplish economic sustainability. In light of the aforementioned, this review collates the latest progress in the design and development of MES-centred systems for valorisation of CO2 into value-added products. Specifically, it highlights the significance of inoculum pre-treatment for promoting biocatalytic activity and biofilm growth on the cathodic surface. In addition, it summarizes the diverse materials that are commonly used as electrodes in MES, with an emphasis on the importance of inexpensive, robust, and biocompatible electrode materials for the practical application of MES technology. Further, the review presents insights into media conditions, operational factors, and reactor configurations that affect the overall performance of MES process. Finally, the product range of MES, downstream processing requirements, and integration of MES with other environmental remediation technologies are also discussed.
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Affiliation(s)
- Lakshmi Pathi Thulluru
- School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
| | - Makarand M Ghangrekar
- Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
| | - Shamik Chowdhury
- School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India.
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8
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Recent Applications and Strategies to Enhance Performance of Electrochemical Reduction of CO2 Gas into Value-Added Chemicals Catalyzed by Whole-Cell Biocatalysts. Processes (Basel) 2023. [DOI: 10.3390/pr11030766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023] Open
Abstract
Carbon dioxide (CO2) is one of the major greenhouse gases that has been shown to cause global warming. Decreasing CO2 emissions plays an important role to minimize the impact of climate change. The utilization of CO2 gas as a cheap and sustainable source to produce higher value-added chemicals such as formic acid, methanol, methane, and acetic acid has been attracting much attention. The electrochemical reduction of CO2 catalyzed by whole-cell biocatalysts is a promising process for the production of value-added chemicals because it does not require costly enzyme purification steps and the supply of exogenous cofactors such as NADH. This study covered the recent applications of the diversity of microorganisms (pure cultures such as Shewanella oneidensis MR1, Sporomusa species, and Clostridium species and mixed cultures) as whole-cell biocatalysts to produce a wide range of value-added chemicals including methane, carboxylates (e.g., formate, acetate, butyrate, caproate), alcohols (e.g., ethanol, butanol), and bioplastics (e.g., Polyhydroxy butyrate). Remarkably, this study provided insights into the molecular levels of the proteins/enzymes (e.g., formate hydrogenases for CO2 reduction into formate and electron-transporting proteins such as c-type cytochromes) of microorganisms which are involved in the electrochemical reduction of CO2 into value-added chemicals for the suitable application of the microorganism in the chemical reduction of CO2 and enhancing the catalytic efficiency of the microorganisms toward the reaction. Moreover, this study provided some strategies to enhance the performance of the reduction of CO2 to produce value-added chemicals catalyzed by whole-cell biocatalysts.
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Hou R, Lu S, Chen S, Dou W, Liu G. The corrosion of 316L stainless steel induced by methanocossus mariplaudis through indirect electron transfer in seawater. Bioelectrochemistry 2023; 149:108310. [DOI: 10.1016/j.bioelechem.2022.108310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 10/07/2022] [Accepted: 10/16/2022] [Indexed: 12/05/2022]
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10
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Edel M, Philipp LA, Lapp J, Reiner J, Gescher J. Electron transfer of extremophiles in bioelectrochemical systems. Extremophiles 2022; 26:31. [PMID: 36222927 PMCID: PMC9556394 DOI: 10.1007/s00792-022-01279-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 10/02/2022] [Indexed: 11/30/2022]
Abstract
The interaction of bacteria and archaea with electrodes is a relatively new research field which spans from fundamental to applied research and influences interdisciplinary research in the fields of microbiology, biochemistry, biotechnology as well as process engineering. Although a substantial understanding of electron transfer processes between microbes and anodes and between microbes and cathodes has been achieved in mesophilic organisms, the mechanisms used by microbes under extremophilic conditions are still in the early stages of discovery. Here, we review our current knowledge on the biochemical solutions that evolved for the interaction of extremophilic organisms with electrodes. To this end, the available knowledge on pure cultures of extremophilic microorganisms has been compiled and the study has been extended with the help of bioinformatic analyses on the potential distribution of different electron transfer mechanisms in extremophilic microorganisms.
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Affiliation(s)
- Miriam Edel
- Institute of Technical Microbiology, Hamburg University of Technology, Hamburg, Germany
| | - Laura-Alina Philipp
- Institute of Technical Microbiology, Hamburg University of Technology, Hamburg, Germany
| | - Jonas Lapp
- Institute of Technical Microbiology, Hamburg University of Technology, Hamburg, Germany
| | - Johannes Reiner
- Karlsruhe Institute of Technology, Engler-Bunte-Institute, Karlsruhe, Germany
| | - Johannes Gescher
- Institute of Technical Microbiology, Hamburg University of Technology, Hamburg, Germany.
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Baek G, Rossi R, Saikaly PE, Logan BE. High-rate microbial electrosynthesis using a zero-gap flow cell and vapor-fed anode design. WATER RESEARCH 2022; 219:118597. [PMID: 35609490 DOI: 10.1016/j.watres.2022.118597] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/08/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
Microbial electrosynthesis (MES) cells use renewable energy to convert carbon dioxide into valuable chemical products such as methane and acetate, but chemical production rates are low and pH changes can adversely impact biocathodes. To overcome these limitations, an MES reactor was designed with a zero-gap electrode configuration with a cation exchange membrane (CEM) to achieve a low internal resistance, and a vapor-fed electrode to minimize pH changes. Liquid catholyte was pumped through a carbon felt cathode inoculated with anaerobic digester sludge, with humidified N2 gas flowing over the abiotic anode (Ti or C with a Pt catalyst) to drive water splitting. The ohmic resistance was 2.4 ± 0.5 mΩ m2, substantially lower than previous bioelectrochemical systems (20-25 mΩ m2), and the catholyte pH remained near-neutral (6.6-7.2). The MES produced a high methane production rate of 2.9 ± 1.2 L/L-d (748 mmol/m2-d, 17.4 A/m2; Ti/Pt anode) at a relatively low applied voltage of 3.1 V. In addition, acetate was produced at a rate of 940 ± 250 mmol/m2-d with 180 ± 30 mmol/m2-d for propionate. The biocathode microbial community was dominated by the methanogens of the genus Methanobrevibacter, and the acetogen of the genus Clostridium sensu stricto 1. These results demonstrate the utility of this zero-gap cell and vapor-fed anode design for increasing rates of methane and chemical production in MES.
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Affiliation(s)
- Gahyun Baek
- Department of Civil and Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, United States; Environmental Research Group, Research Institute of Industrial Science and Technology (RIST), 67 Cheongam-ro, Nam-gu, Pohang-si, Gyeongsangbuk-do, 37673 Republic of Korea
| | - Ruggero Rossi
- Department of Civil and Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, United States
| | - Pascal E Saikaly
- Environmental Science and Engineering Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia; Water Desalination and Reuse Center, King Abdullah University of Science and Technology, Saudi Arabia
| | - Bruce E Logan
- Department of Civil and Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, United States.
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Bao J, de Dios Mateos E, Scheller S. Efficient CRISPR/Cas12a-Based Genome-Editing Toolbox for Metabolic Engineering in Methanococcus maripaludis. ACS Synth Biol 2022; 11:2496-2503. [PMID: 35730587 PMCID: PMC9295151 DOI: 10.1021/acssynbio.2c00137] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
![]()
The rapid-growing
and genetically tractable methanogen Methanococcus
maripaludis is a promising host organism
for the biotechnological conversion of carbon dioxide and renewable
hydrogen to fuels and value-added products. Expansion of its product
scope through metabolic engineering necessitates reliable and efficient
genetic tools, particularly for genome edits that affect the primary
metabolism and cell growth. Here, we have designed a genome-editing
toolbox by utilizing Cas12a from Lachnospiraceae bacterium ND2006 (LbCas12a) in combination with the homology-directed repair
machinery endogenously present in M. maripaludis. This toolbox can delete target genes with a success rate of up
to 95%, despite the hyperpolyploidy of M. maripaludis. For the purpose of demonstrating a large deletion, the M. maripaludis flagellum operon (∼8.9 kbp)
was replaced by the Escherichia coli β-glucuronidase gene. To facilitate metabolic engineering
and flux balancing in M. maripaludis, the relative strength of 15 different promoters was quantified
in the presence of two common growth substrates, either formate or
carbon dioxide and hydrogen. This CRISPR/LbCas12a toolbox can be regarded
as a reliable and quick method for genome editing in a methanogen.
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Affiliation(s)
- Jichen Bao
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-02150 Espoo, Finland
| | - Enrique de Dios Mateos
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-02150 Espoo, Finland
| | - Silvan Scheller
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-02150 Espoo, Finland
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Lovley DR. Electrotrophy: Other microbial species, iron, and electrodes as electron donors for microbial respirations. BIORESOURCE TECHNOLOGY 2022; 345:126553. [PMID: 34906705 DOI: 10.1016/j.biortech.2021.126553] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/06/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
Electrotrophy, the growth of microbes on extracellular electron donors, drives important biogeochemical cycles and has practical applications. Studies of Fe(II)-based electrotrophy have provided foundational cytochrome-based mechanistic models for electron transport into cells. Direct electron uptake from other microbial species, Fe(0), or cathodes is of intense interest due to its potential roles in the production and anaerobic oxidation of methane, corrosion, and bioelectrochemical technologies. Other cells or Fe(0) can serve as the sole electron donor supporting the growth of several Geobacter and methanogen strains that are unable to use H2 as an electron donor, providing strong evidence for electrotrophy. Additional evidence for electrotrophy in Geobacter strains and Methanosarcina acetivorans is a requirement for outer-surface c-type cytochromes. However, in most instances claims for electrotrophy in anaerobes are based on indirect inference and the possibility that H2 is actually the electron donor supporting growth has not been rigorously excluded.
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Affiliation(s)
- Derek R Lovley
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang 110819, China; Department of Microbiology and Institute for Applied Life Sciences (IALS), University of Massachusetts, Amherst, MA, USA.
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14
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Finkelstein J, Swartz J, Koffas M. Bioelectrosynthesis systems. Curr Opin Biotechnol 2021; 74:211-219. [PMID: 34979469 DOI: 10.1016/j.copbio.2021.11.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/19/2021] [Accepted: 11/25/2021] [Indexed: 11/16/2022]
Abstract
Bioelectrosynthesis (BES) systems exploit extracellular electron transport pathways to augment cellular metabolism. This strategy can be used to improve the economic viability of bio-based syntheses versus conventional methods, most notably petrochemical-based syntheses. It also has the potential to reduce the carbon footprint of biomanufacturing processes. Efficient channeling of cathode-derived electrons towards biosynthesis requires a better understanding of the biological mechanisms of electron transport as well as detailed evaluation of all aspects of process performance. More advanced solutions may deploy cell free systems that use ex situ generated reducing equivalents to improve economic performance.
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Affiliation(s)
- Joshua Finkelstein
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - James Swartz
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
| | - Mattheos Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA; Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
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15
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Meneghello M, Léger C, Fourmond V. Electrochemical Studies of CO 2 -Reducing Metalloenzymes. Chemistry 2021; 27:17542-17553. [PMID: 34506631 DOI: 10.1002/chem.202102702] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Indexed: 11/07/2022]
Abstract
Only two enzymes are capable of directly reducing CO2 : CO dehydrogenase, which produces CO at a [NiFe4 S4 ] active site, and formate dehydrogenase, which produces formate at a mononuclear W or Mo active site. Both metalloenzymes are very rapid, energy-efficient and specific in terms of product. They have been connected to electrodes with two different objectives. A series of studies used protein film electrochemistry to learn about different aspects of the mechanism of these enzymes (reactivity with substrates, inhibitors…). Another series focused on taking advantage of the catalytic performance of these enzymes to build biotechnological devices, from CO2 -reducing electrodes to full photochemical devices performing artificial photosynthesis. Here, we review all these works.
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Affiliation(s)
- Marta Meneghello
- CNRS, Aix-Marseille Université, Laboratoire de Bioénergétique et Ingénierie des Protéines, UMR 7281, Institut de Microbiologie de la Méditerranée, and, Institut Microbiologie, Bioénergies et Biotechnologie, 31 chemin J. Aiguier, 13402, Marseille Cedex 20, France
| | - Christophe Léger
- CNRS, Aix-Marseille Université, Laboratoire de Bioénergétique et Ingénierie des Protéines, UMR 7281, Institut de Microbiologie de la Méditerranée, and, Institut Microbiologie, Bioénergies et Biotechnologie, 31 chemin J. Aiguier, 13402, Marseille Cedex 20, France
| | - Vincent Fourmond
- CNRS, Aix-Marseille Université, Laboratoire de Bioénergétique et Ingénierie des Protéines, UMR 7281, Institut de Microbiologie de la Méditerranée, and, Institut Microbiologie, Bioénergies et Biotechnologie, 31 chemin J. Aiguier, 13402, Marseille Cedex 20, France
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16
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Abstract
High-temperature tolerant enzymes offer multiple advantages over enzymes from mesophilic organisms for the industrial production of sustainable chemicals due to high specific activities and stabilities towards fluctuations in pH, heat, and organic solvents. The production of molecular hydrogen (H2) is of particular interest because of the multiple uses of hydrogen in energy and chemicals applications, and the ability of hydrogenase enzymes to reduce protons to H2 at a cathode. We examined the activity of Hydrogen-Dependent CO2 Reductase (HDCR) from the thermophilic bacterium Thermoanaerobacter kivui when immobilized in a redox polymer, cobaltocene-functionalized polyallylamine (Cc-PAA), on a cathode for enzyme-mediated H2 formation from electricity. The presence of Cc-PAA increased reductive current density 340-fold when used on an electrode with HDCR at 40 °C, reaching unprecedented current densities of up to 3 mA·cm−2 with minimal overpotential and high faradaic efficiency. In contrast to other hydrogenases, T. kivui HDCR showed substantial reversibility of CO-dependent inactivation, revealing an opportunity for usage in gas mixtures containing CO, such as syngas. This study highlights the important potential of combining redox polymers with novel enzymes from thermophiles for enhanced electrosynthesis.
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17
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Schuler E, Demetriou M, Shiju NR, Gruter GM. Towards Sustainable Oxalic Acid from CO 2 and Biomass. CHEMSUSCHEM 2021; 14:3636-3664. [PMID: 34324259 PMCID: PMC8519076 DOI: 10.1002/cssc.202101272] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/28/2021] [Indexed: 05/19/2023]
Abstract
To quickly and drastically reduce CO2 emissions and meet our ambitions of a circular future, we need to develop carbon capture and storage (CCS) and carbon capture and utilization (CCU) to deal with the CO2 that we produce. While we have many alternatives to replace fossil feedstocks for energy generation, for materials such as plastics we need carbon. The ultimate circular carbon feedstock would be CO2 . A promising route is the electrochemical reduction of CO2 to formic acid derivatives that can subsequently be converted into oxalic acid. Oxalic acid is a potential new platform chemical for material production as useful monomers such as glycolic acid can be derived from it. This work is part of the European Horizon 2020 project "Ocean" in which all these steps are developed. This Review aims to highlight new developments in oxalic acid production processes with a focus on CO2 -based routes. All available processes are critically assessed and compared on criteria including overall process efficiency and triple bottom line sustainability.
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Affiliation(s)
- Eric Schuler
- Van ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
| | - Marilena Demetriou
- Van ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
| | - N. Raveendran Shiju
- Van ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
| | - Gert‐Jan M. Gruter
- Van ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
- Avantium Chemicals BVZekeringstraat 291014 BVAmsterdamThe Netherlands
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18
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Palacios PA, Francis WR, Rotaru AE. A Win-Loss Interaction on Fe 0 Between Methanogens and Acetogens From a Climate Lake. Front Microbiol 2021; 12:638282. [PMID: 34054747 PMCID: PMC8158942 DOI: 10.3389/fmicb.2021.638282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 03/29/2021] [Indexed: 12/23/2022] Open
Abstract
Diverse physiological groups congregate into environmental corrosive biofilms, yet the interspecies interactions between these corrosive physiological groups are seldom examined. We, therefore, explored Fe0-dependent cross-group interactions between acetogens and methanogens from lake sediments. On Fe0, acetogens were more corrosive and metabolically active when decoupled from methanogens, whereas methanogens were more metabolically active when coupled with acetogens. This suggests an opportunistic (win-loss) interaction on Fe0 between acetogens (loss) and methanogens (win). Clostridia and Methanobacterium were the major candidates doing acetogenesis and methanogenesis after four transfers (metagenome sequencing) and the only groups detected after 11 transfers (amplicon sequencing) on Fe0. Since abiotic H2 failed to explain the high metabolic rates on Fe0, we examined whether cell exudates (spent media filtrate) promoted the H2-evolving reaction on Fe0 above abiotic controls. Undeniably, spent media filtrate generated three- to four-fold more H2 than abiotic controls, which could be partly explained by thermolabile enzymes and partly by non-thermolabile constituents released by cells. Next, we examined the metagenome for candidate enzymes/shuttles that could catalyze H2 evolution from Fe0 and found candidate H2-evolving hydrogenases and an almost complete pathway for flavin biosynthesis in Clostridium. Clostridial ferredoxin-dependent [FeFe]-hydrogenases may be catalyzing the H2-evolving reaction on Fe0, explaining the significant H2 evolved by spent media exposed to Fe0. It is typical of Clostridia to secrete enzymes and other small molecules for lytic purposes. Here, they may secrete such molecules to enhance their own electron uptake from extracellular electron donors but indirectly make their H2-consuming neighbors-Methanobacterium-fare five times better in their presence. The particular enzymes and constituents promoting H2 evolution from Fe0 remain to be determined. However, we postulate that in a static environment like corrosive crust biofilms in lake sediments, less corrosive methanogens like Methanobacterium could extend corrosion long after acetogenesis ceased, by exploiting the constituents secreted by acetogens.
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Affiliation(s)
| | | | - Amelia-Elena Rotaru
- Nordcee, Department of Biology, University of Southern Denmark, Odense, Denmark
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19
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Ruth JC, Spormann AM. Enzyme Electrochemistry for Industrial Energy Applications—A Perspective on Future Areas of Focus. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00708] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- John C. Ruth
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
| | - Alfred M. Spormann
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
- Department of Civil and Environmental Engineering, Stanford University, Stanford, California 94305, United States
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20
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Analysis of a Methanogen and an Actinobacterium Dominating the Thermophilic Microbial Community of an Electromethanogenic Biocathode. ACTA ACUST UNITED AC 2021; 2021:8865133. [PMID: 33746613 PMCID: PMC7943316 DOI: 10.1155/2021/8865133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 02/09/2021] [Accepted: 02/15/2021] [Indexed: 12/13/2022]
Abstract
Electromethanogenesis refers to the bioelectrochemical synthesis of methane from CO2 by biocathodes. In an electromethanogenic system using thermophilic microorganisms, metagenomic analysis along with quantitative real-time polymerase chain reaction and fluorescence in situ hybridization revealed that the biocathode microbiota was dominated by the methanogen Methanothermobacter sp. strain EMTCatA1 and the actinobacterium Coriobacteriaceae sp. strain EMTCatB1. RNA sequencing was used to compare the transcriptome profiles of each strain at the methane-producing biocathodes with those in an open circuit and with the methanogenesis inhibitor 2-bromoethanesulfonate (BrES). For the methanogen, genes related to hydrogenotrophic methanogenesis were highly expressed in a manner similar to those observed under H2-limited conditions. For the actinobacterium, the expression profiles of genes encoding multiheme c-type cytochromes and membrane-bound oxidoreductases suggested that the actinobacterium directly takes up electrons from the electrode. In both strains, various stress-related genes were commonly induced in the open-circuit biocathodes and biocathodes with BrES. This study provides a molecular inventory of the dominant species of an electromethanogenic biocathode with functional insights and therefore represents the first multiomics characterization of an electromethanogenic biocathode.
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21
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Gao K, Lu Y. Putative Extracellular Electron Transfer in Methanogenic Archaea. Front Microbiol 2021; 12:611739. [PMID: 33828536 PMCID: PMC8019784 DOI: 10.3389/fmicb.2021.611739] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 03/03/2021] [Indexed: 11/14/2022] Open
Abstract
It has been suggested that a few methanogens are capable of extracellular electron transfers. For instance, Methanosarcina barkeri can directly capture electrons from the coexisting microbial cells of other species. Methanothrix harundinacea and Methanosarcina horonobensis retrieve electrons from Geobacter metallireducens via direct interspecies electron transfer (DIET). Recently, Methanobacterium, designated strain YSL, has been found to grow via DIET in the co-culture with Geobacter metallireducens. Methanosarcina acetivorans can perform anaerobic methane oxidation and respiratory growth relying on Fe(III) reduction through the extracellular electron transfer. Methanosarcina mazei is capable of electromethanogenesis under the conditions where electron-transfer mediators like H2 or formate are limited. The membrane-bound multiheme c-type cytochromes (MHC) and electrically-conductive cellular appendages have been assumed to mediate the extracellular electron transfer in bacteria like Geobacter and Shewanella species. These molecules or structures are rare but have been recently identified in a few methanogens. Here, we review the current state of knowledge for the putative extracellular electron transfers in methanogens and highlight the opportunities and challenges for future research.
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Affiliation(s)
- Kailin Gao
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yahai Lu
- College of Urban and Environmental Sciences, Peking University, Beijing, China
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22
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Lekbach Y, Liu T, Li Y, Moradi M, Dou W, Xu D, Smith JA, Lovley DR. Microbial corrosion of metals: The corrosion microbiome. Adv Microb Physiol 2021; 78:317-390. [PMID: 34147188 DOI: 10.1016/bs.ampbs.2021.01.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Microbially catalyzed corrosion of metals is a substantial economic concern. Aerobic microbes primarily enhance Fe0 oxidation through indirect mechanisms and their impact appears to be limited compared to anaerobic microbes. Several anaerobic mechanisms are known to accelerate Fe0 oxidation. Microbes can consume H2 abiotically generated from the oxidation of Fe0. Microbial H2 removal makes continued Fe0 oxidation more thermodynamically favorable. Extracellular hydrogenases further accelerate Fe0 oxidation. Organic electron shuttles such as flavins, phenazines, and possibly humic substances may replace H2 as the electron carrier between Fe0 and cells. Direct Fe0-to-microbe electron transfer is also possible. Which of these anaerobic mechanisms predominates in model pure culture isolates is typically poorly documented because of a lack of functional genetic studies. Microbial mechanisms for Fe0 oxidation may also apply to some other metals. An ultimate goal of microbial metal corrosion research is to develop molecular tools to diagnose the occurrence, mechanisms, and rates of metal corrosion to guide the implementation of the most effective mitigation strategies. A systems biology approach that includes innovative isolation and characterization methods, as well as functional genomic investigations, will be required in order to identify the diagnostic features to be gleaned from meta-omic analysis of corroding materials. A better understanding of microbial metal corrosion mechanisms is expected to lead to new corrosion mitigation strategies. The understanding of the corrosion microbiome is clearly in its infancy, but interdisciplinary electrochemical, microbiological, and molecular tools are available to make rapid progress in this field.
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Affiliation(s)
- Yassir Lekbach
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, China; Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China
| | - Tao Liu
- College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai, China
| | - Yingchao Li
- Beijing Key Laboratory of Failure, Corrosion and Protection of Oil/Gas Facility Materials, College of New Energy and Materials, China University of Petroleum-Beijing, Beijing, China
| | - Masoumeh Moradi
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, China; Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China
| | - Wenwen Dou
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
| | - Dake Xu
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, China; Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China.
| | - Jessica A Smith
- Department of Biomolecular Sciences, Central Connecticut State University, New Britain, CT, United States
| | - 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, United States.
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23
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Jung T, Hackbarth M, Horn H, Gescher J. Improving the Cathodic Biofilm Growth Capabilities of Kyrpidia spormannii EA-1 by Undirected Mutagenesis. Microorganisms 2020; 9:microorganisms9010077. [PMID: 33396703 PMCID: PMC7823960 DOI: 10.3390/microorganisms9010077] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/23/2020] [Accepted: 12/25/2020] [Indexed: 12/18/2022] Open
Abstract
The biotechnological usage of carbon dioxide has become a relevant aim for future processes. Microbial electrosynthesis is a rather new technique to energize biological CO2 fixation with the advantage to establish a continuous process based on a cathodic biofilm that is supplied with renewable electrical energy as electron and energy source. In this study, the recently characterized cathodic biofilm forming microorganism Kyrpidia spormannii strain EA-1 was used in an adaptive laboratory evolution experiment to enhance its cathodic biofilm growth capabilities. At the end of the experiment, the adapted cathodic population exhibited an up to fourfold higher biofilm accumulation rate, as well as faster substratum coverage and a more uniform biofilm morphology compared to the progenitor strain. Genomic variant analysis revealed a genomically heterogeneous population with genetic variations occurring to various extends throughout the community. Via the conducted analysis we identified possible targets for future genetic engineering with the aim to further optimize cathodic growth. Moreover, the results assist in elucidating the underlying processes that enable cathodic biofilm formation.
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Affiliation(s)
- Tobias Jung
- Department of Applied Biology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Max Hackbarth
- Engler-Bunte-Institut, Chair of Water Chemistry and Water Technology, Karlsruhe Institute of Technology (KIT), Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany
| | - Harald Horn
- Engler-Bunte-Institut, Chair of Water Chemistry and Water Technology, Karlsruhe Institute of Technology (KIT), Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany
| | - Johannes Gescher
- Department of Applied Biology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
- Institute for Biological Interfaces, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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24
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Lienemann M. Molecular mechanisms of electron transfer employed by native proteins and biological-inorganic hybrid systems. Comput Struct Biotechnol J 2020; 19:206-213. [PMID: 33425252 PMCID: PMC7772364 DOI: 10.1016/j.csbj.2020.12.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 12/03/2020] [Accepted: 12/05/2020] [Indexed: 11/19/2022] Open
Abstract
Recent advances in enzymatic electrosynthesis of desired chemicals in biological-inorganic hybrid systems has generated interest because it can use renewable energy inputs and employs highly specific catalysts that are active at ambient conditions. However, the development of such innovative processes is currently limited by a deficient understanding of the molecular mechanisms involved in electrode-based electron transfer and biocatalysis. Mechanistic studies of non-electrosynthetic electron transferring proteins have provided a fundamental understanding of the processes that take place during enzymatic electrosynthesis. Thus, they may help explain how redox proteins stringently control the reduction potential of the transferred electron and efficiently transfer it to a specific electron acceptor. The redox sites at which electron donor oxidation and electron acceptor reduction take place are typically located in distant regions of the redox protein complex and are electrically connected by an array of closely spaced cofactors. These groups function as electron relay centers and are shielded from the surrounding environment by the electrically insulating apoporotein. In this matrix, electrons travel via electron tunneling, i.e. hopping between neighboring cofactors, over impressive distances of upto several nanometers and, as in the case of the Shewanella oneidensis Mtr electron conduit, traverse the bacterial cell wall to extracellular electron acceptors such as solid ferrihydrite. Here, the biochemical strategies of protein-based electron transfer are presented in order to provide a basis for future studies on the basis of which a more comprehensive understanding of the structural biology of enzymatic electrosynthesis may be attained.
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25
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Bacteria coated cathodes as an in-situ hydrogen evolving platform for microbial electrosynthesis. Sci Rep 2020; 10:19852. [PMID: 33199799 PMCID: PMC7670457 DOI: 10.1038/s41598-020-76694-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 11/02/2020] [Indexed: 11/13/2022] Open
Abstract
Hydrogen is a key intermediate element in microbial electrosynthesis as a mediator of the reduction of carbon dioxide (CO2) into added value compounds. In the present work we aimed at studying the biological production of hydrogen in biocathodes operated at − 1.0 V vs. Ag/AgCl, using a highly comparable technology and CO2 as carbon feedstock. Ten bacterial strains were chosen from genera Rhodobacter, Rhodopseudomonas, Rhodocyclus, Desulfovibrio and Sporomusa, all described as hydrogen producing candidates. Monospecific biofilms were formed on carbon cloth cathodes and hydrogen evolution was constantly monitored using a microsensor. Eight over ten bacteria strains showed electroactivity and H2 production rates increased significantly (two to eightfold) compared to abiotic conditions for two of them (Desulfovibrio paquesii and Desulfovibrio desulfuricans). D. paquesii DSM 16681 exhibited the highest production rate (45.6 ± 18.8 µM min−1) compared to abiotic conditions (5.5 ± 0.6 µM min−1), although specific production rates (per 16S rRNA copy) were similar to those obtained for other strains. This study demonstrated that many microorganisms are suspected to participate in net hydrogen production but inherent differences among strains do occur, which are relevant for future developments of resilient biofilm coated cathodes as a stable hydrogen production platform in microbial electrosynthesis.
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26
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Berger S, Cabrera-Orefice A, Jetten MSM, Brandt U, Welte CU. Investigation of central energy metabolism-related protein complexes of ANME-2d methanotrophic archaea by complexome profiling. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148308. [PMID: 33002447 DOI: 10.1016/j.bbabio.2020.148308] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 09/07/2020] [Accepted: 09/09/2020] [Indexed: 02/02/2023]
Abstract
The anaerobic oxidation of methane is important for mitigating emissions of this potent greenhouse gas to the atmosphere and is mediated by anaerobic methanotrophic archaea. In a 'Candidatus Methanoperedens BLZ2' enrichment culture used in this study, methane is oxidized to CO2 with nitrate being the terminal electron acceptor of an anaerobic respiratory chain. Energy conservation mechanisms of anaerobic methanotrophs have mostly been studied at metagenomic level and hardly any protein data is available at this point. To close this gap, we used complexome profiling to investigate the presence and subunit composition of protein complexes involved in energy conservation processes. All enzyme complexes and their subunit composition involved in reverse methanogenesis were identified. The membrane-bound enzymes of the respiratory chain, such as F420H2:quinone oxidoreductase, membrane-bound heterodisulfide reductase, nitrate reductases and Rieske cytochrome bc1 complex were all detected. Additional or putative subunits such as an octaheme subunit as part of the Rieske cytochrome bc1 complex were discovered that will be interesting targets for future studies. Furthermore, several soluble proteins were identified, which are potentially involved in oxidation of reduced ferredoxin produced during reverse methanogenesis leading to formation of small organic molecules. Taken together these findings provide an updated, refined picture of the energy metabolism of the environmentally important group of anaerobic methanotrophic archaea.
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Affiliation(s)
- Stefanie Berger
- Institute for Wetland and Water Research, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands.
| | - Alfredo Cabrera-Orefice
- Molecular Bioenergetics Group, Radboud Institute for Molecular Life Sciences, Department of Pediatrics, Radboud University Medical Center, Geert-Grooteplein Zuid 10, 6525 GA Nijmegen, the Netherlands
| | - Mike S M Jetten
- Institute for Wetland and Water Research, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands.
| | - Ulrich Brandt
- Molecular Bioenergetics Group, Radboud Institute for Molecular Life Sciences, Department of Pediatrics, Radboud University Medical Center, Geert-Grooteplein Zuid 10, 6525 GA Nijmegen, the Netherlands.
| | - Cornelia U Welte
- Institute for Wetland and Water Research, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands.
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27
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Ruth JC, Milton RD, Gu W, Spormann AM. Enhanced Electrosynthetic Hydrogen Evolution by Hydrogenases Embedded in a Redox-Active Hydrogel. Chemistry 2020; 26:7323-7329. [PMID: 32074397 DOI: 10.1002/chem.202000750] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Indexed: 01/27/2023]
Abstract
Molecular hydrogen is a major high-energy carrier for future energy technologies, if produced from renewable electrical energy. Hydrogenase enzymes offer a pathway for bioelectrochemically producing hydrogen that is advantageous over traditional platforms for hydrogen production because of low overpotentials and ambient operating temperature and pressure. However, electron delivery from the electrode surface to the enzyme's active site is often rate-limiting. Here, it is shown that three different hydrogenases from Clostridium pasteurianum and Methanococcus maripaludis, when immobilized at a cathode in a cobaltocene-functionalized polyallylamine (Cc-PAA) redox polymer, mediate rapid and efficient hydrogen evolution. Furthermore, it is shown that Cc-PAA-mediated hydrogenases can operate at high faradaic efficiency (80-100 %) and low apparent overpotential (-0.578 to -0.593 V vs. SHE). Specific activities of these hydrogenases in the electrosynthetic Cc-PAA assay were comparable to their respective activities in traditional methyl viologen assays, indicating that Cc-PAA mediates electron transfer at high rates, to most of the embedded enzymes.
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Affiliation(s)
- John C Ruth
- Department of Chemical Engineering, E250 James. H. Clark Center, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA
| | - Ross D Milton
- Department of Civil and Environmental Engineering, E250 James. H. Clark Center, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA.,Current address: Department of Inorganic and Analytical Chemistry, University of Geneva, Sciences II, Quai Ernest-Ansermet 30, 1211, Geneva 4, Switzerland
| | - Wenyu Gu
- Department of Civil and Environmental Engineering, E250 James. H. Clark Center, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA
| | - Alfred M Spormann
- Department of Chemical Engineering, E250 James. H. Clark Center, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA.,Department of Civil and Environmental Engineering, E250 James. H. Clark Center, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA
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Yee MO, Deutzmann J, Spormann A, Rotaru AE. Cultivating electroactive microbes-from field to bench. NANOTECHNOLOGY 2020; 31:174003. [PMID: 31931483 DOI: 10.1088/1361-6528/ab6ab5] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Electromicrobiology is an emerging field investigating and exploiting the interaction of microorganisms with insoluble electron donors or acceptors. Some of the most recently categorized electroactive microorganisms became of interest to sustainable bioengineering practices. However, laboratories worldwide typically maintain electroactive microorganisms on soluble substrates, which often leads to a decrease or loss of the ability to effectively exchange electrons with solid electrode surfaces. In order to develop future sustainable technologies, we cannot rely solely on existing lab-isolates. Therefore, we must develop isolation strategies for environmental strains with electroactive properties superior to strains in culture collections. In this article, we provide an overview of the studies that isolated or enriched electroactive microorganisms from the environment using an anode as the sole electron acceptor (electricity-generating microorganisms) or a cathode as the sole electron donor (electricity-consuming microorganisms). Next, we recommend a selective strategy for the isolation of electroactive microorganisms. Furthermore, we provide a practical guide for setting up electrochemical reactors and highlight crucial electrochemical techniques to determine electroactivity and the mode of electron transfer in novel organisms.
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Affiliation(s)
- Mon Oo Yee
- Nordcee, Department of Biology, University of Southern Denmark, Odense, DK-5230, Denmark
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29
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Affiliation(s)
- Cécile Cadoux
- University of GenevaSciences II Quai Ernest-Ansermet 30 1211 Geneva 4 Switzerland
| | - Ross D. Milton
- University of GenevaSciences II Quai Ernest-Ansermet 30 1211 Geneva 4 Switzerland
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30
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An BA, Kleinbub S, Ozcan O, Koerdt A. Iron to Gas: Versatile Multiport Flow-Column Revealed Extremely High Corrosion Potential by Methanogen-Induced Microbiologically Influenced Corrosion (Mi-MIC). Front Microbiol 2020; 11:527. [PMID: 32296410 PMCID: PMC7136402 DOI: 10.3389/fmicb.2020.00527] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/11/2020] [Indexed: 01/01/2023] Open
Abstract
Currently, sulfate-reducing bacteria (SRB) is regarded as the main culprit of microbiologically influenced corrosion (MIC), mainly due to the low reported corrosion rates of other microorganisms. For example, the highest reported corrosion rate for methanogens is 0.065 mm/yr. However, by investigating methanogen-induced microbiologically influenced corrosion (Mi-MIC) using an in-house developed versatile multiport flow test column, extremely high corrosion rates were observed. We analyzed a large set of carbon steel beads, which were sectionally embedded into the test columns as substrates for iron-utilizing methanogen Methanobacterium IM1. After 14 days of operation using glass beads as fillers for section separation, the highest average corrosion rate of Methanobacterium IM1 was 0.2 mm/yr, which doubled that of Desulfovibrio ferrophilus IS5 and Desulfovibrio alaskensis 16109 investigated at the same conditions. At the most corroded region, nearly 80% of the beads lost 1% of their initial weight (fast-corrosion), resulting in an average corrosion rate of 0.2 mm/yr for Methanobacterium IM1-treated columns. When sand was used as filler material to mimic sediment conditions, average corrosion rates for Methanobacterium IM1 increased to 0.3 mm/yr (maximum 0.52 mm/yr) with over 83% of the beads having corrosion rates above 0.3 mm/yr. Scanning electron images of metal coupons extracted from the column showed methanogenic cells were clustered close to the metal surface. Methanobacterium IM1 is a hydrogenotrophic methanogen with higher affinity to metal than H2. Unlike SRB, Methanobacterium IM1 is not restricted to the availability of sulfate concentration in the environment. Thus, the use of the multiport flow column provided a new insight on the corrosion potential of methanogens, particularly in dynamic conditions, that offers new opportunities for monitoring and development of mitigation strategies. Overall, this study shows (1) under certain conditions methanogenic archaea can cause higher corrosion than SRB, (2) specific quantifications, i.e., maximum, average, and minimum corrosion rates can be determined, and (3) that spatial statistical evaluations of MIC can be carried out.
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Affiliation(s)
| | | | | | - Andrea Koerdt
- Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany
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31
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Philips J. Extracellular Electron Uptake by Acetogenic Bacteria: Does H 2 Consumption Favor the H 2 Evolution Reaction on a Cathode or Metallic Iron? Front Microbiol 2020; 10:2997. [PMID: 31998274 PMCID: PMC6966493 DOI: 10.3389/fmicb.2019.02997] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 12/11/2019] [Indexed: 12/30/2022] Open
Abstract
Some acetogenic bacteria are capable of using solid electron donors, such as a cathode or metallic iron [Fe(0)]. Acetogens using a cathode as electron donor are of interest for novel applications such as microbial electrosynthesis, while microorganisms using Fe(0) as electron donor cause detrimental microbial induced corrosion. The capacity to use solid electron donors strongly differs between acetogenic strains, which likely relates to their extracellular electron transfer (EET) mechanism. Different EET mechanisms have been proposed for acetogenic bacteria, including a direct mechanism and a H2 dependent indirect mechanism combined with extracellular hydrogenases catalyzing the H2 evolution reaction on the cathode or Fe(0) surface. Interestingly, low H2 partial pressures often prevail during acetogenesis with solid electron donors. Hence, an additional mechanism is here proposed: the maintenance of low H2 partial pressures by microbial H2 consumption, which thermodynamically favors the H2 evolution reaction on the cathode or Fe(0) surface. This work elaborates how the H2 partial pressure affects the H2 evolution onset potential and the H2 evolution rate on a cathode, as well as the free energy change of the anoxic corrosion reaction. In addition, the H2 consumption characteristics, i.e., H2 threshold (thermodynamic limit for H2 consumption) and H2 consumption kinetic parameters, of acetogenic bacteria are reviewed and evidence is discussed for strongly different H2 consumption characteristics. Different acetogenic strains are thus expected to maintain different H2 partial pressures on a cathode or Fe(0) surface, while those that maintain lower H2 partial pressures (lower H2 threshold, higher H2 affinity) more strongly increase the H2 evolution reaction. Consequently, I hypothesize that the different capacities of acetogenic bacteria to use solid electron donors are related to differences in their H2 consumption characteristics. The focus of this work is on acetogenic bacteria, but similar considerations are likely also relevant for other hydrogenotrophic microorganisms.
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Affiliation(s)
- Jo Philips
- Department of Engineering, Aarhus University, Aarhus, Denmark
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32
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Liu C, Sun D, Zhao Z, Dang Y, Holmes DE. Methanothrix enhances biogas upgrading in microbial electrolysis cell via direct electron transfer. BIORESOURCE TECHNOLOGY 2019; 291:121877. [PMID: 31376672 DOI: 10.1016/j.biortech.2019.121877] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/20/2019] [Accepted: 07/22/2019] [Indexed: 06/10/2023]
Abstract
Bioelectrochemical conversion of CO2 to CH4 is a promising way to increase the calorific value of biogas produced during anaerobic digestion. There are two groups of methanogens enriched in these systems, hydrogenotrophs and acetoclastic methanogens that can also directly accept electrons from an electrode or another microorganism. In this study, a microbial electrolysis cell (MEC) poised at -500 mV (vs. SHE) was operated for biogas upgrading. Methane content in the biogas increased from 71% to >90%, and 8.2% of the CO2 was converted to methane. Methanothrix, an acetoclastic methanogen that can participate in direct electron transfer (DET), and Azonexus, an acetate-oxidizing electrogen, were enriched on the cathode. Transcriptomics revealed that Methanothrix on the cathode were using the CO2 reduction pathway, while Methanothrix in the bulk sludge were using the acetate decarboxylation pathway for production of methane. These results show that stimulation of DET in MEC enhances biogas-upgrading processes.
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Affiliation(s)
- Chuanqi 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
| | - 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
| | - 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
| | - 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.
| | - Dawn E Holmes
- Department of Physical and Biological Sciences, Western New England University, 1215 Wilbraham Rd, Springfield, MA 01119, United States
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Classification and enzyme kinetics of formate dehydrogenases for biomanufacturing via CO2 utilization. Biotechnol Adv 2019; 37:107408. [DOI: 10.1016/j.biotechadv.2019.06.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/26/2019] [Accepted: 06/10/2019] [Indexed: 12/14/2022]
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Mayer F, Enzmann F, Lopez AM, Holtmann D. Performance of different methanogenic species for the microbial electrosynthesis of methane from carbon dioxide. BIORESOURCE TECHNOLOGY 2019; 289:121706. [PMID: 31279320 DOI: 10.1016/j.biortech.2019.121706] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/21/2019] [Accepted: 06/26/2019] [Indexed: 06/09/2023]
Abstract
Microbial electrosynthesis (MES) is a promising technology to convert CO2 and electricity into the biofuel methane using methanogens. Until now, most investigations on electro-methanogenesis are "proof-of-principle" studies. In this paper, different strains were quantitatively compared in regard to final methane concentration, yields based on CO2-conversion, productivities as well as Coulombic efficiencies in order to identify suitable organisms for MES. Methanococcus vannielii, Methanococcus maripaludis, Methanolacinia petrolearia, Methanobacterium congolense, and Methanoculleus submarinus were able to produce methane via MES at -700 mV vs. standard hydrogen electrode (SHE). Beside methane also biological H2 production was detected during MES, which might be due to the involvement of hydrogenases. A direct electron transfer pathway is most likely. Obviously, M. maripaludis is the most resource efficient methane producer in microbial electrosynthesis regarding the methane productivity (8.81 ± 0.51 mmol m-2 d-1) and the Coulombic efficiency (58.9 ± 0.8%).
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Affiliation(s)
- Florian Mayer
- DECHEMA-Forschungsinstitut, Industrielle Biotechnologie, Frankfurt am Main, Germany
| | - Franziska Enzmann
- DECHEMA-Forschungsinstitut, Industrielle Biotechnologie, Frankfurt am Main, Germany
| | | | - Dirk Holtmann
- DECHEMA-Forschungsinstitut, Industrielle Biotechnologie, Frankfurt am Main, Germany.
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35
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Baltic Sea methanogens compete with acetogens for electrons from metallic iron. ISME JOURNAL 2019; 13:3011-3023. [PMID: 31444483 PMCID: PMC6864099 DOI: 10.1038/s41396-019-0490-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 07/17/2019] [Accepted: 08/02/2019] [Indexed: 01/05/2023]
Abstract
Microbially induced corrosion of metallic iron (Fe0)-containing structures is an environmental and economic hazard. Methanogens are abundant in low-sulfide environments and yet their specific role in Fe0 corrosion is poorly understood. In this study, Sporomusa and Methanosarcina dominated enrichments from Baltic Sea methanogenic sediments that were established with Fe0 as the sole electron donor and CO2 as the electron acceptor. The Baltic-Sporomusa was phylogenetically affiliated to the electroactive acetogen S. silvacetica. Baltic-Sporomusa adjusted rapidly to growth on H2. On Fe0, spent filtrate enhanced growth of this acetogen suggesting that it was using endogenous enzymes to retrieve electrons and produce acetate. Previous studies have proposed that acetate produced by acetogens can feed commensal acetoclastic methanogens such as Methanosarcina. However, Baltic-methanogens could not generate methane from acetate, plus the decrease or absence of acetogens stimulated their growth. The decrease in numbers of Sporomusa was concurrent with an upsurge in Methanosarcina and increased methane production, suggesting that methanogens compete with acetogens for electrons from Fe0. Furthermore, Baltic-methanogens were unable to use H2 (1.5 atm) for methanogenesis and were inhibited by spent filtrate additions, indicating that enzymatically produced H2 is not a favorable electron donor. We hypothesize that Baltic-methanogens retrieve electrons from Fe0 via a yet enigmatic direct electron uptake mechanism.
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36
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Perona-Vico E, Blasco-Gómez R, Colprim J, Puig S, Bañeras L. [NiFe]-hydrogenases are constitutively expressed in an enriched Methanobacterium sp. population during electromethanogenesis. PLoS One 2019; 14:e0215029. [PMID: 30973887 PMCID: PMC6459506 DOI: 10.1371/journal.pone.0215029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 03/25/2019] [Indexed: 01/18/2023] Open
Abstract
Electromethanogenesis is the bioreduction of carbon dioxide (CO2) to methane (CH4) utilizing an electrode as electron donor. Some studies have reported the active participation of Methanobacterium sp. in electron capturing, although no conclusive results are available. In this study, we aimed at determining short-time changes in the expression levels of [NiFe]-hydrogenases (Eha, Ehb and Mvh), heterodisulfide reductase (Hdr), coenzyme F420-reducing [NiFe]-hydrogenase (Frh), and hydrogenase maturation protein (HypD), according to the electron flow in independently connected carbon cloth cathodes poised at– 800 mV vs. standard hydrogen electrode (SHE). Amplicon massive sequencing of cathode biofilm confirmed the presence of an enriched Methanobacterium sp. population (>70% of sequence reads), which remained in an active state (78% of cDNA reads), tagging this archaeon as the main methane producer in the system. Quantitative RT-PCR determinations of ehaB, ehbL, mvhA, hdrA, frhA, and hypD genes resulted in only slight (up to 1.5 fold) changes for four out of six genes analyzed when cells were exposed to open (disconnected) or closed (connected) electric circuit events. The presented results suggested that suspected mechanisms for electron capturing were not regulated at the transcriptional level in Methanobacterium sp. for short time exposures of the cells to connected-disconnected circuits. Additional tests are needed in order to confirm proteins that participate in electron capturing in Methanobacterium sp.
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Affiliation(s)
- Elisabet Perona-Vico
- Molecular Microbial Ecology Group, Institute of Aquatic Ecology, University of Girona, Girona, Spain
- * E-mail: (LB); (EPV)
| | | | - Jesús Colprim
- LEQUiA, Institute of the Environment, University of Girona, Girona, Spain
| | - Sebastià Puig
- LEQUiA, Institute of the Environment, University of Girona, Girona, Spain
| | - Lluis Bañeras
- Molecular Microbial Ecology Group, Institute of Aquatic Ecology, University of Girona, Girona, Spain
- * E-mail: (LB); (EPV)
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37
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El Abbadi SH, Criddle CS. Engineering the Dark Food Chain. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:2273-2287. [PMID: 30640466 DOI: 10.1021/acs.est.8b04038] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Meeting global food needs in the face of climate change and resource limitation requires innovative approaches to food production. Here, we explore incorporation of new dark food chains into human food systems, drawing inspiration from natural ecosystems, the history of single cell protein, and opportunities for new food production through wastewater treatment, microbial protein production, and aquaculture. The envisioned dark food chains rely upon chemoautotrophy in lieu of photosynthesis, with primary production based upon assimilation of CH4 and CO2 by methane- and hydrogen-oxidizing bacteria. The stoichiometry, kinetics, and thermodynamics of these bacteria are evaluated, and opportunities for recycling of carbon, nitrogen, and water are explored. Because these processes do not require light delivery, high volumetric productivities are possible; because they are exothermic, heat is available for downstream protein processing; because the feedstock gases are cheap, existing pipeline infrastructure could facilitate low-cost energy-efficient delivery in urban environments. Potential life-cycle benefits include: a protein alternative to fishmeal; partial decoupling of animal feed from human food; climate change mitigation due to decreased land use for agriculture; efficient local cycling of carbon and nutrients that offsets the need for energy-intensive fertilizers; and production of high value products, such as the prebiotic polyhydroxybutyrate.
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Affiliation(s)
- Sahar H El Abbadi
- Department of Civil and Environmental Engineering , Stanford University , Stanford , California 94305-4020 , United States
| | - Craig S Criddle
- Department of Civil and Environmental Engineering , Stanford University , Stanford , California 94305-4020 , United States
- William and Cloy Codiga Resource Recovery Center , Stanford University , Stanford , California 94305-4020 , United States
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38
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Enzmann F, Mayer F, Stöckl M, Mangold KM, Hommel R, Holtmann D. Transferring bioelectrochemical processes from H-cells to a scalable bubble column reactor. Chem Eng Sci 2019. [DOI: 10.1016/j.ces.2018.08.056] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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39
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Methanogens: pushing the boundaries of biology. Emerg Top Life Sci 2018; 2:629-646. [PMID: 33525834 PMCID: PMC7289024 DOI: 10.1042/etls20180031] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 10/23/2018] [Accepted: 10/24/2018] [Indexed: 01/15/2023]
Abstract
Methanogens are anaerobic archaea that grow by producing methane gas. These microbes and their exotic metabolism have inspired decades of microbial physiology research that continues to push the boundary of what we know about how microbes conserve energy to grow. The study of methanogens has helped to elucidate the thermodynamic and bioenergetics basis of life, contributed our understanding of evolution and biodiversity, and has garnered an appreciation for the societal utility of studying trophic interactions between environmental microbes, as methanogens are important in microbial conversion of biogenic carbon into methane, a high-energy fuel. This review discusses the theoretical basis for energy conservation by methanogens and identifies gaps in methanogen biology that may be filled by undiscovered or yet-to-be engineered organisms.
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Philips J, Monballyu E, Georg S, De Paepe K, Prévoteau A, Rabaey K, Arends JBA. AnAcetobacteriumstrain isolated with metallic iron as electron donor enhances iron corrosion by a similar mechanism asSporomusa sphaeroides. FEMS Microbiol Ecol 2018; 95:5184449. [DOI: 10.1093/femsec/fiy222] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 11/14/2018] [Indexed: 02/02/2023] Open
Affiliation(s)
- Jo Philips
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Eva Monballyu
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Steffen Georg
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Kim De Paepe
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Antonin Prévoteau
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Korneel Rabaey
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Jan B A Arends
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, Ghent 9000, Belgium
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Tsurumaru H, Ito N, Mori K, Wakai S, Uchiyama T, Iino T, Hosoyama A, Ataku H, Nishijima K, Mise M, Shimizu A, Harada T, Horikawa H, Ichikawa N, Sekigawa T, Jinno K, Tanikawa S, Yamazaki J, Sasaki K, Yamazaki S, Fujita N, Harayama S. An extracellular [NiFe] hydrogenase mediating iron corrosion is encoded in a genetically unstable genomic island in Methanococcus maripaludis. Sci Rep 2018; 8:15149. [PMID: 30310166 PMCID: PMC6181927 DOI: 10.1038/s41598-018-33541-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 10/01/2018] [Indexed: 11/09/2022] Open
Abstract
Certain methanogens deteriorate steel surfaces through a process called microbiologically influenced corrosion (MIC). However, the mechanisms of MIC, whereby methanogens oxidize zerovalent iron (Fe0), are largely unknown. In this study, Fe0-corroding Methanococcus maripaludis strain OS7 and its derivative (strain OS7mut1) defective in Fe0-corroding activity were isolated. Genomic analysis of these strains demonstrated that the strain OS7mut1 contained a 12-kb chromosomal deletion. The deleted region, termed "MIC island", encoded the genes for the large and small subunits of a [NiFe] hydrogenase, the TatA/TatC genes necessary for the secretion of the [NiFe] hydrogenase, and a gene for the hydrogenase maturation protease. Thus, the [NiFe] hydrogenase may be secreted outside the cytoplasmic membrane, where the [NiFe] hydrogenase can make direct contact with Fe0, and oxidize it, generating hydrogen gas: Fe0 + 2 H+ → Fe2+ + H2. Comparative analysis of extracellular and intracellular proteomes of strain OS7 supported this hypothesis. The identification of the MIC genes enables the development of molecular tools to monitor epidemiology, and to perform surveillance and risk assessment of MIC-inducing M. maripaludis.
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Affiliation(s)
- Hirohito Tsurumaru
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Naofumi Ito
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Koji Mori
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Satoshi Wakai
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Taku Uchiyama
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Takao Iino
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Akira Hosoyama
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Hanako Ataku
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Keiko Nishijima
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Miyako Mise
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Ai Shimizu
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Takeshi Harada
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Hiroshi Horikawa
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Natsuko Ichikawa
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Tomohiro Sekigawa
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Koji Jinno
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Satoshi Tanikawa
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Jun Yamazaki
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Kazumi Sasaki
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Syuji Yamazaki
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Nobuyuki Fujita
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan
| | - Shigeaki Harayama
- NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), Chiba, 292-0818, Japan.
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Vyrides I, Andronikou M, Kyprianou A, Modic A, Filippeti A, Yiakoumis C, Samanides CG. CO2 conversion to CH4 using Zero Valent Iron (ZVI) and anaerobic granular sludge: Optimum batch conditions and microbial pathways. J CO2 UTIL 2018. [DOI: 10.1016/j.jcou.2018.08.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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A Novel Shewanella Isolate Enhances Corrosion by Using Metallic Iron as the Electron Donor with Fumarate as the Electron Acceptor. Appl Environ Microbiol 2018; 84:AEM.01154-18. [PMID: 30054363 DOI: 10.1128/aem.01154-18] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 07/21/2018] [Indexed: 11/20/2022] Open
Abstract
The involvement of Shewanella spp. in biocorrosion is often attributed to their Fe(III)-reducing properties, but they could also affect corrosion by using metallic iron as an electron donor. Previously, we isolated Shewanella strain 4t3-1-2LB from an acetogenic community enriched with Fe(0) as the sole electron donor. Here, we investigated its use of Fe(0) as an electron donor with fumarate as an electron acceptor and explored its corrosion-enhancing mechanism. Without Fe(0), strain 4t3-1-2LB fermented fumarate to succinate and CO2, as was shown by the reaction stoichiometry and pH. With Fe(0), strain 4t3-1-2LB completely reduced fumarate to succinate and increased the Fe(0) corrosion rate (7.0 ± 0.6)-fold in comparison to that of abiotic controls (based on the succinate-versus-abiotic hydrogen formation rate). Fumarate reduction by strain 4t3-1-2LB was, at least in part, supported by chemical hydrogen formation on Fe(0). Filter-sterilized spent medium increased the hydrogen generation rate only 1.5-fold, and thus extracellular hydrogenase enzymes appear to be insufficient to explain the enhanced corrosion rate. Electrochemical measurements suggested that strain 4t3-1-2LB did not excrete dissolved redox mediators. Exchanging the medium and scanning electron microscopy (SEM) imaging indicated that cells were attached to Fe(0). It is possible that strain 4t3-1-2LB used a direct mechanism to withdraw electrons from Fe(0) or favored chemical hydrogen formation on Fe(0) through maintaining low hydrogen concentrations. In coculture with an Acetobacterium strain, strain 4t3-1-2LB did not enhance acetogenesis from Fe(0). This work describes a strong corrosion enhancement by a Shewanella strain through its use of Fe(0) as an electron donor and provides insights into its corrosion-enhancing mechanism.IMPORTANCE Shewanella spp. are frequently found on corroded metal structures. Their role in microbial influenced corrosion has been attributed mainly to their Fe(III)-reducing properties and, therefore, has been studied with the addition of an electron donor (lactate). Shewanella spp., however, can also use solid electron donors, such as cathodes and potentially Fe(0). In this work, we show that the electron acceptor fumarate supported the use of Fe(0) as the electron donor by Shewanella strain 4t3-1-2LB, which caused a (7.0 ± 0.6)-fold increase of the corrosion rate. The corrosion-enhancing mechanism likely involved cell surface-associated components in direct contact with the Fe(0) surface or maintenance of low hydrogen levels by attached cells, thereby favoring chemical hydrogen formation by Fe(0). This work sheds new light on the role of Shewanella spp. in biocorrosion, while the insights into the corrosion-enhancing mechanism contribute to the understanding of extracellular electron uptake processes.
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Milton RD, Ruth JC, Deutzmann JS, Spormann AM. Methanococcus maripaludis Employs Three Functional Heterodisulfide Reductase Complexes for Flavin-Based Electron Bifurcation Using Hydrogen and Formate. Biochemistry 2018; 57:4848-4857. [DOI: 10.1021/acs.biochem.8b00662] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ross D. Milton
- Departments of Chemical Engineering and Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - John C. Ruth
- Departments of Chemical Engineering and Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Jörg S. Deutzmann
- Departments of Chemical Engineering and Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Alfred M. Spormann
- Departments of Chemical Engineering and Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
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Yuan M, Sahin S, Cai R, Abdellaoui S, Hickey DP, Minteer SD, Milton RD. Creating a Low‐Potential Redox Polymer for Efficient Electroenzymatic CO
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Reduction. Angew Chem Int Ed Engl 2018; 57:6582-6586. [DOI: 10.1002/anie.201803397] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/04/2018] [Indexed: 01/27/2023]
Affiliation(s)
- Mengwei Yuan
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Selmihan Sahin
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
- Department of ChemistryFaculty of Arts and SciencesSuleyman Demirel University, Cunur Isparta 32260 Turkey
| | - Rong Cai
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Sofiene Abdellaoui
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - David P. Hickey
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Shelley D. Minteer
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Ross D. Milton
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
- Current address: Department of Civil & Environmental EngineeringStanford University, E-250 James H. Clark Center 318 Campus Drive Stanford CA 94305 USA
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Yuan M, Sahin S, Cai R, Abdellaoui S, Hickey DP, Minteer SD, Milton RD. Creating a Low‐Potential Redox Polymer for Efficient Electroenzymatic CO
2
Reduction. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201803397] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Mengwei Yuan
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Selmihan Sahin
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
- Department of ChemistryFaculty of Arts and SciencesSuleyman Demirel University, Cunur Isparta 32260 Turkey
| | - Rong Cai
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Sofiene Abdellaoui
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - David P. Hickey
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Shelley D. Minteer
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
| | - Ross D. Milton
- Department of ChemistryUniversity of Utah 315 S 1400 E Salt Lake City UT 84112 USA
- Current address: Department of Civil & Environmental EngineeringStanford University, E-250 James H. Clark Center 318 Campus Drive Stanford CA 94305 USA
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