151
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Giddings CGS, Nevin KP, Woodward T, Lovley DR, Butler CS. Simplifying microbial electrosynthesis reactor design. Front Microbiol 2015; 6:468. [PMID: 26029199 PMCID: PMC4432714 DOI: 10.3389/fmicb.2015.00468] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 04/29/2015] [Indexed: 01/05/2023] Open
Abstract
Microbial electrosynthesis, an artificial form of photosynthesis, can efficiently convert carbon dioxide into organic commodities; however, this process has only previously been demonstrated in reactors that have features likely to be a barrier to scale-up. Therefore, the possibility of simplifying reactor design by both eliminating potentiostatic control of the cathode and removing the membrane separating the anode and cathode was investigated with biofilms of Sporomusa ovata. S. ovata reduces carbon dioxide to acetate and acts as the microbial catalyst for plain graphite stick cathodes as the electron donor. In traditional ‘H-cell’ reactors, where the anode and cathode chambers were separated with a proton-selective membrane, the rates and columbic efficiencies of microbial electrosynthesis remained high when electron delivery at the cathode was powered with a direct current power source rather than with a potentiostat-poised cathode utilized in previous studies. A membrane-less reactor with a direct-current power source with the cathode and anode positioned to avoid oxygen exposure at the cathode, retained high rates of acetate production as well as high columbic and energetic efficiencies. The finding that microbial electrosynthesis is feasible without a membrane separating the anode from the cathode, coupled with a direct current power source supplying the energy for electron delivery, is expected to greatly simplify future reactor design and lower construction costs.
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Affiliation(s)
- Cloelle G S Giddings
- Department of Civil and Environmental Engineering, University of Massachusetts at Amherst Amherst, MA, USA
| | - Kelly P Nevin
- Department of Microbiology, University of Massachusetts at Amherst Amherst, MA, USA
| | - Trevor Woodward
- Department of Microbiology, University of Massachusetts at Amherst Amherst, MA, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts at Amherst Amherst, MA, USA
| | - Caitlyn S Butler
- Department of Civil and Environmental Engineering, University of Massachusetts at Amherst Amherst, MA, USA
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152
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Nybo SE, Khan NE, Woolston BM, Curtis WR. Metabolic engineering in chemolithoautotrophic hosts for the production of fuels and chemicals. Metab Eng 2015; 30:105-120. [PMID: 25959019 DOI: 10.1016/j.ymben.2015.04.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 04/06/2015] [Accepted: 04/29/2015] [Indexed: 12/19/2022]
Abstract
The ability of autotrophic organisms to fix CO2 presents an opportunity to utilize this 'greenhouse gas' as an inexpensive substrate for biochemical production. Unlike conventional heterotrophic microorganisms that consume carbohydrates and amino acids, prokaryotic chemolithoautotrophs have evolved the capacity to utilize reduced chemical compounds to fix CO2 and drive metabolic processes. The use of chemolithoautotrophic hosts as production platforms has been renewed by the prospect of metabolically engineered commodity chemicals and fuels. Efforts such as the ARPA-E electrofuels program highlight both the potential and obstacles that chemolithoautotrophic biosynthetic platforms provide. This review surveys the numerous advances that have been made in chemolithoautotrophic metabolic engineering with a focus on hydrogen oxidizing bacteria such as the model chemolithoautotrophic organism (Ralstonia), the purple photosynthetic bacteria (Rhodobacter), and anaerobic acetogens. Two alternative strategies of microbial chassis development are considered: (1) introducing or enhancing autotrophic capabilities (carbon fixation, hydrogen utilization) in model heterotrophic organisms, or (2) improving tools for pathway engineering (transformation methods, promoters, vectors etc.) in native autotrophic organisms. Unique characteristics of autotrophic growth as they relate to bioreactor design and process development are also discussed in the context of challenges and opportunities for genetic manipulation of organisms as production platforms.
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Affiliation(s)
- S Eric Nybo
- Department of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, MI, United States
| | - Nymul E Khan
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA, United States
| | - Benjamin M Woolston
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Wayne R Curtis
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA, United States.
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153
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Wang H, Luo H, Fallgren PH, Jin S, Ren ZJ. Bioelectrochemical system platform for sustainable environmental remediation and energy generation. Biotechnol Adv 2015; 33:317-34. [DOI: 10.1016/j.biotechadv.2015.04.003] [Citation(s) in RCA: 177] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Revised: 03/29/2015] [Accepted: 04/06/2015] [Indexed: 10/23/2022]
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154
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Alamethicin suppresses methanogenesis and promotes acetogenesis in bioelectrochemical systems. Appl Environ Microbiol 2015; 81:3863-8. [PMID: 25819972 DOI: 10.1128/aem.00594-15] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 03/23/2015] [Indexed: 11/20/2022] Open
Abstract
Microbial electrosynthesis (MES) systems with mixed cultures often generate a variety of gaseous and soluble chemicals. Methane is the primary end product in mixed-culture MES because it is the thermodynamically most favorable reduction product of CO2. Here, we show that the peptaibol alamethicin selectively suppressed the growth of methanogens in mixed-culture MES systems, resulting in a shift of the solution and cathode communities to an acetate-producing system dominated by Sporomusa, a known acetogenic genus in MES systems. Archaea in the methane-producing control were dominated by Methanobrevibacter species, but no Archaea were detected in the alamethicin-treated reactors. No methane was detected in the mixed-culture reactors treated with alamethicin over 10 cycles (∼ 3 days each). Instead, acetate was produced at an average rate of 115 nmol ml(-1) day(-1), similar to the rate reported previously for pure cultures of Sporomusa ovata on biocathodes. Mixed-culture control reactors without alamethicin generated methane at nearly 100% coulombic recovery, and no acetate was detected. These results show that alamethicin is effective for the suppression of methanogen growth in MES systems and that its use enables the production of industrially relevant organic compounds by the inhibition of methanogenesis.
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155
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Complete Genome Sequences of Sulfurospirillum Strains UCH001 and UCH003 Isolated from Groundwater in Japan. GENOME ANNOUNCEMENTS 2015; 3:3/2/e00236-15. [PMID: 25814615 PMCID: PMC4384155 DOI: 10.1128/genomea.00236-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sulfurospirillum strains UCH001 and UCH003 were isolated from anaerobic cis-1,2-dichloroethene-dechlorinating microbial consortia derived from groundwater in Japan. Here, we report the complete genome sequences of strains UCH001 and UCH003.
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156
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Zhou M, Freguia S, Dennis PG, Keller J, Rabaey K. Development of bioelectrocatalytic activity stimulates mixed-culture reduction of glycerol in a bioelectrochemical system. Microb Biotechnol 2015; 8:483-9. [PMID: 25817314 PMCID: PMC4408180 DOI: 10.1111/1751-7915.12240] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 10/12/2014] [Indexed: 11/30/2022] Open
Abstract
In a microbial bioelectrochemical system (BES), organic substrate such as glycerol can be reductively converted to 1,3-propanediol (1,3-PDO) by a mixed population biofilm growing on the cathode. Here, we show that 1,3-PDO yields positively correlated to the electrons supplied, increasing from 0.27 ± 0.13 to 0.57 ± 0.09 mol PDO mol−1 glycerol when the cathodic current switched from 1 A m−2 to 10 A m−2. Electrochemical measurements with linear sweep voltammetry (LSV) demonstrated that the biofilm was bioelectrocatalytically active and that the cathodic current was greatly enhanced only in the presence of both biofilm and glycerol, with an onset potential of −0.46 V. This indicates that glycerol or its degradation products effectively served as cathodic electron acceptor. During long-term operation (> 150 days), however, the yield decreased gradually to 0.13 ± 0.02 mol PDO mol−1 glycerol, and the current–product correlation disappeared. The onset potentials for cathodic current decreased to −0.58 V in the LSV tests at this stage, irrespective of the presence or absence of glycerol, with electrons from the cathode almost exclusively used for hydrogen evolution (accounted for 99.9% and 89.5% of the electrons transferred at glycerol and glycerol-free conditions respectively). Community analysis evidenced a decreasing relative abundance of Citrobacter in the biofilm, indicating a community succession leading to cathode independent processes relative to the glycerol. It is thus shown here that in processes where substrate conversion can occur independently of the electrode, electroactive microorganisms can be outcompeted and effectively disconnected from the substrate.
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Affiliation(s)
- Mi Zhou
- Advanced Water Management Centre, The University of Queensland, Brisbane; Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
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157
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Tremblay PL, Zhang T. Electrifying microbes for the production of chemicals. Front Microbiol 2015; 6:201. [PMID: 25814988 PMCID: PMC4356085 DOI: 10.3389/fmicb.2015.00201] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 02/24/2015] [Indexed: 01/06/2023] Open
Abstract
Powering microbes with electrical energy to produce valuable chemicals such as biofuels has recently gained traction as a biosustainable strategy to reduce our dependence on oil. Microbial electrosynthesis (MES) is one of the bioelectrochemical approaches developed in the last decade that could have critical impact on the current methods of chemical synthesis. MES is a process in which electroautotrophic microbes use electrical current as electron source to reduce CO2 to multicarbon organics. Electricity necessary for MES can be harvested from renewable resources such as solar energy, wind turbine, or wastewater treatment processes. The net outcome is that renewable energy is stored in the covalent bonds of organic compounds synthesized from greenhouse gas. This review will discuss the future of MES and the challenges that lie ahead for its development into a mature technology.
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Affiliation(s)
- Pier-Luc Tremblay
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm Denmark
| | - Tian Zhang
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm Denmark
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158
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Fu Q, Kuramochi Y, Fukushima N, Maeda H, Sato K, Kobayashi H. Bioelectrochemical analyses of the development of a thermophilic biocathode catalyzing electromethanogenesis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:1225-1232. [PMID: 25544349 DOI: 10.1021/es5052233] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The use of thermophilic microorganisms as biocatalysts for electromethanogenesis was investigated. Single-chamber reactors inoculated with thermophiles and operated at 55 °C showed high CH4 production rates (max. 1103 mmol m(–2) day(–1) at an applied voltage of 0.8 V) with current-capture efficiencies >90%, indicating that thermophiles have high potential as biocatalysts. To improve the electromethanogenic activity, the developed biocathode was transferred to a two-chamber reactor and operated at a poised potential of −0.5 V vs SHE. The CH4 production rates of the biocathode were enhanced approximately 6-fold in 160 h of poised-potential incubation, indicating that the acclimation of the biocathode resulted in performance improvement. Compositional alteration of the cathodic microbiota suggested that a Methanothermobacter-related methanogen and synergistetes- and thermotogae-related bacteria were selected during the acclimation. Cyclic voltammetry of the “acclimated” biocathode showed an augmented cathodic catalytic wave with a midpoint potential at ca. −0.35 V vs SHE. Moreover, the biocathode was able to catalyze electromethanogenesis at −0.35 V vs SHE. These results suggested that the ability of the biocathode to catalyze electromethanogenesis via direct electron transfer was enhanced by the acclimation. This study provides new technological and fundamental information on electromethanogenic bioelectrochemical systems (BESs) that may be extended to other BESs.
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159
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Draft Genome Sequence of Sulfurospirillum sp. Strain MES, Reconstructed from the Metagenome of a Microbial Electrosynthesis System. GENOME ANNOUNCEMENTS 2015; 3:3/1/e01336-14. [PMID: 25593246 PMCID: PMC4299888 DOI: 10.1128/genomea.01336-14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A draft genome of Sulfurospirillum sp. strain MES was isolated through taxonomic binning of a metagenome sequenced from a microbial electrosynthesis system (MES) actively producing acetate and hydrogen. The genome contains the nosZDFLY genes, which are involved in nitrous oxide reduction, suggesting the potential role of this strain in denitrification.
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160
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Ganigué R, Puig S, Batlle-Vilanova P, Balaguer MD, Colprim J. Microbial electrosynthesis of butyrate from carbon dioxide. Chem Commun (Camb) 2015; 51:3235-8. [DOI: 10.1039/c4cc10121a] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This work proves for the first time the bioelectrochemical production of butyrate from CO2as a sole carbon source.
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Affiliation(s)
- R. Ganigué
- LEQUIA
- Institute of the Environment
- University of Girona
- Campus de Montilivi
- Girona
| | - S. Puig
- LEQUIA
- Institute of the Environment
- University of Girona
- Campus de Montilivi
- Girona
| | - P. Batlle-Vilanova
- LEQUIA
- Institute of the Environment
- University of Girona
- Campus de Montilivi
- Girona
| | - M. D. Balaguer
- LEQUIA
- Institute of the Environment
- University of Girona
- Campus de Montilivi
- Girona
| | - J. Colprim
- LEQUIA
- Institute of the Environment
- University of Girona
- Campus de Montilivi
- Girona
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161
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A previously uncharacterized, nonphotosynthetic member of the Chromatiaceae is the primary CO2-fixing constituent in a self-regenerating biocathode. Appl Environ Microbiol 2014; 81:699-712. [PMID: 25398855 DOI: 10.1128/aem.02947-14] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Biocathode extracellular electron transfer (EET) may be exploited for biotechnology applications, including microbially mediated O2 reduction in microbial fuel cells and microbial electrosynthesis. However, biocathode mechanistic studies needed to improve or engineer functionality have been limited to a few select species that form sparse, homogeneous biofilms characterized by little or no growth. Attempts to cultivate isolates from biocathode environmental enrichments often fail due to a lack of some advantage provided by life in a consortium, highlighting the need to study and understand biocathode consortia in situ. Here, we present metagenomic and metaproteomic characterization of a previously described biocathode biofilm (+310 mV versus a standard hydrogen electrode [SHE]) enriched from seawater, reducing O2, and presumably fixing CO2 for biomass generation. Metagenomics identified 16 distinct cluster genomes, 15 of which could be assigned at the family or genus level and whose abundance was roughly divided between Alpha- and Gammaproteobacteria. A total of 644 proteins were identified from shotgun metaproteomics and have been deposited in the the ProteomeXchange with identifier PXD001045. Cluster genomes were used to assign the taxonomic identities of 599 proteins, with Marinobacter, Chromatiaceae, and Labrenzia the most represented. RubisCO and phosphoribulokinase, along with 9 other Calvin-Benson-Bassham cycle proteins, were identified from Chromatiaceae. In addition, proteins similar to those predicted for iron oxidation pathways of known iron-oxidizing bacteria were observed for Chromatiaceae. These findings represent the first description of putative EET and CO2 fixation mechanisms for a self-regenerating, self-sustaining multispecies biocathode, providing potential targets for functional engineering, as well as new insights into biocathode EET pathways using proteomics.
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162
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LaBelle EV, Marshall CW, Gilbert JA, May HD. Influence of acidic pH on hydrogen and acetate production by an electrosynthetic microbiome. PLoS One 2014; 9:e109935. [PMID: 25333313 PMCID: PMC4198145 DOI: 10.1371/journal.pone.0109935] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 09/09/2014] [Indexed: 12/02/2022] Open
Abstract
Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (∼5). Hydrogen production by biocathodes poised at −600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ∼5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ∼6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at −765 mV (0.065 mA/cm2 sterile control at −800 mV) by the Acetobacterium-dominated community. Supplying −800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured).
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Affiliation(s)
- Edward V. LaBelle
- Department of Microbiology & Immunology, Marine Biomedicine & Environmental Science Center, Hollings Marine Laboratory, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Christopher W. Marshall
- Institute for Genomic and Systems Biology, Argonne National Laboratory, Argonne, Illinois, United States of America
| | - Jack A. Gilbert
- Institute for Genomic and Systems Biology, Argonne National Laboratory, Argonne, Illinois, United States of America
- Department of Ecology and Evolution, University of Chicago, Chicago, Illinois, United States of America
- Marine Biological Laboratory, Woods Hole, Massachusetts, United States of America
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Harold D. May
- Department of Microbiology & Immunology, Marine Biomedicine & Environmental Science Center, Hollings Marine Laboratory, Medical University of South Carolina, Charleston, South Carolina, United States of America
- * E-mail:
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163
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Sharma M, Bajracharya S, Gildemyn S, Patil SA, Alvarez-Gallego Y, Pant D, Rabaey K, Dominguez-Benetton X. A critical revisit of the key parameters used to describe microbial electrochemical systems. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2014.02.111] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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164
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Electroactive bacteria—molecular mechanisms and genetic tools. Appl Microbiol Biotechnol 2014; 98:8481-95. [DOI: 10.1007/s00253-014-6005-z] [Citation(s) in RCA: 153] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/28/2014] [Accepted: 07/30/2014] [Indexed: 12/15/2022]
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165
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Venkata Mohan S, Velvizhi G, Vamshi Krishna K, Lenin Babu M. Microbial catalyzed electrochemical systems: a bio-factory with multi-facet applications. BIORESOURCE TECHNOLOGY 2014; 165:355-364. [PMID: 24791713 DOI: 10.1016/j.biortech.2014.03.048] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 03/08/2014] [Accepted: 03/12/2014] [Indexed: 06/03/2023]
Abstract
Microbial catalyzed electrochemical systems (MCES) have been intensively pursued in both basic and applied research as a futuristic and sustainable platform specifically in harnessing energy and generating value added bio-products. MCES have documented multiple/diverse applications which include microbial fuel cell (for harnessing bioelectricity), bioelectrochemical treatment system (waste remediation), bioelectrochemical system (bio-electrosynthesis of various value added products) and microbial electrolytic cell (H2 production at lower applied potential). Microorganisms function as biocatalyst in these fuel cell systems and the resulting electron flux from metabolism plays pivotal role in bio-electrogenesis. Exo-electron transfer machineries and strategies that regulate metabolic flux towards exo-electron transport were delineated. This review addresses the contemporary progress and advances made in MCES, focusing on its application towards value addition and waste remediation.
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Affiliation(s)
- S Venkata Mohan
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India.
| | - G Velvizhi
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
| | - K Vamshi Krishna
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
| | - M Lenin Babu
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
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166
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Hallenbeck PC, Grogger M, Veverka D. Recent Advances in Microbial Electrocatalysis. Electrocatalysis (N Y) 2014. [DOI: 10.1007/s12678-014-0198-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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167
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Chain elongation in anaerobic reactor microbiomes to recover resources from waste. Curr Opin Biotechnol 2014; 27:115-22. [PMID: 24487179 DOI: 10.1016/j.copbio.2014.01.003] [Citation(s) in RCA: 208] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 12/30/2013] [Accepted: 01/06/2014] [Indexed: 01/17/2023]
Abstract
Different microbial pathways can elongate the carbon chains of molecules in open cultures of microbial populations (i.e. reactor microbiomes) under anaerobic conditions. Here, we discuss three such pathways: 1. homoacetogenesis to combine two carbon dioxide molecules into acetate; 2. succinate formation to elongate glycerol with one carbon from carbon dioxide; and 3. reverse β oxidation to elongate short-chain carboxylates with two carbons into medium-chain carboxylates, leading to more energy-dense and insoluble products (e.g. easier to separate from solution). The ability to use reactor microbiomes to treat complex substrates can simultaneously address two pressing issues: 1. providing proper waste management; and 2. producing renewable chemicals and fuels.
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168
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Liu XW, Li WW, Yu HQ. Cathodic catalysts in bioelectrochemical systems for energy recovery from wastewater. Chem Soc Rev 2014; 43:7718-45. [DOI: 10.1039/c3cs60130g] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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