201
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Sun D, Call D, Wang A, Cheng S, Logan BE. Geobacter sp. SD-1 with enhanced electrochemical activity in high-salt concentration solutions. ENVIRONMENTAL MICROBIOLOGY REPORTS 2014; 6:723-729. [PMID: 25756125 DOI: 10.1111/1758-2229.12193] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An isolate, designated strain SD-1, was obtained from a biofilm dominated by Geobacter sulfurreducens in a microbial fuel cell. The electrochemical activity of strain SD-1 was compared with type strains, G. sulfurreducens PCA and Geobacter metallireducens GS-15, and a mixed culture in microbial electrolysis cells. SD-1 produced a maximum current density of 290 ± 29 A m−3 in a high-concentration phosphate buffer solution (PBS-H, 200 mM). This current density was significantly higher than that produced by the mixed culture (189 ± 44 A m−3) or the type strains (< 70 A m−3). In a highly saline water (SW; 50 mM PBS and 650 mM NaCl), current by SD-1 (158 ± 4 A m−3) was reduced by 28% compared with 50 mM PBS (220 ± 4 A m−3), but it was still higher than that of the mixed culture (147 ± 19 A m−3), and strains PCA and GS-15 did not produce any current. Electrochemical tests showed that the improved performance of SD-1 was due to its lower charge transfer resistance and more negative potentials produced at higher current densities. These results show that the electrochemical activity of SD-1 was significantly different than other Geobacter strains and mixed cultures in terms of its salt tolerance.
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202
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Yoho RA, Popat SC, Torres CI. Dynamic potential-dependent electron transport pathway shifts in anode biofilms of Geobacter sulfurreducens. CHEMSUSCHEM 2014; 7:3413-3419. [PMID: 25351488 DOI: 10.1002/cssc.201402589] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Revised: 08/31/2014] [Indexed: 06/04/2023]
Abstract
Biofilms of the anode-respiring bacterium Geobacter sulfurreducens (G. sulfurreducens) demonstrate dynamic potential-dependent changes between two electron transport pathways that are used selectively depending on the anode potential. Electrochemical impedance spectroscopy (EIS) measurements suggest that these pathways (both n=1), with midpoint potentials of -0.155 (± 0.005) and -0.095 (± 0.003) V versus standard hydrogen electrode, are not additive within the biofilm, but are preferentially used depending on the anode potential. Potential step voltammetry and cyclic voltammetry (CV) confirmed rapid changes between the two pathways in minutes when the anode potential is changed. We confirm that the electrochemical response observed in a slow-scan-rate CV (∼1 mV s(-1) ) is often composed of at least the two pathways characterized. Thus, beyond understanding the electron transport pathways in G. sulfurreducens, this study also has implications on the interpretation of previously collected and future potential-dependent datasets.
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Affiliation(s)
- Rachel A Yoho
- Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, 1001 S McAllister Avenue, Tempe, AZ 85287 (USA); School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287 (USA).
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203
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Improved current and power density with a micro-scale microbial fuel cell due to a small characteristic length. Biosens Bioelectron 2014; 61:587-92. [DOI: 10.1016/j.bios.2014.05.037] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 05/08/2014] [Accepted: 05/15/2014] [Indexed: 11/22/2022]
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204
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Miceli JF, Garcia-Peña I, Parameswaran P, Torres CI, Krajmalnik-Brown R. Combining microbial cultures for efficient production of electricity from butyrate in a microbial electrochemical cell. BIORESOURCE TECHNOLOGY 2014; 169:169-174. [PMID: 25048958 PMCID: PMC4284095 DOI: 10.1016/j.biortech.2014.06.090] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 06/06/2014] [Accepted: 06/25/2014] [Indexed: 05/25/2023]
Abstract
Butyrate is an important product of anaerobic fermentation; however, it is not directly used by characterized strains of the highly efficient anode respiring bacteria (ARB) Geobacter sulfurreducens in microbial electrochemical cells. By combining a butyrate-oxidizing community with a Geobacter rich culture, we generated a microbial community which outperformed many naturally derived communities found in the literature for current production from butyrate and rivaled the highest performing natural cultures in terms of current density (∼ 11A/m(2)) and Coulombic efficiency (∼ 70%). Microbial community analyses support the shift in the microbial community from one lacking efficient ARB in the marine hydrothermal vent community to a community consisting of ∼ 80% Geobacter in the anode biofilm. This demonstrates the successful production and adaptation of a novel microbial culture for generating electrical current from butyrate with high current density and high Coulombic efficiency, by combining two mixed microbial cultures containing complementing biochemical pathways.
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Affiliation(s)
- Joseph F Miceli
- Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA
| | - Ines Garcia-Peña
- Bioprocesses Department, Unidad Profesional Interdisciplinaria de Biotecnología, IPN P.O. Box 07340, Mexico City, Mexico
| | - Prathap Parameswaran
- Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA
| | - César I Torres
- Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA; Chemical Engineering Program, School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, USA.
| | - Rosa Krajmalnik-Brown
- Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA; School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA.
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205
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Geobacter anodireducens sp. nov., an exoelectrogenic microbe in bioelectrochemical systems. Int J Syst Evol Microbiol 2014; 64:3485-3491. [DOI: 10.1099/ijs.0.061598-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A previously isolated exoelectrogenic bacterium, strain SD-1T, was further characterized and identified as a representative of a novel species of the genus
Geobacter
. Strain SD-1T was Gram-negative, aerotolerant, anaerobic, non-spore-forming, non-fermentative and non-motile. Cells were short, curved rods (0.8–1.3 µm long and 0.3 µm in diameter). Growth of strain SD-1T was observed at 15–42 °C and pH 6.0–8.5, with optimal growth at 30–35 °C and pH 7. Analysis of 16S rRNA gene sequences indicated that the isolate was a member of the genus
Geobacter
, with the closest known relative being
Geobacter sulfurreducens
PCAT (98 % similarity). Similar to other members of the genus
Geobacter
, strain SD-1T used soluble or insoluble Fe(III) as the sole electron acceptor coupled with the oxidation of acetate. However, SD-1T could not reduce fumarate as an electron acceptor with acetate oxidization, which is an important physiological trait for
G. sulfurreducens
. Moreover, SD-1T could grow in media containing as much as 3 % NaCl, while
G. sulfurreducens
PCAT can tolerate just half this concentration, and this difference in salt tolerance was even more obvious when cultivated in bioelectrochemical systems. DNA–DNA hybridization analysis of strain SD-1T and its closest relative,
G. sulfurreducens
ATCC 51573T, showed a relatedness of 61.6 %. The DNA G+C content of strain SD-1T was 58.9 mol%. Thus, on the basis of these characteristics, strain SD-1T was not assigned to
G. sulfurreducens
, and was instead classified in the genus
Geobacter
as a representative of a novel species. The name Geobacter anodireducens sp. nov. is proposed, with the type strain SD-1T ( = CGMCC 1.12536T = KCTC 4672T).
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206
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Zhang H, Chen X, Braithwaite D, He Z. Phylogenetic and metagenomic analyses of substrate-dependent bacterial temporal dynamics in microbial fuel cells. PLoS One 2014; 9:e107460. [PMID: 25202990 PMCID: PMC4159341 DOI: 10.1371/journal.pone.0107460] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 08/12/2014] [Indexed: 12/25/2022] Open
Abstract
Understanding the microbial community structure and genetic potential of anode biofilms is key to improve extracellular electron transfers in microbial fuel cells. We investigated effect of substrate and temporal dynamics of anodic biofilm communities using phylogenetic and metagenomic approaches in parallel with electrochemical characterizations. The startup non-steady state anodic bacterial structures were compared for a simple substrate, acetate, and for a complex substrate, landfill leachate, using a single-chamber air-cathode microbial fuel cell. Principal coordinate analysis showed that distinct community structures were formed with each substrate type. The bacterial diversity measured as Shannon index decreased with time in acetate cycles, and was restored with the introduction of leachate. The change of diversity was accompanied by an opposite trend in the relative abundance of Geobacter-affiliated phylotypes, which were acclimated to over 40% of total Bacteria at the end of acetate-fed conditions then declined in the leachate cycles. The transition from acetate to leachate caused a decrease in output power density from 243±13 mW/m2 to 140±11 mW/m2, accompanied by a decrease in Coulombic electron recovery from 18±3% to 9±3%. The leachate cycles selected protein-degrading phylotypes within phylum Synergistetes. Metagenomic shotgun sequencing showed that leachate-fed communities had higher cell motility genes including bacterial chemotaxis and flagellar assembly, and increased gene abundance related to metal resistance, antibiotic resistance, and quorum sensing. These differentially represented genes suggested an altered anodic biofilm community in response to additional substrates and stress from the complex landfill leachate.
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Affiliation(s)
- Husen Zhang
- Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Florida, United States of America
- * E-mail:
| | - Xi Chen
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Florida, United States of America
| | - Daniel Braithwaite
- Institute for Genomics and Systems Biology, Argonne National Laboratory, Chicago, Illinois, United States of America
| | - Zhen He
- Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
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207
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An J, Kim B, Jang JK, Lee HS, Chang IS. New architecture for modulization of membraneless and single-chambered microbial fuel cell using a bipolar plate-electrode assembly (BEA). Biosens Bioelectron 2014; 59:28-34. [DOI: 10.1016/j.bios.2014.02.063] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 02/21/2014] [Accepted: 02/25/2014] [Indexed: 10/25/2022]
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208
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Ruiz V, Ilhan ZE, Kang DW, Krajmalnik-Brown R, Buitrón G. The source of inoculum plays a defining role in the development of MEC microbial consortia fed with acetic and propionic acid mixtures. J Biotechnol 2014; 182-183:11-8. [DOI: 10.1016/j.jbiotec.2014.04.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 03/18/2014] [Accepted: 04/23/2014] [Indexed: 01/13/2023]
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209
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Influence of setup and carbon source on the bacterial community of biocathodes in microbial electrolysis cells. Enzyme Microb Technol 2014; 61-62:67-75. [DOI: 10.1016/j.enzmictec.2014.04.019] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 04/29/2014] [Accepted: 04/30/2014] [Indexed: 11/18/2022]
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210
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Zhang F, Liu J, Ivanov I, Hatzell MC, Yang W, Ahn Y, Logan BE. Reference and counter electrode positions affect electrochemical characterization of bioanodes in different bioelectrochemical systems. Biotechnol Bioeng 2014; 111:1931-9. [DOI: 10.1002/bit.25253] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 03/11/2014] [Accepted: 03/27/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Fang Zhang
- Department of Civil and Environmental Engineering; Penn State University; 212 Sackett Building University Park Pennsylvania 16802
| | - Jia Liu
- Department of Civil and Environmental Engineering; Penn State University; 212 Sackett Building University Park Pennsylvania 16802
| | - Ivan Ivanov
- Department of Civil and Environmental Engineering; Penn State University; 212 Sackett Building University Park Pennsylvania 16802
| | - Marta C. Hatzell
- Department of Civil and Environmental Engineering; Penn State University; 212 Sackett Building University Park Pennsylvania 16802
| | - Wulin Yang
- Department of Civil and Environmental Engineering; Penn State University; 212 Sackett Building University Park Pennsylvania 16802
| | - Yongtae Ahn
- Department of Civil and Environmental Engineering; Penn State University; 212 Sackett Building University Park Pennsylvania 16802
- Department of Energy Engineering; Gyeongnam National University of Science and Technology; Dongjin-ro 33 Jinju Gyeongnam 660-758 Korea
| | - Bruce E. Logan
- Department of Civil and Environmental Engineering; Penn State University; 212 Sackett Building University Park Pennsylvania 16802
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211
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Koch C, Harnisch F, Schröder U, Müller S. Cytometric fingerprints: evaluation of new tools for analyzing microbial community dynamics. Front Microbiol 2014; 5:273. [PMID: 24926290 PMCID: PMC4044693 DOI: 10.3389/fmicb.2014.00273] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 05/19/2014] [Indexed: 01/20/2023] Open
Abstract
Optical characteristics of individual bacterial cells of natural communities can be measured with flow cytometry (FCM) in high throughput. The resulting data are visualized in cytometric histograms. These histograms represent individual cytometric fingerprints of microbial communities, e.g., at certain time points or microenvironmental conditions. Up to now four tools for analyzing the variation in these cytometric fingerprints are available but have not yet been systematically compared regarding application: Dalmatian Plot, Cytometric Histogram Image Comparison (CHIC), Cytometric Barcoding (CyBar), and FlowFP. In this article these tools were evaluated concerning (i) the required experience of the operator in handling cytometric data sets, (ii) the detection level of changes, (iii) time demand for analysis, and (iv) software requirements. As an illustrative example, FCM was used to characterize the microbial community structure of electroactive microbial biofilms. Their cytometric fingerprints were determined, analyzed with all four tools, and correlated to experimental and functional parameters. The source of inoculum (four different types of wastewater samples) showed the strongest influence on the microbial community structure and biofilm performance while the choice of substrate (acetate or lactate) had no significant effect in the present study. All four evaluation tools were found suitable to monitor structural changes of natural microbial communities. The Dalmatian Plot was shown to be most sensitive to operator impact but nevertheless provided an overview on community shifts. CHIC, CyBar, and FlowFP showed less operator dependence and gave highly resolved information on community structure variation on different detection levels. In conclusion, experimental and productivity parameters correlated with the biofilm structures and practical process integration details were available from cytometric fingerprint analysis.
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Affiliation(s)
- Christin Koch
- Department of Environmental Microbiology, UFZ - Helmholtz-Centre for Environmental Research Leipzig, Germany
| | - Falk Harnisch
- Department of Environmental Microbiology, UFZ - Helmholtz-Centre for Environmental Research Leipzig, Germany ; Institute of Environmental and Sustainable Chemistry, TU Braunschweig Braunschweig, Germany
| | - Uwe Schröder
- Institute of Environmental and Sustainable Chemistry, TU Braunschweig Braunschweig, Germany
| | - Susann Müller
- Department of Environmental Microbiology, UFZ - Helmholtz-Centre for Environmental Research Leipzig, Germany
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212
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An J, Lee HS. Occurrence and implications of voltage reversal in stacked microbial fuel cells. CHEMSUSCHEM 2014; 7:1689-1695. [PMID: 24771553 DOI: 10.1002/cssc.201300949] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/25/2013] [Indexed: 06/03/2023]
Abstract
Voltage reversal in stacked microbial fuel cells (MFCs) is a significant challenge that must be addressed, and the information on its definite cause and occurrence process is still obscure. In this work, we first demonstrated that different anodic reaction rates caused voltage reversal in a stacked MFC. Sluggish reaction rates on the anode in unit 1 of the stacked MFC resulted in a significantly increased anode overpotential of up to 0.132 V, as compared to negligible anode overpotential (0.0247 V) in unit 2. This work clearly verified the process of voltage reversal in the stacked MFC. As the current was gradually increased in the stacked MFC, the voltage in the stacked unit 1 decreased to 0 V prior to that of the stacked unit 2. Then, when the voltage in unit 1 became 0 V, it was converted from a galvanic cell to an electrochemical cell powered by unit 2. We found that the stacked unit 2 provided electrical energy for the stacked unit 1 as a power supply. Finally, the anode potential of the stacked unit 1 significantly increased over cathode potential as current increased further, which caused voltage reversal in unit 1. Voltage reversal occurs in stacked MFCs as a result of non-spontaneous anode overpotential in a unit MFC that has sluggish anode kinetics compared to the other unit MFCs.
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Affiliation(s)
- Junyeong An
- Department of Environmental and Civil Engineering, University of Waterloo, 200 University Avenue West Waterloo, Ontario, N2 L 3G1 (Canada).
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213
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Ishii S, Suzuki S, Norden-Krichmar TM, Phan T, Wanger G, Nealson KH, Sekiguchi Y, Gorby YA, Bretschger O. Microbial population and functional dynamics associated with surface potential and carbon metabolism. THE ISME JOURNAL 2014; 8:963-78. [PMID: 24351938 PMCID: PMC3996694 DOI: 10.1038/ismej.2013.217] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 09/04/2013] [Accepted: 11/02/2013] [Indexed: 11/08/2022]
Abstract
Microbial extracellular electron transfer (EET) to solid surfaces is an important reaction for metal reduction occurring in various anoxic environments. However, it is challenging to accurately characterize EET-active microbial communities and each member's contribution to EET reactions because of changes in composition and concentrations of electron donors and solid-phase acceptors. Here, we used bioelectrochemical systems to systematically evaluate the synergistic effects of carbon source and surface redox potential on EET-active microbial community development, metabolic networks and overall electron transfer rates. The results indicate that faster biocatalytic rates were observed under electropositive electrode surface potential conditions, and under fatty acid-fed conditions. Temporal 16S rRNA-based microbial community analyses showed that Geobacter phylotypes were highly diverse and apparently dependent on surface potentials. The well-known electrogenic microbes affiliated with the Geobacter metallireducens clade were associated with lower surface potentials and less current generation, whereas Geobacter subsurface clades 1 and 2 were associated with higher surface potentials and greater current generation. An association was also observed between specific fermentative phylotypes and Geobacter phylotypes at specific surface potentials. When sugars were present, Tolumonas and Aeromonas phylotypes were preferentially associated with lower surface potentials, whereas Lactococcus phylotypes were found to be closely associated with Geobacter subsurface clades 1 and 2 phylotypes under higher surface potential conditions. Collectively, these results suggest that surface potentials provide a strong selective pressure, at the species and strain level, for both solid surface respirators and fermentative microbes throughout the EET-active community development.
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Affiliation(s)
- Shun'ichi Ishii
- J. Craig Venter Institute, La Jolla, CA, USA
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
- Japan Society for the Promotion of Science (JSPS), Chiyoda-ku, Tokyo, Japan
| | | | | | - Tony Phan
- J. Craig Venter Institute, La Jolla, CA, USA
| | - Greg Wanger
- J. Craig Venter Institute, La Jolla, CA, USA
| | - Kenneth H Nealson
- J. Craig Venter Institute, La Jolla, CA, USA
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, USA
| | - Yuji Sekiguchi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
| | - Yuri A Gorby
- J. Craig Venter Institute, La Jolla, CA, USA
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, USA
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214
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Wu B, Feng C, Huang L, Lv Z, Xie D, Wei C. Anode-biofilm electron transfer behavior and wastewater treatment under different operational modes of bioelectrochemical system. BIORESOURCE TECHNOLOGY 2014; 157:305-309. [PMID: 24584100 DOI: 10.1016/j.biortech.2014.01.088] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 01/18/2014] [Accepted: 01/21/2014] [Indexed: 06/03/2023]
Abstract
Anode-biofilm electron transfer behavior was investigated during the advanced wastewater treatment process by three bioelectrochemical systems (BESs): microbial fuel cell (MFC), MFC operated under short circuit condition (MSC), and microbial electrolysis cell (MEC). Under different operational modes, current produced by the anode biofilm varied from 0.92, 4.15 to 8.21mA in the sequence of MFC, MSC and MEC, respectively. The cyclic voltammetry test on the anode biofilm suggested that the current generation was achieved via various bioelectroactive species with formal potentials at -0.473, -0.402 and -0.345V (vs. SCE). Gibbs free energy and charge transfer resistance data demonstrated that different amounts of available bioelectroactive species functioned in different BESs. The comparative investigation among MFC, MSC and MEC suggested that MEC was the only feasible operational mode for advanced wastewater treatment, because of its superior current generation capability.
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Affiliation(s)
- Baoguo Wu
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Chunhua Feng
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China.
| | - Liqiao Huang
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Zhisheng Lv
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Daohai Xie
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Chaohai Wei
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China.
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215
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Zhu X, Yates MD, Hatzell MC, Ananda Rao H, Saikaly PE, Logan BE. Microbial community composition is unaffected by anode potential. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:1352-1358. [PMID: 24364567 DOI: 10.1021/es404690q] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
There is great controversy on how different set anode potentials affect the performance of a bioelectrochemical system (BES). It is often reported that more positive potentials improve acclimation and performance of exoelectrogenic biofilms, and alter microbial community structure, while in other studies relatively more negative potentials were needed to achieve higher current densities. To address this issue, the biomass, electroactivity, and community structure of anodic biofilms were examined over a wide range of set anode potentials (-0.25, -0.09, 0.21, 0.51, and 0.81 V vs a standard hydrogen electrode, SHE) in single-chamber microbial electrolysis cells. Maximum currents produced using a wastewater inoculum increased with anode potentials in the range of -0.25 to 0.21 V, but decreased at 0.51 and 0.81 V. The maximum currents were positively correlated with increasing biofilm biomass. Pyrosequencing indicated biofilm communities were all similar and dominated by bacteria most similar to Geobacter sulfurreducens. Differences in anode performance with various set potentials suggest that the exoelectrogenic communities self-regulate their exocellular electron transfer pathways to adapt to different anode potentials.
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Affiliation(s)
- Xiuping Zhu
- Department of Civil and Environmental Engineering, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
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216
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Effects of External Resistance on Microbial Fuel Cell’s Performance. THE HANDBOOK OF ENVIRONMENTAL CHEMISTRY 2014. [DOI: 10.1007/698_2014_290] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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217
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Rimboud M, Pocaznoi D, Erable B, Bergel A. Electroanalysis of microbial anodes for bioelectrochemical systems: basics, progress and perspectives. Phys Chem Chem Phys 2014; 16:16349-66. [DOI: 10.1039/c4cp01698j] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Over about the last ten years, microbial anodes have been the subject of a huge number of fundamental studies dealing with an increasing variety of possible application domains.
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Affiliation(s)
- M. Rimboud
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
| | - D. Pocaznoi
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
| | - B. Erable
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
| | - A. Bergel
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
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218
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Gimkiewicz C, Harnisch F. Waste water derived electroactive microbial biofilms: growth, maintenance, and basic characterization. J Vis Exp 2013:50800. [PMID: 24430581 PMCID: PMC4106282 DOI: 10.3791/50800] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The growth of anodic electroactive microbial biofilms from waste water inocula in a fed-batch reactor is demonstrated using a three-electrode setup controlled by a potentiostat. Thereby the use of potentiostats allows an exact adjustment of the electrode potential and ensures reproducible microbial culturing conditions. During growth the current production is monitored using chronoamperometry (CA). Based on these data the maximum current density (jmax) and the coulombic efficiency (CE) are discussed as measures for characterization of the bioelectrocatalytic performance. Cyclic voltammetry (CV), a nondestructive, i.e. noninvasive, method, is used to study the extracellular electron transfer (EET) of electroactive bacteria. CV measurements are performed on anodic biofilm electrodes in the presence of the microbial substrate, i.e. turnover conditions, and in the absence of the substrate, i.e. nonturnover conditions, using different scan rates. Subsequently, data analysis is exemplified and fundamental thermodynamic parameters of the microbial EET are derived and explained: peak potential (Ep), peak current density (jp), formal potential (E(f)) and peak separation (ΔEp). Additionally the limits of the method and the state-of the art data analysis are addressed. Thereby this video-article shall provide a guide for the basic experimental steps and the fundamental data analysis.
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Affiliation(s)
- Carla Gimkiewicz
- Department of Environmental Microbiology, UFZ - Helmholtz-Centre for Environmental Research
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219
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Wang H, Ren ZJ. A comprehensive review of microbial electrochemical systems as a platform technology. Biotechnol Adv 2013; 31:1796-807. [PMID: 24113213 DOI: 10.1016/j.biotechadv.2013.10.001] [Citation(s) in RCA: 334] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 09/17/2013] [Accepted: 10/02/2013] [Indexed: 10/26/2022]
Abstract
Microbial electrochemical systems (MESs) use microorganisms to covert the chemical energy stored in biodegradable materials to direct electric current and chemicals. Compared to traditional treatment-focused, energy-intensive environmental technologies, this emerging technology offers a new and transformative solution for integrated waste treatment and energy and resource recovery, because it offers a flexible platform for both oxidation and reduction reaction oriented processes. All MESs share one common principle in the anode chamber, in which biodegradable substrates, such as waste materials, are oxidized and generate electrical current. In contrast, a great variety of applications have been developed by utilizing this in situ current, such as direct power generation (microbial fuel cells, MFCs), chemical production (microbial electrolysis cells, MECs; microbial electrosynthesis, MES), or water desalination (microbial desalination cells, MDCs). Different from previous reviews that either focus on one function or a specific application aspect, this article provides a comprehensive and quantitative review of all the different functions or system constructions with different acronyms developed so far from the MES platform and summarizes nearly 50 corresponding systems to date. It also provides discussions on the future development of this promising yet early-stage technology.
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Affiliation(s)
- Heming Wang
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO 80309, United States.
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220
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Badalamenti JP, Torres CI, Krajmalnik-Brown R. Coupling dark metabolism to electricity generation using photosynthetic cocultures. Biotechnol Bioeng 2013; 111:223-31. [PMID: 23893620 DOI: 10.1002/bit.25011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 07/05/2013] [Accepted: 07/17/2013] [Indexed: 11/08/2022]
Abstract
We investigated the role of green sulfur bacteria inlight-responsive electricity generation in microbial electrochemical cells (MXCs). We operated MXCs containing either monocultures or defined cocultures of previously enriched phototrophic Chlorobium and anode-respiring Geobacter under anaerobic conditions in the absence of electron donor. Monoculture control MXCs containing Geobacter or Chlorobium neither responded to light nor produced current, respectively. Instead, light-responsive current generation occurred only in coculture MXCs. Current increased above background levels only in the dark and declined slowly over 96 h. This pattern suggested that Chlorobium exhausted intracellular glycogen reserves via dark fermentation to supply an electron donor, presumably acetate, to Geobacter. With medium containing sulfide as the sole photosynthetic electron donor, current generation had a similar and reproducible negative light response. To investigate whether this metabolic interaction also occurred without an electrode, we performed coculture experiments in batch serum bottles. In this setup, sulfide served as the sole electron donor, whose oxidation by Chlorobium was required to provide S(0) as the electron acceptor to Geobacter. Copies of Geobacter 16S rDNA increased approximately 14-fold in batch bottle cocultures containing sulfide compared to those lacking sulfide, and did not decline after termination of sulfide feeding. These results suggest that products of both photosynthesis and dark fermentation by Chlorobium were sufficient both to yield an electrochemical response by Geobacter biofilms, and to promote Geobacter growthin batch cocultures. Our work expands upon the fusion of MXCs with coculture techniques and reinforces the utility of microbial electrochemistry for sensitive, real-time monitoring of microbial interactions in which a metabolic intermediate can be converted to electrical current.
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Affiliation(s)
- Jonathan P Badalamenti
- Swette Center for Environmental Biotechnology, The Biodesign Institute, Arizona State University, Tempe, Arizona
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221
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Croese E, Keesman KJ, Widjaja-Greefkes AHCA, Geelhoed JS, Plugge CM, Sleutels THJA, Stams AJM, Euverink GJW. Relating MEC population dynamics to anode performance from DGGE and electrical data. Syst Appl Microbiol 2013; 36:408-16. [PMID: 23830069 DOI: 10.1016/j.syapm.2013.05.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 05/24/2013] [Accepted: 05/25/2013] [Indexed: 10/26/2022]
Abstract
The microbial electrolysis cell (MEC) is a promising system for H2 production, but little is known about the active microbial population in MEC systems. Therefore, the microbial community of five different MEC graphite felt anodes was analyzed using denaturing gradient gel electrophoresis (DGGE) profiling. The results showed that the bacterial population was very diverse and there were substantial differences between microorganisms in anolyte and anode samples. The archaeal population in the anolyte and at the anodes, and between the different MEC anodes, was very similar. SEM and FISH imaging showed that Archaea were mainly present in the spaces between the electrode fibers and Bacteria were present at the fiber surface, which suggested that Bacteria were the main microorganisms involved in MEC electrochemical activity. Redundancy analysis (RDA) and QR factorization-based estimation (QRE) were used to link the composition of the bacterial community to electrochemical performance of the MEC. The operational mode of the MECs and their consequent effects on current density and anode resistance on the populations were significant. The results showed that the community composition was most strongly correlated with current density. The DGGE band mostly correlated with current represented a Clostridium sticklandii strain, suggesting that this species had a major role in current from acetate generation at the MEC anodes. The combination of RDA and QRE seemed especially promising for obtaining an insight into the part of the microbial population actively involved in electrode interaction in the MEC.
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Affiliation(s)
- Elsemiek Croese
- Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands
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222
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Dhar BR, Lee HS. Membranes for bioelectrochemical systems: challenges and research advances. ENVIRONMENTAL TECHNOLOGY 2013; 34:1751-1764. [PMID: 24350432 DOI: 10.1080/09593330.2013.822007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Increasing energy demand has been a big challenge for current society, as the fossil fuel sources are gradually decreasing. Hence, development of renewable and sustainable energy sources for the future is considered one of the top priorities in national strategic plans. Bioenergy can meet future energy requirements - renewability, sustainability, and even carbon-neutrality. Bioenergy production from wastes and wastewaters is especially attractive because of dual benefits of energy generation and contaminant stabilization. There are several bioenergy technologies using wastes and wastewaters as electron donor, which include anaerobic digestion, dark biohydrogen fermentation, biohydrogen production using photosynthetic microorganisms, and bioelectrochemical systems (BESs). Among them BES seems to be very promising as we can produce a variety of value-added products from wastes and wastewaters, such as electric power, hydrogen gas, hydrogen peroxide, acetate, ethanol etc. Most ofthe traditional BES uses a membrane to separate the anode and cathode chamber, which is essential for improving microbial metabolism on the anode and the recovery of value-added products on the cathode. Performance of BES lacking a membrane can be seriously deteriorated, due to oxygen diffusion or substantial loss of synthesized products. For this reason, usage of a membrane seems essential to facilitate BES performance. However, a membrane can bring several technical challenges to BES application compared to membrane-less BES. These challenges include poor proton permeability, substrate loss, oxygen back diffusion, pH gradient, internal resistance, biofouling, etc. This paper aims to review the major technical barriers associated with membranes and future research directions for their application in BESs.
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Affiliation(s)
- Bipro Ranjan Dhar
- Civil & Environmental Engineering Department, University of Waterloo, 200 University Avenue West, Waterloo, ON Canada N2L 3G1.
| | - Hyung-Sool Lee
- Civil & Environmental Engineering Department, University of Waterloo, 200 University Avenue West, Waterloo, ON Canada N2L 3G1
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223
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Commault AS, Lear G, Packer MA, Weld RJ. Influence of anode potentials on selection of Geobacter strains in microbial electrolysis cells. BIORESOURCE TECHNOLOGY 2013; 139:226-234. [PMID: 23665518 DOI: 10.1016/j.biortech.2013.04.047] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 04/12/2013] [Accepted: 04/12/2013] [Indexed: 06/02/2023]
Abstract
Through their ability to directly transfer electrons to electrodes, Geobacter sp. are key organisms for microbial fuel cell technology. This study presents a simple method to reproducibly select Geobacter-dominated anode biofilms from a mixed inoculum of bacteria using graphite electrodes initially poised at -0.25, -0.36 and -0.42 V vs. Ag/AgCl. The biofilms all produced maximum power density of approximately 270 m Wm(-2) (projected anode surface area). Analysis of 16S rRNA genes and intergenic spacer (ITS) sequences found that the biofilm communities were all dominated by bacteria closely related to Geobacter psychrophilus. Anodes initially poised at -0.25 V reproducibly selected biofilms that were dominated by a strain of G. psychrophilus that was genetically distinct from the strain that dominated the -0.36 and -0.42 V biofilms. This work demonstrates for the first time that closely related strains of Geobacter can have very different competitive advantages at different anode potentials.
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Affiliation(s)
- Audrey S Commault
- Lincoln Agritech Ltd., Lincoln University, P.O. Box 133, Christchurch 7640, New Zealand.
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224
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Song TS, Wu XY, Zhou CC. Effect of different acclimation methods on the performance of microbial fuel cells using phenol as substrate. Bioprocess Biosyst Eng 2013; 37:133-8. [DOI: 10.1007/s00449-013-0975-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 05/15/2013] [Indexed: 10/26/2022]
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225
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Parameswaran P, Bry T, Popat SC, Lusk BG, Rittmann BE, Torres CI. Kinetic, electrochemical, and microscopic characterization of the thermophilic, anode-respiring bacterium Thermincola ferriacetica. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:4934-4940. [PMID: 23544360 DOI: 10.1021/es400321c] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Thermincola ferriacetica is a recently isolated thermophilic, dissimilatory Fe(III)-reducing, Gram-positive bacterium with capability to generate electrical current via anode respiration. Our goals were to determine the maximum rates of anode respiration by T. ferriacetica and to perform a detailed microscopic and electrochemical characterization of the biofilm anode. T. ferriacetica DSM 14005 was grown at 60 °C on graphite-rod anodes poised at -0.06 V (vs) SHE in duplicate microbial electrolysis cells (MECs). The cultures grew rapidly until they achieved a sustained current density of 7-8 A m(-2) with only 10 mM bicarbonate buffer and an average Coulombic Efficiency (CE) of 93%. Cyclic voltammetry performed at maximum current density revealed a Nernst-Monod response with a half saturation potential (EKA) of -0.127 V (vs) SHE. Confocal microscopy images revealed a thick layer of actively respiring cells of T. ferriacetica (~38 μm), which is the first documentation for a gram positive anode respiring bacterium (ARB). Scanning electron microscopy showed a well-developed biofilm with a very dense network of extracellular appendages similar to Geobacter biofilms. The high current densities, a thick biofilm (~38 μm) with multiple layers of active cells, and Nernst-Monod behavior support extracellular electron transfer (EET) through a solid conductive matrix - the first such observation for Gram-positive bacteria. Operating with a controlled anode potential enabled us to grow T. ferriacetica that can use a solid conductive matrix resulting in high current densities that are promising for MXC applications.
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Affiliation(s)
- Prathap Parameswaran
- Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University, P.O. Box 875701, Tempe, Arizona 85287, USA.
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226
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Generation of high current densities by pure cultures of anode-respiring Geoalkalibacter spp. under alkaline and saline conditions in microbial electrochemical cells. mBio 2013; 4:e00144-13. [PMID: 23631915 PMCID: PMC3648901 DOI: 10.1128/mbio.00144-13] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Anode-respiring bacteria (ARB) generate electric current in microbial electrochemical cells (MXCs) by channeling electrons from the oxidation of organic substrates to an electrode. Production of high current densities by monocultures in MXCs has resulted almost exclusively from the activity of Geobacter sulfurreducens, a neutrophilic freshwater Fe(III)-reducing bacterium and the highest-current-producing member documented for the Geobacteraceae family of the Deltaproteobacteria. Here we report high current densities generated by haloalkaliphilic Geoalkalibacter spp., thus broadening the capability for high anode respiration rates by including other genera within the Geobacteraceae. In this study, acetate-fed pure cultures of two related Geoalkalibacter spp. produced current densities of 5.0 to 8.3 and 2.4 to 3.3 A m−2 under alkaline (pH 9.3) and saline (1.7% NaCl) conditions, respectively. Chronoamperometric studies of halophilic Glk. subterraneus DSM 23483 and alkaliphilic Glk. ferrihydriticus DSM 17813 suggested that cells performed long-range electron transfer through electrode-attached biofilms and not through soluble electron shuttles. Glk. ferrihydriticus also oxidized ethanol directly to produce current, with maximum current densities of 5.7 to 7.1 A m−2 and coulombic efficiencies of 84 to 95%. Cyclic voltammetry (CV) elicited a sigmoidal response with characteristic onset, midpoint, and saturation potentials, while CV performed in the absence of an electron donor suggested the involvement of redox molecules in the biofilm that were limited by diffusion. These results matched those previously reported for actively respiring Gb. sulfurreducens biofilms producing similar current densities (~5 to 9 A m−2). This study establishes the highest current densities ever achieved by pure cultures of anode-respiring bacteria (ARB) under alkaline and saline conditions in microbial electrochemical cells (MXCs) and provides the first electrochemical characterization of the genus Geoalkalibacter. Production of high current densities among the Geobacteraceae is no longer exclusive to Geobacter sulfurreducens, suggesting greater versatility for this family in fundamental and applied microbial electrochemical cell (MXC) research than previously considered. Additionally, this work raises the possibility that different members of the Geobacteraceae have conserved molecular mechanisms governing respiratory extracellular electron transfer to electrodes. Thus, the capacity for high current generation may exist in other uncultivated members of this family. Advancement of MXC technology for practical uses must rely on an expanded suite of ARB capable of using different electron donors and producing high current densities under various conditions. Geoalkalibacter spp. can potentially broaden the practical capabilities of MXCs to include energy generation and waste treatment under expanded ranges of salinity and pH.
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227
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228
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Bonanni PS, Bradley DF, Schrott GD, Busalmen JP. Limitations for current production in Geobacter sulfurreducens biofilms. CHEMSUSCHEM 2013; 6:711-720. [PMID: 23417889 DOI: 10.1002/cssc.201200671] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 11/15/2012] [Indexed: 06/01/2023]
Abstract
Devices that exploit electricity produced by electroactive bacteria such as Geobacter sulfurreducens have not yet been demonstrated beyond the laboratory scale. The current densities are far from the maximum that the bacteria can produce because fundamental properties such as the mechanism of extracellular electron transport and factors limiting cell respiration remain unclear. In this work, a strategy for the investigation of electroactive biofilms is presented. Numerical modeling of the response of G. sulfurreducens biofilms cultured on a rotating disk electrode has allowed for the discrimination of different limiting steps in the process of current production within a biofilm. The model outputs reveal that extracellular electron transport limits the respiration rate of the cells furthest from the electrode to the extent that cell division is not possible. The mathematical model also demonstrates that recent findings such as the existence of a redox gradient in actively respiring biofilms can be explained by an electron hopping mechanism but not when considering metallic-like conductivities.
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Affiliation(s)
- P Sebastian Bonanni
- Lab. de bioelectroquímica, Area de electroquímica y corrosíón INTEMA, Juan B. Justo 4302, Mar del Plata, Argentina.
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229
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Cercado B, Byrne N, Bertrand M, Pocaznoi D, Rimboud M, Achouak W, Bergel A. Garden compost inoculum leads to microbial bioanodes with potential-independent characteristics. BIORESOURCE TECHNOLOGY 2013; 134:276-284. [PMID: 23500585 DOI: 10.1016/j.biortech.2013.01.123] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 01/21/2013] [Accepted: 01/22/2013] [Indexed: 06/01/2023]
Abstract
Garden compost leachate was used to form microbial bioanodes under polarization at -0.4, -0.2 and +0.1 V/SCE. Current densities were 6.3 and 8.9 A m(-2) on average at -0.4 and +0.1 V/SCE respectively, with acetate 10 mM. The catalytic cyclic voltammetry (CV) showed similar electrochemical characteristics for all bioanodes and indicated that the lower currents recorded at -0.4V/SCE were due to the slower interfacial electron transfer rate at this potential, consistently with conventional electrochemical kinetics. RNA- and DNA-based DGGE evidenced that the three dominant bacterial groups Geobacter, Anaerophaga and Pelobacter were identical for all bioanodes and did not depend on the polarization potential. Only non-turnover CVs showed differences in the redox equipment of the biofilms, the highest potential promoting multiple electron transfer pathways. This first description of a potential-independent electroactive microbial community opens up promising prospects for the design of stable bioanodes for microbial fuel cells.
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Affiliation(s)
- Bibiana Cercado
- Laboratoire de Génie Chimique (LGC), CNRS, Université de Toulouse (INPT), 4 allée Emile Monso, BP 84234, 31432 Toulouse, France
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230
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Zhang F, Xia X, Luo Y, Sun D, Call DF, Logan BE. Improving startup performance with carbon mesh anodes in separator electrode assembly microbial fuel cells. BIORESOURCE TECHNOLOGY 2013; 133:74-81. [PMID: 23425580 DOI: 10.1016/j.biortech.2013.01.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 12/29/2012] [Accepted: 01/05/2013] [Indexed: 06/01/2023]
Abstract
In a separator electrode assembly microbial fuel cell, oxygen crossover from the cathode inhibits current generation by exoelectrogenic bacteria, resulting in poor reactor startup and performance. To determine the best approach for improving startup performance, the effect of acclimation to a low set potential (-0.2V, versus standard hydrogen electrode) was compared to startup at a higher potential (+0.2 V) or no set potential, and inoculation with wastewater or pre-acclimated cultures. Anodes acclimated to -0.2 V produced the highest power of 1330±60 mW m(-2) for these different anode conditions, but unacclimated wastewater inocula produced inconsistent results despite the use of this set potential. By inoculating reactors with transferred cell suspensions, however, startup time was reduced and high power was consistently produced. These results show that pre-acclimation at -0.2 V consistently improves power production compared to use of a more positive potential or the lack of a set potential.
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Affiliation(s)
- Fang Zhang
- Department of Civil and Environmental Engineering, Penn State University, University Park, PA 16802, USA
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231
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Hirano S, Matsumoto N, Morita M, Sasaki K, Ohmura N. Electrochemical control of redox potential affects methanogenesis of the hydrogenotrophic methanogen Methanothermobacter thermautotrophicus. Lett Appl Microbiol 2013; 56:315-21. [PMID: 23413966 DOI: 10.1111/lam.12059] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 12/27/2012] [Accepted: 12/28/2012] [Indexed: 02/04/2023]
Abstract
To investigate the precise effect of the redox potential on the methanogenesis of the hydrogenotrophic methanogen Methanothermobacter thermautotrophicus by using an electrochemical redox controlling system without adding oxidizing or reducing agents. A bioelectrochemical system was applied to control the redox conditions in culture and to measure the methane-producing activity of M. thermautotrophicus at a constant potential from +0·2 to -0·8 V (vs Ag/AgCl). Methane production and growth of M. thermautotrophicus were 1·6 and 3·5 times increased at -0·8 V, compared with control experiments without electrolysis, respectively, while methanogenesis was suppressed between +0·2 and -0·2 V. A clear relationship between an electrochemically regulated redox potential and methanogenesis was revealed.
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Affiliation(s)
- S Hirano
- Biotechnology Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Abiko, Japan.
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232
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Higgins SR, Lopez RJ, Pagaling E, Yan T, Cooney MJ. Towards a hybrid anaerobic digester-microbial fuel cell integrated energy recovery system: an overview of the development of an electrogenic biofilm. Enzyme Microb Technol 2013; 52:344-51. [PMID: 23608503 DOI: 10.1016/j.enzmictec.2013.02.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 02/26/2013] [Accepted: 02/26/2013] [Indexed: 10/27/2022]
Abstract
An electrogenic biofilm was developed on a macroporous chitosan-carbon nanotube (CHIT-CNT) electrode under constant poised potential (-0.25V versus Ag/AgCl reference electrode) and flow through conditions utilizing the effluent of an anaerobic digester as both the inoculant and substrate for the electrogenic biofilm. After 125 days of inoculation the bioelectrode demonstrated an open circuit potential of -0.62V and a current density of 9.43μAcm(-3) (at -0.25V). Scanning electron microscopy images indicate thorough surface coverage of the biofilm with a high density of bacterial nanowires physically connecting bacteria to bacteria and bacteria to carbon nanotube (electrode surface) suggesting the nanowires are electrically conductive. DGGE was used to identify the major bacterial and archaeal populations.
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Affiliation(s)
- Scott R Higgins
- 1680 East West Rd., POST 109, Hawaii Natural Energy Institute, University of Hawaii, Honolulu HI 96822, United States.
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233
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Dennis PG, Guo K, Imelfort M, Jensen P, Tyson GW, Rabaey K. Spatial uniformity of microbial diversity in a continuous bioelectrochemical system. BIORESOURCE TECHNOLOGY 2013; 129:599-605. [PMID: 23313735 DOI: 10.1016/j.biortech.2012.11.098] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Revised: 11/20/2012] [Accepted: 11/20/2012] [Indexed: 06/01/2023]
Abstract
Bioelectrochemical systems (BESs) are emerging as a technology with diverse future applications. Anode-associated microbial diversity and activity are known to change over time, but the consequences of these dynamics on BES functioning are poorly understood. A novel BES with exchangeable anodic electrodes that facilitates characterisation of microbial communities over time was constructed. The BES, received a mixture of volatile fatty acids and produced 0.13 mA cm(-2) of anodic electrode surface, leading to the removal of 14 g chemical oxygen demand per m2 electrode per day at a coulombic efficiency of 76%. Pyrosequencing of 16S rRNA genes revealed no differences in the diversity of microbial communities associated with different electrodes within a single time point. This finding validates the design for temporal studies as changes in microbial diversity observed over time can be related to community development rather than spatial variation within the reactor.
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Affiliation(s)
- Paul G Dennis
- Advanced Water Management Centre, The University of Queensland, Brisbane, Queensland 4072, Australia
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234
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Ketep SF, Bergel A, Bertrand M, Achouak W, Fourest E. Lowering the applied potential during successive scratching/re-inoculation improves the performance of microbial anodes for microbial fuel cells. BIORESOURCE TECHNOLOGY 2013; 127:448-455. [PMID: 23138069 DOI: 10.1016/j.biortech.2012.09.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 09/03/2012] [Accepted: 09/04/2012] [Indexed: 06/01/2023]
Abstract
Microbial anodes were formed under polarisation at -0.2V/SCE on smooth graphite plate electrodes with paper mill effluents. Primary, secondary and tertiary biofilms were formed by a successive scratching and re-inoculation procedure. The secondary and tertiary biofilms formed while decreasing the polarisation potential allowed the anodes to provide current density of 6A/m(2) at -0.4V/SCE. In contrast, applying -0.4V/SCE initially to form the primary biofilms did not lead to the production of current. Consequently, the scratching/re-inoculation procedure combined with progressive lowering of the applied potential revealed an efficient new procedure that gave efficient microbial anodes able to work at low potential. The observed progressive pH drift to alkaline values above 9 explained the open circuit potentials as low as -0.6 V/SCE. The remarkable performance of the electrode at alkaline pH was attributed to the presence of Desulfuromonas acetexigens as the single dominant species in the tertiary microbial anodes.
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Affiliation(s)
- Stephanie F Ketep
- Centre Technique du Papier, 341 Rue de la Papeterie, 38400 Saint Martin d'Hères, France.
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235
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Patil SA, Hägerhäll C, Gorton L. Electron transfer mechanisms between microorganisms and electrodes in bioelectrochemical systems. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s12566-012-0033-x] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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236
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Badalamenti JP, Torres CI, Krajmalnik-Brown R. Light-responsive current generation by phototrophically enriched anode biofilms dominated by green sulfur bacteria. Biotechnol Bioeng 2012; 110:1020-7. [DOI: 10.1002/bit.24779] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 10/19/2012] [Accepted: 10/24/2012] [Indexed: 11/09/2022]
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237
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238
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Katuri KP, Enright AM, O'Flaherty V, Leech D. Microbial analysis of anodic biofilm in a microbial fuel cell using slaughterhouse wastewater. Bioelectrochemistry 2012; 87:164-71. [DOI: 10.1016/j.bioelechem.2011.12.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 12/01/2011] [Accepted: 12/02/2011] [Indexed: 10/14/2022]
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239
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Miceli JF, Parameswaran P, Kang DW, Krajmalnik-Brown R, Torres CI. Enrichment and analysis of anode-respiring bacteria from diverse anaerobic inocula. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:10349-10355. [PMID: 22909141 DOI: 10.1021/es301902h] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
One of the limitations currently faced by microbial electrochemical cell (MXC) technologies lies in the shortage of different organisms capable of forming a biofilm and channeling electrons from substrates to the anode at high current densities. Using a poised anode (-0.30 V vs Ag/AgCl) and acetate as the electron donor in a MXC, we demonstrated the presence of highly efficient anode-respiring bacteria (ARB) able to produce high current densities (>1.5 A/m(2) anode) in seven out of thirteen environmental samples. These included marshes, lake sediments, saline microbial mats, and anaerobic soils obtained from geographically diverse locations. Our microbial ecology analysis, using pyrosequencing, shows that bacteria related to the genus Geobacter, a known and commonly found ARB, dominate only two of the biofilm communities producing high current; other biofilm communities contained different known and/or novel ARB. The presence of ARB in geographically diverse locations indicates that ARB thrive in a wide range of ecosystems. Studying ARB from different environmental conditions will allow us to better understand the ubiquity of anode respiration, compare the capabilities of different ARB consortia, and find ARB with useful metabolic capacities for future applications.
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Affiliation(s)
- Joseph F Miceli
- Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, Tempe, Arizona, United States
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240
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Xia X, Sun Y, Liang P, Huang X. Long-term effect of set potential on biocathodes in microbial fuel cells: electrochemical and phylogenetic characterization. BIORESOURCE TECHNOLOGY 2012; 120:26-33. [PMID: 22784950 DOI: 10.1016/j.biortech.2012.06.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 06/09/2012] [Accepted: 06/09/2012] [Indexed: 06/01/2023]
Abstract
The long-term effect of set potential on oxygen reducing biocathodes was investigated in terms of electrochemical and biological characteristics. Three biocathodes were poised at 200, 60 and -100 mV vs. saturated calomel electrode (SCE) for 110 days, including the first 17 days for startup. Electrochemical analyses showed that 60 mV was the optimum potential during long-term operation. The performance of all the biocathodes kept increasing after startup, suggesting a period longer than startup time needed to make potential regulation more effective. The inherent characteristics without oxygen transfer limitation were studied. Different from short-term regulation, the amounts of biomass were similar while the specific electrochemical activity was significantly influenced by potential. Moreover, potential showed a strong selection for cathode bacteria. Clones 98% similar with an uncultured Bacteroidetes bacterium clone CG84 accounted for 75% to 80% of the sequences on the biocathodes that showed higher electrochemical activity (60 and -100 mV).
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Affiliation(s)
- Xue Xia
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
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241
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Salvin P, Roos C, Robert F. Tropical mangrove sediments as a natural inoculum for efficient electroactive biofilms. BIORESOURCE TECHNOLOGY 2012; 120:45-51. [PMID: 22784952 DOI: 10.1016/j.biortech.2012.05.131] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2012] [Revised: 05/25/2012] [Accepted: 05/27/2012] [Indexed: 06/01/2023]
Abstract
Chronoamperometry is known to be an efficient way to form electroactive biofilms (EAB) on conductive electrodes. For the first time, tropical mangrove sediments are analyzed as a potential inoculum to form MFC anodes with the use of acetate as substrate. The performance of the EAB-coated carbon cloth electrodes are evaluated according to the maximal current density, the coulombic efficiency and the cyclic voltammogramms. Working electrodes (WE) polarized at -0.2V/SCE gave better results compared to -0.4V/SCE and 0.0 V/SCE. The maximal current density attained was 12A/m(2) with a CE of 24%. Contributions of the EAB in the generation of current were discussed and mechanisms of electronic transfer by the bacteria were discussed. Epifluorescence and SEM images showed the evolution of the biofilms on the electrode surface and the heterogeneity of the structure.
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Affiliation(s)
- Paule Salvin
- Laboratoire des Matériaux et des Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, F-97337 Cayenne, French Guiana
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242
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Set potential regulation reveals additional oxidation peaks of Geobacter sulfurreducens anodic biofilms. Electrochem commun 2012. [DOI: 10.1016/j.elecom.2012.06.013] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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243
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Geothrix fermentans secretes two different redox-active compounds to utilize electron acceptors across a wide range of redox potentials. Appl Environ Microbiol 2012; 78:6987-95. [PMID: 22843516 DOI: 10.1128/aem.01460-12] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The current understanding of dissimilatory metal reduction is based primarily on isolates from the proteobacterial genera Geobacter and Shewanella. However, environments undergoing active Fe(III) reduction often harbor less-well-studied phyla that are equally abundant. In this work, electrochemical techniques were used to analyze respiratory electron transfer by the only known Fe(III)-reducing representative of the Acidobacteria, Geothrix fermentans. In contrast to previously characterized metal-reducing bacteria, which typically reach maximal rates of respiration at electron acceptor potentials of 0 V versus standard hydrogen electrode (SHE), G. fermentans required potentials as high as 0.55 V to respire at its maximum rate. In addition, G. fermentans secreted two different soluble redox-active electron shuttles with separate redox potentials (-0.2 V and 0.3 V). The compound with the lower midpoint potential, responsible for 20 to 30% of electron transfer activity, was riboflavin. The behavior of the higher-potential compound was consistent with hydrophilic UV-fluorescent molecules previously found in G. fermentans supernatants. Both electron shuttles were also produced when cultures were grown with Fe(III), but not when fumarate was the electron acceptor. This study reveals that Geothrix is able to take advantage of higher-redox-potential environments, demonstrates that secretion of flavin-based shuttles is not confined to Shewanella, and points to the existence of high-potential-redox-active compounds involved in extracellular electron transfer. Based on differences between the respiratory strategies of Geothrix and Geobacter, these two groups of bacteria could exist in distinctive environmental niches defined by redox potential.
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244
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Abstract
Geobacter sulfurreducens can form electrically conductive biofilms, but the potential for conductivity through mixed-species biofilms has not been examined. A current-producing biofilm grown from a wastewater sludge inoculum was highly conductive with low charge transfer resistance even though microorganisms other than Geobacteraceae accounted for nearly half the microbial community.
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245
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Franks AE, Glaven RH, Lovley DR. Real-time spatial gene expression analysis within current-producing biofilms. CHEMSUSCHEM 2012; 5:1092-1098. [PMID: 22577044 DOI: 10.1002/cssc.201100714] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 03/06/2011] [Indexed: 05/31/2023]
Abstract
The expression of genes involved in central metabolism and extracellular electron transfer was examined in real-time in current-producing anode biofilms of Geobacter sulfurreducens. Strains of G. sulfurreducens were generated, in which the expression of the gene for a short half-life fluorescent protein was placed under control of the promoter of the genes of interest. Anode biofilms were grown in a chamber that permitted direct examination of the cell fluorescence with confocal scanning laser microscopy. Studies on nifD and citrate synthase expression in response to environmental changes demonstrated that the reporter system revealed initiation and termination of gene transcription. Uniform expression throughout the biofilms was noted for the genes for citrate synthase; PilA, the structural protein of the conductive pili; and OmcZ, a c-type cytochrome essential for optimal current production, which was localized at the anode-biofilm interface. These results demonstrate that even cells at great distance from the anode, or within expected low-pH zones, are metabolically active and likely to contribute to current production and that there are factors other than gene expression differences influencing the distribution of OmcZ. This real-time reporter approach is likely to be a useful tool in optimizing the design of technologies relying on microbe-electrode interactions.
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Affiliation(s)
- Ashley E Franks
- Department of Microbiology, University of Massachusetts, Morrill IVN, 639 North Pleasant Street, Amherst, MA, USA.
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246
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Katuri KP, Rengaraj S, Kavanagh P, O'Flaherty V, Leech D. Charge transport through Geobacter sulfurreducens biofilms grown on graphite rods. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:7904-7913. [PMID: 22524560 DOI: 10.1021/la2047036] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Biofilms of the electroactive bacterium Geobacter sulfurreducens were induced to grow on graphite-rod electrodes under a potential of 0 V (vs Ag/AgCl) in the presence of acetate as an electron donor. Increased anodic currents for bioelectrocatalytic oxidation of acetate were obtained when the electrodes were incubated for longer periods with periodic electron-donor feeding. The maximum current density for acetate oxidation increased 2.8-fold, and the biofilm thickness increased by 4.25-fold, over a time period of 83-147 h. Cyclic voltammetry in the presence of acetate supports a model of heterogeneous electron transfer, one electron at time, from biofilm to electrode through a dominant redox species centered at -0.41 V vs Ag/AgCl. Voltammetry performed under nonturnover conditions provided an estimate of the surface coverage of the redox species of 25 nmol/cm(2). This value was used to estimate a redox species concentration of 7.3 mM within the 34-μm-thick biofilm and a charge-transport diffusion coefficient of 3.6 × 10(-7) cm(2)/s. This value of diffusion coefficient is greater than that observed in traditional thin-film voltammetric studies with redox polymer films containing much higher surface concentrations of redox species and might be associated with proton transport to ensure electroneutrality within the biofilm upon electrolysis.
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Affiliation(s)
- Krishna P Katuri
- School of Chemistry, National University of Ireland Galway, University Road, Galway, Ireland
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247
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Gardel EJ, Nielsen ME, Grisdela PT, Girguis PR. Duty cycling influences current generation in multi-anode environmental microbial fuel cells. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:5222-5229. [PMID: 22497491 DOI: 10.1021/es204622m] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Improving microbial fuel cell (MFC) performance continues to be the subject of research, yet the role of operating conditions, specifically duty cycling, on MFC performance has been modestly addressed. We present a series of studies in which we use a 15-anode environmental MFC to explore how duty cycling (variations in the time an anode is connected) influences cumulative charge, current, and microbial composition. The data reveal particular switching intervals that result in the greatest time-normalized current. When disconnection times are sufficiently short, there is a striking decrease in current due to an increase in the overall electrode reaction resistance. This was observed over a number of whole cell potentials. Based on these results, we posit that replenishment of depleted electron donors within the biofilm and surrounding diffusion layer is necessary for maximum charge transfer, and that proton flux may be not limiting in the highly buffered aqueous phases that are common among environmental MFCs. Surprisingly, microbial diversity analyses found no discernible difference in gross community composition among duty cycling treatments, suggesting that duty cycling itself has little or no effect. Such duty cycling experiments are valuable in determining which factors govern performance of bioelectrochemical systems and might also be used to optimize field-deployed systems.
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Affiliation(s)
- Emily J Gardel
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street Cambridge, Massachusetts 02138, USA
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248
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Nercessian O, Parot S, Délia ML, Bergel A, Achouak W. Harvesting electricity with Geobacter bremensis isolated from compost. PLoS One 2012; 7:e34216. [PMID: 22470538 PMCID: PMC3314594 DOI: 10.1371/journal.pone.0034216] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Accepted: 02/25/2012] [Indexed: 11/18/2022] Open
Abstract
Electrochemically active (EA) biofilms were formed on metallic dimensionally stable anode-type electrode (DSA), embedded in garden compost and polarized at +0.50 V/SCE. Analysis of 16S rRNA gene libraries revealed that biofilms were heavily enriched in Deltaproteobacteria in comparison to control biofilms formed on non-polarized electrodes, which were preferentially composed of Gammaproteobacteria and Firmicutes. Among Deltaproteobacteria, sequences affiliated with Pelobacter and Geobacter genera were identified. A bacterial consortium was cultivated, in which 25 isolates were identified as Geobacter bremensis. Pure cultures of 4 different G. bremensis isolates gave higher current densities (1400 mA/m2 on DSA, 2490 mA/m2 on graphite) than the original multi-species biofilms (in average 300 mA/m2 on DSA) and the G. bremensis DSM type strain (100–300 A/m2 on DSA; 2485 mA/m2 on graphite). FISH analysis confirmed that G. bremensis represented a minor fraction in the original EA biofilm, in which species related to Pelobacter genus were predominant. The Pelobacter type strain did not show EA capacity, which can explain the lower performance of the multi-species biofilms. These results stressed the great interest of extracting and culturing pure EA strains from wild EA biofilms to improve the current density provided by microbial anodes.
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Affiliation(s)
- Olivier Nercessian
- CEA, DSV, IBEB, SBVME, Lab Ecol Microb Rhizosphere and Environ Extrem (LEMiRE), Saint-Paul-lez-Durance, France
- CNRS UMR 7265 and FR CNRS 3098 ECCOREV, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, Saint-Paul-lez-Durance, France
| | - Sandrine Parot
- Laboratoire de Génie Chimique, Centre National de la Recherche Scientifique, Université de Toulouse (INPT), Toulouse, France
| | - Marie-Line Délia
- Laboratoire de Génie Chimique, Centre National de la Recherche Scientifique, Université de Toulouse (INPT), Toulouse, France
| | - Alain Bergel
- Laboratoire de Génie Chimique, Centre National de la Recherche Scientifique, Université de Toulouse (INPT), Toulouse, France
| | - Wafa Achouak
- CEA, DSV, IBEB, SBVME, Lab Ecol Microb Rhizosphere and Environ Extrem (LEMiRE), Saint-Paul-lez-Durance, France
- CNRS UMR 7265 and FR CNRS 3098 ECCOREV, Saint-Paul-lez-Durance, France
- Aix-Marseille Université, Saint-Paul-lez-Durance, France
- * E-mail:
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249
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Song TS, Cai HY, Yan ZS, Zhao ZW, Jiang HL. Various voltage productions by microbial fuel cells with sedimentary inocula taken from different sites in one freshwater lake. BIORESOURCE TECHNOLOGY 2012; 108:68-75. [PMID: 22264430 DOI: 10.1016/j.biortech.2011.11.136] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 11/07/2011] [Accepted: 11/12/2011] [Indexed: 05/31/2023]
Abstract
In this study, single-chamber microbial fuel cells (MFCs) were inoculated with sedimentary samples taken from one freshwater shallow lake. After 98 days of operation, it was found that sedimentary inocula had strong effect on MFC performances, and Fe(III) contents in sediments were significantly related to voltage values produced from MFCs. Inoculation of the sedimentary sample from the site with the highest Fe(III) content led to the production of the highest voltage with a value of 580 mV, while voltage from the MFC inoculated with sediments from the site with the lowest Fe(III) concentration was less than 30 mV at the end of the experiments. In addition, microbial communities of anode biofilms from the MFCs with the highest and lowest voltages showed significant difference. This study will help enable scientific decisions to be made regarding the selection of freshwater sediments as MFC inoculum, and survey exoelectrogenic microorganisms within sediments.
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Affiliation(s)
- Tian-Shun Song
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
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250
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Durruty I, Bonanni PS, González JF, Busalmen JP. Evaluation of potato-processing wastewater treatment in a microbial fuel cell. BIORESOURCE TECHNOLOGY 2012; 105:81-87. [PMID: 22178494 DOI: 10.1016/j.biortech.2011.11.095] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 11/16/2011] [Accepted: 11/24/2011] [Indexed: 05/31/2023]
Abstract
Wastewaters from potato-processing industries have been traditionally treated by a sequence of steps that include the production of methane as the anaerobic one. This work explores the feasibility of replacing or supplementing methanogenesis with the emerging technology of microbial fuel cells (MFCs). Electricity producing biofilms have been enriched from a real anaerobic sludge, and the conversion of potato-processing wastewater into electricity has been studied. When tested as a single treatment step, MFCs were able to process the wastewater with high COD removal but with low energetic conversion efficiency. On the other hand, as a complimentary step for methanogenesis, they improved conversion efficiency and significantly reduced the organic matter load of the final effluent. These results point at the combination of the energetic yield of methanogenesis and the improved COD removal of the electricity producing treatment as the implementation choice.
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Affiliation(s)
- Ignacio Durruty
- Grupo de Ingeniería Bioquímica, Facultad de Ingeniería, UNMdP, Juan B. Justo 4302, Mar del Plata, Argentina.
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