1
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Qi X, Liu X, Gu Y, Liang P. Whole-cell biophotovoltaic systems for renewable energy generation: A systematic analysis of existing knowledge. Bioelectrochemistry 2024; 158:108695. [PMID: 38531227 DOI: 10.1016/j.bioelechem.2024.108695] [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: 01/04/2024] [Revised: 03/20/2024] [Accepted: 03/22/2024] [Indexed: 03/28/2024]
Abstract
The development of carbon-neutral fuel sources is an essential step in addressing the global fossil energy crisis. Whole-cell biophotovoltaic systems (BPVs) are a renewable, non-polluting energy-generating device that utilizes oxygenic photosynthetic microbes (OPMs) to split water molecules and generate bioelectricity under the driving of light energy. Since 2006, BPVs have been widely studied, with the order magnitudes of power density increasing from 10-4 mW/m2 to 103 mW/m2. This review examines the extracellular electron transfer (EET) mechanisms and regulation techniques of BPVs from biofilm to external environment. It is found that the EET of OPMs is mainly mediated by membrane proteins, with terminal oxidase limiting the power output. Synechocystis sp. PCC6803 and Chlorella vulgaris are two species that produce high power density in BPVs. The use of metal nanoparticles mixing, 3D pillar array electrodes, microfluidic technology, and transient-state operation models can significantly enhance power density. Challenges and potential research directions are discussed, including a deeper analysis of EET mechanisms and dynamics, the development of modular devices, integration of multiple regulatory components, and the exploration of novel BPV technologies.
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Affiliation(s)
- Xiang Qi
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xinning Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yuyi Gu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Peng Liang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
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2
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Zhu H, Cabrerizo FM, Li J, He T, Li Y. Rewiring Photosynthesis by Water-Soluble Fullerene Derivatives for Solar-Powered Electricity Generation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2310245. [PMID: 38647389 PMCID: PMC11187915 DOI: 10.1002/advs.202310245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 03/31/2024] [Indexed: 04/25/2024]
Abstract
Natural photosynthesis holds great potential to generate clean electricity from solar energy. In order to utilize this process for power generation, it is necessary to rewire photosynthetic electron transport chains (PETCs) of living photosynthetic organisms to redirect more electron flux toward an extracellular electrode. In this study, a semi-artificial rewiring strategy, which use a water-soluble fullerene derivative to capture electrons from PETCs and donate them for electrical current generation, is proposed. A positively charged fullerene derivative, functionalized with N,N-dimethyl pyrrolidinium iodide, is found to be efficiently taken up by the cyanobacterium Synechocystis sp. PCC 6803. The distribution of this fullerene derivative near the thylakoid membrane, as well as site-specific inhibitor assays and transient absorption spectroscopy, suggest that it can directly interact with the redox centers in the PETCs, particularly the acceptor side of photosystem I (PSI). The internalized fullerene derivatives facilitate the extraction of photosynthetic electrons and significantly enhance the photocurrent density of Synechocystis by approximately tenfold. This work opens up new possibility for the application of fullerenes as an excellent 3D electron carrier in living biophotovoltaics.
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Affiliation(s)
- Huawei Zhu
- CAS Key Laboratory of Microbial Physiological and Metabolic EngineeringState Key Laboratory of Microbial ResourcesInstitute of MicrobiologyChinese Academy of SciencesBeijing100101China
| | - Franco M. Cabrerizo
- Instituto Tecnológico de Chascomús (CONICET‐UNSAM)Av. Intendente Marino Km 8.2, CC 164 (B7130IWA)ChascomúsCP7130Argentina
| | - Jing Li
- Key Laboratory of Photochemical Conversion and Optoelectronic MaterialsTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing100190China
| | - Tao He
- CAS Key Laboratory of Nanosystem and Hierarchical FabricationNational Center for Nanoscience and TechnologyBeijing100190China
| | - Yin Li
- CAS Key Laboratory of Microbial Physiological and Metabolic EngineeringState Key Laboratory of Microbial ResourcesInstitute of MicrobiologyChinese Academy of SciencesBeijing100101China
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3
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Koehle AP, Brumwell SL, Seto EP, Lynch AM, Urbaniak C. Microbial applications for sustainable space exploration beyond low Earth orbit. NPJ Microgravity 2023; 9:47. [PMID: 37344487 DOI: 10.1038/s41526-023-00285-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 05/25/2023] [Indexed: 06/23/2023] Open
Abstract
With the construction of the International Space Station, humans have been continuously living and working in space for 22 years. Microbial studies in space and other extreme environments on Earth have shown the ability for bacteria and fungi to adapt and change compared to "normal" conditions. Some of these changes, like biofilm formation, can impact astronaut health and spacecraft integrity in a negative way, while others, such as a propensity for plastic degradation, can promote self-sufficiency and sustainability in space. With the next era of space exploration upon us, which will see crewed missions to the Moon and Mars in the next 10 years, incorporating microbiology research into planning, decision-making, and mission design will be paramount to ensuring success of these long-duration missions. These can include astronaut microbiome studies to protect against infections, immune system dysfunction and bone deterioration, or biological in situ resource utilization (bISRU) studies that incorporate microbes to act as radiation shields, create electricity and establish robust plant habitats for fresh food and recycling of waste. In this review, information will be presented on the beneficial use of microbes in bioregenerative life support systems, their applicability to bISRU, and their capability to be genetically engineered for biotechnological space applications. In addition, we discuss the negative effect microbes and microbial communities may have on long-duration space travel and provide mitigation strategies to reduce their impact. Utilizing the benefits of microbes, while understanding their limitations, will help us explore deeper into space and develop sustainable human habitats on the Moon, Mars and beyond.
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Affiliation(s)
- Allison P Koehle
- Department of Plant Science, Pennsylvania State University, University Park, PA, USA
| | - Stephanie L Brumwell
- Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, Canada
| | | | - Anne M Lynch
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Graduate Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
| | - Camilla Urbaniak
- ZIN Technologies Inc, Middleburg Heights, OH, USA.
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
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4
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Zhu H, Wang H, Zhang Y, Li Y. Biophotovoltaics: Recent advances and perspectives. Biotechnol Adv 2023; 64:108101. [PMID: 36681132 DOI: 10.1016/j.biotechadv.2023.108101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 01/02/2023] [Accepted: 01/15/2023] [Indexed: 01/19/2023]
Abstract
Biophotovoltaics (BPV) is a clean power generation technology that uses self-renewing photosynthetic microorganisms to capture solar energy and generate electrical current. Although the internal quantum efficiency of charge separation in photosynthetic microorganisms is very high, the inefficient electron transfer from photosystems to the extracellular electrodes hampered the electrical outputs of BPV systems. This review summarizes the approaches that have been taken to increase the electrical outputs of BPV systems in recent years. These mainly include redirecting intracellular electron transfer, broadening available photosynthetic microorganisms, reinforcing interfacial electron transfer and design high-performance devices with different configurations. Furthermore, three strategies developed to extract photosynthetic electrons were discussed. Among them, the strategy of using synthetic microbial consortia could circumvent the weak exoelectrogenic activity of photosynthetic microorganisms and the cytotoxicity of exogenous electron mediators, thus show great potential in enhancing the power output and prolonging the lifetime of BPV systems. Lastly, we prospected how to facilitate electron extraction and further improve the performance of BPV systems.
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Affiliation(s)
- Huawei Zhu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Haowei Wang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanping Zhang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yin Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
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5
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Schneider H, Lai B, Krömer J. Utilizing Cyanobacteria in Biophotovoltaics: An Emerging Field in Bioelectrochemistry. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2023; 183:281-302. [PMID: 36441187 DOI: 10.1007/10_2022_212] [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: 11/29/2022]
Abstract
Anthropogenic global warming is driven by the increasing energy demand and the still dominant use of fossil energy carriers to meet these needs. New carbon-neutral energy sources are urgently needed to solve this problem. Biophotovoltaics, a member of the so-called bioelectrochemical systems family, will provide an important piece of the energy puzzle. It aims to harvest the electrons from sunlight-driven water splitting using the natural oxygenic photosystem (e.g., of cyanobacteria) and utilize them in the form of, e.g., electricity or hydrogen. Several key aspects of biophotovoltaics have been intensively studied in recent years like physicochemical properties of electrodes or efficient wiring of microorganisms to electrodes. Yet, the exact mechanisms of electron transfer between the biocatalyst and the electrode remain unresolved today. Most research is conducted on microscale reactors generating small currents over short time-scales, but multiple experiments have shown biophotovoltaics great potential with lab-scale reactors producing currents over weeks to months. Although biophotovoltaics is still in its infancy with many open research questions to be addressed, new promising results from various labs around the world suggest an important opportunity for biophotovoltaics in the decades to come. In this chapter, we will introduce the concept of biophotovoltaics, summarize its recent key progress, and finally critically discuss the potentials and challenges for future rational development of biophotovoltaics.
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Affiliation(s)
- Hans Schneider
- Department of Solar Materials, Helmholtz Center for Environmental Research, Leipzig, Germany.
| | - Bin Lai
- Department of Solar Materials, Helmholtz Center for Environmental Research, Leipzig, Germany
| | - Jens Krömer
- Department of Solar Materials, Helmholtz Center for Environmental Research, Leipzig, Germany
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6
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Hatano J, Kusama S, Tanaka K, Kohara A, Miyake C, Nakanishi S, Shimakawa G. NADPH production in dark stages is critical for cyanobacterial photocurrent generation: a study using mutants deficient in oxidative pentose phosphate pathway. PHOTOSYNTHESIS RESEARCH 2022; 153:113-120. [PMID: 35182311 DOI: 10.1007/s11120-022-00903-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 01/16/2022] [Indexed: 06/14/2023]
Abstract
Live cyanobacteria and algae integrated onto an extracellular electrode can generate a light-induced current (i.e., a photocurrent). Although the photocurrent is expected to be correlated with the redox environment of the photosynthetic cells, the relationship between the photocurrent and the cellular redox state is poorly understood. Here, we investigated the effect of the reduced nicotinamide adenine dinucleotide phosphate [NADP(H)] redox level of cyanobacterial cells (before light exposure) on the photocurrent using several mutants (Δzwf, Δgnd, and ΔglgP) deficient in the oxidative pentose phosphate (OPP) pathway, which is the metabolic pathway that produces NADPH in darkness. The NAD(P)H redox level and photocurrent in the cyanobacterium Synechocystis sp. PCC 6803 were measured noninvasively. Dysfunction of the OPP pathway led to oxidation of the photosynthetic NADPH pool in darkness. In addition, photocurrent induction was retarded and the current density was lower in Δzwf, Δgnd, and ΔglgP than in wild-type cells. Exogenously added glucose compensated the phenotype of ΔglgP and drove the OPP pathway in the mutant, resulting in an increase in the photocurrent. The results indicated that NADPH accumulated by the OPP pathway before illumination is a key factor for the generation of a photocurrent. In addition, measuring the photocurrent can be a non-invasive approach to estimate the cellular redox level related to NADP(H) pool in cyanobacteria.
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Affiliation(s)
- Jiro Hatano
- Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8631, Japan
| | - Shoko Kusama
- Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8631, Japan
| | - Kenya Tanaka
- Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8631, Japan
- Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Ayaka Kohara
- Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501, Japan
| | - Chikahiro Miyake
- Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501, Japan
| | - Shuji Nakanishi
- Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8631, Japan.
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Osaka, 565-0871, Japan.
| | - Ginga Shimakawa
- Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8631, Japan.
- Department of Bioscience, School of Biological and Environmental Sciences, Kwansei-Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan.
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7
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Chen X, Lawrence JM, Wey LT, Schertel L, Jing Q, Vignolini S, Howe CJ, Kar-Narayan S, Zhang JZ. 3D-printed hierarchical pillar array electrodes for high-performance semi-artificial photosynthesis. NATURE MATERIALS 2022; 21:811-818. [PMID: 35256790 DOI: 10.1038/s41563-022-01205-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 01/18/2022] [Indexed: 06/14/2023]
Abstract
The rewiring of photosynthetic biomachineries to electrodes is a forward-looking semi-artificial route for sustainable bio-electricity and fuel generation. Currently, it is unclear how the electrode and biomaterial interface can be designed to meet the complex requirements for high biophotoelectrochemical performance. Here we developed an aerosol jet printing method for generating hierarchical electrode structures using indium tin oxide nanoparticles. We printed libraries of micropillar array electrodes varying in height and submicrometre surface features, and studied the energy/electron transfer processes across the bio-electrode interfaces. When wired to the cyanobacterium Synechocystis sp. PCC 6803, micropillar array electrodes with microbranches exhibited favourable biocatalyst loading, light utilization and electron flux output, ultimately almost doubling the photocurrent of state-of-the-art porous structures of the same height. When the micropillars' heights were increased to 600 µm, milestone mediated photocurrent densities of 245 µA cm-2 (the closest thus far to theoretical predictions) and external quantum efficiencies of up to 29% could be reached. This study demonstrates how bio-energy from photosynthesis could be more efficiently harnessed in the future and provide new tools for three-dimensional electrode design.
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Affiliation(s)
- Xiaolong Chen
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | | | - Laura T Wey
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Lukas Schertel
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Qingshen Jing
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Silvia Vignolini
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | | | - Sohini Kar-Narayan
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Jenny Z Zhang
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK.
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8
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Decomposing biophotovoltaic current density profiles using the Hilbert-Huang transform reveals influences of circadian clock on cyanobacteria exoelectrogenesis. Sci Rep 2022; 12:10962. [PMID: 35768500 PMCID: PMC9243294 DOI: 10.1038/s41598-022-15111-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 04/14/2022] [Indexed: 11/21/2022] Open
Abstract
Electrons from cyanobacteria photosynthetic and respiratory systems are implicated in current generated in biophotovoltaic (BPV) devices. However, the pathway that electrons follow to electrodes remains largely unknown, limiting progress of applied research. Here we use Hilbert–Huang Transforms to decompose Synechococcus elongatus sp. PCC7942 BPV current density profiles into physically meaningful oscillatory components, and compute their instantaneous frequencies. We develop hypotheses for the genesis of the oscillations via repeat experiments with iron-depleted and 20% CO\documentclass[12pt]{minimal}
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\begin{document}$${_2}$$\end{document}2 enriched biofilms. The oscillations exhibit rhythms that are consistent with the state of the art cyanobacteria circadian model, and putative exoelectrogenic pathways. In particular, we observe oscillations consistent with: rhythmic D1:1 (photosystem II core) expression; circadian-controlled glycogen accumulation; circadian phase shifts under modified intracellular %ATP; and circadian period shortening in the absence of the iron-sulphur protein LdpA. We suggest that the extracted oscillations may be used to reverse-identify proteins and/or metabolites responsible for cyanobacteria exoelectrogenesis.
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9
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Order-of-magnitude enhancement in photocurrent generation of Synechocystis sp. PCC 6803 by outer membrane deprivation. Nat Commun 2022; 13:3067. [PMID: 35654796 PMCID: PMC9163127 DOI: 10.1038/s41467-022-30764-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 05/17/2022] [Indexed: 12/24/2022] Open
Abstract
Biophotovoltaics (BPV) generates electricity from reducing equivalent(s) produced by photosynthetic organisms by exploiting a phenomenon called extracellular electron transfer (EET), where reducing equivalent(s) is transferred to external electron acceptors. Although cyanobacteria have been extensively studied for BPV because of their high photosynthetic activity and ease of handling, their low EET activity poses a limitation. Here, we show an order-of-magnitude enhancement in photocurrent generation of the cyanobacterium Synechocystis sp. PCC 6803 by deprivation of the outer membrane, where electrons are suggested to stem from pathway(s) downstream of photosystem I. A marked enhancement of EET activity itself is verified by rapid reduction of exogenous electron acceptor, ferricyanide. The extracellular organic substances, including reducing equivalent(s), produced by this cyanobacterium serve as respiratory substrates for other heterotrophic bacteria. These findings demonstrate that the outer membrane is a barrier that limits EET. Therefore, depriving this membrane is an effective approach to exploit the cyanobacterial reducing equivalent(s). The low extracellular electron transfer activity hampers the application of cyanobacteria in biophotovoltaics. Here, the authors report an order-of-magnitude enhancement in photocurrent generation of the cyanobacterium by deprivation of the outer cell membrane.
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10
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Buscemi G, Vona D, Stufano P, Labarile R, Cosma P, Agostiano A, Trotta M, Farinola GM, Grattieri M. Bio-Inspired Redox-Adhesive Polydopamine Matrix for Intact Bacteria Biohybrid Photoanodes. ACS APPLIED MATERIALS & INTERFACES 2022; 14:26631-26641. [PMID: 35639658 PMCID: PMC9204692 DOI: 10.1021/acsami.2c02410] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/20/2022] [Indexed: 05/24/2023]
Abstract
Interfacing intact and metabolically active photosynthetic bacteria with abiotic electrodes requires both establishing extracellular electron transfer and immobilizing the biocatalyst on electrode surfaces. Artificial approaches for photoinduced electron harvesting through redox polymers reported in literature require the separate synthesis of artificial polymeric matrices and their subsequent combination with bacterial cells, making the development of biophotoanodes complex and less sustainable. Herein, we report a one-pot biocompatible and sustainable approach, inspired by the byssus of mussels, that provides bacterial cells adhesion on multiple surfaces under wet conditions to obtain biohybrid photoanodes with facilitated photoinduced electron harvesting. Purple bacteria were utilized as a model organism, as they are of great interest for the development of photobioelectrochemical systems for H2 and NH3 synthesis, biosensing, and bioremediation purposes. The polydopamine matrix preparation strategy allowed the entrapment of active purple bacteria cells by initial oxygenic polymerization followed by electrochemical polymerization. Our results unveil that the deposition of bacterial cells with simultaneous polymerization of polydopamine on the electrode surface enables a 5-fold enhancement in extracellular electron transfer at the biotic/abiotic interface while maintaining the viability of the cells. The presented approach paves the way for a more sustainable development of biohybrid photoelectrodes.
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Affiliation(s)
- Gabriella Buscemi
- Dipartimento
di Chimica, Università degli Studi
di Bari “Aldo Moro”, via E. Orabona 4, Bari 70125, Italy
- IPCF-CNR
Istituto per i Processi Chimico Fisici, Consiglio Nazionale delle Ricerche, via E. Orabona 4, Bari 70125, Italy
| | - Danilo Vona
- Dipartimento
di Chimica, Università degli Studi
di Bari “Aldo Moro”, via E. Orabona 4, Bari 70125, Italy
| | - Paolo Stufano
- CNR-NANOTEC,
Institute of Nanotechnology, Consiglio Nazionale
delle Ricerche, via E. Orabona 4, Bari 70125, Italy
| | - Rossella Labarile
- Dipartimento
di Chimica, Università degli Studi
di Bari “Aldo Moro”, via E. Orabona 4, Bari 70125, Italy
- IPCF-CNR
Istituto per i Processi Chimico Fisici, Consiglio Nazionale delle Ricerche, via E. Orabona 4, Bari 70125, Italy
| | - Pinalysa Cosma
- Dipartimento
di Chimica, Università degli Studi
di Bari “Aldo Moro”, via E. Orabona 4, Bari 70125, Italy
- IPCF-CNR
Istituto per i Processi Chimico Fisici, Consiglio Nazionale delle Ricerche, via E. Orabona 4, Bari 70125, Italy
| | - Angela Agostiano
- Dipartimento
di Chimica, Università degli Studi
di Bari “Aldo Moro”, via E. Orabona 4, Bari 70125, Italy
- IPCF-CNR
Istituto per i Processi Chimico Fisici, Consiglio Nazionale delle Ricerche, via E. Orabona 4, Bari 70125, Italy
| | - Massimo Trotta
- IPCF-CNR
Istituto per i Processi Chimico Fisici, Consiglio Nazionale delle Ricerche, via E. Orabona 4, Bari 70125, Italy
| | - Gianluca M. Farinola
- Dipartimento
di Chimica, Università degli Studi
di Bari “Aldo Moro”, via E. Orabona 4, Bari 70125, Italy
| | - Matteo Grattieri
- Dipartimento
di Chimica, Università degli Studi
di Bari “Aldo Moro”, via E. Orabona 4, Bari 70125, Italy
- IPCF-CNR
Istituto per i Processi Chimico Fisici, Consiglio Nazionale delle Ricerche, via E. Orabona 4, Bari 70125, Italy
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11
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A biophotoelectrochemical approach to unravelling the role of cyanobacterial cell structures in exoelectrogenesis. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.139214] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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12
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Firoozabadi H, Mardanpour MM, Motamedian E. A system-oriented strategy to enhance electron production of Synechocystis sp. PCC6803 in bio-photovoltaic devices: experimental and modeling insights. Sci Rep 2021; 11:12294. [PMID: 34112928 PMCID: PMC8192556 DOI: 10.1038/s41598-021-91906-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 06/02/2021] [Indexed: 02/05/2023] Open
Abstract
Bio-photovoltaic devices (BPVs) harness photosynthetic organisms to produce bioelectricity in an eco-friendly way. However, their low energy efficiency is still a challenge. A comprehension of metabolic constraints can result in finding strategies for efficiency enhancement. This study presents a systemic approach based on metabolic modeling to design a regulatory defined medium, reducing the intracellular constraints in bioelectricity generation of Synechocystis sp. PCC6803 through the cellular metabolism alteration. The approach identified key reactions that played a critical role in improving electricity generation in Synechocystis sp. PCC6803 by comparing multiple optimal solutions of minimal and maximal NADH generation using two criteria. Regulatory compounds, which controlled the enzyme activity of the key reactions, were obtained from the BRENDA database. The selected compounds were subsequently added to the culture media, and their effect on bioelectricity generation was experimentally assessed. The power density curves for different culture media showed the BPV fed by Synechocystis sp. PCC6803 suspension in BG-11 supplemented with NH4Cl achieved the maximum power density of 148.27 mW m-2. This produced power density was more than 40.5-fold of what was obtained for the BPV fed with cyanobacterial suspension in BG-11. The effect of the activators on BPV performance was also evaluated by comparing their overpotential, maximum produced power density, and biofilm morphology under different conditions. These findings demonstrated the crucial role of cellular metabolism in improving bioelectricity generation in BPVs.
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Affiliation(s)
- Hossein Firoozabadi
- grid.412266.50000 0001 1781 3962Department of Biotechnology, Faculty of Chemical Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran, Iran
| | - Mohammad Mahdi Mardanpour
- grid.412553.40000 0001 0740 9747Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
| | - Ehsan Motamedian
- grid.412266.50000 0001 1781 3962Department of Biotechnology, Faculty of Chemical Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran, Iran
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13
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Lai B, Schneider H, Tschörtner J, Schmid A, Krömer JO. Technical-scale biophotovoltaics for long-term photo-current generation from Synechocystis sp. PCC6803. Biotechnol Bioeng 2021; 118:2637-2648. [PMID: 33844269 DOI: 10.1002/bit.27784] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/26/2021] [Accepted: 04/05/2021] [Indexed: 11/09/2022]
Abstract
A carbon-free energy supply is essential to sustain our future. Biophotovoltaics (BPV) provides a promising solution for hydrogen supply by directly coupling light-driven water splitting to hydrogen formation using oxygenic photoautotrophic cyanobacteria. However, BPV is currently limited by its low photon-to-current efficiency, and current experimental setups at a miniaturized scale hinder the rational investigation of the process and thus system optimization. In this article, we developed and optimized a new technical-scale (~250 ml working volume) BPV platform with defined and controllable operating parameters. Factors that interfered with reproducible and stable current output signals were identified and adapted. We found that the classical BG11 medium, used for the cultivation of cyanobacteria and also in many BPV studies, caused severe interferences in the bioelectrochemical experiments. An optimized nBG11 medium guaranteed a low and stable background current in the BPV reactor, regardless of the presence of light and/or mediators. As proof-of-principle, a very high long-term light-dependent current output (peak current of over 20 µA) was demonstrated in the new set-up over 12 days with living Synechocystis sp. PCC6803 cells and validated with appropriate controls. These results report the first reliable BPV platform generating reproducible photocurrent while still allowing quantitative investigation, rational optimization, and scale-up of BPV processes.
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Affiliation(s)
- Bin Lai
- Systems Biotechnology group, Department of Solar Materials, Helmholtz Centre for Environmental Research - UFZ, Leipzig, 04318, Germany
| | - Hans Schneider
- Systems Biotechnology group, Department of Solar Materials, Helmholtz Centre for Environmental Research - UFZ, Leipzig, 04318, Germany
| | - Jenny Tschörtner
- Systems Biotechnology group, Department of Solar Materials, Helmholtz Centre for Environmental Research - UFZ, Leipzig, 04318, Germany
| | - Andreas Schmid
- Systems Biotechnology group, Department of Solar Materials, Helmholtz Centre for Environmental Research - UFZ, Leipzig, 04318, Germany
| | - Jens O Krömer
- Systems Biotechnology group, Department of Solar Materials, Helmholtz Centre for Environmental Research - UFZ, Leipzig, 04318, Germany
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14
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Tanaka K, Shimakawa G, Kusama S, Harada T, Kato S, Nakanishi S. Ferrihydrite Reduction by Photosynthetic Synechocystis sp. PCC 6803 and Its Correlation With Electricity Generation. Front Microbiol 2021; 12:650832. [PMID: 33763051 PMCID: PMC7982531 DOI: 10.3389/fmicb.2021.650832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/16/2021] [Indexed: 11/29/2022] Open
Abstract
Microbial extracellular electron transfer (EET) to solid-state electron acceptors such as anodes and metal oxides, which was originally identified in dissimilatory metal-reducing bacteria, is a key process in microbial electricity generation and the biogeochemical cycling of metals. Although it is now known that photosynthetic microorganisms can also generate (photo)currents via EET, which has attracted much interest in the field of biophotovoltaics, little is known about the reduction of metal (hydr)oxides via photosynthetic microbial EET. The present work quantitatively assessed the reduction of ferrihydrite in conjunction with the EET of the photosynthetic microbe Synechocystis sp. PCC 6803. Microbial reduction of ferrihydrite was found to be initiated in response to light but proceeded at higher rates when exogenous glucose was added, even under dark conditions. These results indicate that current generation from Synechocystis cells does not always need light irradiation. The qualitative trends exhibited by the ferrihydrite reduction rates under various conditions showed significant correlation with those of the microbial currents. Notably, the maximum concentration of Fe(II) generated by the cyanobacterial cells under dark conditions in the presence of glucose was comparable to the levels observed in the photic layers of Fe-rich microbial mats.
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Affiliation(s)
- Kenya Tanaka
- Graduate School of Engineering Science, Osaka University, Toyonaka, Japan
| | - Ginga Shimakawa
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Shoko Kusama
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Takashi Harada
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Souichiro Kato
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan.,Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Sapporo, Japan
| | - Shuji Nakanishi
- Graduate School of Engineering Science, Osaka University, Toyonaka, Japan.,Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
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15
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Clifford ER, Bradley RW, Wey LT, Lawrence JM, Chen X, Howe CJ, Zhang JZ. Phenazines as model low-midpoint potential electron shuttles for photosynthetic bioelectrochemical systems. Chem Sci 2021; 12:3328-3338. [PMID: 34164103 PMCID: PMC8179378 DOI: 10.1039/d0sc05655c] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/14/2021] [Indexed: 11/21/2022] Open
Abstract
Bioelectrochemical approaches for energy conversion rely on efficient wiring of natural electron transport chains to electrodes. However, state-of-the-art exogenous electron mediators give rise to significant energy losses and, in the case of living systems, long-term cytotoxicity. Here, we explored new selection criteria for exogenous electron mediation by examining phenazines as novel low-midpoint potential molecules for wiring the photosynthetic electron transport chain of the cyanobacterium Synechocystis sp. PCC 6803 to electrodes. We identified pyocyanin (PYO) as an effective cell-permeable phenazine that can harvest electrons from highly reducing points of photosynthesis. PYO-mediated photocurrents were observed to be 4-fold higher than mediator-free systems with an energetic gain of 200 mV compared to the common high-midpoint potential mediator 2,6-dichloro-1,4-benzoquinone (DCBQ). The low-midpoint potential of PYO led to O2 reduction side-reactions, which competed significantly against photocurrent generation; the tuning of mediator concentration was important for outcompeting the side-reactions whilst avoiding acute cytotoxicity. DCBQ-mediated photocurrents were generally much higher but also decayed rapidly and were non-recoverable with fresh mediator addition. This suggests that the cells can acquire DCBQ-resistance over time. In contrast, PYO gave rise to steadier current enhancement despite the co-generation of undesirable reactive oxygen species, and PYO-exposed cells did not develop acquired resistance. Moreover, we demonstrated that the cyanobacteria can be genetically engineered to produce PYO endogenously to improve long-term prospects. Overall, this study established that energetic gains can be achieved via the use of low-potential phenazines in photosynthetic bioelectrochemical systems, and quantifies the factors and trade-offs that determine efficacious mediation in living bioelectrochemical systems.
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Affiliation(s)
- Eleanor R Clifford
- Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Robert W Bradley
- Department of Life Sciences Sir Alexander Fleming Building, Imperial College SW7 2AZ UK
| | - Laura T Wey
- Department of Biochemistry, University of Cambridge Tennis Court Road Cambridge CB2 1QW UK
| | - Joshua M Lawrence
- Department of Biochemistry, University of Cambridge Tennis Court Road Cambridge CB2 1QW UK
| | - Xiaolong Chen
- Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Christopher J Howe
- Department of Biochemistry, University of Cambridge Tennis Court Road Cambridge CB2 1QW UK
| | - Jenny Z Zhang
- Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
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16
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Weliwatte NS, Grattieri M, Minteer SD. Rational design of artificial redox-mediating systems toward upgrading photobioelectrocatalysis. Photochem Photobiol Sci 2021; 20:1333-1356. [PMID: 34550560 PMCID: PMC8455808 DOI: 10.1007/s43630-021-00099-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 09/03/2021] [Indexed: 12/23/2022]
Abstract
Photobioelectrocatalysis has recently attracted particular research interest owing to the possibility to achieve sunlight-driven biosynthesis, biosensing, power generation, and other niche applications. However, physiological incompatibilities between biohybrid components lead to poor electrical contact at the biotic-biotic and biotic-abiotic interfaces. Establishing an electrochemical communication between these different interfaces, particularly the biocatalyst-electrode interface, is critical for the performance of the photobioelectrocatalytic system. While different artificial redox mediating approaches spanning across interdisciplinary research fields have been developed in order to electrically wire biohybrid components during bioelectrocatalysis, a systematic understanding on physicochemical modulation of artificial redox mediators is further required. Herein, we review and discuss the use of diffusible redox mediators and redox polymer-based approaches in artificial redox-mediating systems, with a focus on photobioelectrocatalysis. The future possibilities of artificial redox mediator system designs are also discussed within the purview of present needs and existing research breadth.
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Affiliation(s)
| | - Matteo Grattieri
- Dipartimento Di Chimica, Università Degli Studi Di Bari “Aldo Moro”, Via E. Orabona 4, 70125 Bari, Italy ,IPCF-CNR Istituto Per I Processi Chimico Fisici, Consiglio Nazionale Delle Ricerche, Via E. Orabona 4, 70125 Bari, Italy
| | - Shelley D. Minteer
- Department of Chemistry, University of Utah, Salt Lake City, UT 84112 USA
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17
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Okedi TI, Fisher AC, Yunus K. Quantitative analysis of the effects of morphological changes on extracellular electron transfer rates in cyanobacteria. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:150. [PMID: 32863880 PMCID: PMC7449014 DOI: 10.1186/s13068-020-01788-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 08/13/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Understanding the extracellular electron transport pathways in cyanobacteria is a major factor towards developing biophotovoltaics. Stressing cyanobacteria cells environmentally and then probing changes in physiology or metabolism following a significant change in electron transfer rates is a common approach for investigating the electron path from cell to electrode. However, such studies have not explored how the cells' concurrent morphological adaptations to the applied stresses affect electron transfer rates. In this paper, we establish a ratio to quantify this effect in mediated systems and apply it to Synechococcus elongatus sp. PCC7942 cells grown under different nutritional regimes. RESULTS The results provide evidence that wider and longer cells with larger surface areas have faster mediated electron transfer rates. For rod-shaped cells, increase in cell area as a result of cell elongation more than compensates for the associated decline in mass transfer coefficients, resulting in faster electron transfer. In addition, the results demonstrate that the extent to which morphological adaptations account for the changes in electron transfer rates changes over the bacterial growth cycle, such that investigations probing physiological and metabolic changes are meaningful only at certain time periods. CONCLUSION A simple ratio for quantitatively evaluating the effects of cell morphology adaptations on electron transfer rates has been defined. Furthermore, the study points to engineering cell shape, either via environmental conditioning or genetic engineering, as a potential strategy for improving the performance of biophotovoltaic devices.
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Affiliation(s)
- Tonny I. Okedi
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Phillipa Fawcett Drive, Cambridge, CB3 0AS UK
| | - Adrian C. Fisher
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Phillipa Fawcett Drive, Cambridge, CB3 0AS UK
- Cambridge Center for Advanced Research and Education in Singapore (CARES), 1 Create Way, #05-05 CREATE Tower, Singapore, 138602 Singapore
| | - Kamran Yunus
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Phillipa Fawcett Drive, Cambridge, CB3 0AS UK
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18
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Thirumurthy MA, Hitchcock A, Cereda A, Liu J, Chavez MS, Doss BL, Ros R, El-Naggar MY, Heap JT, Bibby TS, Jones AK. Type IV Pili-Independent Photocurrent Production by the Cyanobacterium Synechocystis sp. PCC 6803. Front Microbiol 2020; 11:1344. [PMID: 32714295 PMCID: PMC7344198 DOI: 10.3389/fmicb.2020.01344] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/26/2020] [Indexed: 11/13/2022] Open
Abstract
Biophotovoltaic devices utilize photosynthetic organisms such as the model cyanobacterium Synechocystis sp. PCC 6803 (Synechocystis) to generate current for power or hydrogen production from light. These devices have been improved by both architecture engineering and genetic engineering of the phototrophic organism. However, genetic approaches are limited by lack of understanding of cellular mechanisms of electron transfer from internal metabolism to the cell exterior. Type IV pili have been implicated in extracellular electron transfer (EET) in some species of heterotrophic bacteria. Furthermore, conductive cell surface filaments have been reported for cyanobacteria, including Synechocystis. However, it remains unclear whether these filaments are type IV pili and whether they are involved in EET. Herein, a mediatorless electrochemical setup is used to compare the electrogenic output of wild-type Synechocystis to that of a ΔpilD mutant that cannot produce type IV pili. No differences in photocurrent, i.e., current in response to illumination, are detectable. Furthermore, measurements of individual pili using conductive atomic force microscopy indicate these structures are not conductive. These results suggest that pili are not required for EET by Synechocystis, supporting a role for shuttling of electrons via soluble redox mediators or direct interactions between the cell surface and extracellular substrates.
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Affiliation(s)
| | - Andrew Hitchcock
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom
| | - Angelo Cereda
- School of Molecular Sciences, Arizona State University, Tempe, AZ, United States
| | - Jiawei Liu
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Marko S. Chavez
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, United States
| | - Bryant L. Doss
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Robert Ros
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Mohamed Y. El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, United States
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
- Department of Chemistry, University of Southern California, Los Angeles, CA, United States
| | - John T. Heap
- Imperial College Centre for Synthetic Biology, Department of Life Sciences, Imperial College London, London, United Kingdom
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Thomas S. Bibby
- Ocean and Earth Science, University of Southampton, Southampton, United Kingdom
| | - Anne K. Jones
- School of Molecular Sciences, Arizona State University, Tempe, AZ, United States
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19
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Grattieri M, Beaver K, Gaffney EM, Dong F, Minteer SD. Advancing the fundamental understanding and practical applications of photo-bioelectrocatalysis. Chem Commun (Camb) 2020; 56:8553-8568. [PMID: 32578607 DOI: 10.1039/d0cc02672g] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Photo-bioelectrocatalysis combines the natural and highly sophisticated process of photosynthesis in biological entities with an abiotic electrode surface, to perform semi-artificial photosynthesis. However, challenges must be overcome, from the establishment and understanding of the photoexcited electron harvesting process at the electrode to the electrochemical characterization of these biotic/abiotic systems, and their subsequent tuning for enhancing energy generation (chemical and/or electrical). This Feature Article discusses the various approaches utilized to tackle these challenges, particularly focusing on powerful multi-disciplinary approaches for understanding and improving photo-bioelectrocatalysis. Among them is the combination of experimental evidence and quantum mechanical calculations, the use of bioinformatics to understand photo-bioelectrocatalysis at a metabolic level, or bioengineering to improve and facilitate photo-bioelectrocatalysis. Key aspects for the future development of photo-bioelectrocatalysis are presented alongside future research needs and promising applications of semi-artificial photosynthesis.
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Affiliation(s)
- Matteo Grattieri
- Department of Chemistry, University of Utah, 315 S 1400 E Rm 2020, Salt Lake City, UT 84112, USA.
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20
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Cohen M, Ozer E, Kushmaro A, Alfonta L. Cellular localization of cytochrome bd in cyanobacteria using genetic code expansion. Biotechnol Bioeng 2019; 117:523-530. [PMID: 31612992 DOI: 10.1002/bit.27194] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/04/2019] [Accepted: 10/06/2019] [Indexed: 11/05/2022]
Abstract
Photosynthesis is one of the most fundamental and complex mechanisms in nature. It is a well-studied process, however, some photosynthetic mechanisms are yet to be deciphered. One of the many proteins that take part in photosynthesis, cytochrome bd, is a terminal oxidase protein that plays a role both in photosynthesis and in respiration in various organisms, specifically, in cyanobacteria. To clarify the role of cytochrome bd in cyanobacteria, a system for the incorporation of an unnatural amino acid into a genomic membrane protein cytochrome bd was constructed in Synechococcus sp. PCC7942. N-propargyl- l-lysine (PrK) was incorporated into mutants of cytochrome bd. Incorporation was verified and the functionality of the mutant cytochrome bd was tested, revealing that both electrochemical and biochemical activities were relatively similar to those of the wild-type protein. The incorporation of PrK was followed by a highly specific labeling and localization of the protein. PrK that was incorporated into the protein enabled a "click" reaction in a bio-orthogonal manner through its alkyne group in a highly specific manner. Cytochrome bd was found to be localized mostly in thylakoid membranes, as was confirmed by an enzyme-linked immunosorbent assay, indicating that our developed localization method is reliable and can be further used to label endogenous proteins in cyanobacteria.
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Affiliation(s)
- Mor Cohen
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Avaram and Stella Goren-Goldstein Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Eden Ozer
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ariel Kushmaro
- Avaram and Stella Goren-Goldstein Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Lital Alfonta
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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21
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Wey LT, Bombelli P, Chen X, Lawrence JM, Rabideau CM, Rowden SJL, Zhang JZ, Howe CJ. The Development of Biophotovoltaic Systems for Power Generation and Biological Analysis. ChemElectroChem 2019; 6:5375-5386. [PMID: 31867153 PMCID: PMC6899825 DOI: 10.1002/celc.201900997] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 08/29/2019] [Indexed: 11/05/2022]
Abstract
Biophotovoltaic systems (BPVs) resemble microbial fuel cells, but utilise oxygenic photosynthetic microorganisms associated with an anode to generate an extracellular electrical current, which is stimulated by illumination. Study and exploitation of BPVs have come a long way over the last few decades, having benefited from several generations of electrode development and improvements in wiring schemes. Power densities of up to 0.5 W m-2 and the powering of small electrical devices such as a digital clock have been reported. Improvements in standardisation have meant that this biophotoelectrochemical phenomenon can be further exploited to address biological questions relating to the organisms. Here, we aim to provide both biologists and electrochemists with a review of the progress of BPV development with a focus on biological materials, electrode design and interfacial wiring considerations, and propose steps for driving the field forward.
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Affiliation(s)
- Laura T. Wey
- Department of BiochemistryUniversity of CambridgeTennis Court RoadCambridgeCB2 1QWUK
| | - Paolo Bombelli
- Department of BiochemistryUniversity of CambridgeTennis Court RoadCambridgeCB2 1QWUK
- Dipartimento di Scienze e Politiche AmbientaliUniversità degli Studi di MilanoMilanItaly
| | - Xiaolong Chen
- Department of ChemistryUniversity of CambridgeLensfield RoadCambridgeCB1 2EWUK
| | - Joshua M. Lawrence
- Department of BiochemistryUniversity of CambridgeTennis Court RoadCambridgeCB2 1QWUK
| | - Clayton M. Rabideau
- Department of BiochemistryUniversity of CambridgeTennis Court RoadCambridgeCB2 1QWUK
- Department of Chemical Engineering and BiotechnologyUniversity of Cambridge Philippa Fawcett DrCambridgeCB3 0ASUK
| | - Stephen J. L. Rowden
- Department of BiochemistryUniversity of CambridgeTennis Court RoadCambridgeCB2 1QWUK
| | - Jenny Z. Zhang
- Department of ChemistryUniversity of CambridgeLensfield RoadCambridgeCB1 2EWUK
| | - Christopher J. Howe
- Department of BiochemistryUniversity of CambridgeTennis Court RoadCambridgeCB2 1QWUK
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22
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Development of a longevous two-species biophotovoltaics with constrained electron flow. Nat Commun 2019; 10:4282. [PMID: 31537786 PMCID: PMC6753107 DOI: 10.1038/s41467-019-12190-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 08/27/2019] [Indexed: 01/07/2023] Open
Abstract
Microbial biophotovoltaics (BPV) offers a biological solution for renewable energy production by using photosynthetic microorganisms as light absorbers. Although abiotic engineering approaches, e.g., electrode modification and device optimization, can enhance the electrochemical communication between living cells and electrodes, the power densities of BPV are still low due to the weak exoelectrogenic activity of photosynthetic microorganisms. Here, we develop a BPV based on a D-lactate mediated microbial consortium consisting of photosynthetic cyanobacteria and exoelectrogenic Shewanella. By directing solar energy from photons to D-lactate, then to electricity, this BPV generates a power density of over 150 mW·m-2 in a temporal separation setup. Furthermore, a spatial-temporal separation setup with medium replenishment enables stable operation for over 40 days with an average power density of 135 mW·m-2. These results demonstrate the electron flow constrained microbial consortium can facilitate electron export from photosynthetic cells and achieve an efficient and durable power output.
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23
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Tschörtner J, Lai B, Krömer JO. Biophotovoltaics: Green Power Generation From Sunlight and Water. Front Microbiol 2019; 10:866. [PMID: 31114551 PMCID: PMC6503001 DOI: 10.3389/fmicb.2019.00866] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/04/2019] [Indexed: 11/29/2022] Open
Abstract
Biophotovoltaics is a relatively new discipline in microbial fuel cell research. The basic idea is the conversion of light energy into electrical energy using photosynthetic microorganisms. The microbes will use their photosynthetic apparatus and the incoming light to split the water molecule. The generated protons and electrons are harvested using a bioelectrochemical system. The key challenge is the extraction of electrons from the microbial electron transport chains into a solid-state anode. On the cathode, a corresponding electrochemical counter reaction will consume the protons and electrons, e.g., through the oxygen reduction to water, or hydrogen formation. In this review, we are aiming to summarize the current state of the art and point out some limitations. We put a specific emphasis on cyanobacteria, as these microbes are considered future workhorses for photobiotechnology and are currently the most widely applied microbes in biophotovoltaics research. Current progress in biophotovoltaics is limited by very low current outputs of the devices while a lack of comparability and standardization of the experimental set-up hinders a systematic optimization of the systems. Nevertheless, the fundamental questions of redox homeostasis in photoautotrophs and the potential to directly harvest light energy from a highly efficient photosystem, rather than through oxidation of inefficiently produced biomass are highly relevant aspects of biophotovoltaics.
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Affiliation(s)
| | | | - Jens O. Krömer
- Systems Biotechnology, Department of Solar Materials, Helmholtz Centre for Environmental Research, Leipzig, Germany
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24
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Schorsch M, Kramer M, Goss T, Eisenhut M, Robinson N, Osman D, Wilde A, Sadaf S, Brückler H, Walder L, Scheibe R, Hase T, Hanke GT. A unique ferredoxin acts as a player in the low-iron response of photosynthetic organisms. Proc Natl Acad Sci U S A 2018; 115:E12111-E12120. [PMID: 30514818 PMCID: PMC6304933 DOI: 10.1073/pnas.1810379115] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Iron chronically limits aquatic photosynthesis, especially in marine environments, and the correct perception and maintenance of iron homeostasis in photosynthetic bacteria, including cyanobacteria, is therefore of global significance. Multiple adaptive mechanisms, responsive promoters, and posttranscriptional regulators have been identified, which allow cyanobacteria to respond to changing iron concentrations. However, many factors remain unclear, in particular, how iron status is perceived within the cell. Here we describe a cyanobacterial ferredoxin (Fed2), with a unique C-terminal extension, that acts as a player in iron perception. Fed2 homologs are highly conserved in photosynthetic organisms from cyanobacteria to higher plants, and, although they belong to the plant type ferredoxin family of [2Fe-2S] photosynthetic electron carriers, they are not involved in photosynthetic electron transport. As deletion of fed2 appears lethal, we developed a C-terminal truncation system to attenuate protein function. Disturbed Fed2 function resulted in decreased chlorophyll accumulation, and this was exaggerated in iron-depleted medium, where different truncations led to either exaggerated or weaker responses to low iron. Despite this, iron concentrations remained the same, or were elevated in all truncation mutants. Further analysis established that, when Fed2 function was perturbed, the classical iron limitation marker IsiA failed to accumulate at transcript and protein levels. By contrast, abundance of IsiB, which shares an operon with isiA, was unaffected by loss of Fed2 function, pinpointing the site of Fed2 action in iron perception to the level of posttranscriptional regulation.
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Affiliation(s)
- Michael Schorsch
- School of Biological and Chemical Sciences, Queen Mary University of London, E1 4NS London, United Kingdom
| | - Manuela Kramer
- School of Biological and Chemical Sciences, Queen Mary University of London, E1 4NS London, United Kingdom
| | - Tatjana Goss
- Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Marion Eisenhut
- Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Nigel Robinson
- Department of Biosciences, Durham University, DH1 3LE Durham, United Kingdom
| | - Deenah Osman
- Department of Biosciences, Durham University, DH1 3LE Durham, United Kingdom
| | - Annegret Wilde
- Institute of Biology III, University of Freiburg, 79104 Freiburg, Germany
| | - Shamaila Sadaf
- Institute of Chemistry of New Materials, University of Osnabrück, 49069 Osnabrück, Germany
| | - Hendrik Brückler
- Institute of Chemistry of New Materials, University of Osnabrück, 49069 Osnabrück, Germany
| | - Lorenz Walder
- Institute of Chemistry of New Materials, University of Osnabrück, 49069 Osnabrück, Germany
| | - Renate Scheibe
- Plant Physiology, University of Osnabrück, 49076 Osnabrück, Germany
| | - Toshiharu Hase
- Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | - Guy T Hanke
- School of Biological and Chemical Sciences, Queen Mary University of London, E1 4NS London, United Kingdom;
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25
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Longatte G, Sayegh A, Delacotte J, Rappaport F, Wollman FA, Guille-Collignon M, Lemaître F. Investigation of photocurrents resulting from a living unicellular algae suspension with quinones over time. Chem Sci 2018; 9:8271-8281. [PMID: 30542576 PMCID: PMC6238620 DOI: 10.1039/c8sc03058h] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 08/31/2018] [Indexed: 02/03/2023] Open
Abstract
Plants, algae, and some bacteria convert solar energy into chemical energy by using photosynthesis. In light of the current energy environment, many research strategies try to benefit from photosynthesis in order to generate usable photobioelectricity. Among all the strategies developed for transferring electrons from the photosynthetic chain to an outer collecting electrode, we recently implemented a method on a preparative scale (high surface electrode) based on a Chlamydomonas reinhardtii green algae suspension in the presence of exogenous quinones as redox mediators. While giving rise to an interesting performance (10-60 μA cm-2) in the course of one hour, this device appears to cause a slow decrease of the recorded photocurrent. In this paper, we wish to analyze and understand this gradual fall in performance in order to limit this issue in future applications. We thus first show that this kind of degradation could be related to over-irradiation conditions or side-effects of quinones depending on experimental conditions. We therefore built an empirical model involving a kinetic quenching induced by incubation with quinones, which is globally consistent with the experimental data provided by fluorescence measurements achieved after dark incubation of algae in the presence of quinones.
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Affiliation(s)
- Guillaume Longatte
- PASTEUR , Département de chimie , École Normale Supérieure , PSL University , Sorbonne Université , CNRS , 75005 Paris , France . ;
| | - Adnan Sayegh
- PASTEUR , Département de chimie , École Normale Supérieure , PSL University , Sorbonne Université , CNRS , 75005 Paris , France . ;
| | - Jérôme Delacotte
- PASTEUR , Département de chimie , École Normale Supérieure , PSL University , Sorbonne Université , CNRS , 75005 Paris , France . ;
| | - Fabrice Rappaport
- Laboratory of Membrane and Molecular Physiology at IBPC , UMR7141 CNRS/ Sorbonne Université , 13 rue Pierre et Marie Curie , 75005 Paris , France
| | - Francis-André Wollman
- Laboratory of Membrane and Molecular Physiology at IBPC , UMR7141 CNRS/ Sorbonne Université , 13 rue Pierre et Marie Curie , 75005 Paris , France
| | - Manon Guille-Collignon
- PASTEUR , Département de chimie , École Normale Supérieure , PSL University , Sorbonne Université , CNRS , 75005 Paris , France . ;
| | - Frédéric Lemaître
- PASTEUR , Département de chimie , École Normale Supérieure , PSL University , Sorbonne Université , CNRS , 75005 Paris , France . ;
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26
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Saper G, Kallmann D, Conzuelo F, Zhao F, Tóth TN, Liveanu V, Meir S, Szymanski J, Aharoni A, Schuhmann W, Rothschild A, Schuster G, Adir N. Live cyanobacteria produce photocurrent and hydrogen using both the respiratory and photosynthetic systems. Nat Commun 2018; 9:2168. [PMID: 29867170 PMCID: PMC5986869 DOI: 10.1038/s41467-018-04613-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Accepted: 05/04/2018] [Indexed: 01/26/2023] Open
Abstract
Oxygenic photosynthetic organisms perform solar energy conversion of water and CO2 to O2 and sugar at a broad range of wavelengths and light intensities. These cells also metabolize sugars using a respiratory system that functionally overlaps the photosynthetic apparatus. In this study, we describe the harvesting of photocurrent used for hydrogen production from live cyanobacteria. A non-harmful gentle physical treatment of the cyanobacterial cells enables light-driven electron transfer by an endogenous mediator to a graphite electrode in a bio-photoelectrochemical cell, without the addition of sacrificial electron donors or acceptors. We show that the photocurrent is derived from photosystem I and that the electrons originate from carbohydrates digested by the respiratory system. Finally, the current is utilized for hydrogen evolution on the cathode at a bias of 0.65 V. Taken together, we present a bio-photoelectrochemical system where live cyanobacteria produce stable photocurrent that can generate hydrogen. Biologically ### produced electrical currents and hydrogen are new energy sources. Here, the authors find that low presser microfluidizer treatment produced cyanobacterium that can utilize electrons from respiratory and photosynthesis to promote current and hydrogen generation, without the addition of exogenous electron mediators.
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Affiliation(s)
- Gadiel Saper
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel
| | - Dan Kallmann
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel
| | - Felipe Conzuelo
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Ruhr-Universität Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Fangyuan Zhao
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Ruhr-Universität Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Tünde N Tóth
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel.,Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel
| | - Varda Liveanu
- Faculty of Biology, Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel
| | - Sagit Meir
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Jedrzej Szymanski
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel.,Leibniz Institute of Plant Genetics and Crop Research (IPK), Network Analysis and Modelling, OT Gatersleben, 06466, Seeland, Germany
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Wolfgang Schuhmann
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Ruhr-Universität Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Avner Rothschild
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel.,Department of Materials Science and Engineering, Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel
| | - Gadi Schuster
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel. .,Faculty of Biology, Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel.
| | - Noam Adir
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel. .,Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel.
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27
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Porous translucent electrodes enhance current generation from photosynthetic biofilms. Nat Commun 2018; 9:1299. [PMID: 29610519 PMCID: PMC5880806 DOI: 10.1038/s41467-018-03320-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Accepted: 02/05/2018] [Indexed: 11/24/2022] Open
Abstract
Some photosynthetically active bacteria transfer electrons across their membranes, generating electrical photocurrents in biofilms. Devices harvesting solar energy by this mechanism are currently limited by the charge transfer to the electrode. Here, we report the enhancement of bioelectrochemical photocurrent harvesting using electrodes with porosities on the nanometre and micrometre length scale. For the cyanobacteria Nostoc punctiforme and Synechocystis sp. PCC6803 on structured indium-tin-oxide electrodes, an increase in current generation by two orders of magnitude is observed compared to a non-porous electrode. In addition, the photo response is substantially faster compared to non-porous anodes. Electrodes with large enough mesopores for the cells to inhabit show only a small advantage over purely nanoporous electrode morphologies, suggesting the prevalence of a redox shuttle mechanism in the electron transfer from the bacteria to the electrode over a direct conduction mechanism. Our results highlight the importance of electrode nanoporosity in the design of electrochemical bio-interfaces. Some microorganisms are able to generate electrons that can be externally harvested. Here the authors show an increase by two orders of magnitude in the photocurrent when two cyanobacterial strains are grown on nanopourous transparent conducting substrates, compared to traditional solid substrates.
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28
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Esteves-Ferreira AA, Inaba M, Fort A, Araújo WL, Sulpice R. Nitrogen metabolism in cyanobacteria: metabolic and molecular control, growth consequences and biotechnological applications. Crit Rev Microbiol 2018. [DOI: 10.1080/1040841x.2018.1446902] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Alberto A. Esteves-Ferreira
- National University of Ireland – Galway, Plant Systems Biology Lab, School of Natural Sciences, Plant and AgriBiosciences Research Centre, Galway, Ireland
- CAPES Foundation, Ministry of Education of Brazil, Brasilia, Brazil
| | - Masami Inaba
- National University of Ireland – Galway, Plant Systems Biology Lab, School of Natural Sciences, Plant and AgriBiosciences Research Centre, Galway, Ireland
| | - Antoine Fort
- National University of Ireland – Galway, Plant Systems Biology Lab, School of Natural Sciences, Plant and AgriBiosciences Research Centre, Galway, Ireland
| | - Wagner L. Araújo
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Ronan Sulpice
- National University of Ireland – Galway, Plant Systems Biology Lab, School of Natural Sciences, Plant and AgriBiosciences Research Centre, Galway, Ireland
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29
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Gonzalez-Aravena AC, Yunus K, Zhang L, Norling B, Fisher AC. Tapping into cyanobacteria electron transfer for higher exoelectrogenic activity by imposing iron limited growth. RSC Adv 2018; 8:20263-20274. [PMID: 35541668 PMCID: PMC9080828 DOI: 10.1039/c8ra00951a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 05/14/2018] [Indexed: 11/21/2022] Open
Abstract
The exoelectrogenic capacity of the cyanobacterium Synechococcus elongatus PCC7942 was studied in iron limited growth in order to establish conditions favouring extracellular electron transfer in cyanobacteria for photo-bioelectricity generation. Investigation into extracellular reduction of ferricyanide by Synechococcus elongatus PCC7942 demonstrated enhanced capability for the iron limited conditions in comparison to the iron sufficient conditions. Furtheremore, the significance of pH showed that higher rates of ferricyanide reduction occurred at pH 7, with a 2.7-fold increase with respect to pH 9.5 for iron sufficient cultures and 24-fold increase for iron limited cultures. The strategy presented induced exoelectrogenesis driven mainly by photosynthesis and an estimated redirection of the 28% of electrons from photosynthetic activity was achieved by the iron limited conditions. In addition, ferricyanide reduction in the dark by iron limited cultures also presented a significant improvement, with a 6-fold increase in comparison to iron sufficient cultures. Synechococcus elongatus PCC7942 ferricyanide reduction rates are unprecedented for cyanobacteria and they are comparable to those of microalgae. The redox activity of biofilms directly on ITO-coated glass, in the absence of any artificial mediator, was also enhanced under the iron limited conditions, implying that iron limitation increased exoelectrogenesis at the outer membrane level. Cyclic voltammetry of Synechococcus elongatus PCC7942 biofilms on ITO-coated glass showed a midpoint potential around 0.22 V vs. Ag/AgCl and iron limited biofilms had the capability to sustain currents in a saturated-like fashion. The present work proposes an iron related exoelectrogenic capacity of Synechococcus elongatus PCC7942 and sets a starting point for the study of this strain in order to improve photo-bioelectricity and dark-bioelectricity generation by cyanobacteria, including more sustainable mediatorless systems. Iron limited growth induces unprecedented rates of extracellular electron transport in cyanobacteria delivering enhanced photosynthesis driven bioelectricity in electrochemical platforms.![]()
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Affiliation(s)
| | - K. Yunus
- Department of Chemical Engineering and Biotechnology
- University of Cambridge
- Cambridge
- UK
| | - L. Zhang
- School of Biological Sciences
- Nanyang Technological University
- Singapore
| | - B. Norling
- School of Biological Sciences
- Nanyang Technological University
- Singapore
| | - A. C. Fisher
- Department of Chemical Engineering and Biotechnology
- University of Cambridge
- Cambridge
- UK
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30
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Rowden SJL, Bombelli P, Howe CJ. Biophotovoltaics: Design and Study of Bioelectrochemical Systems for Biotechnological Applications and Metabolic Investigation. Methods Mol Biol 2018; 1770:335-346. [PMID: 29978412 DOI: 10.1007/978-1-4939-7786-4_20] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Biophotovoltaic methods rely on the fact that photosynthetic microorganisms, like many others, can export small amounts of electric current. For photosynthetic organisms, this current usually increases on illumination. This "exoelectrogenic" property may be of biotechnological interest, and may also provide useful experimental insights into the physiological status of the cell. We describe how to construct biophotovoltaic devices, and the kinds of measurements that are typically made.
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Affiliation(s)
- Stephen J L Rowden
- Department of Biochemistry, University of Cambridge, Cambridge, UK
- Faculty of Engineering and Science, University of Greenwich, Kent, UK
| | - Paolo Bombelli
- Department of Biochemistry, University of Cambridge, Cambridge, UK
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31
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Schuergers N, Werlang C, Ajo-Franklin CM, Boghossian AA. A Synthetic Biology Approach to Engineering Living Photovoltaics. ENERGY & ENVIRONMENTAL SCIENCE 2017; 10:1102-1115. [PMID: 28694844 PMCID: PMC5501249 DOI: 10.1039/c7ee00282c] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The ability to electronically interface living cells with electron accepting scaffolds is crucial for the development of next-generation biophotovoltaic technologies. Although recent studies have focused on engineering synthetic interfaces that can maximize electronic communication between the cell and scaffold, the efficiency of such devices is limited by the low conductivity of the cell membrane. This review provides a materials science perspective on applying a complementary, synthetic biology approach to engineering membrane-electrode interfaces. It focuses on the technical challenges behind the introduction of foreign extracellular electron transfer pathways in bacterial host cells and the past and future efforts to engineer photosynthetic organisms with artificial electron-export capabilities for biophotovoltaic applications. The article highlights advances in engineering protein-based, electron-exporting conduits in a model host organism, E. coli, before reviewing state-of-the-art biophotovoltaic technologies that use both unmodified and bioengineered photosynthetic bacteria with improved electron transport capabilities. A thermodynamic analysis is used to propose an energetically feasible pathway for extracellular electron transport in engineered cyanobacteria and identify metabolic bottlenecks amenable to protein engineering techniques. Based on this analysis, an engineered photosynthetic organism expressing a foreign, protein-based electron conduit yields a maximum theoretical solar conversion efficiency of 6-10% without accounting for additional bioengineering optimizations for light-harvesting.
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Affiliation(s)
- N. Schuergers
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - C. Werlang
- Interschool Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - C. M. Ajo-Franklin
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Synthetic Biology Institute, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - A. A. Boghossian
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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32
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Longatte G, Rappaport F, Wollman FA, Guille-Collignon M, Lemaître F. Electrochemical Harvesting of Photosynthetic Electrons from Unicellular Algae Population at the Preparative Scale by Using 2,6-dichlorobenzoquinone. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.03.124] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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33
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Esteves-Ferreira AA, Cavalcanti JHF, Vaz MGMV, Alvarenga LV, Nunes-Nesi A, Araújo WL. Cyanobacterial nitrogenases: phylogenetic diversity, regulation and functional predictions. Genet Mol Biol 2017; 40:261-275. [PMID: 28323299 PMCID: PMC5452144 DOI: 10.1590/1678-4685-gmb-2016-0050] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 12/21/2016] [Indexed: 12/21/2022] Open
Abstract
Cyanobacteria is a remarkable group of prokaryotic photosynthetic microorganisms, with several genera capable of fixing atmospheric nitrogen (N2) and presenting a wide range of morphologies. Although the nitrogenase complex is not present in all cyanobacterial taxa, it is spread across several cyanobacterial strains. The nitrogenase complex has also a high theoretical potential for biofuel production, since H2 is a by-product produced during N2 fixation. In this review we discuss the significance of a relatively wide variety of cell morphologies and metabolic strategies that allow spatial and temporal separation of N2 fixation from photosynthesis in cyanobacteria. Phylogenetic reconstructions based on 16S rRNA and nifD gene sequences shed light on the evolutionary history of the two genes. Our results demonstrated that (i) sequences of genes involved in nitrogen fixation (nifD) from several morphologically distinct strains of cyanobacteria are grouped in similarity with their morphology classification and phylogeny, and (ii) nifD genes from heterocytous strains share a common ancestor. By using this data we also discuss the evolutionary importance of processes such as horizontal gene transfer and genetic duplication for nitrogenase evolution and diversification. Finally, we discuss the importance of H2 synthesis in cyanobacteria, as well as strategies and challenges to improve cyanobacterial H2 production.
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Affiliation(s)
- Alberto A Esteves-Ferreira
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.,Max-Planck-partner group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - João Henrique Frota Cavalcanti
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.,Max-Planck-partner group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Marcelo Gomes Marçal Vieira Vaz
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.,Max-Planck-partner group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Luna V Alvarenga
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.,Max-Planck-partner group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.,Max-Planck-partner group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.,Max-Planck-partner group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
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34
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Halan B, Tschörtner J, Schmid A. Generating Electric Current by Bioartificial Photosynthesis. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2017; 167:361-393. [PMID: 29224082 DOI: 10.1007/10_2017_44] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Abundant solar energy can be a sustainable source of energy. This chapter highlights recent advancements, challenges, and future scenarios in bioartificial photosynthesis, which is a new subset of bioelectrochemical systems (BESs) and technologies. BES technologies exploit the catalytic interactions between biological moieties and electrodes. At the nexus of BES and photovoltaics, this review focuses on light-harvesting technologies based on bioartificial photosynthesis. Such technologies are promising because electrical energy is generated from sunlight and water without the need for additional organic feedstock. This review focuses on photosynthetic electron generation and transfer and compares the current status of bioartificial photosynthesis with other artificial systems that mimic the chemistry of photosynthetic energy transformation.The fundamental principles and the operation of functional units of bioartificial photosynthesis are addressed. Selected photobioelectrochemical systems employed to obtain light-driven electric currents from photosynthetic organisms are presented. The achievable current output and theoretical maxima are revisited by conceptualizing operational and process window techniques. Factors affecting overall photocurrent efficiency, performance limitations, and scaleup bottlenecks are highlighted in view of enhancing the energy conversion efficiency of photobioelectrochemical systems. To finish, the challenges associated with bioartificial photosynthetic technologies are outlined. Graphical Abstract Operational window for (bio-)artificial photosynthesis. Green circle in the upper right corner: development objective for research and engineering efforts.
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Affiliation(s)
- Babu Halan
- Department of Solar Materials, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Germany
| | - Jenny Tschörtner
- Department of Solar Materials, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Germany
| | - Andreas Schmid
- Department of Solar Materials, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Germany.
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35
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Ciniciato GPMK, Ng FL, Phang SM, Jaafar MM, Fisher AC, Yunus K, Periasamy V. Investigating the association between photosynthetic efficiency and generation of biophotoelectricity in autotrophic microbial fuel cells. Sci Rep 2016; 6:31193. [PMID: 27502051 PMCID: PMC4977534 DOI: 10.1038/srep31193] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 07/14/2016] [Indexed: 11/09/2022] Open
Abstract
Microbial fuel cells operating with autotrophic microorganisms are known as biophotovoltaic devices. It represents a great opportunity for environmentally-friendly power generation using the energy of the sunlight. The efficiency of electricity generation in this novel system is however low. This is partially reflected by the poor understanding of the bioelectrochemical mechanisms behind the electron transfer from these microorganisms to the electrode surface. In this work, we propose a combination of electrochemical and fluorescence techniques, giving emphasis to the pulse amplitude modulation fluorescence. The combination of these two techniques allow us to obtain information that can assist in understanding the electrical response obtained from the generation of electricity through the intrinsic properties related to the photosynthetic efficiency that can be obtained from the fluorescence emitted. These were achieved quantitatively by means of observed changes in four photosynthetic parameters with the bioanode generating electricity. These are the maximum quantum yield (Fv/Fm), alpha (α), light saturation coefficient (Ek) and maximum rate of electron transfer (rETRm). The relationship between the increases in the current density collected by the bioanode to the decrease of the rETRm values in the photosynthetic pathway for the two microorganisms was also discussed.
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Affiliation(s)
- Gustavo P M K Ciniciato
- Institute of Ocean and Earth Sciences (IOES), University of Malaya, 50603 Kuala Lumpur, Malaysia.,Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, CB2 3RA Cambridge, United Kingdom
| | - Fong-Lee Ng
- Institute of Ocean and Earth Sciences (IOES), University of Malaya, 50603 Kuala Lumpur, Malaysia.,Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Siew-Moi Phang
- Institute of Ocean and Earth Sciences (IOES), University of Malaya, 50603 Kuala Lumpur, Malaysia.,Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Muhammad Musoddiq Jaafar
- Low Dimensional Materials Research Centre (LDMRC), Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Adrian C Fisher
- Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, CB2 3RA Cambridge, United Kingdom
| | - Kamran Yunus
- Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, CB2 3RA Cambridge, United Kingdom
| | - Vengadesh Periasamy
- Low Dimensional Materials Research Centre (LDMRC), Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia
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36
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37
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Lea-Smith DJ, Vasudevan R, Howe CJ. Generation of Marked and Markerless Mutants in Model Cyanobacterial Species. J Vis Exp 2016. [PMID: 27286310 DOI: 10.3791/54001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Cyanobacteria are ecologically important organisms and potential platforms for production of biofuels and useful industrial products. Genetic manipulation of cyanobacteria, especially model organisms such as Synechocystis sp. PCC6803 and Synechococcus sp. PCC7002, is a key tool for both basic and applied research. Generation of unmarked mutants, whereby chromosomal alterations are introduced into a strain via insertion of an antibiotic resistance cassette (a manipulatable fragment of DNA containing one or more genes), followed by subsequent removal of this cassette using a negative selectable marker, is a particularly powerful technique. Unmarked mutants can be repeatedly genetically manipulated, allowing as many alterations to be introduced into a strain as desired. In addition, the absence of genes encoding antibiotic resistance proteins in the mutated strain is desirable, as it avoids the possibility of 'escape' of antibiotic resistant organisms into the environment. However, detailed methods for repeated rounds of genetic manipulation of cyanobacteria are not well described in the scientific literature. Here we provide a comprehensive description of this technique, which we have successfully used to generate mutants with multiple deletions, single point mutations within a gene of interest and insertion of novel gene cassettes.
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38
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Schneider K, Thorne RJ, Cameron PJ. An investigation of anode and cathode materials in photomicrobial fuel cells. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2016; 374:rsta.2015.0080. [PMID: 26755764 DOI: 10.1098/rsta.2015.0080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/16/2015] [Indexed: 06/05/2023]
Abstract
Photomicrobial fuel cells (p-MFCs) are devices that use photosynthetic organisms (such as cyanobacteria or algae) to turn light energy into electrical energy. In a p-MFC, the anode accepts electrons from microorganisms that are either growing directly on the anode surface (biofilm) or are free floating in solution (planktonic). The nature of both the anode and cathode material is critical for device efficiency. An ideal anode is biocompatible and facilitates direct electron transfer from the microorganisms, with no need for an electron mediator. For a p-MFC, there is the additional requirement that the anode should not prevent light from perfusing through the photosynthetic cells. The cathode should facilitate the rapid reaction of protons and oxygen to form water so as not to rate limit the device. In this paper, we first review the range of anode and cathode materials currently used in p-MFCs. We then present our own data comparing cathode materials in a p-MFC and our first results using porous ceramic anodes in a mediator-free p-MFC.
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Affiliation(s)
| | - Rebecca J Thorne
- Department of Environmental Impacts and Economics (IMPEC), Norwegian Institute for Air Research (NILU), PO Box 100, 2027 Kjeller, Norway
| | - Petra J Cameron
- Department of Chemistry, University of Bath, Bath BA2 7AY, UK
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39
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Longatte G, Rappaport F, Wollman FA, Guille-Collignon M, Lemaître F. Mechanism and analyses for extracting photosynthetic electrons using exogenous quinones – what makes a good extraction pathway? Photochem Photobiol Sci 2016; 15:969-79. [DOI: 10.1039/c6pp00076b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The extraction of photosynthetic electrons by exogenous quinones on unicellular green algae was investigated with fluorescence measurements. Zone diagrams were built for defining the most appropriate harvesting conditions.
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Affiliation(s)
- G. Longatte
- Ecole normale supérieure
- PSL Research University
- UPMC Univ Paris 06
- CNRS
- Département de Chimie
| | - F. Rappaport
- Laboratoire de physiologie membranaire et moléculaire du chloroplaste
- CNRS
- UPMC UMR 7141
- I.B.PC
- 75005 Paris
| | - F.-A. Wollman
- Laboratoire de physiologie membranaire et moléculaire du chloroplaste
- CNRS
- UPMC UMR 7141
- I.B.PC
- 75005 Paris
| | - M. Guille-Collignon
- Ecole normale supérieure
- PSL Research University
- UPMC Univ Paris 06
- CNRS
- Département de Chimie
| | - F. Lemaître
- Ecole normale supérieure
- PSL Research University
- UPMC Univ Paris 06
- CNRS
- Département de Chimie
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40
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Photosynthetic, respiratory and extracellular electron transport pathways in cyanobacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1857:247-55. [PMID: 26498190 DOI: 10.1016/j.bbabio.2015.10.007] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Revised: 10/09/2015] [Accepted: 10/14/2015] [Indexed: 01/05/2023]
Abstract
Cyanobacteria have evolved elaborate electron transport pathways to carry out photosynthesis and respiration, and to dissipate excess energy in order to limit cellular damage. Our understanding of the complexity of these systems and their role in allowing cyanobacteria to cope with varying environmental conditions is rapidly improving, but many questions remain. We summarize current knowledge of cyanobacterial electron transport pathways, including the possible roles of alternative pathways in photoprotection. We describe extracellular electron transport, which is as yet poorly understood. Biological photovoltaic devices, which measure electron output from cells, and which have been proposed as possible means of renewable energy generation, may be valuable tools in understanding cyanobacterial electron transfer pathways, and enhanced understanding of electron transfer may allow improvements in the efficiency of power output. This article is part of a Special Issue entitled Organization and dynamics of bioenergetic systems in bacteria, edited by Conrad Mullineaux.
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41
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Sekar N, Jain R, Yan Y, Ramasamy RP. Enhanced photo-bioelectrochemical energy conversion by genetically engineered cyanobacteria. Biotechnol Bioeng 2015; 113:675-9. [PMID: 26348367 DOI: 10.1002/bit.25829] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/21/2015] [Accepted: 09/01/2015] [Indexed: 12/22/2022]
Abstract
Photosynthetic energy conversion using natural systems is increasingly being investigated in the recent years. Photosynthetic microorganisms, such as cyanobacteria, exhibit light-dependent electrogenic characteristics in photo-bioelectrochemical cells (PBEC) that generate substantial photocurrents, yet the current densities are lower than their photovoltaic counterparts. Recently, we demonstrated that a cyanobacterium named Nostoc sp. employed in PBEC could generate up to 35 mW m(-2) even in a non-engineered PBEC. With the insights obtained from our previous research, a novel and successful attempt has been made in the current study to genetically engineer the cyanobacteria to further enhance its extracellular electron transfer. The cyanobacterium Synechococcus elongatus PCC 7942 was genetically engineered to express a non-native redox protein called outer membrane cytochrome S (OmcS). OmcS is predominantly responsible for metal reducing abilities of exoelectrogens such as Geobacter sp. The engineered S. elongatus exhibited higher extracellular electron transfer ability resulting in approximately ninefold higher photocurrent generation on the anode of a PBEC than the corresponding wild-type cyanobacterium. This work highlights the scope for enhancing photocurrent generation in cyanobacteria, thereby benefiting faster advancement of the photosynthetic microbial fuel cell technology.
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Affiliation(s)
- Narendran Sekar
- Nano Electrochemistry Laboratory, College of Engineering, University of Georgia, Athens, Georgia, 30602
| | - Rachit Jain
- Biosynthetic Engineering and Biocatalysis Laboratory, College of Engineering, University of Georgia, Athens, Georgia
| | - Yajun Yan
- Biosynthetic Engineering and Biocatalysis Laboratory, College of Engineering, University of Georgia, Athens, Georgia
| | - Ramaraja P Ramasamy
- Nano Electrochemistry Laboratory, College of Engineering, University of Georgia, Athens, Georgia, 30602.
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42
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Iron reduction by the cyanobacterium Synechocystis sp. PCC 6803. Bioelectrochemistry 2015; 105:103-9. [PMID: 26079619 DOI: 10.1016/j.bioelechem.2015.05.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 05/21/2015] [Accepted: 05/31/2015] [Indexed: 11/22/2022]
Abstract
Synechocystis sp. PCC 6803 uptakes iron using a reductive mechanism, similar to that exhibited by many other microalgae. Various bio-electrochemical technologies have made use of this reductive cellular capacity, but there is still a lack of fundamental understanding of cellular reduction rates under different conditions. This study used electrochemical techniques to further investigate the reductive interactions of Synechocystis cells with Fe(III) from the iron species potassium ferricyanide, with varying cell and ferricyanide concentrations present. At the lowest cell concentrations tested, cell reduction machinery appeared to kinetically limit the reduction reaction, but ferricyanide reduction rates were mass transport controlled at the higher cell and ferricyanide concentrations studied. Improving the understanding of the reduction of Fe(III) by whole cyanobacterial cells is important for improving the efficiencies of technologies that rely on this interaction.
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Bombelli P, Müller T, Herling TW, Howe CJ, Knowles TPJ. A High Power-Density, Mediator-Free, Microfluidic Biophotovoltaic Device for Cyanobacterial Cells. ADVANCED ENERGY MATERIALS 2015; 5:1-6. [PMID: 26190957 PMCID: PMC4503997 DOI: 10.1002/aenm.201401299] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Indexed: 05/19/2023]
Abstract
Biophotovoltaics has emerged as a promising technology for generating renewable energy because it relies on living organisms as inexpensive, self-repairing, and readily available catalysts to produce electricity from an abundant resource: sunlight. The efficiency of biophotovoltaic cells, however, has remained significantly lower than that achievable through synthetic materials. Here, a platform is devised to harness the large power densities afforded by miniaturized geometries. To this effect, a soft-lithography approach is developed for the fabrication of microfluidic biophotovoltaic devices that do not require membranes or mediators. Synechocystis sp. PCC 6803 cells are injected and allowed to settle on the anode, permitting the physical proximity between cells and electrode required for mediator-free operation. Power densities of above 100 mW m-2 are demonstrated for a chlorophyll concentration of 100 μM under white light, which is a high value for biophotovoltaic devices without extrinsic supply of additional energy.
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Affiliation(s)
- Paolo Bombelli
- Department of Biochemistry, University of Cambridge, Tennis
Court RoadCambridge, CB2 1QW, UK
| | - Thomas Müller
- Department of Chemistry, University of Cambridge, Lensfield
RoadCambridge, CB2 1EW, UK
| | - Therese W Herling
- Department of Chemistry, University of Cambridge, Lensfield
RoadCambridge, CB2 1EW, UK
| | - Christopher J Howe
- Department of Biochemistry, University of Cambridge, Tennis
Court RoadCambridge, CB2 1QW, UK
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Lea-Smith DJ, Bombelli P, Dennis JS, Scott SA, Smith AG, Howe CJ. Phycobilisome-Deficient Strains of Synechocystis sp. PCC 6803 Have Reduced Size and Require Carbon-Limiting Conditions to Exhibit Enhanced Productivity. PLANT PHYSIOLOGY 2014; 165:705-714. [PMID: 24760817 PMCID: PMC4044857 DOI: 10.1104/pp.114.237206] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 04/17/2014] [Indexed: 05/21/2023]
Abstract
Reducing excessive light harvesting in photosynthetic organisms may increase biomass yields by limiting photoinhibition and increasing light penetration in dense cultures. The cyanobacterium Synechocystis sp. PCC 6803 harvests light via the phycobilisome, which consists of an allophycocyanin core and six radiating rods, each with three phycocyanin (PC) discs. Via targeted gene disruption and alterations to the promoter region, three mutants with two (pcpcT→C) and one (ΔCpcC1C2:pcpcT→C) PC discs per rod or lacking PC (olive) were generated. Photoinhibition and chlorophyll levels decreased upon phycobilisome reduction, although greater penetration of white light was observed only in the PC-deficient mutant. In all strains cultured at high cell densities, most light was absorbed by the first 2 cm of the culture. Photosynthesis and respiration rates were also reduced in the ΔCpcC1C2:pcpcT→C and olive mutants. Cell size was smaller in the pcpcT→C and olive strains. Growth and biomass accumulation were similar between the wild-type and pcpcT→C under a variety of conditions. Growth and biomass accumulation of the olive mutant were poorer in carbon-saturated cultures but improved in carbon-limited cultures at higher light intensities, as they did in the ΔCpcC1C2:pcpcT→C mutant. This study shows that one PC disc per rod is sufficient for maximal light harvesting and biomass accumulation, except under conditions of high light and carbon limitation, and two or more are sufficient for maximal oxygen evolution. To our knowledge, this study is the first to measure light penetration in bulk cultures of cyanobacteria and offers important insights into photobioreactor design.
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Affiliation(s)
- David J Lea-Smith
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom (D.J.L.-S., P.B., C.J.H.);Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA, United Kingdom (J.S.D.);Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom (S.A.S.); andDepartment of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (A.G.S.)
| | - Paolo Bombelli
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom (D.J.L.-S., P.B., C.J.H.);Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA, United Kingdom (J.S.D.);Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom (S.A.S.); andDepartment of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (A.G.S.)
| | - John S Dennis
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom (D.J.L.-S., P.B., C.J.H.);Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA, United Kingdom (J.S.D.);Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom (S.A.S.); andDepartment of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (A.G.S.)
| | - Stuart A Scott
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom (D.J.L.-S., P.B., C.J.H.);Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA, United Kingdom (J.S.D.);Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom (S.A.S.); andDepartment of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (A.G.S.)
| | - Alison G Smith
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom (D.J.L.-S., P.B., C.J.H.);Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA, United Kingdom (J.S.D.);Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom (S.A.S.); andDepartment of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (A.G.S.)
| | - Christopher J Howe
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom (D.J.L.-S., P.B., C.J.H.);Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA, United Kingdom (J.S.D.);Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom (S.A.S.); andDepartment of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (A.G.S.)
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Cereda A, Hitchcock A, Symes MD, Cronin L, Bibby TS, Jones AK. A bioelectrochemical approach to characterize extracellular electron transfer by Synechocystis sp. PCC6803. PLoS One 2014; 9:e91484. [PMID: 24637387 PMCID: PMC3956611 DOI: 10.1371/journal.pone.0091484] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 02/11/2014] [Indexed: 12/03/2022] Open
Abstract
Biophotovoltaic devices employ photosynthetic organisms at the anode of a microbial fuel cell to generate electrical power. Although a range of cyanobacteria and algae have been shown to generate photocurrent in devices of a multitude of architectures, mechanistic understanding of extracellular electron transfer by phototrophs remains minimal. Here we describe a mediatorless bioelectrochemical device to measure the electrogenic output of a planktonically grown cyanobacterium, Synechocystis sp. PCC6803. Light dependent production of current is measured, and its magnitude is shown to scale with microbial cell concentration and light intensity. Bioelectrochemical characterization of a Synechocystis mutant lacking Photosystem II demonstrates conclusively that production of the majority of photocurrent requires a functional water splitting aparatus and electrons are likely ultimately derived from water. This shows the potential of the device to rapidly and quantitatively characterize photocurrent production by genetically modified strains, an approach that can be used in future studies to delineate the mechanisms of cyanobacterial extracellular electron transport.
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Affiliation(s)
- Angelo Cereda
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona, United States of America
| | - Andrew Hitchcock
- Ocean and Earth Sciences, University of Southampton, Southampton, United Kingdom
| | - Mark D. Symes
- School of Chemistry, The University of Glasgow, Glasgow, United Kingdom
| | - Leroy Cronin
- School of Chemistry, The University of Glasgow, Glasgow, United Kingdom
| | - Thomas S. Bibby
- Ocean and Earth Sciences, University of Southampton, Southampton, United Kingdom
| | - Anne K. Jones
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona, United States of America
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