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Yang C, Zhang J, Zhang B, Liu D, Jia J, Li F, Song H. Engineering Shewanella carassii, a newly isolated exoelectrogen from activated sludge, to enhance methyl orange degradation and bioelectricity harvest. Synth Syst Biotechnol 2022; 7:918-927. [PMID: 35664929 PMCID: PMC9149024 DOI: 10.1016/j.synbio.2022.04.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 12/04/2022] Open
Abstract
Electroactive microorganisms (EAMs) play important roles in biogeochemical redox processes and have been of great interest in the fields of energy recovery, waste treatment, and environmental remediation. However, the currently identified EAMs are difficult to be widely used in complex and diverse environments, due to the existence of poor electron transfer capability, weak environmental adaptability, and difficulty with engineering modifications, etc. Therefore, rapid and efficient screening of high performance EAMs from environments is an effective strategy to facilitate applications of microbial fuel cells (MFCs). In this study, to achieve efficient degradation of methyl orange (MO) by MFC and electricity harvest, a more efficient exoelectrogen Shewanella carassii-D5 that belongs to Shewanella spp. was first isolated from activated sludge by WO3 nanocluster probe technique. Physiological properties experiments confirmed that S. carassii-D5 is a Gram-negative strain with rounded colonies and smooth, slightly reddish surface, which could survive in media containing lactate at 30 °C. Moreover, we found that S. carassii-D5 exhibited remarkable MO degradation ability, which could degrade 66% of MO within 72 h, 1.7 times higher than that of Shewanella oneidensis MR-1. Electrochemical measurements showed that MFCs inoculated with S. carassii-D5 could generate a maximum power density of 704.6 mW/m2, which was 5.6 times higher than that of S. oneidensis MR-1. Further investigation of the extracellular electron transfer (EET) mechanism found that S. carassii-D5 strain had high level of c-type cytochromes and strong biofilm formation ability compared with S. oneidensis MR-1, thus facilitating direct EET. Therefore, to enhance indirect electron transfer and MO degradation capacity, a synthetic gene cluster ribADEHC encoding riboflavin synthesis pathway from Bacillus subtilis was heterologously expressed in S. carassii-D5, increasing riboflavin yield from 1.9 to 9.0 mg/g DCW with 1286.3 mW/m2 power density output in lactate fed-MFCs. Furthermore, results showed that the high EET rate endowed a faster degradation efficient of MO from 66% to 86% with a maximum power density of 192.3 mW/m2, which was 1.3 and 1.6 times higher than that of S. carassii-D5, respectively. Our research suggests that screening and engineering high-efficient EAMs from sludge is a feasible strategy in treating organic pollutants.
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Affiliation(s)
- Chi Yang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Qingdao Institute Ocean Engineering of Tianjin University, Tianjin University, Qingdao, 266200, China
| | - Junqi Zhang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Baocai Zhang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Dingyuan Liu
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Jichao Jia
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Feng Li
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Qingdao Institute Ocean Engineering of Tianjin University, Tianjin University, Qingdao, 266200, China
- Corresponding author. Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.
| | - Hao Song
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Qingdao Institute Ocean Engineering of Tianjin University, Tianjin University, Qingdao, 266200, China
- Corresponding author. Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.
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Tian X, Wu R, Li X, Wu X, Jiang Y, Zhao F. Feedback current production by a ferrous mediator revealing the redox properties of Shewanella oneidensis MR-1. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Conners EM, Rengasamy K, Bose A. "Electroactive biofilms: how microbial electron transfer enables bioelectrochemical applications". J Ind Microbiol Biotechnol 2022; 49:6563884. [PMID: 35381088 PMCID: PMC9338886 DOI: 10.1093/jimb/kuac012] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/30/2022] [Indexed: 11/22/2022]
Abstract
Microbial biofilms are ubiquitous. In marine and freshwater ecosystems, microbe–mineral interactions sustain biogeochemical cycles, while biofilms found on plants and animals can range from pathogens to commensals. Moreover, biofouling and biocorrosion represent significant challenges to industry. Bioprocessing is an opportunity to take advantage of biofilms and harness their utility as a chassis for biocommodity production. Electrochemical bioreactors have numerous potential applications, including wastewater treatment and commodity production. The literature examining these applications has demonstrated that the cell–surface interface is vital to facilitating these processes. Therefore, it is necessary to understand the state of knowledge regarding biofilms’ role in bioprocessing. This mini-review discusses bacterial biofilm formation, cell–surface redox interactions, and the role of microbial electron transfer in bioprocesses. It also highlights some current goals and challenges with respect to microbe-mediated bioprocessing and future perspectives.
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Affiliation(s)
- Eric M Conners
- Department of Biology. One Brookings Drive, Washington University in St. Louis, Missouri, 63105, USA
| | - Karthikeyan Rengasamy
- Department of Biology. One Brookings Drive, Washington University in St. Louis, Missouri, 63105, USA
| | - Arpita Bose
- Department of Biology. One Brookings Drive, Washington University in St. Louis, Missouri, 63105, USA
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Thapa BS, Kim T, Pandit S, Song YE, Afsharian YP, Rahimnejad M, Kim JR, Oh SE. Overview of electroactive microorganisms and electron transfer mechanisms in microbial electrochemistry. BIORESOURCE TECHNOLOGY 2022; 347:126579. [PMID: 34921921 DOI: 10.1016/j.biortech.2021.126579] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 06/14/2023]
Abstract
Electroactive microorganisms acting as microbial electrocatalysts have intrinsic metabolisms that mediate a redox potential difference between solid electrodes and microbes, leading to spontaneous electron transfer to the electrode (exo-electron transfer) or electron uptake from the electrode (endo-electron transfer). These microbes biochemically convert various organic and/or inorganic compounds to electricity and/or biochemicals in bioelectrochemical systems (BESs) such as microbial fuel cells (MFCs) and microbial electrosynthesis cells (MECs). For the past two decades, intense studies have converged to clarify electron transfer mechanisms of electroactive microbes in BESs, which thereby have led to improved bioelectrochemical performance. Also, many novel exoelectrogenic eukaryotes as well as prokaryotes with electroactive properties are being continuously discovered. This review presents an overview of electroactive microorganisms (bacteria, microalgae and fungi) and their exo- and endo-electron transfer mechanisms in BESs for optimizing and advancing bioelectrochemical techniques.
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Affiliation(s)
- Bhim Sen Thapa
- Department of Biological Environment, Kangwon National University, Chuncheon, Gangwondo 24341, Republic of Korea
| | - Taeyoung Kim
- Department of Environmental Engineering, Chosun University, Gwangju 61452, Republic of Korea
| | - Soumya Pandit
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida 201306, India
| | - Young Eun Song
- Advanced Biofuel and Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Emeryville, CA 94608, USA
| | - Yasamin Pesaran Afsharian
- Biofuel and Renewable Energy Research Center, Chemical Engineering Department, Babol Noshirvani University of Technology, Babol, Iran
| | - Mostafa Rahimnejad
- Biofuel and Renewable Energy Research Center, Chemical Engineering Department, Babol Noshirvani University of Technology, Babol, Iran
| | - Jung Rae Kim
- School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Sang-Eun Oh
- Department of Biological Environment, Kangwon National University, Chuncheon, Gangwondo 24341, Republic of Korea.
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Partipilo G, Graham AJ, Belardi B, Keitz BK. Extracellular Electron Transfer Enables Cellular Control of Cu(I)-Catalyzed Alkyne-Azide Cycloaddition. ACS CENTRAL SCIENCE 2022; 8:246-257. [PMID: 35233456 PMCID: PMC8875427 DOI: 10.1021/acscentsci.1c01208] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Indexed: 05/03/2023]
Abstract
Extracellular electron transfer (EET) is an anaerobic respiration process that couples carbon oxidation to the reduction of metal species. In the presence of a suitable metal catalyst, EET allows for cellular metabolism to control a variety of synthetic transformations. Here, we report the use of EET from the electroactive bacterium Shewanella oneidensis for metabolic and genetic control over Cu(I)-catalyzed alkyne-azide cycloaddition (CuAAC). CuAAC conversion under anaerobic and aerobic conditions was dependent on live, actively respiring S. oneidensis cells. The reaction progress and kinetics were manipulated by tailoring the central carbon metabolism. Similarly, EET-CuAAC activity was dependent on specific EET pathways that could be regulated via inducible expression of EET-relevant proteins: MtrC, MtrA, and CymA. EET-driven CuAAC exhibited modularity and robustness in the ligand and substrate scope. Furthermore, the living nature of this system could be exploited to perform multiple reaction cycles without regeneration, something inaccessible to traditional chemical reductants. Finally, S. oneidensis enabled bioorthogonal CuAAC membrane labeling on live mammalian cells without affecting cell viability, suggesting that S. oneidensis can act as a dynamically tunable biocatalyst in complex environments. In summary, our results demonstrate how EET can expand the reaction scope available to living systems by enabling cellular control of CuAAC.
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Affiliation(s)
- Gina Partipilo
- McKetta
Department of Chemical Engineering, University
of Texas at Austin, Austin, Texas 78712, United States
- Center
for Dynamics and Control of Materials, University
of Texas at Austin, Austin, Texas 78712, United States
| | - Austin J. Graham
- McKetta
Department of Chemical Engineering, University
of Texas at Austin, Austin, Texas 78712, United States
- Center
for Dynamics and Control of Materials, University
of Texas at Austin, Austin, Texas 78712, United States
| | - Brian Belardi
- McKetta
Department of Chemical Engineering, University
of Texas at Austin, Austin, Texas 78712, United States
| | - Benjamin K. Keitz
- McKetta
Department of Chemical Engineering, University
of Texas at Austin, Austin, Texas 78712, United States
- Center
for Dynamics and Control of Materials, University
of Texas at Austin, Austin, Texas 78712, United States
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Zhang ZB, Cheng ZH, Wu JH, Yue ZB, Wang J, Liu DF. Engineering of salt-tolerant Shewanella aquimarina XMS-1 for enhanced pollutants transformation and electricity generation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:151009. [PMID: 34662622 DOI: 10.1016/j.scitotenv.2021.151009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/09/2021] [Accepted: 10/11/2021] [Indexed: 06/13/2023]
Abstract
Saline wastewater poses a challenge during bio-treatment process due to salinity affecting the physiological activity of microorganisms and inhibiting their growth and metabolism. Thus, screening and engineering the salt-tolerant strains with stronger performances are urgent. Shewanella aquimarina XMS-1, a salt-tolerant dissimilated metal reducing bacteria (DMRB), was isolated from seawater environment. Its ability for reducing pollutants and generating electricity was enhanced by overexpression of riboflavin synthesis pathway encoding genes from S. oneidensis MR-1 under salt stress. Furthermore, upon contact with graphene oxide (GO), the engineered strain XMS-1/pYYDT-rib with enhanced flavins synthesis could reduce GO and self-assemble to form a three-dimensional (3D) biohybrid system named XMS-1/flavins/rGO. This 3D biohybrid system significantly enhanced the EET efficiency of S. aquimarina XMS-1. Our findings provide a feasible strategy for treatment of salt-containing industrial wastewater contaminated by metal and organic pollutants.
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Affiliation(s)
- Zong-Bin Zhang
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Zhou-Hua Cheng
- School of Life Sciences, University of Science & Technology of China, Hefei 230026, China
| | - Jing-Hang Wu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science & Technology of China, Hefei 230026, China
| | - Zheng-Bo Yue
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Jin Wang
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China.
| | - Dong-Feng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science & Technology of China, Hefei 230026, China.
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57
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Graham AJ, Gibbs SL, Saez Cabezas CA, Wang Y, Green AM, Milliron DJ, Keitz BK. In Situ
Optical Quantification of Extracellular Electron Transfer Using Plasmonic Metal Oxide Nanocrystals**. ChemElectroChem 2022. [DOI: 10.1002/celc.202101423] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Austin J. Graham
- McKetta Department of Chemical Engineering University of Texas at Austin TX, 78712 Austin United States
- Center for the Dynamics and Control of Materials University of Texas at Austin TX, 78712 Austin United States
| | - Stephen L. Gibbs
- McKetta Department of Chemical Engineering University of Texas at Austin TX, 78712 Austin United States
| | - Camila A. Saez Cabezas
- McKetta Department of Chemical Engineering University of Texas at Austin TX, 78712 Austin United States
- Center for the Dynamics and Control of Materials University of Texas at Austin TX, 78712 Austin United States
| | - Yongdan Wang
- McKetta Department of Chemical Engineering University of Texas at Austin TX, 78712 Austin United States
| | - Allison M. Green
- McKetta Department of Chemical Engineering University of Texas at Austin TX, 78712 Austin United States
- Center for the Dynamics and Control of Materials University of Texas at Austin TX, 78712 Austin United States
| | - Delia J. Milliron
- McKetta Department of Chemical Engineering University of Texas at Austin TX, 78712 Austin United States
- Center for the Dynamics and Control of Materials University of Texas at Austin TX, 78712 Austin United States
| | - Benjamin K. Keitz
- McKetta Department of Chemical Engineering University of Texas at Austin TX, 78712 Austin United States
- Center for the Dynamics and Control of Materials University of Texas at Austin TX, 78712 Austin United States
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58
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Nagendranatha Reddy C, Kondaveeti S, Mohanakrishna G, Min B. Application of bioelectrochemical systems to regulate and accelerate the anaerobic digestion processes. CHEMOSPHERE 2022; 287:132299. [PMID: 34627010 DOI: 10.1016/j.chemosphere.2021.132299] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 08/23/2021] [Accepted: 09/17/2021] [Indexed: 06/13/2023]
Abstract
Anaerobic digestion (AD) serves as a potential bioconversion process to treat various organic wastes/wastewaters, including sewage sludge, and generate renewable green energy. Despite its efficiency, AD has several limitations that need to be overcome to achieve maximum energy recovery from organic materials while regulating inhibitory substances. Hence, bioelectrochemical systems (BESs) have been widely investigated to treat inhibitory compounds including ammonia in AD processes and improve the AD operational efficiency, stability, and economic viability with various integrations. The BES operations as a pretreatment process, inside AD or after the AD process aids in the upgradation of biogas (CO2 to methane) and residual volatile fatty acids (VFAs) to valuable chemicals and fuels (alcohols) and even directly to electricity generation. This review presents a comprehensive summary of BES technologies and operations for overcoming the limitations of AD in lab-scale applications and suggests upscaling and future opportunities for BES-AD systems.
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Affiliation(s)
- C Nagendranatha Reddy
- Department of Environmental Science and Engineering, Kyung Hee University, Seocheon-dong, Yongin-si, Gyeonggi-do, 446-701, Republic of Korea; Department of Biotechnology, Chaitanya Bharathi Institute of Technology (Autonomous), Gandipet, 500075, Hyderabad, Telangana State, India
| | - Sanath Kondaveeti
- Division of Chemical Engineering, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul, 05029, South Korea
| | | | - Booki Min
- Department of Environmental Science and Engineering, Kyung Hee University, Seocheon-dong, Yongin-si, Gyeonggi-do, 446-701, Republic of Korea.
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59
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Abel AJ, Hilzinger JM, Arkin AP, Clark DS. Systems-informed genome mining for electroautotrophic microbial production. Bioelectrochemistry 2022; 145:108054. [DOI: 10.1016/j.bioelechem.2022.108054] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 12/15/2021] [Accepted: 01/06/2022] [Indexed: 01/09/2023]
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Hu Y, Wang Y, Han X, Shan Y, Li F, Shi L. Biofilm Biology and Engineering of Geobacter and Shewanella spp. for Energy Applications. Front Bioeng Biotechnol 2021; 9:786416. [PMID: 34926431 PMCID: PMC8683041 DOI: 10.3389/fbioe.2021.786416] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/18/2021] [Indexed: 01/04/2023] Open
Abstract
Geobacter and Shewanella spp. were discovered in late 1980s as dissimilatory metal-reducing microorganisms that can transfer electrons from cytoplasmic respiratory oxidation reactions to external metal-containing minerals. In addition to mineral-based electron acceptors, Geobacter and Shewanella spp. also can transfer electrons to electrodes. The microorganisms that have abilities to transfer electrons to electrodes are known as exoelectrogens. Because of their remarkable abilities of electron transfer, Geobacter and Shewanella spp. have been the two most well studied groups of exoelectrogens. They are widely used in bioelectrochemical systems (BESs) for various biotechnological applications, such as bioelectricity generation via microbial fuel cells. These applications mostly associate with Geobacter and Shewanella biofilms grown on the surfaces of electrodes. Geobacter and Shewanella biofilms are electrically conductive, which is conferred by matrix-associated electroactive components such as c-type cytochromes and electrically conductive nanowires. The thickness and electroactivity of Geobacter and Shewanella biofilms have a significant impact on electron transfer efficiency in BESs. In this review, we first briefly discuss the roles of planktonic and biofilm-forming Geobacter and Shewanella cells in BESs, and then review biofilm biology with the focus on biofilm development, biofilm matrix, heterogeneity in biofilm and signaling regulatory systems mediating formation of Geobacter and Shewanella biofilms. Finally, we discuss strategies of Geobacter and Shewanella biofilm engineering for improving electron transfer efficiency to obtain enhanced BES performance.
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Affiliation(s)
- Yidan Hu
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Yinghui Wang
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Xi Han
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Yawei Shan
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Feng Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Liang Shi
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China.,State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China.,Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, China University of Geosciences, Wuhan, China.,State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution, Ministry of Ecology and Environment, Wuhan, China
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61
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Bird LJ, Kundu BB, Tschirhart T, Corts AD, Su L, Gralnick JA, Ajo-Franklin CM, Glaven SM. Engineering Wired Life: Synthetic Biology for Electroactive Bacteria. ACS Synth Biol 2021; 10:2808-2823. [PMID: 34637280 DOI: 10.1021/acssynbio.1c00335] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Electroactive bacteria produce or consume electrical current by moving electrons to and from extracellular acceptors and donors. This specialized process, known as extracellular electron transfer, relies on pathways composed of redox active proteins and biomolecules and has enabled technologies ranging from harvesting energy on the sea floor, to chemical sensing, to carbon capture. Harnessing and controlling extracellular electron transfer pathways using bioengineering and synthetic biology promises to heighten the limits of established technologies and open doors to new possibilities. In this review, we provide an overview of recent advancements in genetic tools for manipulating native electroactive bacteria to control extracellular electron transfer. After reviewing electron transfer pathways in natively electroactive organisms, we examine lessons learned from the introduction of extracellular electron transfer pathways into Escherichia coli. We conclude by presenting challenges to future efforts and give examples of opportunities to bioengineer microbes for electrochemical applications.
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Affiliation(s)
- Lina J. Bird
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Biki B. Kundu
- PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, Texas 77005, United States
| | - Tanya Tschirhart
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Anna D. Corts
- Joyn Bio, Boston, Massachusetts 02210, United States
| | - Lin Su
- State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210018, People’s Republic of China
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Jeffrey A. Gralnick
- Department of Plant and Microbial Biology, BioTechnology Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
| | | | - Sarah M. Glaven
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, D.C. 20375, United States
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62
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Das S, Das S, Ghangrekar MM. Bacterial signalling mechanism: An innovative microbial intervention with multifaceted applications in microbial electrochemical technologies: A review. BIORESOURCE TECHNOLOGY 2021; 344:126218. [PMID: 34728350 DOI: 10.1016/j.biortech.2021.126218] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 02/05/2023]
Abstract
Microbial electrochemical technologies (METs) are a set of inventive tools that generate value-added by-products with concomitant wastewater remediation. However, due to the bottlenecks, like higher fabrication cost and inferior yield of resources, these inventive METs are still devoid of successful field-scale implementation. In this regard, application of quorum sensing (QS) mechanism to improve the power generation of the METs has gained adequate attention. The QS is an intercellular signalling mechanism that controls the bacterial social network in its vicinity via the synthesis of diffusible signal molecules labelled as auto inducers, thus ameliorating yield of valuables produced through METs. This state-of-the-art review elucidates different types of QS molecules and their working mechanism with the special focus on the widespread application of QS in the field of METs for their performance enhancement. Thus, this review intends to guide the researchers in rendering scalability to METs by integrating innovative QS mechanisms into them.
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Affiliation(s)
- Swati Das
- PK Sinha Centre for Bioenergy & Renewables, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Sovik Das
- Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur 21302, West Bengal, India
| | - M M Ghangrekar
- PK Sinha Centre for Bioenergy & Renewables, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India; Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur 21302, West Bengal, India.
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63
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Gurumurthy DM, Bilal M, Nadda AK, Reddy VD, Saratale GD, Guzik U, Ferreira LFR, Gupta SK, Savanur MA, Mulla SI. Evaluation of cell wall-associated direct extracellular electron transfer in thermophilic Geobacillus sp. 3 Biotech 2021; 11:383. [PMID: 34350088 DOI: 10.1007/s13205-021-02917-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 07/05/2021] [Indexed: 11/25/2022] Open
Abstract
In this study, a cell wall-associated extracellular electron transfer (EET) was determined in the thermophilic Geobacillus sp. to utilize iron as a terminal electron acceptor. The direct extracellular transfer of its electrons was primarily linked to the cell wall cytochrome-c and diffusible redox mediators like flavins during the anoxic condition. Based on the azo dye decolouration and protein film voltammetry, it was revealed that, in the absence of surface polysaccharide and diffusible mediators, the cell wall-associated EET pathway was likely to be a favorable mechanism in Geobacillus sp. Since the permeability of such redox molecule is primarily limited to the cell wall, the electron transfer occurs by direct contact with cell wall-associated cytochrome and final electron acceptor. Furthermore, transfer of electrons with the help of redox shuttling molecules like riboflavin from cytochrome to cells, vice versa indicates that Geoabcillus sp. has adopted this unique pathway during an anoxic environment for its respiration. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13205-021-02917-2.
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Affiliation(s)
| | - Muhammad Bilal
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, China
| | - Ashok Kumar Nadda
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat, Solan, 173234 Himachal Pradesh India
| | - Vaddi Damodara Reddy
- Department of Biochemistry, School of Applied Sciences, REVA University, Bangalore, 560 064 India
| | - Ganesh Dattatraya Saratale
- Department of Food Science and Biotechnology, Dongguk University-Seoul, Ilsandong-gu, Goyang, Gyeonggi 10326 Republic of Korea
| | - Urszula Guzik
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Science , University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland
| | - Luiz Fernando Romanholo Ferreira
- Graduate Program in Process Engineering , Tiradentes University, Av. Murilo Dantas, 300, Farolândia, Aracaju, Sergipe 49032-490 Brazil
| | - Sanjay Kumar Gupta
- Environmental Engineering, Department of Civil Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016 India
| | | | - Sikandar I Mulla
- Department of Biochemistry, School of Applied Sciences, REVA University, Bangalore, 560 064 India
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Mukherjee P, Pichiah S, Packirisamy G, Jang M. Biocatalyst physiology and interplay: a protagonist of MFC operation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:43217-43233. [PMID: 34165738 DOI: 10.1007/s11356-021-15015-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
Microbial fuel cells (MFC) have been foreseen as a sustainable renewable energy resource to meet future energy demand. In the past, several studies have been executed in both benchtop and pilot scale to produce electrical energy from wastewater. The key role players in this technology that leads to the operation are microbes, mainly bacteria. The dominant among them is termed as "exoelectrogens" that have the capability to produce and transport electron by utilizing waste source. The current review focuses on such electrogenic bacteria's involvement for enhanced power generation of MFC. The pathway of electron transfer in their cell along and its conduction to the extracellular environment of the MFC system are critically discussed. The interaction of the microbes in various MFC operational conditions, including the role of substrate and solid electron acceptors, i.e., anode, external resistance, temperature, and pH, was also discussed in depth along with biotechnological advancement and future research perspective.
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Affiliation(s)
- Priya Mukherjee
- Environmental Nanotechnology Laboratory, Department of Environmental Science and Engineering, Indian Institute of Technology (ISM), Dhanbad, Jharkhand, 826004, India
| | - Saravanan Pichiah
- Environmental Nanotechnology Laboratory, Department of Environmental Science and Engineering, Indian Institute of Technology (ISM), Dhanbad, Jharkhand, 826004, India.
| | - Gopinath Packirisamy
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Min Jang
- Department of Environmental Engineering, Kwangwoon University, 447-1, Wolgye-dong Nowon-Gu, Seoul, South Korea
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65
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Xie J, Wang J, Lin J. New insights into the role of calcium in the bioreduction of uranium(VI) under varying pH conditions. JOURNAL OF HAZARDOUS MATERIALS 2021; 411:125140. [PMID: 33858102 DOI: 10.1016/j.jhazmat.2021.125140] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 12/22/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
The effect of calcium in the uranium-contaminated groundwater on U(VI)aq bioreduction remains uncertain. Some studies indicated that the presence of calcium may inhibit the bioreduction. However, our calculations show the negative standard molar Gibbs free energy of reduction. The bioreduction of the ternary uranyl-carbonate-calcium complexes seems thermodynamically favorable at specific pH. Sorption and reduction experiments were conducted to gain new insights of calcium into the bioreduction. The results show that the complexes were greatly reduced by Shewanella putrefaciens in the slightly acidic pH ~6.0 and alkaline pH ~7.9 solutions with the relatively high CaCl2 (1.0-6.0 mmol/L) although the reduction was difficult at the nearly neutral pH ~6.9. At pH ~6.9, the removal percentage of U(VI)aq decreased from 97.0% to 24.4% with increasing CaCl2 from 0 to 6.0 mmol/L, in contrast to the increasing percentage from 50.9% to 89.7% at pH ~7.9. The obvious removal of U(VI)aq was ascribed to the bioreduction instead of the biosorption, as evidenced by XPS, HRTEM and UV-vis spectra. The calculations such as [Formula: see text] and [Formula: see text] partially accounted for the reduction mechanisms. Accordingly, the U(VI)aq bioreduction is a promising method to remediate the groundwater even rich in calcium and carbonate.
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Affiliation(s)
- Jinchuan Xie
- Institute of Military-Civilian Integration Technology, Northwest University of Political Science and Law, Xi'an, Shanxi 710122, China.
| | - Jinlong Wang
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an, Shanxi 710024, China
| | - Jianfeng Lin
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an, Shanxi 710024, China
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66
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Boedicker JQ, Gangan M, Naughton K, Zhao F, Gralnick JA, El-Naggar MY. Engineering Biological Electron Transfer and Redox Pathways for Nanoparticle Synthesis. Bioelectricity 2021; 3:126-135. [PMID: 34476388 DOI: 10.1089/bioe.2021.0010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Many species of bacteria are naturally capable of types of electron transport not observed in eukaryotic cells. Some species live in environments containing heavy metals not typically encountered by cells of multicellular organisms, such as arsenic, cadmium, and mercury, leading to the evolution of enzymes to deal with these environmental toxins. Bacteria also inhabit a variety of extreme environments, and are capable of respiration even in the absence of oxygen as a terminal electron acceptor. Over the years, several of these exotic redox and electron transport pathways have been discovered and characterized in molecular-level detail, and more recently synthetic biology has begun to utilize these pathways to engineer cells capable of detecting and processing a variety of metals and semimetals. One such application is the biologically controlled synthesis of nanoparticles. This review will introduce the basic concepts of bacterial metal reduction, summarize recent work in engineering bacteria for nanoparticle production, and highlight the most cutting-edge work in the characterization and application of bacterial electron transport pathways.
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Affiliation(s)
- James Q Boedicker
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, USA.,Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Manasi Gangan
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, USA
| | - Kyle Naughton
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, USA
| | - Fengjie Zhao
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, USA
| | - Jeffrey A Gralnick
- BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, USA.,Department of Plant and Microbial Biology, University of Minnesota-Twin Cities, St. Paul, Minnesota, USA
| | - Mohamed Y El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, USA.,Department of Biological Sciences, University of Southern California, Los Angeles, California, USA.,Department of Chemistry, University of Southern California, Los Angeles, California, USA
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67
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Engineering Cooperation in an Anaerobic Coculture. Appl Environ Microbiol 2021; 87:AEM.02852-20. [PMID: 33771781 DOI: 10.1128/aem.02852-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 03/19/2021] [Indexed: 01/28/2023] Open
Abstract
Over the past century, microbiologists have studied organisms in pure culture, yet it is becoming increasingly apparent that the majority of biological processes rely on multispecies cooperation and interaction. While little is known about how such interactions permit cooperation, even less is known about how cooperation arises. To study the emergence of cooperation in the laboratory, we constructed both a commensal community and an obligate mutualism using the previously noninteracting bacteria Shewanella oneidensis and Geobacter sulfurreducens Incorporation of a glycerol utilization plasmid (pGUT2) enabled S. oneidensis to metabolize glycerol and produce acetate as a carbon source for G. sulfurreducens, establishing a cross-feeding, commensal coculture. In the commensal coculture, both species coupled oxidative metabolism to the respiration of fumarate as the terminal electron acceptor. Deletion of the gene encoding fumarate reductase in the S. oneidensis/pGUT2 strain shifted the coculture with G. sulfurreducens to an obligate mutualism where neither species could grow in the absence of the other. A shift in metabolic strategy from glycerol catabolism to malate metabolism was associated with obligate coculture growth. Further targeted deletions in malate uptake and acetate generation pathways in S. oneidensis significantly inhibited coculture growth with G. sulfurreducens The engineered coculture between S. oneidensis and G. sulfurreducens provides a model laboratory system to study the emergence of cooperation in bacterial communities, and the shift in metabolic strategy observed in the obligate coculture highlights the importance of genetic change in shaping microbial interactions in the environment.IMPORTANCE Microbes seldom live alone in the environment, yet this scenario is approximated in the vast majority of pure-culture laboratory experiments. Here, we develop an anaerobic coculture system to begin understanding microbial physiology in a more complex setting but also to determine how anaerobic microbial communities can form. Using synthetic biology, we generated a coculture system where the facultative anaerobe Shewanella oneidensis consumes glycerol and provides acetate to the strict anaerobe Geobacter sulfurreducens In the commensal system, growth of G. sulfurreducens is dependent on the presence of S. oneidensis To generate an obligate coculture, where each organism requires the other, we eliminated the ability of S. oneidensis to respire fumarate. An unexpected shift in metabolic strategy from glycerol catabolism to malate metabolism was observed in the obligate coculture. Our work highlights how metabolic landscapes can be expanded in multispecies communities and provides a system to evaluate the evolution of cooperation under anaerobic conditions.
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Kees ED, Levar CE, Miller SP, Bond DR, Gralnick JA, Dean AM. Survival of the first rather than the fittest in a Shewanella electrode biofilm. Commun Biol 2021; 4:536. [PMID: 33958697 PMCID: PMC8102560 DOI: 10.1038/s42003-021-02040-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 03/22/2021] [Indexed: 11/09/2022] Open
Abstract
For natural selection to operate there must exist heritable variation among individuals that affects their survival and reproduction. Among free-living microbes, where differences in growth rates largely define selection intensities, competitive exclusion is common. However, among surface attached communities, these dynamics become less predictable. If extreme circumstances were to dictate that a surface population is immortal and all offspring must emigrate, the offspring would be unable to contribute to the composition of the population. Meanwhile, the immortals, regardless of reproductive capacity, would remain unchanged in relative abundance. The normal cycle of birth, death, and competitive exclusion would be broken. We tested whether conditions required to set up this idealized scenario can be approximated in a microbial biofilm. Using two differentially-reproducing strains of Shewanella oneidensis grown on an anode as the sole terminal electron acceptor - a system in which metabolism is obligately tied to surface attachment - we found that selection against a slow-growing competitor is drastically reduced. This work furthers understanding of natural selection dynamics in sessile microbial communities, and provides a framework for designing stable microbial communities for industrial and experimental applications.
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Affiliation(s)
- Eric D Kees
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Caleb E Levar
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Stephen P Miller
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA
| | - Daniel R Bond
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Jeffrey A Gralnick
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA.
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA.
| | - Antony M Dean
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA.
- Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA.
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69
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Zou L, Zhu F, Long ZE, Huang Y. Bacterial extracellular electron transfer: a powerful route to the green biosynthesis of inorganic nanomaterials for multifunctional applications. J Nanobiotechnology 2021; 19:120. [PMID: 33906693 PMCID: PMC8077780 DOI: 10.1186/s12951-021-00868-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 04/20/2021] [Indexed: 02/08/2023] Open
Abstract
Synthesis of inorganic nanomaterials such as metal nanoparticles (MNPs) using various biological entities as smart nanofactories has emerged as one of the foremost scientific endeavors in recent years. The biosynthesis process is environmentally friendly, cost-effective and easy to be scaled up, and can also bring neat features to products such as high dispersity and biocompatibility. However, the biomanufacturing of inorganic nanomaterials is still at the trial-and-error stage due to the lack of understanding for underlying mechanism. Dissimilatory metal reduction bacteria, especially Shewanella and Geobacter species, possess peculiar extracellular electron transfer (EET) features, through which the bacteria can pump electrons out of their cells to drive extracellular reduction reactions, and have thus exhibited distinct advantages in controllable and tailorable fabrication of inorganic nanomaterials including MNPs and graphene. Our aim is to present a critical review of recent state-of-the-art advances in inorganic biosynthesis methodologies based on bacterial EET using Shewanella and Geobacter species as typical strains. We begin with a brief introduction about bacterial EET mechanism, followed by reviewing key examples from literatures that exemplify the powerful activities of EET-enabled biosynthesis routes towards the production of a series of inorganic nanomaterials and place a special emphasis on rationally tailoring the structures and properties of products through the fine control of EET pathways. The application prospects of biogenic nanomaterials are then highlighted in multiple fields of (bio-) energy conversion, remediation of organic pollutants and toxic metals, and biomedicine. A summary and outlook are given with discussion on challenges of bio-manufacturing with well-defined controllability. ![]()
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Affiliation(s)
- Long Zou
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization From Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China
| | - Fei Zhu
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization From Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China
| | - Zhong-Er Long
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization From Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China
| | - Yunhong Huang
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization From Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China.
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Sheik CS, Badalamenti JP, Telling J, Hsu D, Alexander SC, Bond DR, Gralnick JA, Lollar BS, Toner BM. Novel Microbial Groups Drive Productivity in an Archean Iron Formation. Front Microbiol 2021; 12:627595. [PMID: 33859627 PMCID: PMC8042283 DOI: 10.3389/fmicb.2021.627595] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 03/01/2021] [Indexed: 12/23/2022] Open
Abstract
Deep subsurface environments are decoupled from Earth's surface processes yet diverse, active, and abundant microbial communities thrive in these isolated environments. Microbes inhabiting the deep biosphere face unique challenges such as electron donor/acceptor limitations, pore space/fracture network limitations, and isolation from other microbes within the formation. Of the few systems that have been characterized, it is apparent that nutrient limitations likely facilitate diverse microbe-microbe interactions (i.e., syntrophic, symbiotic, or parasitic) and that these interactions drive biogeochemical cycling of major elements. Here we describe microbial communities living in low temperature, chemically reduced brines at the Soudan Underground Mine State Park, United States. The Soudan Iron mine intersects a massive hematite formation at the southern extent of the Canadian Shield. Fractured rock aquifer brines continuously flow from exploratory boreholes drilled circa 1960 and are enriched in deuterium compared to the global meteoric values, indicating brines have had little contact with surface derived waters, and continually degas low molecular weight hydrocarbons C1-C4. Microbial enrichments suggest that once brines exit the boreholes, oxidation of the hydrocarbons occur. Amplicon sequencing show these borehole communities are low in diversity and dominated by Firmicute and Proteobacteria phyla. From the metagenome assemblies, we recovered approximately thirty genomes with estimated completion over 50%. Analysis of genome taxonomy generally followed the amplicon data, and highlights that several of the genomes represent novel families and genera. Metabolic reconstruction shows two carbon-fixation pathways were dominant, the Wood-Ljungdahl (acetogenesis) and Calvin-Benson-Bassham (via RuBisCo), indicating that inorganic carbon likely enters into the microbial foodweb with differing carbon fractionation potentials. Interestingly, methanogenesis is likely driven by Methanolobus and suggests cycling of methylated compounds and not H2/CO2 or acetate. Furthermore, the abundance of sulfate in brines suggests cryptic sulfur cycling may occur, as we detect possible sulfate reducing and thiosulfate oxidizing microorganisms. Finally, a majority of the microorganisms identified contain genes that would allow them to participate in several element cycles, highlighting that in these deep isolated systems metabolic flexibility may be an important life history trait.
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Affiliation(s)
- Cody S. Sheik
- Department of Biology and the Large Lakes Observatory, University of Minnesota Duluth, Duluth, MN, United States
| | - Jonathan P. Badalamenti
- University of Minnesota Genomics Center, University of Minnesota Twin Cities, Minneapolis, MN, United States
- Biotechnology Institute, University of Minnesota Twin Cities, Saint Paul, MN, United States
| | - Jon Telling
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - David Hsu
- Biotechnology Institute, University of Minnesota Twin Cities, Saint Paul, MN, United States
- Plant and Microbial Biology, University of Minnesota Twin Cities, Saint Paul, MN, United States
| | - Scott C. Alexander
- Department of Earth and Environmental Sciences, University of Minnesota Twin Cities, Minneapolis, MN, United States
| | - Daniel R. Bond
- Biotechnology Institute, University of Minnesota Twin Cities, Saint Paul, MN, United States
- Plant and Microbial Biology, University of Minnesota Twin Cities, Saint Paul, MN, United States
| | - Jeffrey A. Gralnick
- Biotechnology Institute, University of Minnesota Twin Cities, Saint Paul, MN, United States
- Plant and Microbial Biology, University of Minnesota Twin Cities, Saint Paul, MN, United States
| | | | - Brandy M. Toner
- Department of Earth and Environmental Sciences, University of Minnesota Twin Cities, Minneapolis, MN, United States
- Department of Soil, Water, and Climate, University of Minnesota Twin Cities, Saint Paul, MN, United States
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71
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Yuan Q, Wang S, Wang X, Li N. Biosynthesis of vivianite from microbial extracellular electron transfer and environmental application. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 762:143076. [PMID: 33129535 DOI: 10.1016/j.scitotenv.2020.143076] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/01/2020] [Accepted: 10/11/2020] [Indexed: 06/11/2023]
Abstract
Vivianite (Fe3(PO4)2·8H2O) is a common hydrous ferrous phosphate mineral which often occurs in reductive conditions, especially anoxic non-sulfide environment containing high concentrations of ferrous iron (Fe2+) and orthophosphate (PO43-). Vivianite is an important product of dissimilatory iron reduction and a promising route for phosphorus recovery from wastewater. Its formation is closely related to the extracellular electron transfer (EET), a key mechanism for microbial respiration and a crucial explanation for the reduction of metal oxides in soil and sediments. Despite of the natural ubiquity, easy accessibility and attractive economic value, the application value of vivianite has not received much attention. This review introduces the characteristics, occurrence and biosynthesis of vivianite from microbial EET, and systematically analyzes the application value of vivianite in the environmental field, including immobilization of heavy metals (HMs), dechlorination of carbon tetrachloride (CT), sedimentary phosphorus sequestration and eutrophication alleviation. Additionally, its potential functions as a slow-release fertilizer are discussed as well. In general, vivianite is expected to make more contributions to the future scientific research, especially the solution of environmental problems. Overcoming the lack of understanding and some technical limitations will be beneficial to the further application of vivianite in environmental field.
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Affiliation(s)
- Qing Yuan
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Shu Wang
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Xin Wang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Nan Li
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China.
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Jia Y, Qian D, Chen Y, Hu Y. Intra/extracellular electron transfer for aerobic denitrification mediated by in-situ biosynthesis palladium nanoparticles. WATER RESEARCH 2021; 189:116612. [PMID: 33189971 DOI: 10.1016/j.watres.2020.116612] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/31/2020] [Accepted: 11/05/2020] [Indexed: 06/11/2023]
Abstract
The slow electron transfer rate is the bottleneck to the biological wastewater treatment process, and the nanoparticles (NPs) has been verified as a feasible strategy to improve the biological degradation efficiency by accelerating the electron transfer. Here, we employed the Gram-positive Bacillus megaterium Y-4, capable of synthetizing Pd(0), to investigate the intra/extracellular electron transfer (IET/EET) mechanisms mediated by NPs in aerobic denitrification for the first time. Kinetic and thermodynamic results showed that the bio-Pd(0) could significantly promote the removal of both nitrate and nitrite by improving affinity and decreasing activation energy. The enzymic activity and the respiration chain inhibition experiment indicated that the bio-Pd(0) could facilitate the nitrate biotic reduction by improving the Fe-S center activity and serving as parallel H carriers to replace coenzyme Q to selectively increase the electron flux toward nitrate in IET, while promoting the nitrite reduction by abiotic catalysis. Most importantly, the detection of DPV peak at -226~-287 mV proved that the one-electron EET via multiheme cytochrome-bound flavins also occurred in Gram-positive bacteria and enhanced in Pd-loaded cells. In addition, the remarkable increase of the formal charge in EPS indicated that the bio-Pd(0) could act as an electron shuttle to increase the redox site in EPS, eventually accelerating the electron hopping in long-distance electron transfer. Overall, this study expanded our understanding of the roles of bio-Pd(0) on the aerobic denitrification process and provided an insight into the IET/EET of Gram-positive strains.
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Affiliation(s)
- Yating Jia
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China
| | - Danshi Qian
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China
| | - Yuancai Chen
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
| | - Yongyou Hu
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China
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Xiao X, Ma XL, Wang LG, Long F, Li TT, Zhou XT, Liu H, Wu LJ, Yu HQ. Anaerobic reduction of high-polarity nitroaromatic compounds by electrochemically active bacteria: Roles of Mtr respiratory pathway, molecular polarity, mediator and membrane permeability. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 268:115943. [PMID: 33158624 DOI: 10.1016/j.envpol.2020.115943] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/22/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
Electrochemically active bacteria (EAB) are effective for the bioreduction of nitroaromatic compounds (NACs), but the exact reduction mechanisms are unclear yet. Therefore, 3-nitrobenzenesulfonate (NBS) was used to explore the biodegradation mechanism of NACs by EAB. Results show that NBS could be anaerobically degraded by Shewanella oneidensis MR-1. The generation of aminoaromatic compounds was accompanied with the NBS reduction, indicating that NBS was biodegraded via reductive approach by S. oneidensis MR-1. The impacts of NBS concentration and cell density on the NBS reduction were evaluated. The removal of NBS depends mainly on the transmembrane electron transfer of S. oneidensis MR-1. Impairment of Mtr respiratory pathway was found to mitigate the reduction of NBS, suggesting that the anaerobic biodegradation of NBS occurred extracellularly. Knocking out cymA severely impaired the extracellular reduction ability of S. oneidensis MR-1. However, the phenotype of ΔcymA mutant could be compensated by the exogenous electron mediators, implying the trans-outer membrane diffusion of mediators into the periplasmic space. This work provides a new insight into the anaerobic reduction of aromatic contaminants by EAB.
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Affiliation(s)
- Xiang Xiao
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China; School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Xiao-Lin Ma
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Lu-Guang Wang
- Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR, 97333, USA
| | - Fei Long
- Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR, 97333, USA
| | - Ting-Ting Li
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Xiang-Tong Zhou
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Hong Liu
- Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR, 97333, USA
| | - Li-Jun Wu
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China
| | - Han-Qing Yu
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China; CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, 230026, China.
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Zhao J, Li F, Cao Y, Zhang X, Chen T, Song H, Wang Z. Microbial extracellular electron transfer and strategies for engineering electroactive microorganisms. Biotechnol Adv 2020; 53:107682. [PMID: 33326817 DOI: 10.1016/j.biotechadv.2020.107682] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 11/04/2020] [Accepted: 12/09/2020] [Indexed: 11/27/2022]
Abstract
Electroactive microorganisms (EAMs) are ubiquitous in nature and have attracted considerable attention as they can be used for energy recovery and environmental remediation via their extracellular electron transfer (EET) capabilities. Although the EET mechanisms of Shewanella and Geobacter have been rigorously investigated and are well characterized, much less is known about the EET mechanisms of other microorganisms. For EAMs, efficient EET is crucial for the sustainable economic development of bioelectrochemical systems (BESs). Currently, the low efficiency of EET remains a key factor in limiting the development of BESs. In this review, we focus on the EET mechanisms of different microorganisms, (i.e., bacteria, fungi, and archaea). In addition, we describe in detail three engineering strategies for improving the EET ability of EAMs: (1) enhancing transmembrane electron transport via cytochrome protein channels; (2) accelerating electron transport via electron shuttle synthesis and transmission; and (3) promoting the microbe-electrode interface reaction via regulating biofilm formation. At the end of this review, we look to the future, with an emphasis on the cross-disciplinary integration of systems biology and synthetic biology to build high-performance EAM systems.
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Affiliation(s)
- Juntao Zhao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), SynBioResearch Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
| | - Feng Li
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), SynBioResearch Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
| | - Yingxiu Cao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), SynBioResearch Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
| | - Xinbo Zhang
- Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, Department of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, People's Republic of China
| | - Tao Chen
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), SynBioResearch Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
| | - Hao Song
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), SynBioResearch Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
| | - Zhiwen Wang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), SynBioResearch Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China.
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75
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Engineering S. oneidensis for Performance Improvement of Microbial Fuel Cell-a Mini Review. Appl Biochem Biotechnol 2020; 193:1170-1186. [PMID: 33200267 DOI: 10.1007/s12010-020-03469-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 11/09/2020] [Indexed: 02/02/2023]
Abstract
Microbial fuel cell (MFC) is a promising technology that utilizes exoelectrogens cultivated in the form of biofilm to generate power from various types of sources supplied. A metal-reducing pathway is utilized by these organisms to transfer electrons obtained from the metabolism of substrate from anaerobic respiration extracellularly. A widely established model organism that is capable of extracellular electron transfer (EET) is Shewanella oneidensis. This review highlights the strategies used in the transformation of S. oneidensis and the recent development of MFC in terms of intervention through genetic modifications. S. oneidensis was genetically engineered for several aims including the study on the underlying mechanisms of EET, and the enhancement of power generation and wastewater treating potential when used in an MFC. Through engineering S. oneidensis, genes responsible for EET are identified and strategies on enhancing the EET efficiency are studied. Overexpressing genes related to EET to enhance biofilm formation, mediator biosynthesis, and respiration appears as one of the common approaches.
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76
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Zuo H, Kukkadapu R, Zhu Z, Ni S, Huang L, Zeng Q, Liu C, Dong H. Role of clay-associated humic substances in catalyzing bioreduction of structural Fe(III) in nontronite by Shewanella putrefaciens CN32. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 741:140213. [PMID: 32603937 DOI: 10.1016/j.scitotenv.2020.140213] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/24/2020] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Previous studies have shown that humic substances can serve as electron shuttle to catalyze bioreduction of structural Fe(III) in clay minerals, but it is unclear if clay-sorbed humic substances can serve the same function. It is unknown if the electron shuttling function is dependent on electron donor type and if humic substances undergo change as a result. In this study, humic acid (HA) and fulvic acid (FA) were sorbed onto nontronite (NAu-2) surface. Structural Fe(III) in HA- and FA-coated NAu-2 samples was bioreduced by Shewanella putrefaciens CN32 using H2 and lactate as electron donors. The results showed a contrasting effect of humic substances on bioreduction of structural Fe(III), depending on the electron donor type. With H2 as electron donor, humic substances had little effect on bioreduction of Fe(III) (the reduction extent: 26.2%, 27.4%, 29.3% for HA-coated, FA-coated, and uncoated NAu-2, respectively). In contrast, these substances significantly enhanced bioreduction of Fe(III) with lactate as electron donor (the reduction extent: 20.2%, 20.7%, 11.5% for HA-coated, FA-coated, and uncoated NAu-2, respectively). This contrasting behavior is likely caused by the difference in reaction free energy and electron transport process between H2 and lactate. When H2 served as electron donor, more energy was released than when lactate served as electron donor. In addition, because of different cellular locations of lactate dehydrogenase (inner membrane) and H2 hydrogenase (the periplasm), electrons generated by H2 hydrogenase may pass through the electron transport chain more rapidly than those generated from lactate dehydrogenase. Through their functions as electron shuttle and/or carbon source, clay-sorbed HA/FA underwent partial transformation to amino acids and other compounds. The availability of external carbon source played an important role in the amount and type of secondary product generation. These results have important implications for coupled iron and carbon biogeochemical cycles in clay- and humic substance-rich environments.
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Affiliation(s)
- Hongyan Zuo
- Department of Geology and Environmental Earth Science, Miami University, Oxford, OH 45056, USA
| | - Ravi Kukkadapu
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99354, USA
| | - Zihua Zhu
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99354, USA
| | - Shuisong Ni
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Liuqin Huang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Qiang Zeng
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China
| | - Chongxuan Liu
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hailiang Dong
- Department of Geology and Environmental Earth Science, Miami University, Oxford, OH 45056, USA; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China.
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77
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Chen H, Simoska O, Lim K, Grattieri M, Yuan M, Dong F, Lee YS, Beaver K, Weliwatte S, Gaffney EM, Minteer SD. Fundamentals, Applications, and Future Directions of Bioelectrocatalysis. Chem Rev 2020; 120:12903-12993. [DOI: 10.1021/acs.chemrev.0c00472] [Citation(s) in RCA: 118] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Hui Chen
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Olja Simoska
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Koun Lim
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Matteo Grattieri
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Mengwei Yuan
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Fangyuan Dong
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Yoo Seok Lee
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Kevin Beaver
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Samali Weliwatte
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Erin M. Gaffney
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Shelley D. Minteer
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
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78
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Dundas CM, Walker DJ, Keitz BK. Tuning Extracellular Electron Transfer by Shewanella oneidensis Using Transcriptional Logic Gates. ACS Synth Biol 2020; 9:2301-2315. [PMID: 32786362 DOI: 10.1021/acssynbio.9b00517] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Extracellular electron transfer (EET) pathways, such as those in the bacterium Shewanella oneidensis, interface cellular metabolism with a variety of redox-driven applications. However, designer control over EET flux in S. oneidensis has proven challenging because a functional understanding of its EET pathway proteins and their effect on engineering parametrizations (e.g., response curves, dynamic range) is generally lacking. To address this, we systematically altered transcription and translation of single genes encoding parts of the primary EET pathway of S. oneidensis, CymA/MtrCAB, and examined how expression differences affected model-fitted parameters for Fe(III) reduction kinetics. Using a suite of plasmid-based inducible circuits maintained by appropriate S. oneidensis knockout strains, we pinpointed construct/strain pairings that expressed cymA, mtrA, and mtrC with maximal dynamic range of Fe(III) reduction rate. These optimized EET gene constructs were employed to create Buffer and NOT gate architectures that predictably turn on and turn off EET flux, respectively, in response to isopropyl β-D-1-thiogalactopyranoside (IPTG). Furthermore, we found that response functions generated by these logic gates (i.e., EET activity vs inducer concentration) were comparable to those generated by conventional synthetic biology circuits, where fluorescent reporters are the output. Our results provide insight on programming EET activity with transcriptional logic gates and suggest that previously developed transcriptional circuitry can be adapted to predictably control EET flux.
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Affiliation(s)
- Christopher M. Dundas
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - David J.F. Walker
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712, United States
| | - Benjamin K. Keitz
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
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79
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A Hybrid Extracellular Electron Transfer Pathway Enhances the Survival of Vibrio natriegens. Appl Environ Microbiol 2020; 86:AEM.01253-20. [PMID: 32737131 DOI: 10.1128/aem.01253-20] [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: 05/26/2020] [Accepted: 07/28/2020] [Indexed: 02/06/2023] Open
Abstract
Vibrio natriegens is the fastest-growing microorganism discovered to date, making it a useful model for biotechnology and basic research. While it is recognized for its rapid aerobic metabolism, less is known about anaerobic adaptations in V. natriegens or how the organism survives when oxygen is limited. Here, we describe and characterize extracellular electron transfer (EET) in V. natriegens, a metabolism that requires movement of electrons across protective cellular barriers to reach the extracellular space. V. natriegens performs extracellular electron transfer under fermentative conditions with gluconate, glucosamine, and pyruvate. We characterized a pathway in V. natriegens that requires CymA, PdsA, and MtrCAB for Fe(III) citrate and Fe(III) oxide reduction, which represents a hybrid of strategies previously discovered in Shewanella and Aeromonas Expression of these V. natriegens genes functionally complemented Shewanella oneidensis mutants. Phylogenetic analysis of the inner membrane quinol dehydrogenases CymA and NapC in gammaproteobacteria suggests that CymA from Shewanella diverged from Vibrionaceae CymA and NapC. Analysis of sequenced Vibrionaceae revealed that the genetic potential to perform EET is conserved in some members of the Harveyi and Vulnificus clades but is more variable in other clades. We provide evidence that EET enhances anaerobic survival of V. natriegens, which may be the primary physiological function for EET in Vibrionaceae IMPORTANCE Bacteria from the genus Vibrio occupy a variety of marine and brackish niches with fluctuating nutrient and energy sources. When oxygen is limited, fermentation or alternative respiration pathways must be used to conserve energy. In sedimentary environments, insoluble oxide minerals (primarily iron and manganese) are able to serve as electron acceptors for anaerobic respiration by microorganisms capable of extracellular electron transfer, a metabolism that enables the use of these insoluble substrates. Here, we identify the mechanism for extracellular electron transfer in Vibrio natriegens, which uses a combination of strategies previously identified in Shewanella and Aeromonas We show that extracellular electron transfer enhanced survival of V. natriegens under fermentative conditions, which may be a generalized strategy among Vibrio spp. predicted to have this metabolism.
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80
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Roy S, Xie O, Dorval Courchesne N. Challenges in engineering conductive protein fibres: Disentangling the knowledge. CAN J CHEM ENG 2020. [DOI: 10.1002/cjce.23836] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Sophia Roy
- Department of Chemical Engineering McGill University Montréal Québec Canada
| | - Oliver Xie
- Department of Chemical Engineering McGill University Montréal Québec Canada
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81
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Pirbadian S, Chavez MS, El-Naggar MY. Spatiotemporal mapping of bacterial membrane potential responses to extracellular electron transfer. Proc Natl Acad Sci U S A 2020; 117:20171-20179. [PMID: 32747561 PMCID: PMC7443868 DOI: 10.1073/pnas.2000802117] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Extracellular electron transfer (EET) allows microorganisms to gain energy by linking intracellular reactions to external surfaces ranging from natural minerals to the electrodes of bioelectrochemical renewable energy technologies. In the past two decades, electrochemical techniques have been used to investigate EET in a wide range of microbes, with emphasis on dissimilatory metal-reducing bacteria, such as Shewanella oneidensis MR-1, as model organisms. However, due to the typically bulk nature of these techniques, they are unable to reveal the subpopulation variation in EET or link the observed electrochemical currents to energy gain by individual cells, thus overlooking the potentially complex spatial patterns of activity in bioelectrochemical systems. Here, to address these limitations, we use the cell membrane potential as a bioenergetic indicator of EET by S. oneidensis MR-1 cells. Using a fluorescent membrane potential indicator during in vivo single-cell-level fluorescence microscopy in a bioelectrochemical reactor, we demonstrate that membrane potential strongly correlates with EET. Increasing electrode potential and associated EET current leads to more negative membrane potential. This EET-induced membrane hyperpolarization is spatially limited to cells in contact with the electrode and within a near-electrode zone (<30 μm) where the hyperpolarization decays with increasing cell-electrode distance. The high spatial and temporal resolution of the reported technique can be used to study the single-cell-level dynamics of EET not only on electrode surfaces, but also during respiration of other solid-phase electron acceptors.
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Affiliation(s)
- Sahand Pirbadian
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089
| | - Marko S Chavez
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089
| | - Mohamed Y El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089;
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089
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82
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Li S, Niu Y, Chen H, He P. Complete genome sequence of an Arctic Ocean bacterium Shewanella sp. Arc9-LZ with capacity of synthesizing silver nanoparticles in darkness. Mar Genomics 2020; 56:100808. [PMID: 32778401 DOI: 10.1016/j.margen.2020.100808] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/15/2020] [Accepted: 07/22/2020] [Indexed: 11/15/2022]
Abstract
Shewanella sp. Arc9-LZ is a bacterium capable of synthesizing silver nanoparticles in darkness. It was isolated from the marine sediment from the Arctic Ocean (158°01'12"W; 84°28'38"N) collected during the 9th Chinese National Arctic Expedition in 2018. Here, we describe the complete genome of Shewanella sp. Arc9-LZ. The complete genome of Shewanella sp. Arc9-LZ is composed of a circular chromosome of 4,911,031 bp with G + C content of 41.61 mol%. The genome encodes 4040 protein-coding genes (CDSs), 104 tRNAs, and 35 rRNAs. The rRNAs contain 14 copies of 5S rRNA gene, 11 copies of 16S rRNA gene, and 10 copies of 23S rRNA gene. Based on the KEGG, COG, NR, Swiss-Prot, TCDB, and CAZy analysis, a total of 64 genes belonging to 9 kinds are related to the AgNPs synthesis. These genes are involeved in the synthesis of riboflavin, b-type cytochrome, c-type cytochrome, coenzyme Q, NADPH dehydrogenase, cytochrome c reductase, cytochrome c oxidase, nitroreductase, and nitrate reductase.
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Affiliation(s)
- Shuang Li
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao 266061, China; Key Laboratory of Natural Products of Qingdao, Qingdao 266061, China
| | - Yuanyuan Niu
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao 266061, China; Key Laboratory of Natural Products of Qingdao, Qingdao 266061, China
| | - Hao Chen
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao 266061, China; Key Laboratory of Natural Products of Qingdao, Qingdao 266061, China
| | - Peiqing He
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao 266061, China; Key Laboratory of Natural Products of Qingdao, Qingdao 266061, China.
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83
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Méhes G, Roy A, Strakosas X, Berggren M, Stavrinidou E, Simon DT. Organic Microbial Electrochemical Transistor Monitoring Extracellular Electron Transfer. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2000641. [PMID: 32775155 PMCID: PMC7404149 DOI: 10.1002/advs.202000641] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/08/2020] [Indexed: 05/11/2023]
Abstract
Extracellular electron transfer (EET) denotes the process of microbial respiration with electron transfer to extracellular acceptors and has been exploited in a range of microbial electrochemical systems (MESs). To further understand EET and to optimize the performance of MESs, a better understanding of the dynamics at the microscale is needed. However, the real-time monitoring of EET at high spatiotemporal resolution would require sophisticated signal amplification. To amplify local EET signals, a miniaturized bioelectronic device, the so-called organic microbial electrochemical transistor (OMECT), is developed, which includes Shewanella oneidensis MR-1 integrated onto organic electrochemical transistors comprising poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) combined with poly(vinyl alcohol) (PVA). Bacteria are attached to the gate of the transistor by a chronoamperometric method and the successful attachment is confirmed by fluorescence microscopy. Monitoring EET with the OMECT configuration is achieved due to the inherent amplification of the transistor, revealing fast time-responses to lactate. The limits of detection when using microfabricated gates as charge collectors are also investigated. The work is a first step toward understanding and monitoring EET in highly confined spaces via microfabricated organic electronic devices, and it can be of importance to study exoelectrogens in microenvironments, such as those of the human microbiome.
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Affiliation(s)
- Gábor Méhes
- Laboratory of Organic ElectronicsDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
| | - Arghyamalya Roy
- Laboratory of Organic ElectronicsDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
| | - Xenofon Strakosas
- Laboratory of Organic ElectronicsDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
| | - Magnus Berggren
- Laboratory of Organic ElectronicsDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
- Wallenberg Wood Science CenterDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
| | - Eleni Stavrinidou
- Laboratory of Organic ElectronicsDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
- Wallenberg Wood Science CenterDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
| | - Daniel T. Simon
- Laboratory of Organic ElectronicsDepartment of Science and TechnologyLinköping UniversityNorrköping60174Sweden
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84
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Wang G, Han N, Liu L, Ke Z, Li B, Chen G. Molecular density regulating electron transfer efficiency of S. oneidensis MR-1 mediated roxarsone biotransformation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 262:114370. [PMID: 32443212 DOI: 10.1016/j.envpol.2020.114370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/17/2020] [Accepted: 03/12/2020] [Indexed: 06/11/2023]
Abstract
Efficient extracellular electron transport is a key for sufficient bioremediation of organoarsenic pollutants such as 4-hydroxy-3-nitrobenzenearsonic acid (roxarsone). The related apparent kinetics characteristics are essential for engineering practice of bioremediation activities and for full understanding the environmental fate of roxarsone, yet remains poorly understood. We report, to our knowledge, the first study of the electron transfer characteristics between roxarsone and participating S. oneidensis MR-1. The electron transfer rate during roxarsone biotransformation was estimated up to 3.1 × 106 electrons/cell/s, with its value being clearly associated with the apparent roxarsone concentration. Lowing roxarsone concentration extended the average separation distance between cells and neighboring roxarsone molecules and thereby augmented electric resistance as well as extended cell movement for foraging, thus reduced electron transfer rate. In addition, the presence of roxarsone significantly stimulated population growth of S. oneidensis MR-1 with nearly doubled maximum specific growth rate, albeit with clearly increased lag time, as compared with that of none-roxarsone scenario. These findings provide, at the first time, basic biostoichiometry of S. oneidensis MR-1 induced roxarsone biotransformation, which may shed lights for full understanding of roxarsone transformation process in waste treatment systems that are necessary for engineering practice and/or environmental risks assessment.
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Affiliation(s)
- Gang Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Neng Han
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Li Liu
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Zhengchen Ke
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Baoguo Li
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Guowei Chen
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China.
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85
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Wu Y, Luo X, Qin B, Li F, Häggblom MM, Liu T. Enhanced Current Production by Exogenous Electron Mediators via Synergy of Promoting Biofilm Formation and the Electron Shuttling Process. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:7217-7225. [PMID: 32352288 DOI: 10.1021/acs.est.0c00141] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Exogenous electron mediators (EMs) can facilitate extracellular electron transfer (EET) via electron shuttling processes, but it is still unclear whether and how biofilm formation is affected by the presence of EMs. Here, the impacts of EMs on EET and biofilm formation were investigated in bioelectrochemical systems (BESs) with Shewanella oneidensis MR-1, and the results showed that the presence of five different EMs led to high density current production. All the EMs substantially promoted biofilm formation with 15-36 times higher total biofilm DNA with EMs than without EMs, and they also increased the production of extracellular polymeric substances, which was favorable for biofilm formation. The current decreased substantially after removing EMs from the medium or by replacing electrodes without biofilm, suggesting that both biofilm and EMs are required for high density current production. EET-related gene expression was upregulated with EMs, resulting in the high flux of cell electron output. A synergistic mechanism was proposed: EMs in suspension were quickly reduced by the cells and reoxidized rapidly by the electrode, resulting in a microenvironment with sufficient oxidized EMs for biofilm formation, and thus, besides the well-known electron shuttling process, the EM-induced high biofilm formation and high Mtr gene expression could jointly contribute to the EET and subsequently produce a high density current. This study provides a new insight into EM-enhanced current production via regulating the biofilm formation and EET-related gene expression.
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Affiliation(s)
- Yundang Wu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science and Technology, Guangdong Academy of Sciences, Guangzhou 510650, P. R. China
| | - Xiaobo Luo
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science and Technology, Guangdong Academy of Sciences, Guangzhou 510650, P. R. China
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, PR China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Baoli Qin
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China
| | - Fangbai Li
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science and Technology, Guangdong Academy of Sciences, Guangzhou 510650, P. R. China
| | - Max M Häggblom
- Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Tongxu Liu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science and Technology, Guangdong Academy of Sciences, Guangzhou 510650, P. R. China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
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86
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Su L, Fukushima T, Ajo-Franklin CM. A hybrid cyt c maturation system enhances the bioelectrical performance of engineered Escherichia coli by improving the rate-limiting step. Biosens Bioelectron 2020; 165:112312. [PMID: 32729471 DOI: 10.1016/j.bios.2020.112312] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 12/26/2022]
Abstract
Bioelectronic devices can use electron flux to enable communication between biotic components and abiotic electrodes. We have modified Escherichia coli to electrically interact with electrodes by expressing the cytochrome c from Shewanella oneidensis MR-1. However, we observe inefficient electrical performance, which we hypothesize is due to the limited compatibility of the E. coli cytochrome c maturation (Ccm) systems with MR-1 cytochrome c. Here we test whether the bioelectronic performance of E. coli can be improved by constructing hybrid Ccm systems containing protein domains from both E. coli and S. oneidensis MR-1. The hybrid CcmH increased cytochrome c expression by increasing the abundance of CymA 60%, while only slightly changing the abundance of the other cytochromes c. Electrochemical measurements showed that the overall current from the hybrid ccm strain increased 121% relative to the wildtype ccm strain, with an electron flux per cell of 12.3 ± 0.3 fA·cell-1. Additionally, the hybrid ccm strain doubled its electrical response with the addition of exogenous flavin, and quantitative analysis of this demonstrates CymA is the rate-limiting step in this electron conduit. These results demonstrate that this hybrid Ccm system can enhance the bioelectrical performance of the cyt c expressing E. coli, allowing the construction of more efficient bioelectronic devices.
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Affiliation(s)
- Lin Su
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210018, China; Department of BioSciences, Rice University, Houston, TX, 77005, USA; Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Tatsuya Fukushima
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Caroline M Ajo-Franklin
- Department of BioSciences, Rice University, Houston, TX, 77005, USA; Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA; Molecular Biophysics and Integrated Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA; Institute for Biosciences and Bioengineering, Rice University, Houston, TX, 77005, USA.
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87
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Vettese GF, Morris K, Natrajan LS, Shaw S, Vitova T, Galanzew J, Jones DL, Lloyd JR. Multiple Lines of Evidence Identify U(V) as a Key Intermediate during U(VI) Reduction by Shewanella oneidensis MR1. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:2268-2276. [PMID: 31934763 DOI: 10.1021/acs.est.9b05285] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
As the dominant radionuclide by mass in many radioactive wastes, the control of uranium mobility in contaminated environments is of high concern. U speciation can be governed by microbial interactions, whereby metal-reducing bacteria are able to reduce soluble U(VI) to insoluble U(IV), providing a method for removal of U from contaminated groundwater. Although microbial U(VI) reduction is widely reported, the mechanism(s) for the transformation of U(VI) to relatively insoluble U(IV) phases are poorly understood. By combining a suite of analyses, including luminescence, U M4-edge high-energy resolved fluorescence detection-X-ray absorption near-edge structure (XANES), and U L3-edge XANES/extended X-ray absorption fine structure, we show that the microbial reduction of U(VI) by the model Fe(III)-reducing bacterium, Shewanella oneidensis MR1, proceeds via a single electron transfer to form a pentavalent U(V) intermediate which disproportionates to form U(VI) and U(IV). Furthermore, we have identified significant U(V) present in post reduction solid phases, implying that U(V) may be stabilized for up to 120.5 h.
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Affiliation(s)
- Gianni F Vettese
- Williamson Research Centre for Molecular Environmental Science and Research Centre for Radwaste Disposal, Department of Earth and Environmental Science, School of Natural Sciences , The University of Manchester , Oxford Road , Manchester M13 9PL , England
| | - Katherine Morris
- Williamson Research Centre for Molecular Environmental Science and Research Centre for Radwaste Disposal, Department of Earth and Environmental Science, School of Natural Sciences , The University of Manchester , Oxford Road , Manchester M13 9PL , England
| | - Louise S Natrajan
- Centre for Radiochemistry Research, Department of Chemistry, School of Natural Sciences , The University of Manchester , Oxford Road , Manchester M13 9PL , England
| | - Samuel Shaw
- Williamson Research Centre for Molecular Environmental Science and Research Centre for Radwaste Disposal, Department of Earth and Environmental Science, School of Natural Sciences , The University of Manchester , Oxford Road , Manchester M13 9PL , England
| | - Tonya Vitova
- Institute for Nuclear Waste Disposal (INE) , Karlsruhe Institute of Technology , Karlsruhe 76131 , Germany
| | - Jurij Galanzew
- Institute for Nuclear Waste Disposal (INE) , Karlsruhe Institute of Technology , Karlsruhe 76131 , Germany
| | - Debbie L Jones
- College of Environmental Sciences and Engineering , Bangor University , Bangor LL57 2DG , U.K
| | - Jonathan R Lloyd
- Williamson Research Centre for Molecular Environmental Science and Research Centre for Radwaste Disposal, Department of Earth and Environmental Science, School of Natural Sciences , The University of Manchester , Oxford Road , Manchester M13 9PL , England
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88
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Chen J, Wang Y. Genetic determinants of Salmonella enterica critical for attachment and biofilm formation. Int J Food Microbiol 2020; 320:108524. [PMID: 32000116 DOI: 10.1016/j.ijfoodmicro.2020.108524] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 12/21/2022]
Abstract
Salmonella is a bacterial pathogen frequently involved in human gastrointestinal infections including those associated with low-moisture foods such as dehydrated food powders/spices, vegetable seeds, and tree nuts. The survival/persistence of Salmonella on low moisture foods and in dry environments is enhanced by its ability in developing biofilms. This study was undertaken to identify the genetic determinants critical for Salmonella attachment and biofilm formation. E. coli SM10 lambda pir, with a kanamycin resistant marker on mini-Tn10 (mini-Tn10:lacZ:kanr), an ampicillin resistant marker on the mini-Tn10-bearing suicidal plasmid pLBT and a streptomycin sensitive marker on the SM10 chromosome, was used as a donor (ampr, kanr, streps), and three Salmonella strains (amps, kans, strepr) were used as recipients in a transposon mutagenesis study. The donor and each recipient were co-incubated overnight on tryptic soy agar at 37 °C, and mutant colonies (amps, kanr, strepr) were subsequently selected. A single-banded degenerate PCR product, amplified from each mutant genome using oligonucleotide primers derived from the end of min-Tn10 and restriction enzyme EcoR I- or Pst I-recognizing sequence, were analyzed using the Sanger sequencing technology. Acquired DNA sequences were compared to those deposited in the Genbank using BLAST search. Cells of Salmonella mutants accumulated either significantly more or less (P < 0.05) biofilms than their parent cells on polystyrene surface. Sequence analysis of degenerate PCR products revealed that the mini-Tn10 from pLBT had inserted into the cdg, trx, fadI or rxt on Salmonella chromosomes. Results of the research will likely help strategize future antimicrobial intervention for control of pathogen attachment and biofilm formation.
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Affiliation(s)
- Jinru Chen
- Department of Food Science and Technology, The University of Georgia, 1109 Experiment St., Griffin, GA 30223-1797, USA.
| | - Yin Wang
- Department of Food Science and Technology, The University of Georgia, 1109 Experiment St., Griffin, GA 30223-1797, USA
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89
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Yee MO, Rotaru AE. Extracellular electron uptake in Methanosarcinales is independent of multiheme c-type cytochromes. Sci Rep 2020; 10:372. [PMID: 31941946 PMCID: PMC6962339 DOI: 10.1038/s41598-019-57206-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 12/23/2019] [Indexed: 11/14/2022] Open
Abstract
The co-occurrence of Geobacter and Methanosarcinales is often used as a proxy for the manifestation of direct interspecies electron transfer (DIET) in the environment. Here we tested eleven new co-culture combinations between methanogens and electrogens. Previously, only the most electrogenic Geobacter paired by DIET with Methanosarcinales methanogens, namely G. metallireducens and G. hydrogenophilus. Here we provide additional support, and show that five additional Methanosarcinales paired with G. metallireducens, while a strict hydrogenotroph could not. We also show that G. hydrogenophilus, which is incapable to grow with a strict hydrogenotrophic methanogen, could pair with a strict non-hydrogenotrophic Methanosarcinales. Likewise, an electrogen outside the Geobacter cluster (Rhodoferrax ferrireducens) paired with Methanosarcinales but not with strict hydrogenotrophic methanogens. The ability to interact with electrogens appears to be conserved among Methanosarcinales, the only methanogens with c-type cytochromes, including multihemes (MHC). Nonetheless, MHC, which are often linked to extracellular electron transfer, were neither unique nor universal to Methanosarcinales and only two of seven Methanosarcinales tested had MHC. Of these two, one strain had an MHC-deletion knockout available, which we hereby show is still capable to retrieve extracellular electrons from G. metallireducens or an electrode suggesting an MHC-independent strategy for extracellular electron uptake.
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Affiliation(s)
- Mon Oo Yee
- Nordcee, Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Amelia-Elena Rotaru
- Nordcee, Department of Biology, University of Southern Denmark, Odense, Denmark.
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90
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Dietrich HM, Edel M, Bursac T, Meier M, Sturm-Richter K, Gescher J. Soluble versions of outer membrane cytochromes function as exporters for heterologously produced cargo proteins. Microb Cell Fact 2019; 18:216. [PMID: 31870378 PMCID: PMC6929479 DOI: 10.1186/s12934-019-1270-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 12/13/2019] [Indexed: 11/13/2022] Open
Abstract
This study reveals that it is possible to secrete truncated versions of outer membrane cytochromes into the culture supernatant and that these proteins can provide a basis for the export of heterologously produced proteins. Different soluble and truncated versions of the outer membrane cytochrome MtrF were analyzed for their suitability to be secreted. A protein version with a very short truncation of the N-terminus to remove the recognition sequence for the addition of a lipid anchor is secreted efficiently to the culture supernatant, and moreover this protein could be further truncated by a deletion of 160 amino acid and still is detectable in the supernatant. By coupling a cellulase to this soluble outer membrane cytochrome, the export efficiency was measured by means of relative cellulase activity. We conclude that outer membrane cytochromes of S. oneidensis can be applied as transporters for the export of target proteins into the medium using the type II secretion pathway.
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Affiliation(s)
- Helge M Dietrich
- Department of Molecular Microbiology and Bioenergetics, Goethe University, Frankfurt, Germany
| | - Miriam Edel
- Department of Applied Biology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Thea Bursac
- Department of Applied Biology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Manfred Meier
- Institute for Biological Interfaces, Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
| | - Katrin Sturm-Richter
- Department of Applied Biology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Johannes Gescher
- Department of Applied Biology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
- Institute for Biological Interfaces, Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany.
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91
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Suravaram SK, Smith DK, Parkin A, Chechik V. Conductive Gels Based on Modified Agarose Embedded with Gold Nanoparticles and their Application as a Conducting Support for
Shewanella Oneidensis
MR‐1. ChemElectroChem 2019. [DOI: 10.1002/celc.201901618] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - David K. Smith
- Department of ChemistryUniversity of York Heslington York YO10 5DD UK
| | - Alison Parkin
- Department of ChemistryUniversity of York Heslington York YO10 5DD UK
| | - Victor Chechik
- Department of ChemistryUniversity of York Heslington York YO10 5DD UK
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92
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Cheng L, Min D, Liu DF, Li WW, Yu HQ. Sensing and Approaching Toxic Arsenate by Shewanella putrefaciens CN-32. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:14604-14611. [PMID: 31747260 DOI: 10.1021/acs.est.9b05890] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Although arsenic at a high concentration imposes strong selective pressure on microbes, various microbes have been found to grow in As-rich environments. So far, little is known about how microbes can sense and move toward arsenate in the environment, and the underlying molecular mechanisms have not been revealed. Here, we report the chemotaxis response toward arsenate (As(V)) by Shewanella putrefaciens CN-32, a model dissimilatory metal-reducing bacterium (DMRB), and elucidate the mechanisms. We find that S. putrefaciens CN-32 exhibits a chemotactic behavior toward As(V) and diverse electron acceptors. To sense As(V), S. putrefaciens CN-32 requires functional arsenate respiratory reductase but does not depend on its metal-reducing-like respiratory pathway. We observe that such a sense is governed by an energy taxis mechanism and mediated by several methyl-accepting chemotaxis proteins (MCPs), rather than a specific MCP. Moreover, we reveal that the chemotactic signal transduction pathway is conserved in Shewanella, and histidine kinase and flagella-mediated motility are essential for taxis toward As(V). This work reverses the conventional view about arsenic as a chemotactic inhibitor to microbes by revealing the positive chemotaxis of Shewanella to As(V).
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93
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Microbial reduction of metal-organic frameworks enables synergistic chromium removal. Nat Commun 2019; 10:5212. [PMID: 31740677 PMCID: PMC6861306 DOI: 10.1038/s41467-019-13219-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 10/28/2019] [Indexed: 11/10/2022] Open
Abstract
Redox interactions between electroactive bacteria and inorganic materials underpin many emerging technologies, but commonly used materials (e.g., metal oxides) suffer from limited tunability and can be challenging to characterize. In contrast, metal-organic frameworks exhibit well-defined structures, large surface areas, and extensive chemical tunability, but their utility as microbial substrates has not been examined. Here, we report that metal-organic frameworks can support the growth of the metal-respiring bacterium Shewanella oneidensis, specifically through the reduction of Fe(III). In a practical application, we show that cultures containing S. oneidensis and reduced metal-organic frameworks can remediate lethal concentrations of Cr(VI) over multiple cycles, and that pollutant removal exceeds the performance of either component in isolation or bio-reduced iron oxides. Our results demonstrate that frameworks can serve as growth substrates and suggest that they may offer an alternative to metal oxides in applications seeking to combine the advantages of bacterial metabolism and synthetic materials. Interactions between electroactive bacteria and metal oxides are used for bioremediation. Here, the authors report on the application of Fe(III)-containing metal organic frameworks as substrates for bacterial growth which allow for remediation of lethal levels of chromium with high efficacy over several cycles.
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94
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Mitchell SL, Hudson-Smith NV, Cahill MS, Reynolds BN, Frand SD, Green CM, Wang C, Hang MN, Hernandez RT, Hamers RJ, Feng ZV, Haynes CL, Carlson EE. Chronic exposure to complex metal oxide nanoparticles elicits rapid resistance in Shewanella oneidensis MR-1. Chem Sci 2019; 10:9768-9781. [PMID: 32055346 PMCID: PMC6993611 DOI: 10.1039/c9sc01942a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 08/29/2019] [Indexed: 12/20/2022] Open
Abstract
Engineered nanoparticles are incorporated into numerous emerging technologies because of their unique physical and chemical properties. Many of these properties facilitate novel interactions, including both intentional and accidental effects on biological systems. Silver-containing particles are widely used as antimicrobial agents and recent evidence indicates that bacteria rapidly become resistant to these nanoparticles. Much less studied is the chronic exposure of bacteria to particles that were not designed to interact with microorganisms. For example, previous work has demonstrated that the lithium intercalated battery cathode nanosheet, nickel manganese cobalt oxide (NMC), is cytotoxic and causes a significant delay in growth of Shewanella oneidensis MR-1 upon acute exposure. Here, we report that S. oneidensis MR-1 rapidly adapts to chronic NMC exposure and is subsequently able to survive in much higher concentrations of these particles, providing the first evidence of permanent bacterial resistance following exposure to nanoparticles that were not intended as antibacterial agents. We also found that when NMC-adapted bacteria were subjected to only the metal ions released from this material, their specific growth rates were higher than when exposed to the nanoparticle. As such, we provide here the first demonstration of bacterial resistance to complex metal oxide nanoparticles with an adaptation mechanism that cannot be fully explained by multi-metal adaptation. Importantly, this adaptation persists even after the organism has been grown in pristine media for multiple generations, indicating that S. oneidensis MR-1 has developed permanent resistance to NMC.
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Affiliation(s)
- Stephanie L Mitchell
- Department of Chemistry , University of Minnesota , 207 Pleasant St. SE , Minneapolis , MN 55455 , USA .
| | - Natalie V Hudson-Smith
- Department of Chemistry , University of Minnesota , 207 Pleasant St. SE , Minneapolis , MN 55455 , USA .
| | - Meghan S Cahill
- Department of Chemistry , University of Minnesota , 207 Pleasant St. SE , Minneapolis , MN 55455 , USA .
| | - Benjamin N Reynolds
- Department of Biochemistry, Molecular Biology, and Biophysics , University of Minnesota , 321 Church Street SE , Minneapolis , Minnesota 55454 , USA
| | - Seth D Frand
- Chemistry Department , Augsburg University , 2211 Riverside Ave , Minneapolis , MN 55454 , USA
| | - Curtis M Green
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , WI 53706 , USA
| | - Chenyu Wang
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , WI 53706 , USA
| | - Mimi N Hang
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , WI 53706 , USA
| | - Rodrigo Tapia Hernandez
- Chemistry Department , Augsburg University , 2211 Riverside Ave , Minneapolis , MN 55454 , USA
| | - Robert J Hamers
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , WI 53706 , USA
| | - Z Vivian Feng
- Chemistry Department , Augsburg University , 2211 Riverside Ave , Minneapolis , MN 55454 , USA
| | - Christy L Haynes
- Department of Chemistry , University of Minnesota , 207 Pleasant St. SE , Minneapolis , MN 55455 , USA .
| | - Erin E Carlson
- Department of Chemistry , University of Minnesota , 207 Pleasant St. SE , Minneapolis , MN 55455 , USA .
- Department of Biochemistry, Molecular Biology, and Biophysics , University of Minnesota , 321 Church Street SE , Minneapolis , Minnesota 55454 , USA
- Department of Medicinal Chemistry , University of Minnesota , 208 Harvard Street SE , Minneapolis , 55454 , USA
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95
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Mishra S, Pirbadian S, Mondal AK, El-Naggar MY, Naaman R. Spin-Dependent Electron Transport through Bacterial Cell Surface Multiheme Electron Conduits. J Am Chem Soc 2019; 141:19198-19202. [DOI: 10.1021/jacs.9b09262] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Suryakant Mishra
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sahand Pirbadian
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089, United States
| | - Amit Kumar Mondal
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Mohamed Y. El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089, United States
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
- Department of Biological Sciences, University of Southern California, Los Angeles, California 91030, United States
| | - Ron Naaman
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel
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96
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Strategies for improving the electroactivity and specific metabolic functionality of microorganisms for various microbial electrochemical technologies. Biotechnol Adv 2019; 39:107468. [PMID: 31707076 DOI: 10.1016/j.biotechadv.2019.107468] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 11/02/2019] [Accepted: 11/04/2019] [Indexed: 01/31/2023]
Abstract
Electroactive microorganisms, which possess extracellular electron transfer (EET) capabilities, are the basis of microbial electrochemical technologies (METs) such as microbial fuel and electrolysis cells. These are considered for several applications ranging from the energy-efficient treatment of waste streams to the production of value-added chemicals and fuels, bioremediation, and biosensing. Various aspects related to the microorganisms, electrodes, separators, reactor design, and operational or process parameters influence the overall functioning of METs. The most fundamental and critical performance-determining factor is, however, the microorganism-electrode interactions. Modification of the electrode surfaces and microorganisms for optimizing their interactions has therefore been the major MET research focus area over the last decade. In the case of microorganisms, primarily their EET mechanisms and efficiencies along with the biofilm formation capabilities, collectively considered as microbial electroactivity, affect their interactions with the electrodes. In addition to electroactivity, the specific metabolic or biochemical functionality of microorganisms is equally crucial to the target MET application. In this article, we present the major strategies that are used to enhance the electroactivity and specific functionality of microorganisms pertaining to both anodic and cathodic processes of METs. These include simple physical methods based on the use of heat and magnetic field along with chemical, electrochemical, and growth media amendment approaches to the complex procedure-based microbial bioaugmentation, co-culture, and cell immobilization or entrapment, and advanced toolkit-based biofilm engineering, genetic modifications, and synthetic biology strategies. We further discuss the applicability and limitations of these strategies and possible future research directions for advancing the highly promising microbial electrochemistry-driven biotechnology.
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97
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Gupta D, Sutherland MC, Rengasamy K, Meacham JM, Kranz RG, Bose A. Photoferrotrophs Produce a PioAB Electron Conduit for Extracellular Electron Uptake. mBio 2019; 10:e02668-19. [PMID: 31690680 PMCID: PMC6831781 DOI: 10.1128/mbio.02668-19] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 11/20/2022] Open
Abstract
Photoferrotrophy is a form of anoxygenic photosynthesis whereby bacteria utilize soluble or insoluble forms of ferrous iron as an electron donor to fix carbon dioxide using light energy. They can also use poised electrodes as their electron donor via phototrophic extracellular electron uptake (phototrophic EEU). The electron uptake mechanisms underlying these processes are not well understood. Using Rhodopseudomonas palustris TIE-1 as a model, we show that a single periplasmic decaheme cytochrome c, PioA, and an outer membrane porin, PioB, form a complex allowing extracellular electron uptake across the outer membrane from both soluble iron and poised electrodes. We observe that PioA undergoes postsecretory proteolysis of its N terminus to produce a shorter heme-attached PioA (holo-PioAC, where PioAC represents the C terminus of PioA), which can exist both freely in the periplasm and in a complex with PioB. The extended N-terminal peptide controls heme attachment, and its processing is required to produce wild-type levels of holo-PioAC and holo-PioACB complex. It is also conserved in PioA homologs from other phototrophs. The presence of PioAB in these organisms correlate with their ability to perform photoferrotrophy and phototrophic EEU.IMPORTANCE Some anoxygenic phototrophs use soluble iron, insoluble iron minerals (such as rust), or their proxies (poised electrodes) as electron donors for photosynthesis. However, the underlying electron uptake mechanisms are not well established. Here, we show that these phototrophs use a protein complex made of an outer membrane porin and a periplasmic decaheme cytochrome (electron transfer protein) to harvest electrons from both soluble iron and poised electrodes. This complex has two unique characteristics: (i) it lacks an extracellular cytochrome c, and (ii) the periplasmic decaheme cytochrome c undergoes proteolytic cleavage to produce a functional electron transfer protein. These characteristics are conserved in phototrophs harboring homologous proteins.
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Affiliation(s)
- Dinesh Gupta
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Molly C Sutherland
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | | | - J Mark Meacham
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, Missouri, USA
- Institute of Materials Science and Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Robert G Kranz
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Arpita Bose
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
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98
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Hirose A, Kouzuma A, Watanabe K. Towards development of electrogenetics using electrochemically active bacteria. Biotechnol Adv 2019; 37:107351. [DOI: 10.1016/j.biotechadv.2019.02.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/09/2019] [Accepted: 02/15/2019] [Indexed: 12/20/2022]
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99
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Complete Genome Sequence of Raoultella electrica 1GB (DSM 102253 T), Isolated from Anodic Biofilms of a Glucose-Fed Microbial Fuel Cell. Microbiol Resour Announc 2019; 8:8/43/e00800-19. [PMID: 31649093 PMCID: PMC6813382 DOI: 10.1128/mra.00800-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The type strain Raoultella electrica 1GB (DSM 102253T) was isolated from anodic biofilms of glucose-fed microbial fuel cells. The fully assembled, closed, circular 5.27-Mb genome and corresponding 0.52-Mb plasmid DNA sequences were elucidated. Potential electron transfer and pathogenicity mechanisms were deduced. The type strain Raoultella electrica 1GB (DSM 102253T) was isolated from anodic biofilms of glucose-fed microbial fuel cells. The fully assembled, closed, circular 5.27-Mb genome and corresponding 0.52-Mb plasmid DNA sequences were elucidated. Potential electron transfer and pathogenicity mechanisms were deduced.
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100
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NADH dehydrogenases Nuo and Nqr1 contribute to extracellular electron transfer by Shewanella oneidensis MR-1 in bioelectrochemical systems. Sci Rep 2019; 9:14959. [PMID: 31628378 PMCID: PMC6802487 DOI: 10.1038/s41598-019-51452-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 09/28/2019] [Indexed: 11/22/2022] Open
Abstract
Shewanella oneidensis MR-1 is quickly becoming a synthetic biology workhorse for bioelectrochemical technologies due to a high level of understanding of its interaction with electrodes. Transmembrane electron transfer via the Mtr pathway has been well characterized, however, the role of NADH dehydrogenases in feeding electrons to Mtr has been only minimally studied in S. oneidensis MR-1. Four NADH dehydrogenases are encoded in the genome, suggesting significant metabolic flexibility in oxidizing NADH under a variety of conditions. A strain lacking the two dehydrogenases essential for aerobic growth exhibited a severe growth defect with an anode (+0.4 VSHE) or Fe(III)-NTA as the terminal electron acceptor. Our study reveals that the same NADH dehydrogenase complexes are utilized under oxic conditions or with a high potential anode. Our study also supports the previously indicated importance of pyruvate dehydrogenase activity in producing NADH during anerobic lactate metabolism. Understanding the role of NADH in extracellular electron transfer may help improve biosensors and give insight into other applications for bioelectrochemical systems.
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