1
|
Zhang L, Chen S, Yang Y, Xie S, Luo L, Lu Y, Luan T. Chlorophyll a acts as a natural photosensitizer to drive nitrate reduction in nonphotosynthetic microorganisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:174119. [PMID: 38906304 DOI: 10.1016/j.scitotenv.2024.174119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 06/16/2024] [Accepted: 06/16/2024] [Indexed: 06/23/2024]
Abstract
With the death and decomposition of widely distributed photosynthetic organisms, free natural pigments are often detected in surface water, sediment and soil. Whether free pigments can act as photosensitizers to drive biophotoelectrochemical metabolism in nonphotosynthetic microorganisms has not been reported. In this work, we provide direct evidence for the photoelectrophic relationship between extracellular chlorophyll a (Chl a) and nonphotosynthetic microorganisms. The results show that 10 μg of Chl a can produce significant photoelectrons (∼0.34 A/cm2) upon irradiation to drive nitrate reduction in Shewanella oneidensis. Chl a undergoes structural changes during the photoelectric process, thus the ability of Chl a to generate a photocurrent decreases gradually with increasing illumination time. These changes are greater in the presence of microorganisms than in the absence of microorganisms. Photoelectron transport from Chl a to S. oneidensis occurs through a direct pathway involving the cytochromes MtrA, MtrB, MtrC and CymA but not through an indirect pathway involving riboflavin. These findings reveal a novel photoelectrotrophic linkage between natural photosynthetic pigments and nonphototrophic microorganisms, which has important implications for the biogeochemical cycle of nitrogen in various natural environments where Chl a is distributed.
Collapse
Affiliation(s)
- Lanlan Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China
| | - Shanshan Chen
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China.
| | - Yuting Yang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Shuyi Xie
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Lijuan Luo
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China
| | - Yaobin Lu
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China
| | - Tiangang Luan
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China
| |
Collapse
|
2
|
Harnisch F, Deutzmann JS, Boto ST, Rosenbaum MA. Microbial electrosynthesis: opportunities for microbial pure cultures. Trends Biotechnol 2024; 42:1035-1047. [PMID: 38431514 PMCID: PMC11310912 DOI: 10.1016/j.tibtech.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/05/2024] [Accepted: 02/05/2024] [Indexed: 03/05/2024]
Abstract
Microbial electrosynthesis (MES) is an emerging technology that couples renewable electricity to microbial production processes. Although advances in MES performance have been driven largely by microbial mixed cultures, we see a great limitation in the diversity, and hence value, of products that can be achieved in undefined mixed cultures. By contrast, metabolic control of pure cultures and genetic engineering could greatly expand the scope of MES, and even of broader electrobiotechnology, to include targeted high-value products. To leverage this potential, we advocate for more efforts and activities to develop engineered electroactive microbes for synthesis, and we highlight the need for a standardized electrobioreactor infrastructure that allows the establishment and engineering of electrobioprocesses with these novel biocatalysts.
Collapse
Affiliation(s)
- Falk Harnisch
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research GmbH, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Jörg S Deutzmann
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA
| | - Santiago T Boto
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Adolf Reichwein Strasse 23, 07745 Jena, Germany; Institute of Microbiology, Faculty for Biological Sciences, Friedrich-Schiller-University Jena, Neugasse 23, 07743 Jena, Germany
| | - Miriam A Rosenbaum
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Adolf Reichwein Strasse 23, 07745 Jena, Germany; Institute of Microbiology, Faculty for Biological Sciences, Friedrich-Schiller-University Jena, Neugasse 23, 07743 Jena, Germany.
| |
Collapse
|
3
|
Kelly AR, Glover DJ. Information Transmission through Biotic-Abiotic Interfaces to Restore or Enhance Human Function. ACS APPLIED BIO MATERIALS 2024; 7:3605-3628. [PMID: 38729914 DOI: 10.1021/acsabm.4c00435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
Advancements in reliable information transfer across biotic-abiotic interfaces have enabled the restoration of lost human function. For example, communication between neuronal cells and electrical devices restores the ability to walk to a tetraplegic patient and vision to patients blinded by retinal disease. These impactful medical achievements are aided by tailored biotic-abiotic interfaces that maximize information transfer fidelity by considering the physical properties of the underlying biological and synthetic components. This Review develops a modular framework to define and describe the engineering of biotic and abiotic components as well as the design of interfaces to facilitate biotic-abiotic information transfer using light or electricity. Delineating the properties of the biotic, interface, and abiotic components that enable communication can serve as a guide for future research in this highly interdisciplinary field. Application of synthetic biology to engineer light-sensitive proteins has facilitated the control of neural signaling and the restoration of rudimentary vision after retinal blindness. Electrophysiological methodologies that use brain-computer interfaces and stimulating implants to bypass spinal column injuries have led to the rehabilitation of limb movement and walking ability. Cellular interfacing methodologies and on-chip learning capability have been made possible by organic transistors that mimic the information processing capacity of neurons. The collaboration of molecular biologists, material scientists, and electrical engineers in the emerging field of biotic-abiotic interfacing will lead to the development of prosthetics capable of responding to thought and experiencing touch sensation via direct integration into the human nervous system. Further interdisciplinary research will improve electrical and optical interfacing technologies for the restoration of vision, offering greater visual acuity and potentially color vision in the near future.
Collapse
Affiliation(s)
- Alexander R Kelly
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Dominic J Glover
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| |
Collapse
|
4
|
Wu J, Wu J, He RL, Hu L, Liu DF, Li WW. Modularized Engineering of Shewanella oneidensis MR-1 for Efficient and Directional Synthesis of 5-Aminolevulinic Acid. Metab Eng 2024; 83:206-215. [PMID: 38710300 DOI: 10.1016/j.ymben.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/13/2024] [Accepted: 05/03/2024] [Indexed: 05/08/2024]
Abstract
Shewanella oneidensis MR-1 has found widespread applications in pollutant transformation and bioenergy production, closely tied to its outstanding heme synthesis capabilities. However, this significant biosynthetic potential is still unexploited so far. Here, we turned this bacterium into a highly-efficient bio-factory for green synthesis of 5-Aminolevulinic Acid (5-ALA), an important chemical for broad applications in agriculture, medicine, and the food industries. The native C5 pathway genes of S. oneidensis was employed, together with the introduction of foreign anti-oxidation module, to establish the 5-ALA production module, resulting 87-fold higher 5-ALA yield and drastically enhanced tolerance than the wild type. Furthermore, the metabolic flux was regulated by using CRISPR interference and base editing techniques to suppress the competitive pathways to further improve the 5-ALA titer. The engineered strain exhibited 123-fold higher 5-ALA production capability than the wild type. This study not only provides an appealing new route for 5-ALA biosynthesis, but also presents a multi-dimensional modularized engineering strategy to broaden the application scope of S. oneidensis.
Collapse
Affiliation(s)
- Jie Wu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, 230026, China; Institute of Advanced Technology, University of Science and Technology of China, Hefei, 230000, China
| | - Jing Wu
- School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230026, China
| | - Ru-Li He
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, 230026, China; Institute of Advanced Technology, University of Science and Technology of China, Hefei, 230000, China
| | - Lan Hu
- School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230026, China
| | - Dong-Feng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, 230026, China.
| | - Wen-Wei Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, 230026, China; Institute of Advanced Technology, University of Science and Technology of China, Hefei, 230000, China; School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230026, China.
| |
Collapse
|
5
|
Zhou W, Zhang W, Geng W, Huang Y, Zhang TK, Yi ZQ, Ge Y, Huang Y, Tian G, Yang XY. External Electrons Directly Stimulate Escherichia coli for Enhancing Biological Hydrogen Production. ACS NANO 2024; 18:10840-10849. [PMID: 38616401 DOI: 10.1021/acsnano.4c00619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
External electric field has the potential to influence metabolic processes such as biological hydrogen production in microorganisms. Based on this concept, we designed and constructed an electroactive hybrid system for microbial biohydrogen production under an electric field comprised of polydopamine (PDA)-modified Escherichia coli (E. coli) and Ni foam (NF). In this system, electrons generated from NF directly migrate into E. coli cells to promote highly efficient biocatalytic hydrogen production. Compared to that generated in the absence of electric field stimulation, biohydrogen production by the PDA-modified E. coli-based system is significantly enhanced. This investigation has demonstrated the mechanism for electron transfer in a biohybrid system and gives insight into precise basis for the enhancement of hydrogen production by using the multifield coupling technology.
Collapse
Affiliation(s)
- Wei Zhou
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| | - Wen Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| | - Wei Geng
- School of Chemical Engineering and Technology, Sun Yat-Sen University, 2 Daxue Road, Zhuhai 519082, P. R. China
| | - Yaoqi Huang
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Tong-Kai Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| | - Zi-Qian Yi
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| | - Yang Ge
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| | - Yao Huang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| | - Ge Tian
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| | - Xiao-Yu Yang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory & State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122, Luoshi Road, Wuhan 430070, China
| |
Collapse
|
6
|
Brachi M, El Housseini W, Beaver K, Jadhav R, Dantanarayana A, Boucher DG, Minteer SD. Advanced Electroanalysis for Electrosynthesis. ACS ORGANIC & INORGANIC AU 2024; 4:141-187. [PMID: 38585515 PMCID: PMC10995937 DOI: 10.1021/acsorginorgau.3c00051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 04/09/2024]
Abstract
Electrosynthesis is a popular, environmentally friendly substitute for conventional organic methods. It involves using charge transfer to stimulate chemical reactions through the application of a potential or current between two electrodes. In addition to electrode materials and the type of reactor employed, the strategies for controlling potential and current have an impact on the yields, product distribution, and reaction mechanism. In this Review, recent advances related to electroanalysis applied in electrosynthesis were discussed. The first part of this study acts as a guide that emphasizes the foundations of electrosynthesis. These essentials include instrumentation, electrode selection, cell design, and electrosynthesis methodologies. Then, advances in electroanalytical techniques applied in organic, enzymatic, and microbial electrosynthesis are illustrated with specific cases studied in recent literature. To conclude, a discussion of future possibilities that intend to advance the academic and industrial areas is presented.
Collapse
Affiliation(s)
- Monica Brachi
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112 United States
| | - Wassim El Housseini
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112 United States
| | - Kevin Beaver
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112 United States
| | - Rohit Jadhav
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112 United States
| | - Ashwini Dantanarayana
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112 United States
| | - Dylan G. Boucher
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112 United States
| | - Shelley D. Minteer
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112 United States
- Kummer
Institute Center for Resource Sustainability, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
| |
Collapse
|
7
|
Zhang J, Li F, Liu D, Liu Q, Song H. Engineering extracellular electron transfer pathways of electroactive microorganisms by synthetic biology for energy and chemicals production. Chem Soc Rev 2024; 53:1375-1446. [PMID: 38117181 DOI: 10.1039/d3cs00537b] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The excessive consumption of fossil fuels causes massive emission of CO2, leading to climate deterioration and environmental pollution. The development of substitutes and sustainable energy sources to replace fossil fuels has become a worldwide priority. Bio-electrochemical systems (BESs), employing redox reactions of electroactive microorganisms (EAMs) on electrodes to achieve a meritorious combination of biocatalysis and electrocatalysis, provide a green and sustainable alternative approach for bioremediation, CO2 fixation, and energy and chemicals production. EAMs, including exoelectrogens and electrotrophs, perform extracellular electron transfer (EET) (i.e., outward and inward EET), respectively, to exchange energy with the environment, whose rate determines the efficiency and performance of BESs. Therefore, we review the synthetic biology strategies developed in the last decade for engineering EAMs to enhance the EET rate in cell-electrode interfaces for facilitating the production of electricity energy and value-added chemicals, which include (1) progress in genetic manipulation and editing tools to achieve the efficient regulation of gene expression, knockout, and knockdown of EAMs; (2) synthetic biological engineering strategies to enhance the outward EET of exoelectrogens to anodes for electricity power production and anodic electro-fermentation (AEF) for chemicals production, including (i) broadening and strengthening substrate utilization, (ii) increasing the intracellular releasable reducing equivalents, (iii) optimizing c-type cytochrome (c-Cyts) expression and maturation, (iv) enhancing conductive nanowire biosynthesis and modification, (v) promoting electron shuttle biosynthesis, secretion, and immobilization, (vi) engineering global regulators to promote EET rate, (vii) facilitating biofilm formation, and (viii) constructing cell-material hybrids; (3) the mechanisms of inward EET, CO2 fixation pathway, and engineering strategies for improving the inward EET of electrotrophic cells for CO2 reduction and chemical production, including (i) programming metabolic pathways of electrotrophs, (ii) rewiring bioelectrical circuits for enhancing inward EET, and (iii) constructing microbial (photo)electrosynthesis by cell-material hybridization; (4) perspectives on future challenges and opportunities for engineering EET to develop highly efficient BESs for sustainable energy and chemical production. We expect that this review will provide a theoretical basis for the future development of BESs in energy harvesting, CO2 fixation, and chemical synthesis.
Collapse
Affiliation(s)
- Junqi Zhang
- Frontier Science Center for Synthetic Biology (Ministry of Education), Key Laboratory of Systems Bioengineering, and School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
| | - Feng Li
- Frontier Science Center for Synthetic Biology (Ministry of Education), Key Laboratory of Systems Bioengineering, and School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
| | - Dingyuan Liu
- Frontier Science Center for Synthetic Biology (Ministry of Education), Key Laboratory of Systems Bioengineering, and School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
| | - Qijing Liu
- Frontier Science Center for Synthetic Biology (Ministry of Education), Key Laboratory of Systems Bioengineering, and School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
| | - Hao Song
- Frontier Science Center for Synthetic Biology (Ministry of Education), Key Laboratory of Systems Bioengineering, and School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
| |
Collapse
|
8
|
Ford KC, TerAvest MA. The electron transport chain of Shewanella oneidensis MR-1 can operate bidirectionally to enable microbial electrosynthesis. Appl Environ Microbiol 2024; 90:e0138723. [PMID: 38117056 PMCID: PMC10807441 DOI: 10.1128/aem.01387-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 11/13/2023] [Indexed: 12/21/2023] Open
Abstract
Extracellular electron transfer is a process by which bacterial cells can exchange electrons with a redox-active material located outside of the cell. In Shewanella oneidensis, this process is natively used to facilitate respiration using extracellular electron acceptors such as Fe(III) or an anode. Previously, it was demonstrated that this process can be used to drive the microbial electrosynthesis (MES) of 2,3-butanediol (2,3-BDO) in S. oneidensis exogenously expressing butanediol dehydrogenase (BDH). Electrons taken into the cell from a cathode are used to generate NADH, which in turn is used to reduce acetoin to 2,3-BDO via BDH. However, generating NADH via electron uptake from a cathode is energetically unfavorable, so NADH dehydrogenases couple the reaction to proton motive force. We therefore need to maintain the proton gradient across the membrane to sustain NADH production. This work explores accomplishing this task by bidirectional electron transfer, where electrons provided by the cathode go to both NADH formation and oxygen (O2) reduction by oxidases. We show that oxidases use trace dissolved oxygen in a microaerobic bioelectrical chemical system (BES), and the translocation of protons across the membrane during O2 reduction supports 2,3-BDO generation. Interestingly, this process is inhibited by high levels of dissolved oxygen in this system. In an aerated BES, O2 molecules react with the strong reductant (cathode) to form reactive oxygen species, resulting in cell death.IMPORTANCEMicrobial electrosynthesis (MES) is increasingly employed for the generation of specialty chemicals, such as biofuels, bioplastics, and cancer therapeutics. For these systems to be viable for industrial scale-up, it is important to understand the energetic requirements of the bacteria to mitigate unnecessary costs. This work demonstrates sustained production of an industrially relevant chemical driven by a cathode. Additionally, it optimizes a previously published system by removing any requirement for phototrophic energy, thereby removing the additional cost of providing a light source. We also demonstrate the severe impact of oxygen intrusion into bioelectrochemical systems, offering insight to future researchers aiming to work in an anaerobic environment. These studies provide insight into both the thermodynamics of electrosynthesis and the importance of the bioelectrochemical systems' design.
Collapse
Affiliation(s)
- Kathryne C. Ford
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Michaela A. TerAvest
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| |
Collapse
|
9
|
Tu W, Xu J, Thompson IP, Huang WE. Engineering artificial photosynthesis based on rhodopsin for CO 2 fixation. Nat Commun 2023; 14:8012. [PMID: 38049399 PMCID: PMC10696030 DOI: 10.1038/s41467-023-43524-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 11/11/2023] [Indexed: 12/06/2023] Open
Abstract
Microbial rhodopsin, a significant contributor to sustaining life through light harvesting, holds untapped potential for carbon fixation. Here, we construct an artificial photosynthesis system which combines the proton-pumping ability of rhodopsin with an extracellular electron uptake mechanism, establishing a pathway to drive photoelectrosynthetic CO2 fixation by Ralstonia eutropha (also known as Cupriavidus necator) H16, a facultatively chemolithoautotrophic soil bacterium. R. eutropha is engineered to heterologously express an extracellular electron transfer pathway of Shewanella oneidensis MR-1 and Gloeobacter rhodopsin (GR). Employing GR and the outer-membrane conduit MtrCAB from S. oneidensis, extracellular electrons and GR-driven proton motive force are integrated into R. eutropha's native electron transport chain (ETC). Inspired by natural photosynthesis, the photoelectrochemical system splits water to supply electrons to R. eutropha via the Mtr outer-membrane route. The light-activated proton pump - GR, supported by canthaxanthin as an antenna, powers ATP synthesis and reverses the ETC to regenerate NADH/NADPH, facilitating R. eutropha's biomass synthesis from CO2. Overexpression of a carbonic anhydrase further enhances CO2 fixation. This artificial photosynthesis system has the potential to advance the development of efficient photosynthesis, redefining our understanding of the ecological role of microbial rhodopsins in nature.
Collapse
Affiliation(s)
- Weiming Tu
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK
| | - Jiabao Xu
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK
| | - Ian P Thompson
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK
| | - Wei E Huang
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK.
| |
Collapse
|
10
|
Li Y, Luo Q, Su J, Dong G, Cao M, Wang Y. Metabolic regulation of Shewanella oneidensis for microbial electrosynthesis: From extracellular to intracellular. Metab Eng 2023; 80:1-11. [PMID: 37673324 DOI: 10.1016/j.ymben.2023.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/09/2023] [Accepted: 08/27/2023] [Indexed: 09/08/2023]
Abstract
Shewanella oneidensis MR-1 (S. oneidensis MR-1) has been shown to benefit from microbial electrosynthesis (MES) due to its exceptional electron transfer efficiency. In this study, genes involved in both extracellular electron uptake (EEU) and intracellular CO2 conversion processes were examined and regulated to enhance MES performance. The key genes identified for MES in the EEU process were mtrB, mtrC, mtrD, mtrE, omcA and cctA. Overexpression of these genes resulted in 1.5-2.1 times higher formate productivity than that of the wild-type strains (0.63 mmol/(L·μg protein)), as 0.94-1.61 mmol/(L·μg protein). In the intracellular CO2 conversion process, overexpression of the nadE, nadD, nadR, nadV, pncC and petC genes increased formate productivity 1.3-fold-3.4-fold. Moreover, overexpression of the formate dehydrogenase genes fdhA1, fdhB1 and fdhX1 in modified strains led to a 2.3-fold-3.1-fold increase in formate productivity compared to wild-type strains. The co-overexpression of cctA, fdhA1 and nadV in the mutant strain resulted in 5.59 times (3.50 mmol/(L·μg protein)) higher formate productivity than that of the wild-type strains. These findings revealed that electrons of MES derived from the electrode were utilized in the energy module for synthesizing ATP and NADH, followed by the synthesis of formate in formate dehydrogenase by the combinatorial effects of ATP, NADH, electrons and CO2. The results provide new insights into the mechanism of MES in S. oneidensis MR-1 and pave the way for genetic improvements that could facilitate the further application of MES.
Collapse
Affiliation(s)
- Yixin Li
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen, 361005, China
| | - Qingliu Luo
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Jiaying Su
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen, 361005, China; School of Resource and Chemical Engineering, Sanming University, Sanming, 365004, China
| | - Guowen Dong
- School of Resource and Chemical Engineering, Sanming University, Sanming, 365004, China
| | - Mingfeng Cao
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen, 361005, China.
| | - Yuanpeng Wang
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen, 361005, China.
| |
Collapse
|
11
|
Wu T, Liu Y, Zheng T, Dai Y, Li Z, Lin D. Fe-Based Nanomaterials and Plant Growth Promoting Rhizobacteria Synergistically Degrade Polychlorinated Biphenyls by Producing Extracellular Reactive Oxygen Species. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:12771-12781. [PMID: 37583057 DOI: 10.1021/acs.est.3c02495] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
Plant growth promoting rhizobacteria (PGPR) produce extracellular reactive oxygen species (ROS) to protect plants from external stresses. Fe-based nanomaterials can potentially interact with PGPR and synergistically degrade organic pollutants, yet they have received no study. Here, we studied how the interaction between a typical PGPR (Pseudomonas chlororaphis, JD37) and Fe-based nanomaterials facilitated the degradation of 2,4,4'-trichlorobiphenyl (PCB28), by comparing the zerovalent iron of 20 nm (nZVI20), 100 nm (nZVI100), and 5 μm; iron oxide nanomaterials (α-Fe2O3, γ-Fe2O3, and Fe3O4) of ca. 20 nm; and ferrous and ferric salts. Although all Fe materials (0.1 g L-1) alone could not degrade aqueous PCB28 (0.1 mg L-1) under dark or aerobic conditions, nZVI20, nZVI100, α-Fe2O3, and Fe2+ promoted PCB28 degradation by JD37, with the half-life of PCB28 shortened from 16.5 h by JD37 alone to 8.1 h with nZVI100 cotreatment. Mechanistically, the nanomaterials stimulated JD37 to secrete phenazine-1-carboxylic acid and accelerated the NADH/NAD+ conversion, promoting O2*- generation; JD37 increased Fe(II) dissolution from the nanomaterials, facilitating *OH generation; and the ROS gradually degraded PCB28 into benzoic acid through dihydroxy substitution, oxidation to quinone, and Michael addition. These findings provide a new strategy of nanoenabled biodegradation of organic pollutants by applying Fe-based nanomaterials and PGPR.
Collapse
Affiliation(s)
- Ting Wu
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, P. R. China
- Xi'an Center, China Geological Survey, Ministry of Natural Resources, Xi'an 710119, P. R. China
| | - Yangzhi Liu
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, P. R. China
| | - Tianying Zheng
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, P. R. China
| | - Yunbu Dai
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, P. R. China
| | - Zhongyu Li
- Xi'an Center, China Geological Survey, Ministry of Natural Resources, Xi'an 710119, P. R. China
| | - Daohui Lin
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, P. R. China
- Zhejiang Ecological Civilization Academy, Anji 313300, P. R. China
| |
Collapse
|
12
|
Ikeda S, Tomita K, Nakagawa G, Kouzuma A, Watanabe K. Supplementation with Amino Acid Sources Facilitates Fermentative Growth of Shewanella oneidensis MR-1 in Defined Media. Appl Environ Microbiol 2023; 89:e0086823. [PMID: 37367298 PMCID: PMC10370299 DOI: 10.1128/aem.00868-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 06/04/2023] [Indexed: 06/28/2023] Open
Abstract
Shewanella oneidensis MR-1 is a facultative anaerobe that grows by respiration using a variety of electron acceptors. This organism serves as a model to study how bacteria thrive in redox-stratified environments. A glucose-utilizing engineered derivative of MR-1 has been reported to be unable to grow in glucose minimal medium (GMM) in the absence of electron acceptors, despite this strain having a complete set of genes for reconstructing glucose to lactate fermentative pathways. To gain insights into why MR-1 is incapable of fermentative growth, this study examined a hypothesis that this strain is programmed to repress the expression of some carbon metabolic genes in the absence of electron acceptors. Comparative transcriptomic analyses of the MR-1 derivative were conducted in the presence and absence of fumarate as an electron acceptor, and these found that the expression of many genes involved in carbon metabolism required for cell growth, including several tricarboxylic acid (TCA) cycle genes, was significantly downregulated in the absence of fumarate. This finding suggests a possibility that MR-1 is unable to grow fermentatively on glucose in minimal media owing to the shortage of nutrients essential for cell growth, such as amino acids. This idea was demonstrated in subsequent experiments that showed that the MR-1 derivative fermentatively grows in GMM containing tryptone or a defined mixture of amino acids. We suggest that gene regulatory circuits in MR-1 are tuned to minimize energy consumption under electron acceptor-depleted conditions, and that this results in defective fermentative growth in minimal media. IMPORTANCE It is an enigma why S. oneidensis MR-1 is incapable of fermentative growth despite having complete sets of genes for reconstructing fermentative pathways. Understanding the molecular mechanisms behind this defect will facilitate the development of novel fermentation technologies for the production of value-added chemicals from biomass feedstocks, such as electro-fermentation. The information provided in this study will also improve our understanding of the ecological strategies of bacteria living in redox-stratified environments.
Collapse
Affiliation(s)
- Sota Ikeda
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Keisuke Tomita
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Gen Nakagawa
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Atsushi Kouzuma
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Kazuya Watanabe
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| |
Collapse
|
13
|
Klein EM, Knoll MT, Gescher J. Microbe-Anode Interactions: Comparing the impact of genetic and material engineering approaches to improve the performance of microbial electrochemical systems (MES). Microb Biotechnol 2023; 16:1179-1202. [PMID: 36808480 PMCID: PMC10221544 DOI: 10.1111/1751-7915.14236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 01/30/2023] [Accepted: 02/02/2023] [Indexed: 02/20/2023] Open
Abstract
Microbial electrochemical systems (MESs) are a highly versatile platform technology with a particular focus on power or energy production. Often, they are used in combination with substrate conversion (e.g., wastewater treatment) and production of value-added compounds via electrode-assisted fermentation. This rapidly evolving field has seen great improvements both technically and biologically, but this interdisciplinarity sometimes hampers overseeing strategies to increase process efficiency. In this review, we first briefly summarize the terminology of the technology and outline the biological background that is essential for understanding and thus improving MES technology. Thereafter, recent research on improvements at the biofilm-electrode interface will be summarized and discussed, distinguishing between biotic and abiotic approaches. The two approaches are then compared, and resulting future directions are discussed. This mini-review therefore provides basic knowledge of MES technology and the underlying microbiology in general and reviews recent improvements at the bacteria-electrode interface.
Collapse
Affiliation(s)
- Edina M. Klein
- Institute of Technical MicrobiologyUniversity of Technology HamburgHamburgGermany
| | - Melanie T. Knoll
- Institute of Technical MicrobiologyUniversity of Technology HamburgHamburgGermany
| | - Johannes Gescher
- Institute of Technical MicrobiologyUniversity of Technology HamburgHamburgGermany
| |
Collapse
|
14
|
Tefft NM, Ford K, TerAvest MA. NADH dehydrogenases drive inward electron transfer in Shewanella oneidensis MR-1. Microb Biotechnol 2023; 16:560-568. [PMID: 36420671 PMCID: PMC9948175 DOI: 10.1111/1751-7915.14175] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 10/17/2022] [Accepted: 10/31/2022] [Indexed: 11/25/2022] Open
Abstract
Shewanella oneidensis MR-1 is a promising chassis organism for microbial electrosynthesis because it has a well-defined biochemical pathway (the Mtr pathway) that can connect extracellular electrodes to respiratory electron carriers inside the cell. We previously found that the Mtr pathway can be used to transfer electrons from a cathode to intracellular electron carriers and drive reduction reactions. In this work, we hypothesized that native NADH dehydrogenases form an essential link between the Mtr pathway and NADH in the cytoplasm. To test this hypothesis, we compared the ability of various mutant strains to accept electrons from a cathode and transfer them to an NADH-dependent reaction in the cytoplasm, reduction of acetoin to 2,3-butanediol. We found that deletion of genes encoding NADH dehydrogenases from the genome blocked electron transfer from a cathode to NADH in the cytoplasm, preventing the conversion of acetoin to 2,3-butanediol. However, electron transfer to fumarate was not blocked by the gene deletions, indicating that NADH dehydrogenase deletion specifically impacted NADH generation and did not cause a general defect in extracellular electron transfer. Proton motive force (PMF) is linked to the function of the NADH dehydrogenases. We added a protonophore to collapse PMF and observed that it blocked inward electron transfer to acetoin but not fumarate. Together these results indicate a link between the Mtr pathway and intracellular NADH. Future work to optimize microbial electrosynthesis in S. oneidensis MR-1 should focus on optimizing flux through NADH dehydrogenases.
Collapse
Affiliation(s)
- Nicholas M Tefft
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Kathryne Ford
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA.,Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Michaela A TerAvest
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| |
Collapse
|
15
|
Tu W, Huang WE. Rhodopsin driven microbial CO 2 fixation using synthetic biology design. Environ Microbiol 2023; 25:126-130. [PMID: 36221243 PMCID: PMC10092888 DOI: 10.1111/1462-2920.16243] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 10/09/2022] [Indexed: 01/21/2023]
Affiliation(s)
- Weiming Tu
- Department of Engineering ScienceUniversity of OxfordOxfordUK
| | - Wei E. Huang
- Department of Engineering ScienceUniversity of OxfordOxfordUK
| |
Collapse
|
16
|
Deciphering Molecular Factors That Affect Electron Transfer at the Cell Surface of Electroactive Bacteria: The Case of OmcA from Shewanella oneidensis MR-1. Microorganisms 2022; 11:microorganisms11010079. [PMID: 36677373 PMCID: PMC9861303 DOI: 10.3390/microorganisms11010079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/23/2022] [Accepted: 12/24/2022] [Indexed: 12/29/2022] Open
Abstract
Multiheme cytochromes play a central role in extracellular electron transfer, a process that allows microorganisms to sustain their metabolism with external electron acceptors or donors. In Shewanella oneidensis MR-1, the decaheme cytochromes OmcA and MtrC show functional specificity for interaction with soluble and insoluble redox partners. In this work, the capacity of extracellular electron transfer by mutant variants of S. oneidensis MR-1 OmcA was investigated. The results show that amino acid mutations can affect protein stability and alter the redox properties of the protein, without affecting the ability to perform extracellular electron transfer to methyl orange dye or a poised electrode. The results also show that there is a good correlation between the reduction of the dye and the current generated at the electrode for most but not all mutants. This observation opens the door for investigations of the molecular mechanisms of interaction with different electron acceptors to tailor these surface exposed cytochromes towards specific bio-based applications.
Collapse
|
17
|
Davison PA, Tu W, Xu J, Della Valle S, Thompson IP, Hunter CN, Huang WE. Engineering a Rhodopsin-Based Photo-Electrosynthetic System in Bacteria for CO 2 Fixation. ACS Synth Biol 2022; 11:3805-3816. [PMID: 36264158 PMCID: PMC9680020 DOI: 10.1021/acssynbio.2c00397] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A key goal of synthetic biology is to engineer organisms that can use solar energy to convert CO2 to biomass, chemicals, and fuels. We engineered a light-dependent electron transfer chain by integrating rhodopsin and an electron donor to form a closed redox loop, which drives rhodopsin-dependent CO2 fixation. A light-driven proton pump comprising Gloeobacter rhodopsin (GR) and its cofactor retinal have been assembled in Ralstonia eutropha (Cupriavidus necator) H16. In the presence of light, this strain fixed inorganic carbon (or bicarbonate) leading to 20% growth enhancement, when formate was used as an electron donor. We found that an electrode from a solar panel can replace organic compounds to serve as the electron donor, mediated by the electron shuttle molecule riboflavin. In this new autotrophic and photo-electrosynthetic system, GR is augmented by an external photocell for reductive CO2 fixation. We demonstrated that this hybrid photo-electrosynthetic pathway can drive the engineered R. eutropha strain to grow using CO2 as the sole carbon source. In this system, a bioreactor with only two inputs, light and CO2, enables the R. eutropha strain to perform a rhodopsin-dependent autotrophic growth. Light energy alone, supplied by a solar panel, can drive the conversion of CO2 into biomass with a maximum electron transfer efficiency of 20%.
Collapse
Affiliation(s)
- Paul A. Davison
- Plants,
Photosynthesis and Soil, School of Biosciences, University of Sheffield, SheffieldS10 2TN, United Kingdom
| | - Weiming Tu
- Department
of Engineering Science, University of Oxford, OxfordOX1 3PJ, United Kingdom
| | - Jiabao Xu
- Department
of Engineering Science, University of Oxford, OxfordOX1 3PJ, United Kingdom
| | - Simona Della Valle
- Department
of Engineering Science, University of Oxford, OxfordOX1 3PJ, United Kingdom
| | - Ian P. Thompson
- Department
of Engineering Science, University of Oxford, OxfordOX1 3PJ, United Kingdom
| | - C. Neil Hunter
- Plants,
Photosynthesis and Soil, School of Biosciences, University of Sheffield, SheffieldS10 2TN, United Kingdom
| | - Wei E. Huang
- Department
of Engineering Science, University of Oxford, OxfordOX1 3PJ, United Kingdom,. Tel: +44 1865 283786
| |
Collapse
|
18
|
Ford K, Kaste JAM, Shachar-Hill Y, TerAvest MA. Flux-Balance Analysis and Mobile CRISPRi-Guided Deletion of a Conditionally Essential Gene in Shewanella oneidensis MR-1. ACS Synth Biol 2022; 11:3405-3413. [PMID: 36219726 PMCID: PMC9595118 DOI: 10.1021/acssynbio.2c00323] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Indexed: 01/24/2023]
Abstract
Carbon-neutral production of valuable bioproducts is critical to sustainable development but remains limited by the slow engineering of photosynthetic organisms. Improving existing synthetic biology tools to engineer model organisms to fix carbon dioxide is one route to overcoming the limitations of photosynthetic organisms. In this work, we describe a pipeline that enabled the deletion of a conditionally essential gene from the Shewanella oneidensis MR-1 genome. S. oneidensis is a simple bacterial host that could be used for electricity-driven conversion of carbon dioxide in the future with further genetic engineering. We used Flux Balance Analysis (FBA) to model carbon and energy flows in central metabolism and assess the effects of single and double gene deletions. We modeled the growth of deletion strains under several alternative conditions to identify substrates that restore viability to an otherwise lethal gene knockout. These predictions were tested in vivo using a Mobile-CRISPRi gene knockdown system. The information learned from FBA and knockdown experiments informed our strategy for gene deletion, allowing us to successfully delete an "expected essential" gene, gpmA. FBA predicted, knockdown experiments supported, and deletion confirmed that the "essential" gene gpmA is not needed for survival, dependent on the medium used. Removal of gpmA is a first step toward driving electrode-powered CO2 fixation via RuBisCO. This work demonstrates the potential for broadening the scope of genetic engineering in S. oneidensis as a synthetic biology chassis. By combining computational analysis with a CRISPRi knockdown system in this way, one can systematically assess the impact of conditionally essential genes and use this knowledge to generate mutations previously thought unachievable.
Collapse
Affiliation(s)
- Kathryne
C. Ford
- Department
of Biochemistry and Molecular Biology, Michigan
State University, East Lansing, Michigan 48824, United States
- Department
of Microbiology and Molecular Genetics, Michigan State University, East
Lansing, Michigan 48824, United States
| | - Joshua A. M. Kaste
- Department
of Biochemistry and Molecular Biology, Michigan
State University, East Lansing, Michigan 48824, United States
- Department
of Plant Biology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Yair Shachar-Hill
- Department
of Plant Biology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Michaela A. TerAvest
- Department
of Biochemistry and Molecular Biology, Michigan
State University, East Lansing, Michigan 48824, United States
| |
Collapse
|
19
|
Sriram S, Wong JWC, Pradhan N. Recent advances in electro-fermentation technology: A novel approach towards balanced fermentation. BIORESOURCE TECHNOLOGY 2022; 360:127637. [PMID: 35853590 DOI: 10.1016/j.biortech.2022.127637] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 07/11/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
Biotransformation of organic substrates via acidogenic fermentation (AF) to high-value products such as C1-C6 carboxylic acids and alcohol serves as platform chemicals for various industrial applications. However, the AF technology suffers from low product titers due to thermodynamic constraints. Recent studies suggest that augmenting AF redox potential can regulate the metabolic pathway and provide seamless electron flow by lowering the activation energy barrier, thus positively influencing the substrate utilization rate, product yield, and speciation. Hence, the augmented AF system with an exogenous electricity supply is termed as electro-fermentation (EF), which has enormous potential to strengthen the fermentation technology domain. Therefore, this critical review systematically discusses the current understanding of EF with a special focus on the extracellular electron transfer mechanism of electroactive bacteria and provides perspectives and research gaps to further improve the technology for green chemical synthesis, sustainable waste management, and circular bio-economy.
Collapse
Affiliation(s)
- Saranya Sriram
- Department of Biology, Faculty of Science, Hong Kong Baptist University, Hong Kong, SAR
| | - Jonathan W C Wong
- Department of Biology, Faculty of Science, Hong Kong Baptist University, Hong Kong, SAR; Institute of Bioresource and Agriculture, Hong Kong Baptist University, Kowloon Tong, Hong Kong, SAR.
| | - Nirakar Pradhan
- Department of Biology, Faculty of Science, Hong Kong Baptist University, Hong Kong, SAR; Institute of Bioresource and Agriculture, Hong Kong Baptist University, Kowloon Tong, Hong Kong, SAR.
| |
Collapse
|
20
|
Wang Z, Bai H, Yu W, Gao Z, Chen W, Yang Z, Zhu C, Huang Y, Lv F, Wang S. Flexible bioelectronic device fabricated by conductive polymer-based living material. SCIENCE ADVANCES 2022; 8:eabo1458. [PMID: 35731871 PMCID: PMC9216517 DOI: 10.1126/sciadv.abo1458] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/06/2022] [Indexed: 05/26/2023]
Abstract
Living materials are worked as an inside collaborative system that could naturally respond to changing environmental conditions. The regulation of bioelectronic processes in living materials could be effective for collecting biological signals and detecting biomarkers. Here, we constructed a living material with conjugated polymers poly[3-(3'-N,N,N-triethylamino-1'-propyloxy)-4-methyl-2,5-thiophene chloride] (PMNT) and Shewanella oneidensis MR-1 biofilm. In addition, the living material was integrated as a flexible bioelectronic device for lactate detection in physiological fluids (sweat, urine, and plasma). Owing to the electroconductivity of conjugated polymers, PMNT could optimize the bioelectronic process in the living material. The collected electrical signal could be wirelessly transferred to a portable smartphone for reading and analyzing. Because lactate is also a biomarker for cancer treatment, the flexible bioelectronic device was further used to detect and count the cancer cells. The proof of the bioelectronic device using conductive polymer-based living material exhibits promising applications in the next-generation personal health monitoring systems.
Collapse
Affiliation(s)
- Zenghao Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Haotian Bai
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
| | - Wen Yu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Zhiqiang Gao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Weijian Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
| | - Zhiwen Yang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chuanwei Zhu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yiming Huang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
| | - Fengting Lv
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
| | - Shu Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100910, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| |
Collapse
|
21
|
Davenport EJ, Bose A. Taxonomic Re-Evaluation and Genomic Comparison of Novel Extracellular Electron Uptake-Capable Rhodovulum visakhapatnamense and Rhodovulum sulfidophilum Isolates. Microorganisms 2022; 10:1235. [PMID: 35744753 PMCID: PMC9230146 DOI: 10.3390/microorganisms10061235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/14/2022] [Accepted: 06/15/2022] [Indexed: 11/28/2022] Open
Abstract
Rhodovulum spp. are anoxygenic phototrophic purple bacteria with versatile metabolisms, including the ability to obtain electrons from minerals in their environment to drive photosynthesis, a relatively novel process called phototrophic extracellular electron uptake (pEEU). A total of 15 strains of Rhodovulum sulfidophilum were isolated from a marine estuary to observe these metabolisms in marine phototrophs. One representative strain, Rhodovulum sulfidophilum strain AB26, can perform phototrophic iron oxidation (photoferrotrophy) and couples carbon dioxide fixation to pEEU. Here, we reclassify two R. sulfidophilum isolates, strainAB26 and strain AB19, as Rhodovulum visakhapatnamense using taxonomic re-evaluation based on 16S and pufM phylogenetic analyses. The strain AB26 genome consists of 4,380,746 base-pairs, including two plasmids, and encodes 4296 predicted protein-coding genes. Strain AB26 contains 22 histidine kinases, 20 response regulators, and dedicates ~16% of its genome to transport. Transcriptomic data under aerobic, photoheterotrophy, photoautotrophy, and pEEU reveals how gene expression varies between metabolisms in a novel R. visakhapatnamense strain. Genome comparison led by transcriptomic data under pEEU reveals potential pEEU-relevant genes both unique to R. visakhapatnamense strains and shared within the R. sulfidophilum genomes. With these data we identify potential pEEU-important transcripts and how speciation may affect molecular mechanisms of pEEU in Rhodovulum species from the same environment.
Collapse
Affiliation(s)
| | - Arpita Bose
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA;
| |
Collapse
|
22
|
Chen Z, Zhang J, Lyu Q, Wang H, Ji X, Yan Z, Chen F, Dahlgren RA, Zhang M. Modular configurations of living biomaterials incorporating nano-based artificial mediators and synthetic biology to improve bioelectrocatalytic performance: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 824:153857. [PMID: 35176368 DOI: 10.1016/j.scitotenv.2022.153857] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/24/2022] [Accepted: 02/09/2022] [Indexed: 06/14/2023]
Abstract
Currently, the industrial application of bioelectrochemical systems (BESs) that are incubated with natural electrochemically active microbes (EABs) is limited due to inefficient extracellular electron transfer (EET) by natural EABs. Notably, recent studies have identified several novel living biomaterials comprising highly efficient electron transfer systems allowing unparalleled proficiency of energy conversion. Introduction of these biomaterials into BESs could fundamentally increase their utilization for a wide range of applications. This review provides a comprehensive assessment of recent advancements in the design of living biomaterials that can be exploited to enhance bioelectrocatalytic performance. Further, modular configurations of abiotic and biotic components promise a powerful enhancement through integration of nano-based artificial mediators and synthetic biology. Herein, recent advancements in BESs are synthesized and assessed, including heterojunctions between conductive nanomaterials and EABs, in-situ hybrid self-assembly of EABs and nano-sized semiconductors, cytoprotection in biohybrids, synthetic biological modifications of EABs and electroactive biofilms. Since living biomaterials comprise a broad range of disciplines, such as molecular biology, electrochemistry and material sciences, full integration of technological advances applied in an interdisciplinary framework will greatly enhance/advance the utility and novelty of BESs. Overall, emerging fundamental knowledge concerning living biomaterials provides a powerful opportunity to markedly boost EET efficiency and facilitate the industrial application of BESs to meet global sustainability challenges/goals.
Collapse
Affiliation(s)
- Zheng Chen
- School of Public Health and Management, Wenzhou Medical University, Wenzhou 325035, People's Republic of China; School of Environmental Science & Engineering, Tan Kah Kee College, Xiamen University, Zhangzhou 363105, People's Republic of China; Fujian Provincial Key Lab of Coastal Basin Environment, Fujian Polytechnic Normal University, Fuqing 350300, People's Republic of China.
| | - Jing Zhang
- School of Environmental Science & Engineering, Tan Kah Kee College, Xiamen University, Zhangzhou 363105, People's Republic of China
| | - Qingyang Lyu
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, People's Republic of China
| | - Honghui Wang
- School of Environmental Science & Engineering, Tan Kah Kee College, Xiamen University, Zhangzhou 363105, People's Republic of China
| | - Xiaoliang Ji
- School of Public Health and Management, Wenzhou Medical University, Wenzhou 325035, People's Republic of China
| | - Zhiying Yan
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, People's Republic of China
| | - Fang Chen
- Fujian Provincial Key Lab of Coastal Basin Environment, Fujian Polytechnic Normal University, Fuqing 350300, People's Republic of China
| | - Randy A Dahlgren
- School of Public Health and Management, Wenzhou Medical University, Wenzhou 325035, People's Republic of China; Department of Land, Air and Water Resources, University of California, Davis, CA 95616, USA
| | - Minghua Zhang
- School of Public Health and Management, Wenzhou Medical University, Wenzhou 325035, People's Republic of China; Department of Land, Air and Water Resources, University of California, Davis, CA 95616, USA
| |
Collapse
|
23
|
Luo J, Yuan Q, Mao Y, Wei F, Zhao J, Yu W, Kong S, Guo Y, Cai J, Liao X, Wang Z, Ma H. Reconstruction of a Genome-Scale Metabolic Network for Shewanella oneidensis MR-1 and Analysis of its Metabolic Potential for Bioelectrochemical Systems. Front Bioeng Biotechnol 2022; 10:913077. [PMID: 35646853 PMCID: PMC9133699 DOI: 10.3389/fbioe.2022.913077] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 04/26/2022] [Indexed: 11/28/2022] Open
Abstract
Bioelectrochemical systems (BESs) based on Shewanella oneidensis MR-1 offer great promise for sustainable energy/chemical production, but the low rate of electron generation remains a crucial bottleneck preventing their industrial application. Here, we reconstructed a genome-scale metabolic model of MR-1 to provide a strong theoretical basis for novel BES applications. The model iLJ1162, comprising 1,162 genes, 1,818 metabolites and 2,084 reactions, accurately predicted cellular growth using a variety of substrates with 86.9% agreement with experimental results, which is significantly higher than the previously published models iMR1_799 and iSO783. The simulation of microbial fuel cells indicated that expanding the substrate spectrum of MR-1 to highly reduced feedstocks, such as glucose and glycerol, would be beneficial for electron generation. In addition, 31 metabolic engineering targets were predicted to improve electricity production, three of which have been experimentally demonstrated, while the remainder are potential targets for modification. Two potential electron transfer pathways were identified, which could be new engineering targets for increasing the electricity production capacity of MR-1. Finally, the iLJ1162 model was used to simulate the optimal biosynthetic pathways for six platform chemicals based on the MR-1 chassis in microbial electrosynthesis systems. These results offer guidance for rational design of novel BESs.
Collapse
Affiliation(s)
- Jiahao Luo
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Frontier Science Center for Synthetic Biology (Ministry of Education), Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Qianqian Yuan
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Yufeng Mao
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Fan Wei
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Juntao Zhao
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Frontier Science Center for Synthetic Biology (Ministry of Education), Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Wentong Yu
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Frontier Science Center for Synthetic Biology (Ministry of Education), Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Shutian Kong
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Frontier Science Center for Synthetic Biology (Ministry of Education), Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Yanmei Guo
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jingyi Cai
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Xiaoping Liao
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Zhiwen Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Frontier Science Center for Synthetic Biology (Ministry of Education), Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- *Correspondence: Zhiwen Wang, ; Hongwu Ma,
| | - Hongwu Ma
- Biodesign Center, Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- *Correspondence: Zhiwen Wang, ; Hongwu Ma,
| |
Collapse
|
24
|
Han HX, Tian LJ, Liu DF, Yu HQ, Sheng GP, Xiong Y. Reversing Electron Transfer Chain for Light-Driven Hydrogen Production in Biotic-Abiotic Hybrid Systems. J Am Chem Soc 2022; 144:6434-6441. [PMID: 35377628 DOI: 10.1021/jacs.2c00934] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The biotic-abiotic photosynthetic system integrating inorganic light absorbers with whole-cell biocatalysts innovates the way for sustainable solar-driven chemical transformation. Fundamentally, the electron transfer at the biotic-abiotic interface, which may induce biological response to photoexcited electron stimuli, plays an essential role in solar energy conversion. Herein, we selected an electro-active bacterium Shewanella oneidensis MR-1 as a model, which constitutes a hybrid photosynthetic system with a self-assembled CdS semiconductor, to demonstrate unique biotic-abiotic interfacial behavior. The photoexcited electrons from CdS nanoparticles can reverse the extracellular electron transfer (EET) chain within S. oneidensis MR-1, realizing the activation of a bacterial catalytic network with light illumination. As compared with bare S. oneidensis MR-1, a significant upregulation of hydrogen yield (711-fold), ATP, and reducing equivalent (NADH/NAD+) was achieved in the S. oneidensis MR-1-CdS under visible light. This work sheds light on the fundamental mechanism and provides design guidelines for biotic-abiotic photosynthetic systems.
Collapse
Affiliation(s)
- He-Xing Han
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Li-Jiao Tian
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China
| | - Dong-Feng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Guo-Ping Sheng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Yujie Xiong
- School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| |
Collapse
|
25
|
Harnessing electrical-to-biochemical conversion for microbial synthesis. Curr Opin Biotechnol 2022; 75:102687. [PMID: 35104718 DOI: 10.1016/j.copbio.2022.102687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/18/2021] [Accepted: 01/10/2022] [Indexed: 11/23/2022]
Abstract
Electrical-to-biochemical conversion (E2BC) drives cell metabolism for biosynthesis and has become a promising way to realize green biomanufacturing. This review discusses the following aspects: 1. the natural E2BC processes and their underlying E2BC mechanism; 2. development of artificial E2BC for tunable microbial electrosynthesis; 3. design of electrobiochemical systems using self-powered, light-assisted, and nano-biohybrid approaches; 4. synthetic biology methods for efficient microbial electrosynthesis. This review also compares E2BC with electrocatalysis-biochemical conversion (EC2BC), as both strategies may lead to future carbon negative green biomanufacturing.
Collapse
|
26
|
Yamada S, Takamatsu Y, Ikeda S, Kouzuma A, Watanabe K. Towards Application of Electro-Fermentation for the Production of Value-Added Chemicals From Biomass Feedstocks. Front Chem 2022; 9:805597. [PMID: 35127650 PMCID: PMC8807546 DOI: 10.3389/fchem.2021.805597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 12/24/2021] [Indexed: 12/03/2022] Open
Abstract
According to recent social demands for sustainable developments, the value of biomass as feedstocks for chemical industry is increasing. With the aid of metabolic engineering and genome editing, microbial fermentation has been developed for producing value-added chemicals from biomass feedstocks, while further improvements are desired for producing more diverse chemicals and increasing the production efficiency. The major intrinsic limitation in conventional fermentation technologies is associated with the need for balancing the net redox equivalents between substrates and products, resulting in limited repertories of fermentation products. One solution for this limitation would be “electro-fermentation (EF)” that utilizes bioelectrochemical systems for modifying the intracellular redox state of electrochemically active bacteria, thereby overcoming the redox constraint of fermentation. Recent studies have attempted the production of chemicals based on the concept of EF, while its utility has not been sufficiently demonstrated in terms of low production efficiencies. Here we discuss EF in terms of its concept, current status and future directions, which help us develop its practical applications to sustainable chemical industries.
Collapse
|
27
|
Finkelstein J, Swartz J, Koffas M. Bioelectrosynthesis systems. Curr Opin Biotechnol 2021; 74:211-219. [PMID: 34979469 DOI: 10.1016/j.copbio.2021.11.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/19/2021] [Accepted: 11/25/2021] [Indexed: 11/16/2022]
Abstract
Bioelectrosynthesis (BES) systems exploit extracellular electron transport pathways to augment cellular metabolism. This strategy can be used to improve the economic viability of bio-based syntheses versus conventional methods, most notably petrochemical-based syntheses. It also has the potential to reduce the carbon footprint of biomanufacturing processes. Efficient channeling of cathode-derived electrons towards biosynthesis requires a better understanding of the biological mechanisms of electron transport as well as detailed evaluation of all aspects of process performance. More advanced solutions may deploy cell free systems that use ex situ generated reducing equivalents to improve economic performance.
Collapse
Affiliation(s)
- Joshua Finkelstein
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - James Swartz
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
| | - Mattheos Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA; Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
| |
Collapse
|
28
|
Sundaresan V, Do H, Shrout JD, Bohn PW. Electrochemical and spectroelectrochemical characterization of bacteria and bacterial systems. Analyst 2021; 147:22-34. [PMID: 34874024 PMCID: PMC8791413 DOI: 10.1039/d1an01954f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Microbes, such as bacteria, can be described, at one level, as small, self-sustaining chemical factories. Based on the species, strain, and even the environment, bacteria can be useful, neutral or pathogenic to human life, so it is increasingly important that we be able to characterize them at the molecular level with chemical specificity and spatial and temporal resolution in order to understand their behavior. Bacterial metabolism involves a large number of internal and external electron transfer processes, so it is logical that electrochemical techniques have been employed to investigate these bacterial metabolites. In this mini-review, we focus on electrochemical and spectroelectrochemical methods that have been developed and used specifically to chemically characterize bacteria and their behavior. First, we discuss the latest mechanistic insights and current understanding of microbial electron transfer, including both direct and mediated electron transfer. Second, we summarize progress on approaches to spatiotemporal characterization of secreted factors, including both metabolites and signaling molecules, which can be used to discern how natural or external factors can alter metabolic states of bacterial cells and change either their individual or collective behavior. Finally, we address in situ methods of single-cell characterization, which can uncover how heterogeneity in cell behavior is reflected in the behavior and properties of collections of bacteria, e.g. bacterial communities. Recent advances in (spectro)electrochemical characterization of bacteria have yielded important new insights both at the ensemble and the single-entity levels, which are furthering our understanding of bacterial behavior. These insights, in turn, promise to benefit applications ranging from biosensors to the use of bacteria in bacteria-based bioenergy generation and storage.
Collapse
Affiliation(s)
- Vignesh Sundaresan
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN 46556, USA.
| | - Hyein Do
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Joshua D Shrout
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Paul W Bohn
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN 46556, USA.
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| |
Collapse
|
29
|
Valorisation of CO2 into Value-Added Products via Microbial Electrosynthesis (MES) and Electro-Fermentation Technology. FERMENTATION-BASEL 2021. [DOI: 10.3390/fermentation7040291] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Microbial electrocatalysis reckons on microbes as catalysts for reactions occurring at electrodes. Microbial fuel cells and microbial electrolysis cells are well-known in this context; both prefer the oxidation of organic and inorganic matter for producing electricity. Notably, the synthesis of high energy-density chemicals (fuels) or their precursors by microorganisms using bio-cathode to yield electrical energy is called Microbial Electrosynthesis (MES), giving an exceptionally appealing novel way for producing beneficial products from electricity and wastewater. This review accentuates the concept, importance and opportunities of MES, as an emerging discipline at the nexus of microbiology and electrochemistry. Production of organic compounds from MES is considered as an effective technique for the generation of various beneficial reduced end-products (like acetate and butyrate) as well as in reducing the load of CO2 from the atmosphere to mitigate the harmful effect of greenhouse gases in global warming. Although MES is still an emerging technology, this method is not thoroughly known. The authors have focused on MES, as it is the next transformative, viable alternative technology to decrease the repercussions of surplus carbon dioxide in the environment along with conserving energy.
Collapse
|
30
|
Bird LJ, Kundu BB, Tschirhart T, Corts AD, Su L, Gralnick JA, Ajo-Franklin CM, Glaven SM. Engineering Wired Life: Synthetic Biology for Electroactive Bacteria. ACS Synth Biol 2021; 10:2808-2823. [PMID: 34637280 DOI: 10.1021/acssynbio.1c00335] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Electroactive bacteria produce or consume electrical current by moving electrons to and from extracellular acceptors and donors. This specialized process, known as extracellular electron transfer, relies on pathways composed of redox active proteins and biomolecules and has enabled technologies ranging from harvesting energy on the sea floor, to chemical sensing, to carbon capture. Harnessing and controlling extracellular electron transfer pathways using bioengineering and synthetic biology promises to heighten the limits of established technologies and open doors to new possibilities. In this review, we provide an overview of recent advancements in genetic tools for manipulating native electroactive bacteria to control extracellular electron transfer. After reviewing electron transfer pathways in natively electroactive organisms, we examine lessons learned from the introduction of extracellular electron transfer pathways into Escherichia coli. We conclude by presenting challenges to future efforts and give examples of opportunities to bioengineer microbes for electrochemical applications.
Collapse
Affiliation(s)
- Lina J. Bird
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Biki B. Kundu
- PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, Texas 77005, United States
| | - Tanya Tschirhart
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Anna D. Corts
- Joyn Bio, Boston, Massachusetts 02210, United States
| | - Lin Su
- State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210018, People’s Republic of China
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Jeffrey A. Gralnick
- Department of Plant and Microbial Biology, BioTechnology Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
| | | | - Sarah M. Glaven
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, D.C. 20375, United States
| |
Collapse
|
31
|
Fang Z, Zhou J, Zhou X, Koffas MAG. Abiotic-biotic hybrid for CO 2 biomethanation: From electrochemical to photochemical process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 791:148288. [PMID: 34118677 DOI: 10.1016/j.scitotenv.2021.148288] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/01/2021] [Accepted: 06/01/2021] [Indexed: 06/12/2023]
Abstract
Converting CO2 into sustainable fuels (e.g., CH4) has great significance to solve carbon emission and energy crisis. Generally, CO2 methanation needs abundant of energy input to overcome the eight-electron-transfer barrier. Abiotic-biotic hybrid system represents one of the cutting-edge technologies that use renewable electric/solar energy to realize eight-electron-transfer CO2 biomethanation. However, the incompatible abiotic-biotic hybrid can result in low efficiency of electron transfer and CO2 biomethanation. Herein, we present the comprehensive review to highlight how to design abiotic-biotic hybrid for electric/solar-driven CO2 biomethanation. We primarily introduce the CO2 biomethanation mechanism, and further summarize state-of-the-art electrochemical and photochemical CO2 biomethanation in hybrid systems. We also propose excellent synthetic biology strategies, which are useful to design tunable methanogenic microorganisms or enzymes when cooperating with electrode/semiconductor in hybrid systems. This review provides theoretical guidance of abiotic-biotic hybrid and also shows the bright future of sustainable fuel production in the form of CO2 biomethanation.
Collapse
Affiliation(s)
- Zhen Fang
- Biofuels Institute, School of Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - Jun Zhou
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Xiangtong Zhou
- Institute of Environmental Health and Ecological Safety, Jiangsu University, Zhenjiang 212013, China
| | - Mattheos A G Koffas
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| |
Collapse
|
32
|
Rowe AR, Salimijazi F, Trutschel L, Sackett J, Adesina O, Anzai I, Kugelmass LH, Baym MH, Barstow B. Identification of a pathway for electron uptake in Shewanella oneidensis. Commun Biol 2021; 4:957. [PMID: 34381156 PMCID: PMC8357807 DOI: 10.1038/s42003-021-02454-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 07/14/2021] [Indexed: 02/06/2023] Open
Abstract
Extracellular electron transfer (EET) could enable electron uptake into microbial metabolism for the synthesis of complex, energy dense organic molecules from CO2 and renewable electricity1-6. Theoretically EET could do this with an efficiency comparable to H2-oxidation7,8 but without the need for a volatile intermediate and the problems it causes for scale up9. However, significant gaps remain in understanding the mechanism and genetics of electron uptake. For example, studies of electron uptake in electroactive microbes have shown a role for the Mtr EET complex in the electroactive microbe Shewanella oneidensis MR-110-14, though there is substantial variation in the magnitude of effect deletion of these genes has depending on the terminal electron acceptor used. This speaks to the potential for previously uncharacterized and/or differentially utilized genes involved in electron uptake. To address this, we screened gene disruption mutants for 3667 genes, representing ≈99% of all nonessential genes, from the S. oneidensis whole genome knockout collection using a redox dye oxidation assay. Confirmation of electron uptake using electrochemical testing allowed us to identify five genes from S. oneidensis that are indispensable for electron uptake from a cathode. Knockout of each gene eliminates extracellular electron uptake, yet in four of the five cases produces no significant defect in electron donation to an anode. This result highlights both distinct electron uptake components and an electronic connection between aerobic and anaerobic electron transport chains that allow electrons from the reversible EET machinery to be coupled to different respiratory processes in S. oneidensis. Homologs to these genes across many different genera suggesting that electron uptake by EET coupled to respiration could be widespread. These gene discoveries provide a foundation for: studying this phenotype in exotic metal-oxidizing microbes, genetic optimization of electron uptake in S. oneidensis; and genetically engineering electron uptake into a highly tractable host like E. coli to complement recent advances in synthetic CO2 fixation15.
Collapse
Affiliation(s)
- Annette R Rowe
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, USA.
| | - Farshid Salimijazi
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY, USA
| | - Leah Trutschel
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, USA
| | - Joshua Sackett
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, USA
| | | | - Isao Anzai
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | - Liat H Kugelmass
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | - Michael H Baym
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA
| | - Buz Barstow
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY, USA.
| |
Collapse
|
33
|
Xu B, Li Z, Jiang Y, Chen M, Chen B, Xin F, Dong W, Jiang M. Recent advances in the improvement of bi-directional electron transfer between abiotic/biotic interfaces in electron-assisted biosynthesis system. Biotechnol Adv 2021; 54:107810. [PMID: 34333092 DOI: 10.1016/j.biotechadv.2021.107810] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 07/06/2021] [Accepted: 07/26/2021] [Indexed: 12/18/2022]
Abstract
As an important biosynthesis technology, electron-assisted biosynthesis (EABS) system can utilize exogenous electrons to regulate the metabolic network of microorganisms, realizing the biosynthesis of high value-added chemicals and CO2 fixation. Electrons play crucial roles as the energy carriers in the EABS process. In fact, efficient interfacial electron transfer (ET) is the decisive factor to realize the rapid energy exchange, thus stimulating the biosynthesis of target metabolic products. However, due to the interfacial resistance of ET between the abiotic solid electrode and biotic microbial cells, the low efficiency of interfacial ET has become a major bottleneck, further limiting the practical application of EABS system. As the cell membrane is insulated, even the cell membrane embedded electron conduit (no matter cytochromes or channel protein for shuttle transferring) to increase the cell membrane conductivity, the ET between membrane electron conduit and electrode surface is kinetically restricted. In this review, the pathway of bi-directional interfacial ET in EABS system was summarized. Furthermore, we reviewed representative milestones and advances in both the anode outward interfacial ET (from organism to electrode) and cathode inward interfacial ET (from electrode to organism). Here, new insights from the perspectives of material science and synthetic biology were also proposed, which were expected to provide some innovative opinions and ideas for the following in-depth studies.
Collapse
Affiliation(s)
- Bin Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Zhe Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Minjiao Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Boryann Chen
- Department of Chemical and Materials Engineering, National I-Lan University, I-Lan 26047, Taiwan
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800, PR China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800, PR China.
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800, PR China.
| |
Collapse
|
34
|
Shewanella oneidensis MR-1 as a bacterial platform for electro-biotechnology. Essays Biochem 2021; 65:355-364. [PMID: 33769488 PMCID: PMC8314016 DOI: 10.1042/ebc20200178] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/16/2021] [Accepted: 03/18/2021] [Indexed: 12/18/2022]
Abstract
The genus Shewanella comprises over 70 species of heterotrophic bacteria with versatile respiratory capacities. Some of these bacteria are known to be pathogens of fishes and animals, while many are non-pathogens considered to play important roles in the global carbon cycle. A representative strain is Shewanella oneidensis MR-1 that has been intensively studied for its ability to respire diverse electron acceptors, such as oxygen, nitrate, sulfur compounds, metals, and organics. In addition, studies have been focused on its ability as an electrochemically active bacterium that is capable of discharging electrons to and receiving electrons from electrodes in bioelectrochemical systems (BESs) for balancing intracellular redox states. This ability is expected to be applied to electro-fermentation (EF) for producing value-added chemicals that conventional fermentation technologies are difficult to produce efficiently. Researchers are also attempting to utilize its electrochemical ability for controlling gene expression, for which electro-genetics (EG) has been coined. Here we review fundamental knowledge on this bacterium and discuss future directions of studies on its applications to electro-biotechnology (EB).
Collapse
|
35
|
Kouzuma A. Molecular mechanisms regulating the catabolic and electrochemical activities of Shewanella oneidensis MR-1. Biosci Biotechnol Biochem 2021; 85:1572-1581. [PMID: 33998649 DOI: 10.1093/bbb/zbab088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/17/2021] [Indexed: 11/14/2022]
Abstract
Electrochemically active bacteria (EAB) interact electrochemically with electrodes via extracellular electron transfer (EET) pathways. These bacteria have attracted significant attention due to their utility in environmental-friendly bioelectrochemical systems (BESs), including microbial fuel cells and electrofermentation systems. The electrochemical activity of EAB is dependent on their carbon catabolism and respiration; thus, understanding how these processes are regulated will provide insights into the development of a more efficient BES. The process of biofilm formation by EAB on BES electrodes is also important for electric current generation because it facilitates physical and electrochemical interactions between EAB cells and electrodes. This article summarizes the current knowledge on EET-related metabolic and cellular functions of a model EAB, Shewanella oneidensis MR-1, focusing specifically on regulatory systems for carbon catabolism, EET pathways, and biofilm formation. Based on recent developments, the author also discusses potential uses of engineered S. oneidensis strains for various biotechnological applications.
Collapse
Affiliation(s)
- Atsushi Kouzuma
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| |
Collapse
|
36
|
Kees ED, Levar CE, Miller SP, Bond DR, Gralnick JA, Dean AM. Survival of the first rather than the fittest in a Shewanella electrode biofilm. Commun Biol 2021; 4:536. [PMID: 33958697 PMCID: PMC8102560 DOI: 10.1038/s42003-021-02040-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 03/22/2021] [Indexed: 11/09/2022] Open
Abstract
For natural selection to operate there must exist heritable variation among individuals that affects their survival and reproduction. Among free-living microbes, where differences in growth rates largely define selection intensities, competitive exclusion is common. However, among surface attached communities, these dynamics become less predictable. If extreme circumstances were to dictate that a surface population is immortal and all offspring must emigrate, the offspring would be unable to contribute to the composition of the population. Meanwhile, the immortals, regardless of reproductive capacity, would remain unchanged in relative abundance. The normal cycle of birth, death, and competitive exclusion would be broken. We tested whether conditions required to set up this idealized scenario can be approximated in a microbial biofilm. Using two differentially-reproducing strains of Shewanella oneidensis grown on an anode as the sole terminal electron acceptor - a system in which metabolism is obligately tied to surface attachment - we found that selection against a slow-growing competitor is drastically reduced. This work furthers understanding of natural selection dynamics in sessile microbial communities, and provides a framework for designing stable microbial communities for industrial and experimental applications.
Collapse
Affiliation(s)
- Eric D Kees
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Caleb E Levar
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Stephen P Miller
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA
| | - Daniel R Bond
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Jeffrey A Gralnick
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA.
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA.
| | - Antony M Dean
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA.
- Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA.
| |
Collapse
|
37
|
Abstract
Transmembrane proteins involved in metabolic redox reactions and photosynthesis catalyse a plethora of key energy-conversion processes and are thus of great interest for bioelectrocatalysis-based applications. The development of membrane protein modified electrodes has made it possible to efficiently exchange electrons between proteins and electrodes, allowing mechanistic studies and potentially applications in biofuels generation and energy conversion. Here, we summarise the most common electrode modification and their characterisation techniques for membrane proteins involved in biofuels conversion and semi-artificial photosynthesis. We discuss the challenges of applications of membrane protein modified electrodes for bioelectrocatalysis and comment on emerging methods and future directions, including recent advances in membrane protein reconstitution strategies and the development of microbial electrosynthesis and whole-cell semi-artificial photosynthesis.
Collapse
|
38
|
Paquete CM. Electroactivity across the cell wall of Gram-positive bacteria. Comput Struct Biotechnol J 2020; 18:3796-3802. [PMID: 33335679 PMCID: PMC7720022 DOI: 10.1016/j.csbj.2020.11.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/11/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023] Open
Abstract
The growing interest on sustainable biotechnological processes for the production of energy and industrial relevant organic compounds have increased the discovery of electroactive organisms (i.e. organisms that are able to exchange electrons with an electrode) and the characterization of their extracellular electron transfer mechanisms. While most of the knowledge on extracellular electron transfer processes came from studies on Gram-negative bacteria, less is known about the processes performed by Gram-positive bacteria. In contrast to Gram-negative bacteria, Gram-positive bacteria lack an outer-membrane and contain a thick cell wall, which were thought to prevent extracellular electron transfer. However, in the last decade, an increased number of Gram-positive bacteria have been found to perform extracellular electron transfer, and exchange electrons with an electrode. In this mini-review the current knowledge on the extracellular electron transfer processes performed by Gram-positive bacteria is introduced, emphasising their electroactive role in bioelectrochemical systems. Also, the existent information of the molecular processes by which these bacteria exchange electrons with an electrode is highlighted. This understanding is fundamental to advance the implementation of these organisms in sustainable biotechnological processes, either through modification of the systems or through genetic engineering, where the organisms can be optimized to become better catalysts.
Collapse
Affiliation(s)
- Catarina M. Paquete
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Portugal
| |
Collapse
|
39
|
Chen H, Simoska O, Lim K, Grattieri M, Yuan M, Dong F, Lee YS, Beaver K, Weliwatte S, Gaffney EM, Minteer SD. Fundamentals, Applications, and Future Directions of Bioelectrocatalysis. Chem Rev 2020; 120:12903-12993. [DOI: 10.1021/acs.chemrev.0c00472] [Citation(s) in RCA: 118] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Hui Chen
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Olja Simoska
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Koun Lim
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Matteo Grattieri
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Mengwei Yuan
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Fangyuan Dong
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Yoo Seok Lee
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Kevin Beaver
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Samali Weliwatte
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Erin M. Gaffney
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| | - Shelley D. Minteer
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt Lake City, Utah 84112, United States
| |
Collapse
|
40
|
Yates MD, Bird LJ, Eddie BJ, Onderko EL, Voigt CA, Glaven SM. Nanoliter scale electrochemistry of natural and engineered electroactive bacteria. Bioelectrochemistry 2020; 137:107644. [PMID: 32971484 DOI: 10.1016/j.bioelechem.2020.107644] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/21/2020] [Accepted: 08/26/2020] [Indexed: 01/09/2023]
Abstract
Bacterial extracellular electron transfer (EET) is envisioned for use in applied biotechnologies, necessitating electrochemical characterization of natural and engineered electroactive biofilms under conditions similar to the target application, including small-scale biosensing or biosynthesis platforms, which is often distinct from standard 100 mL-scale stirred-batch bioelectrochemical test platforms used in the laboratory. Here, we adapted an eight chamber, nanoliter volume (500 nL) electrochemical flow cell to grow biofilms of both natural (Biocathode MCL community, Marinobacter atlanticus, and Shewanella oneidensis MR1) or genetically modified (S. oneidensis ΔMtr and S. oneidensis ΔMtr + pLB2) electroactive bacteria on electrodes held at a constant potential. Maximum current density achieved by unmodified strains was similar between the nano- and milliliter-scale reactors. However, S. oneidensis biofilms engineered to activate EET upon exposure to 2,4-diacetylphloroglucinol (DAPG) produced current at wild-type levels in the stirred-batch reactor, but not in the nanoliter flow cell. We hypothesize this was due to differences in mass transport of DAPG, naturally-produced soluble redox mediators, and oxygen between the two reactor types. Results presented here demonstrate, for the first time, nanoliter scale chronoamperometry and cyclic voltammetry of a range of electroactive bacteria in a three-electrode reactor system towards development of miniaturized, and potentially high throughput, bioelectrochemical platforms.
Collapse
Affiliation(s)
- Matthew D Yates
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, USA.
| | - Lina J Bird
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, USA
| | - Brian J Eddie
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, USA
| | | | - Christopher A Voigt
- Department of Biological Engineering and the Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sarah M Glaven
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, USA.
| |
Collapse
|
41
|
Gong Z, Yu H, Zhang J, Li F, Song H. Microbial electro-fermentation for synthesis of chemicals and biofuels driven by bi-directional extracellular electron transfer. Synth Syst Biotechnol 2020; 5:304-313. [PMID: 32995586 PMCID: PMC7490822 DOI: 10.1016/j.synbio.2020.08.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/23/2020] [Accepted: 08/25/2020] [Indexed: 11/16/2022] Open
Abstract
Electroactive bacteria could perform bi-directional extracellular electron transfer (EET) to exchange electrons and energy with extracellular environments, thus playing a central role in microbial electro-fermentation (EF) process. Unbalanced fermentation and microbial electrosynthesis are the main pathways to produce value-added chemicals and biofuels. However, the low efficiency of the bi-directional EET is a dominating bottleneck in these processes. In this review, we firstly demonstrate the main bi-directional EET mechanisms during EF, including the direct EET and the shuttle-mediated EET. Then, we review representative milestones and progresses in unbalanced fermentation via anode outward EET and microbial electrosynthesis via inward EET based on these two EET mechanisms in detail. Furthermore, we summarize the main synthetic biology strategies in improving the bi-directional EET and target products synthesis, thus to enhance the efficiencies in unbalanced fermentation and microbial electrosynthesis. Lastly, a perspective on the applications of microbial electro-fermentation is provided.
Collapse
Affiliation(s)
- Ziying Gong
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Huan Yu
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Junqi Zhang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Feng Li
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Hao Song
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| |
Collapse
|
42
|
Wroblewska-Wolna AM, Harvie AJ, Rowe SF, Critchley K, Butt JN, Jeuken LJC. Quantum dot interactions with and toxicity to Shewanella oneidensis MR-1. NANOTECHNOLOGY 2020; 31:134005. [PMID: 31810073 DOI: 10.1088/1361-6528/ab5f78] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Combining abiotic photosensitisers such as quantum dots (QDs) with non-photosynthetic bacteria presents an intriguing concept into the design of artificial photosynthetic organisms and solar-driven fuel production. Shewanella oneidensis MR-1 (MR-1) is a versatile bacterium concerning respiration, metabolism and biocatalysis, and is a promising organism for artificial photosynthesis as the bacterium's synthetic and catalytic ability provides a potential system for bacterial biohydrogen production. MR-1's hydrogenases are present in the periplasmatic space. It follows that for photoenergised electrons to reach these enzymes, QDs will need to be able to enter the periplasm, or electrons need to enter the periplasm via the Mtr pathway that is responsible for MR-1's extracellular electron transfer ability. As a step towards this goal, various QDs were tested for their photo-reducing potential, nanotoxicology and further for their interaction with MR-1. CdTe/CdS/TGA, CdTe/CdS/Cysteamine, a commercial, negatively charged CdTe and CuInS2/ZnS/PMAL QDs were examined. The photoreduction potential of the QDs was confirmed by measuring their ability to photoreduce methyl viologen with different sacrificial electron donors. The commercial CdTe and CuInS2/ZnS/PMAL QDs showed no toxicity towards MR-1 as evaluated by a colony-forming units method and a fluorescence viability assay. Only the commercial negatively charged CdTe QDs showed good interaction with MR-1. With transmission electron microscopy, QDs were observed both in the cytoplasm and periplasm. These results inform on the possibilities and bottlenecks when developing bionanotechnological systems for the photosynthetic production of biohydrogen by MR-1.
Collapse
|
43
|
Strategies for improving the electroactivity and specific metabolic functionality of microorganisms for various microbial electrochemical technologies. Biotechnol Adv 2019; 39:107468. [PMID: 31707076 DOI: 10.1016/j.biotechadv.2019.107468] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 11/02/2019] [Accepted: 11/04/2019] [Indexed: 01/31/2023]
Abstract
Electroactive microorganisms, which possess extracellular electron transfer (EET) capabilities, are the basis of microbial electrochemical technologies (METs) such as microbial fuel and electrolysis cells. These are considered for several applications ranging from the energy-efficient treatment of waste streams to the production of value-added chemicals and fuels, bioremediation, and biosensing. Various aspects related to the microorganisms, electrodes, separators, reactor design, and operational or process parameters influence the overall functioning of METs. The most fundamental and critical performance-determining factor is, however, the microorganism-electrode interactions. Modification of the electrode surfaces and microorganisms for optimizing their interactions has therefore been the major MET research focus area over the last decade. In the case of microorganisms, primarily their EET mechanisms and efficiencies along with the biofilm formation capabilities, collectively considered as microbial electroactivity, affect their interactions with the electrodes. In addition to electroactivity, the specific metabolic or biochemical functionality of microorganisms is equally crucial to the target MET application. In this article, we present the major strategies that are used to enhance the electroactivity and specific functionality of microorganisms pertaining to both anodic and cathodic processes of METs. These include simple physical methods based on the use of heat and magnetic field along with chemical, electrochemical, and growth media amendment approaches to the complex procedure-based microbial bioaugmentation, co-culture, and cell immobilization or entrapment, and advanced toolkit-based biofilm engineering, genetic modifications, and synthetic biology strategies. We further discuss the applicability and limitations of these strategies and possible future research directions for advancing the highly promising microbial electrochemistry-driven biotechnology.
Collapse
|
44
|
Gupta D, Sutherland MC, Rengasamy K, Meacham JM, Kranz RG, Bose A. Photoferrotrophs Produce a PioAB Electron Conduit for Extracellular Electron Uptake. mBio 2019; 10:e02668-19. [PMID: 31690680 PMCID: PMC6831781 DOI: 10.1128/mbio.02668-19] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 11/20/2022] Open
Abstract
Photoferrotrophy is a form of anoxygenic photosynthesis whereby bacteria utilize soluble or insoluble forms of ferrous iron as an electron donor to fix carbon dioxide using light energy. They can also use poised electrodes as their electron donor via phototrophic extracellular electron uptake (phototrophic EEU). The electron uptake mechanisms underlying these processes are not well understood. Using Rhodopseudomonas palustris TIE-1 as a model, we show that a single periplasmic decaheme cytochrome c, PioA, and an outer membrane porin, PioB, form a complex allowing extracellular electron uptake across the outer membrane from both soluble iron and poised electrodes. We observe that PioA undergoes postsecretory proteolysis of its N terminus to produce a shorter heme-attached PioA (holo-PioAC, where PioAC represents the C terminus of PioA), which can exist both freely in the periplasm and in a complex with PioB. The extended N-terminal peptide controls heme attachment, and its processing is required to produce wild-type levels of holo-PioAC and holo-PioACB complex. It is also conserved in PioA homologs from other phototrophs. The presence of PioAB in these organisms correlate with their ability to perform photoferrotrophy and phototrophic EEU.IMPORTANCE Some anoxygenic phototrophs use soluble iron, insoluble iron minerals (such as rust), or their proxies (poised electrodes) as electron donors for photosynthesis. However, the underlying electron uptake mechanisms are not well established. Here, we show that these phototrophs use a protein complex made of an outer membrane porin and a periplasmic decaheme cytochrome (electron transfer protein) to harvest electrons from both soluble iron and poised electrodes. This complex has two unique characteristics: (i) it lacks an extracellular cytochrome c, and (ii) the periplasmic decaheme cytochrome c undergoes proteolytic cleavage to produce a functional electron transfer protein. These characteristics are conserved in phototrophs harboring homologous proteins.
Collapse
Affiliation(s)
- Dinesh Gupta
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Molly C Sutherland
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | | | - J Mark Meacham
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, Missouri, USA
- Institute of Materials Science and Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Robert G Kranz
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Arpita Bose
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| |
Collapse
|
45
|
Glaven SM. Bioelectrochemical systems and synthetic biology: more power, more products. Microb Biotechnol 2019; 12:819-823. [PMID: 31264368 PMCID: PMC6680619 DOI: 10.1111/1751-7915.13456] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Sarah M Glaven
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, USA
| |
Collapse
|