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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Ma Y, Qu Y, Yao X, Xia C, Lv M, Lin X, Zhang L, Zhang M, Hu B. Unveiling the unique role of iron in the metabolism of methanogens: A review. ENVIRONMENTAL RESEARCH 2024; 250:118495. [PMID: 38367837 DOI: 10.1016/j.envres.2024.118495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/06/2024] [Accepted: 02/13/2024] [Indexed: 02/19/2024]
Abstract
Methanogens are the main participants in the carbon cycle, catalyzing five methanogenic pathways. Methanogens utilize different iron-containing functional enzymes in different methanogenic processes. Iron is a vital element in methanogens, which can serve as a carrier or reactant in electron transfer. Therefore, iron plays an important role in the growth and metabolism of methanogens. In this paper, we cast light on the types and functions of iron-containing functional enzymes involved in different methanogenic pathways, and the roles iron play in energy/substance metabolism of methanogenesis. Furthermore, this review provides certain guiding significance for lowering CH4 emissions, boosting the carbon sink capacity of ecosystems and promoting green and low-carbon development in the future.
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Affiliation(s)
- Yuxin Ma
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China; Department of Environmental Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ying Qu
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiangwu Yao
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, Zhejiang, China; Department of Environmental Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chujun Xia
- Department of Environmental Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Mengjie Lv
- Department of Environmental Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiao Lin
- Department of Environmental Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Lili Zhang
- Beijing Enterprises Water Group Limited, Beijing, China
| | - Meng Zhang
- Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, Zhejiang, China; Department of Environmental Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Baolan Hu
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, Zhejiang, China; Department of Environmental Engineering, Zhejiang University, Hangzhou, Zhejiang, China.
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3
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Wang D, Ueki T, Ma P, Xu D, Lovley DR. Elucidating microbial iron corrosion mechanisms with a hydrogenase-deficient strain of Desulfovibrio vulgaris. MLIFE 2024; 3:269-276. [PMID: 38948142 PMCID: PMC11211667 DOI: 10.1002/mlf2.12133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/14/2024] [Accepted: 04/29/2024] [Indexed: 07/02/2024]
Abstract
Sulfate-reducing microorganisms extensively contribute to the corrosion of ferrous metal infrastructure. There is substantial debate over their corrosion mechanisms. We investigated Fe0 corrosion with Desulfovibrio vulgaris, the sulfate reducer most often employed in corrosion studies. Cultures were grown with both lactate and Fe0 as potential electron donors to replicate the common environmental condition in which organic substrates help fuel the growth of corrosive microbes. Fe0 was corroded in cultures of a D. vulgaris hydrogenase-deficient mutant with the 1:1 correspondence between Fe0 loss and H2 accumulation expected for Fe0 oxidation coupled to H+ reduction to H2. This result and the extent of sulfate reduction indicated that D. vulgaris was not capable of direct Fe0-to-microbe electron transfer even though it was provided with a supplementary energy source in the presence of abundant ferrous sulfide. Corrosion in the hydrogenase-deficient mutant cultures was greater than in sterile controls, demonstrating that H2 removal was not necessary for the enhanced corrosion observed in the presence of microbes. The parental H2-consuming strain corroded more Fe0 than the mutant strain, which could be attributed to H2 oxidation coupled to sulfate reduction, producing sulfide that further stimulated Fe0 oxidation. The results suggest that H2 consumption is not necessary for microbially enhanced corrosion, but H2 oxidation can indirectly promote corrosion by increasing sulfide generation from sulfate reduction. The finding that D. vulgaris was incapable of direct electron uptake from Fe0 reaffirms that direct metal-to-microbe electron transfer has yet to be rigorously described in sulfate-reducing microbes.
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Affiliation(s)
- Di Wang
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyangChina
| | - Toshiyuki Ueki
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyangChina
| | - Peiyu Ma
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyangChina
| | - Dake Xu
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyangChina
| | - Derek R. Lovley
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Department of MicrobiologyUniversity of MassachusettsAmherstMAUSA
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4
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Mei N, Tremblay PL, Wu Y, Zhang T. Proposed mechanisms of electron uptake in metal-corroding methanogens and their potential for CO 2 bioconversion applications. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171384. [PMID: 38432383 DOI: 10.1016/j.scitotenv.2024.171384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/28/2024] [Accepted: 02/28/2024] [Indexed: 03/05/2024]
Abstract
Some methanogens are electrotrophic bio-corroding microbes that can acquire electrons from solid surfaces including metals. In the laboratory, pure cultures of methanogenic cells oxidize iron-based materials including carbon steel, stainless steel, and Fe0. For buried or immersed pipelines or other metallic structures, methanogens are often major components of corroding biofilms with complex interspecies relationships. Models explaining how these microbes acquire electrons from solid donors are multifaceted and include electron transfer via redox mediators such as H2 or by direct contact through membrane proteins. Understanding the electron uptake (EU) routes employed by corroding methanogens is essential to develop efficient strategies for corrosion prevention. It is also beneficial for the development of bioenergy applications relying on methanogenic EU from solid donors such as bioelectromethanogenesis, hybrid photosynthesis, and the acceleration of anaerobic digestion with electroconductive particles. Many methanogenic species carrying out biocorrosion are the same ones forming the extensive abiotic-biological interfaces at the core of these bio-applications. This review will discuss the interactions between corrosive methanogens and metals and how the EU capability of these microbes can be harnessed for different sustainable biotechnologies.
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Affiliation(s)
- Nan Mei
- Institut WUT-AMU, Wuhan University of Technology, Wuhan 430070, PR China
| | - Pier-Luc Tremblay
- Institut WUT-AMU, Wuhan University of Technology, Wuhan 430070, PR China; School of Chemistry, Chemical Engineering, and Life Science, Wuhan University of Technology, Wuhan 430070, PR China; Shaoxing Institute for Advanced Research, Wuhan University of Technology, Shaoxing 312300, PR China; Sanya Science and Education Innovation Park, Wuhan University of Technology, Sanya 572024, PR China
| | - Yuyang Wu
- Institut WUT-AMU, Wuhan University of Technology, Wuhan 430070, PR China
| | - Tian Zhang
- Institut WUT-AMU, Wuhan University of Technology, Wuhan 430070, PR China; School of Chemistry, Chemical Engineering, and Life Science, Wuhan University of Technology, Wuhan 430070, PR China; Shaoxing Institute for Advanced Research, Wuhan University of Technology, Shaoxing 312300, PR China; Sanya Science and Education Innovation Park, Wuhan University of Technology, Sanya 572024, PR China.
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5
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Gupta D, Chen K, Elliott SJ, Nayak DD. MmcA is an electron conduit that facilitates both intracellular and extracellular electron transport in Methanosarcina acetivorans. Nat Commun 2024; 15:3300. [PMID: 38632227 PMCID: PMC11024163 DOI: 10.1038/s41467-024-47564-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 04/05/2024] [Indexed: 04/19/2024] Open
Abstract
Methanogens are a diverse group of Archaea that obligately couple energy conservation to the production of methane. Some methanogens encode alternate pathways for energy conservation, like anaerobic respiration, but the biochemical details of this process are unknown. We show that a multiheme c-type cytochrome called MmcA from Methanosarcina acetivorans is important for intracellular electron transport during methanogenesis and can also reduce extracellular electron acceptors like soluble Fe3+ and anthraquinone-2,6-disulfonate. Consistent with these observations, MmcA displays reversible redox features ranging from -100 to -450 mV versus SHE. Additionally, mutants lacking mmcA have significantly slower Fe3+ reduction rates. The mmcA locus is prevalent in members of the Order Methanosarcinales and is a part of a distinct clade of multiheme cytochromes that are closely related to octaheme tetrathionate reductases. Taken together, MmcA might act as an electron conduit that can potentially support a variety of energy conservation strategies that extend beyond methanogenesis.
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Affiliation(s)
- Dinesh Gupta
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Keying Chen
- Department of Chemistry, Boston University, Boston, MA, USA
| | - Sean J Elliott
- Department of Chemistry, Boston University, Boston, MA, USA
| | - Dipti D Nayak
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
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6
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Li K, Ji L, Gao M, Liang Q, Lan H, Lu W, Zhang W, Zhang Y. Mechanisms of anaerobic treatment of sulfate-containing organic wastewater mediated by Fe 0 under different initial pH values. Bioprocess Biosyst Eng 2024; 47:417-427. [PMID: 38424249 DOI: 10.1007/s00449-024-02974-w] [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: 09/18/2023] [Accepted: 01/19/2024] [Indexed: 03/02/2024]
Abstract
The anaerobic treatment of sulfide-containing organic wastewater (SCOW) is significantly affected by pH, causing dramatic decrease of treatment efficiency when pH deviates from its appropriate range. Fe0 has proved as an effective strategy on mitigating the impact of pH. However, systematic analysis of the influence mechanism is still lacking. To fill this gap, the impact of different initial pH values on anaerobic treatment efficiency of SCOW with Fe0 addition, the change of fermentation type and methanogens, and intra-extracellular electron transfer were explored in this study. The results showed that Fe0 addition enhanced the efficacy of anaerobic treatment of SCOW at adjusted initial pH values, especially at pH 6. Mechanism analysis showed that respiratory chain-related enzymes and electron shuttle secretion and resistance reduction were stimulated by soluble iron ions generated by Fe0 at pH 6, which accelerated intra-extracellular electron transfer of microorganisms, and ultimately alleviated the impact of acidic pH on the system. While at pH 8, Fe0 addition increased the acetogenic bacteria abundance, as well as optimized the fermentation type and improved the F420 coenzyme activity, resulting in the enhancement of treatment efficiency in the anaerobic system and remission of the effect of alkaline pH on the system. At the neutral pH, Fe0 addition had both advantages as stimulating the secretion of respiratory chain and electron transfer-related enzymes at pH 6 and optimizing the fermentation type pH 8, and thus enhanced the treatment efficacy. This study provides important insights and scientific basis for the application of new SCOW treatment technologies.
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Affiliation(s)
- Ke Li
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Linyu Ji
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Meng Gao
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Qiaochu Liang
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Huixia Lan
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
- Yunnan Provincial Key Laboratory of Rural Energy Engineering, Kunming, 650500, China.
| | - Weiwei Lu
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
| | - Wudi Zhang
- Yunnan Provincial Key Laboratory of Rural Energy Engineering, Kunming, 650500, China
| | - Yang Zhang
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
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7
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Holmes DE, Woodard TL, Smith JA, Musat F, Lovley DR. Electrobiocorrosion by microbes without outer-surface cytochromes. MLIFE 2024; 3:110-118. [PMID: 38827509 PMCID: PMC11139208 DOI: 10.1002/mlf2.12111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/14/2023] [Accepted: 12/03/2023] [Indexed: 06/04/2024]
Abstract
Anaerobic microbial corrosion of iron-containing metals causes extensive economic damage. Some microbes are capable of direct metal-to-microbe electron transfer (electrobiocorrosion), but the prevalence of electrobiocorrosion among diverse methanogens and acetogens is poorly understood because of a lack of tools for their genetic manipulation. Previous studies have suggested that respiration with 316L stainless steel as the electron donor is indicative of electrobiocorrosion, because, unlike pure Fe0, 316L stainless steel does not abiotically generate H2 as an intermediary electron carrier. Here, we report that all of the methanogens (Methanosarcina vacuolata, Methanothrix soehngenii, and Methanobacterium strain IM1) and acetogens (Sporomusa ovata and Clostridium ljungdahlii) evaluated respired with pure Fe0 as the electron donor, but only M. vacuolata, Mx. soehngenii, and S. ovata were capable of stainless steel electrobiocorrosion. The electrobiocorrosive methanogens required acetate as an additional energy source in order to produce methane from stainless steel. Cocultures of S. ovata and Mx. soehngenii demonstrated how acetogens can provide acetate to methanogens during corrosion. Not only was Methanobacterium strain IM1 not capable of electrobiocorrosion, but it also did not accept electrons from Geobacter metallireducens, an effective electron-donating partner for direct interspecies electron transfer to all methanogens that can directly accept electrons from Fe0. The finding that M. vacuolata, Mx. soehngenii, and S. ovata are capable of electrobiocorrosion, despite a lack of the outer-surface c-type cytochromes previously found to be important in other electrobiocorrosive microbes, demonstrates that there are multiple microbial strategies for making electrical contact with Fe0.
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Affiliation(s)
- Dawn E. Holmes
- Department of MicrobiologyUniversity of Massachusetts AmherstAmherstMassachusettsUSA
- Department of Physical and Biological ScienceWestern New England UniversitySpringfieldMassachusettsUSA
| | - Trevor L. Woodard
- Department of MicrobiologyUniversity of Massachusetts AmherstAmherstMassachusettsUSA
| | - Jessica A. Smith
- Department of MicrobiologyUniversity of Massachusetts AmherstAmherstMassachusettsUSA
- Department of Biomolecular SciencesCentral Connecticut State UniversityNew BritainConnecticutUSA
| | - Florin Musat
- Department of Biology, Section for MicrobiologyAarhus UniversityAarhusDenmark
- Department of Molecular Biology and Biotechnology, Faculty of Biology and GeologyBabeş‐Bolyai UniversityCluj‐NapocaRomania
| | - Derek R. Lovley
- Department of MicrobiologyUniversity of Massachusetts AmherstAmherstMassachusettsUSA
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8
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Lovley DR, Holmes DE. Comment on "Humic acid-dependent respiratory growth of Methanosarcina acetivorans involves pyrroloquinoline quinone" by Yuanxu Song et al. THE ISME JOURNAL 2024; 18:wrae020. [PMID: 38366259 PMCID: PMC10945356 DOI: 10.1093/ismejo/wrae020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/08/2023] [Accepted: 01/29/2024] [Indexed: 02/18/2024]
Affiliation(s)
- Derek R Lovley
- Department of Microbiology, University of Massachusetts-Amherst, 639 North Pleasant Street, Amherst, MA 01003, United States
| | - Dawn E Holmes
- Department of Microbiology, University of Massachusetts-Amherst, 639 North Pleasant Street, Amherst, MA 01003, United States
- Department of Physical and Biological Science, Western New England University, 1215 Wilbraham Road, Springfield, MA 01119, United States
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9
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Wang D, Zhou E, Xu D, Lovley DR. Burning question: Are there sustainable strategies to prevent microbial metal corrosion? Microb Biotechnol 2023; 16:2026-2035. [PMID: 37796110 PMCID: PMC10616648 DOI: 10.1111/1751-7915.14347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 09/18/2023] [Indexed: 10/06/2023] Open
Abstract
The global economic burden of microbial corrosion of metals is enormous. Microbial corrosion of iron-containing metals is most extensive under anaerobic conditions. Microbes form biofilms on metal surfaces and can directly extract electrons derived from the oxidation of Fe0 to Fe2+ to support anaerobic respiration. H2 generated from abiotic Fe0 oxidation also serves as an electron donor for anaerobic respiratory microbes. Microbial metabolites accelerate this abiotic Fe0 oxidation. Traditional strategies for curbing microbial metal corrosion include cathodic protection, scrapping, a diversity of biocides, alloys that form protective layers or release toxic metal ions, and polymer coatings. However, these approaches are typically expensive and/or of limited applicability and not environmentally friendly. Biotechnology may provide more effective and sustainable solutions. Biocides produced with microbes can be less toxic to eukaryotes, expanding the environments for potential application. Microbially produced surfactants can diminish biofilm formation by corrosive microbes, as can quorum-sensing inhibitors. Amendments of phages or predatory bacteria have been successful in attacking corrosive microbes in laboratory studies. Poorly corrosive microbes can form biofilms and/or deposit extracellular polysaccharides and minerals that protect the metal surface from corrosive microbes and their metabolites. Nitrate amendments permit nitrate reducers to outcompete highly corrosive sulphate-reducing microbes, reducing corrosion. Investigation of all these more sustainable corrosion mitigation strategies is in its infancy. More study, especially under environmentally relevant conditions, including diverse microbial communities, is warranted.
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Affiliation(s)
- Di Wang
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyangChina
| | - Enze Zhou
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyangChina
| | - Dake Xu
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyangChina
| | - Derek R. Lovley
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education)Northeastern UniversityShenyangChina
- Department of MicrobiologyUniversity of MassachusettsAmherstMassachusettsUSA
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10
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Abstract
A wide diversity of microorganisms, typically growing as biofilms, has been implicated in corrosion, a multi-trillion dollar a year problem. Aerobic microorganisms establish conditions that promote metal corrosion, but most corrosion has been attributed to anaerobes. Microbially produced organic acids, sulfide and extracellular hydrogenases can accelerate metallic iron (Fe0) oxidation coupled to hydrogen (H2) production, as can respiratory anaerobes consuming H2 as an electron donor. Some bacteria and archaea directly accept electrons from Fe0 to support anaerobic respiration, often with c-type cytochromes as the apparent outer-surface electrical contact with the metal. Functional genetic studies are beginning to define corrosion mechanisms more rigorously. Omics studies are revealing which microorganisms are associated with corrosion, but new strategies for recovering corrosive microorganisms in culture are required to evaluate corrosive capabilities and mechanisms. Interdisciplinary studies of the interactions among microorganisms and between microorganisms and metals in corrosive biofilms show promise for developing new technologies to detect and prevent corrosion. In this Review, we explore the role of microorganisms in metal corrosion and discuss potential ways to mitigate it.
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Affiliation(s)
- Dake Xu
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, China
| | - Tingyue Gu
- Department of Chemical & Biomolecular Engineering, Ohio University, Athens, OH, USA.
- Department of Biological Sciences, Ohio University, Athens, OH, USA.
- Institute for Corrosion and Multiphase Technology, Ohio University, Athens, OH, USA.
- Institute for Sustainable Energy and the Environment, Ohio University, Athens, OH, USA.
| | - Derek R Lovley
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA
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11
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Yan Z, Du K, Yan Y, Huang R, Zhu F, Yuan X, Wang S, Ferry JG. Respiration-driven methanotrophic growth of diverse marine methanogens. Proc Natl Acad Sci U S A 2023; 120:e2303179120. [PMID: 37729205 PMCID: PMC10523532 DOI: 10.1073/pnas.2303179120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 08/04/2023] [Indexed: 09/22/2023] Open
Abstract
Anaerobic marine environments are the third largest producer of the greenhouse gas methane. The release to the atmosphere is prevented by anaerobic 'methanotrophic archaea (ANME) dependent on a symbiotic association with sulfate-reducing bacteria or direct reduction of metal oxides. Metagenomic analyses of ANME are consistent with a reverse methanogenesis pathway, although no wild-type isolates have been available for validation and biochemical investigation. Herein is reported the characterization of methanotrophic growth for the diverse marine methanogens Methanosarcina acetivorans C2A and Methanococcoides orientis sp. nov. Growth was dependent on reduction of either ferrihydrite or humic acids revealing a respiratory mode of energy conservation. Acetate and/or formate were end products. Reversal of the well-characterized methanogenic pathways is remarkably like the consensus pathways for uncultured ANME based on extensive metagenomic analyses.
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Affiliation(s)
- Zhen Yan
- Shandong Key Laboratory of Water pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao266237, China
- Suzhou Research Institute, Shandong University, Suzhou, Jiangsu215123, China
| | - Kaifeng Du
- Shandong Key Laboratory of Water pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao266237, China
| | - Yunfeng Yan
- Shandong Key Laboratory of Water pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao266237, China
| | - Rui Huang
- Shandong Key Laboratory of Water pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao266237, China
| | - Fanping Zhu
- Shandong Key Laboratory of Water pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao266237, China
| | - Xianzheng Yuan
- Shandong Key Laboratory of Water pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao266237, China
| | - Shuguang Wang
- Shandong Key Laboratory of Water pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao266237, China
| | - James G. Ferry
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA16801
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12
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Jin Y, Zhou E, Ueki T, Zhang D, Fan Y, Xu D, Wang F, Lovley DR. Accelerated Microbial Corrosion by Magnetite and Electrically Conductive Pili through Direct Fe 0 -to-Microbe Electron Transfer. Angew Chem Int Ed Engl 2023; 62:e202309005. [PMID: 37525962 DOI: 10.1002/anie.202309005] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 07/26/2023] [Accepted: 07/31/2023] [Indexed: 08/02/2023]
Abstract
Electrobiocorrosion, the process in which microbes extract electrons from metallic iron (Fe0 ) through direct Fe0 -microbe electrical connections, is thought to contribute to the costly corrosion of iron-containing metals that impacts many industries. However, electrobiocorrosion mechanisms are poorly understood. We report here that electrically conductive pili (e-pili) and the conductive mineral magnetite play an important role in the electron transfer between Fe0 and Geobacter sulfurreducens, the first microbe in which electrobiocorrosion has been rigorously documented. Genetic modification to express poorly conductive pili substantially diminished corrosive pitting and rates of Fe0 -to-microbe electron flux. Magnetite reduced resistance to electron transfer, increasing corrosion currents and intensifying pitting. Studies with mutants suggested that the magnetite promoted electron transfer in a manner similar to the outer-surface c-type cytochrome OmcS. These findings, and the fact that magnetite is a common product of iron corrosion, suggest a potential positive feedback loop of magnetite produced during corrosion further accelerating electrobiocorrosion. The interactions of e-pili, cytochromes, and magnetite demonstrate mechanistic complexities of electrobiocorrosion, but also provide insights into detecting and possibly mitigating this economically damaging process.
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Affiliation(s)
- Yuting Jin
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, 110819, Shenyang, China
| | - Enze Zhou
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, 110819, Shenyang, China
| | - Toshiyuki Ueki
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, 110819, Shenyang, China
| | - Danni Zhang
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, 110819, Shenyang, China
| | - Yongqiang Fan
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, 110819, Shenyang, China
| | - Dake Xu
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, 110819, Shenyang, China
| | - Fuhui Wang
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
| | - Derek R Lovley
- Electrobiomaterials Institute, Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education), Northeastern University, 110819, Shenyang, China
- Shenyang National Laboratory for Materials Science, Northeastern University, 110819, Shenyang, China
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Gupta D, Chen K, Elliott SJ, Nayak DD. MmcA is an electron conduit that facilitates both intracellular and extracellular electron transport in Methanosarcina acetivorans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.20.537704. [PMID: 37131651 PMCID: PMC10153276 DOI: 10.1101/2023.04.20.537704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Methanogens are a diverse group of Archaea that couple energy conservation to the production of methane gas. While most methanogens have no alternate mode of energy conservation, strains like Methanosarcina acetivorans are known to also conserve energy by dissimilatory metal reduction (DSMR) in the presence of soluble ferric iron or iron-containing minerals. The ecological ramifications of energy conservation decoupled from methane production in methanogens are substantial, yet the molecular details are poorly understood. In this work, we conducted in vitro and in vivo studies with a multiheme c-type cytochrome (MHC), called MmcA, to establish its role during methanogenesis and DSMR in M. acetivorans. MmcA purified from M. acetivorans can donate electrons to methanophenazine, a membrane-bound electron carrier, to facilitate methanogenesis. In addition, MmcA can also reduce Fe(III) and the humic acid analog anthraquinone-2,6-disulfonate (AQDS) during DSMR. Furthermore, mutants lacking mmcA have slower Fe(III) reduction rates. The redox reactivities of MmcA are consistent with the electrochemical data where MmcA displays reversible redox features ranging from -100 to -450 mV versus SHE. MmcA is prevalent in members of the Order Methanosarcinales but does not belong to a known family of MHCs linked to extracellular electron transfer, bioinformatically, and instead forms a distinct clade that is closely related to octaheme tetrathionate reductases. Taken together, this study shows that MmcA is widespread in methanogens with cytochromes where it acts as an electron conduit to support a variety of energy conservation strategies that extend beyond methanogenesis.
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Affiliation(s)
- Dinesh Gupta
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Keying Chen
- Department of Chemistry, Boston University, Boston, MA, USA
| | | | - Dipti D. Nayak
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
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14
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H 2 Is a Major Intermediate in Desulfovibrio vulgaris Corrosion of Iron. mBio 2023; 14:e0007623. [PMID: 36786581 PMCID: PMC10127678 DOI: 10.1128/mbio.00076-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Desulfovibrio vulgaris has been a primary pure culture sulfate reducer for developing microbial corrosion concepts. Multiple mechanisms for how it accepts electrons from Fe0 have been proposed. We investigated Fe0 oxidation with a mutant of D. vulgaris in which hydrogenase genes were deleted. The hydrogenase mutant grew as well as the parental strain with lactate as the electron donor, but unlike the parental strain, it was not able to grow on H2. The parental strain reduced sulfate with Fe0 as the sole electron donor, but the hydrogenase mutant did not. H2 accumulated over time in Fe0 cultures of the hydrogenase mutant and sterile controls but not in parental strain cultures. Sulfide stimulated H2 production in uninoculated controls apparently by both reacting with Fe0 to generate H2 and facilitating electron transfer from Fe0 to H+. Parental strain supernatants did not accelerate H2 production from Fe0, ruling out a role for extracellular hydrogenases. Previously proposed electron transfer between Fe0 and D. vulgaris via soluble electron shuttles was not evident. The hydrogenase mutant did not reduce sulfate in the presence of Fe0 and either riboflavin or anthraquinone-2,6-disulfonate, and these potential electron shuttles did not stimulate parental strain sulfate reduction with Fe0 as the electron donor. The results demonstrate that D. vulgaris primarily accepts electrons from Fe0 via H2 as an intermediary electron carrier. These findings clarify the interpretation of previous D. vulgaris corrosion studies and suggest that H2-mediated electron transfer is an important mechanism for iron corrosion under sulfate-reducing conditions. IMPORTANCE Microbial corrosion of iron in the presence of sulfate-reducing microorganisms is economically significant. There is substantial debate over how microbes accelerate iron corrosion. Tools for genetic manipulation have only been developed for a few Fe(III)-reducing and methanogenic microorganisms known to corrode iron and in each case those microbes were found to accept electrons from Fe0 via direct electron transfer. However, iron corrosion is often most intense in the presence of sulfate-reducing microbes. The finding that Desulfovibrio vulgaris relies on H2 to shuttle electrons between Fe0 and cells revives the concept, developed in some of the earliest studies on microbial corrosion, that sulfate reducers consumption of H2 is a major microbial corrosion mechanism. The results further emphasize that direct Fe0-to-microbe electron transfer has yet to be rigorously demonstrated in sulfate-reducing microbes.
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