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Rasul F, You D, Jiang Y, Liu X, Daroch M. Thermophilic cyanobacteria-exciting, yet challenging biotechnological chassis. Appl Microbiol Biotechnol 2024; 108:270. [PMID: 38512481 PMCID: PMC10957709 DOI: 10.1007/s00253-024-13082-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/16/2024] [Accepted: 02/19/2024] [Indexed: 03/23/2024]
Abstract
Thermophilic cyanobacteria are prokaryotic photoautotrophic microorganisms capable of growth between 45 and 73 °C. They are typically found in hot springs where they serve as essential primary producers. Several key features make these robust photosynthetic microbes biotechnologically relevant. These are highly stable proteins and their complexes, the ability to actively transport and concentrate inorganic carbon and other nutrients, to serve as gene donors, microbial cell factories, and sources of bioactive metabolites. A thorough investigation of the recent progress in thermophilic cyanobacteria reveals a significant increase in the number of newly isolated and delineated organisms and wide application of thermophilic light-harvesting components in biohybrid devices. Yet despite these achievements, there are still deficiencies at the high-end of the biotechnological learning curve, notably in genetic engineering and gene editing. Thermostable proteins could be more widely employed, and an extensive pool of newly available genetic data could be better utilised. In this manuscript, we attempt to showcase the most important recent advances in thermophilic cyanobacterial biotechnology and provide an overview of the future direction of the field and challenges that need to be overcome before thermophilic cyanobacterial biotechnology can bridge the gap with highly advanced biotechnology of their mesophilic counterparts. KEY POINTS: • Increased interest in all aspects of thermophilic cyanobacteria in recent years • Light harvesting components remain the most biotechnologically relevant • Lack of reliable molecular biology tools hinders further development of the chassis.
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Affiliation(s)
- Faiz Rasul
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Dawei You
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Ying Jiang
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Xiangjian Liu
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Maurycy Daroch
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China.
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2
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Krysiak S, Gotić M, Madej E, Moreno Maldonado AC, Goya GF, Spiridis N, Burda K. The effect of ultrafine WO 3 nanoparticles on the organization of thylakoids enriched in photosystem II and energy transfer in photosystem II complexes. Microsc Res Tech 2023; 86:1583-1598. [PMID: 37534550 DOI: 10.1002/jemt.24394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/20/2023] [Accepted: 07/21/2023] [Indexed: 08/04/2023]
Abstract
In this work, a new approach to construct self-assembled hybrid systems based on natural PSII-enriched thylakoid membranes (PSII BBY) is demonstrated. Superfine m-WO3 NPs (≈1-2 nm) are introduced into PSII BBY. Transmission electron microscopy (TEM) measurements showed that even the highest concentrations of NPs used did not degrade the PSII BBY membranes. Using atomic force microscopy (AFM), it is shown that the organization of PSII BBY depends strongly on the concentration of NPs applied. This proved that the superfine NPs can easily penetrate the thylakoid membrane and interact with its components. These changes are also related to the modified energy transfer between the external light-harvesting antennas and the PSII reaction center, shown by absorption and fluorescence experiments. The biohybrid system shows stability at pH 6.5, the native operating environment of PSII, so a high rate of O2 evolution is expected. In addition, the light-induced water-splitting process can be further stimulated by the direct interaction of superfine WO3 NPs with the donor and acceptor sides of PSII. The water-splitting activity and stability of this colloidal system are under investigation. RESEARCH HIGHLIGHTS: The phenomenon of the self-organization of a biohybrid system composed of thylakoid membranes enriched in photosystem II and superfine WO3 nanoparticles is studied using AFM and TEM. A strong dependence of the organization of PSII complexes within PSII BBY membranes on the concentration of NPs applied is observed. This observation turns out to be crucial to understand the complexity of the mechanism of the action of WO3 NPs on modifications of energy transfer from external antenna complexes to the PSII reaction center.
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Affiliation(s)
- S Krysiak
- Faculty of Physics and Applied Computer Science, AGH - University of Krakow, Krakow, Poland
| | - M Gotić
- Division of Materials Physics, Ruđer Bošković Institute, Zagreb, Croatia
| | - E Madej
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Krakow, Poland
| | - A C Moreno Maldonado
- Condensed Matter Physics Department and Instituto de Nanociencia y Materiales de Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - G F Goya
- Condensed Matter Physics Department and Instituto de Nanociencia y Materiales de Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - N Spiridis
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Krakow, Poland
| | - K Burda
- Faculty of Physics and Applied Computer Science, AGH - University of Krakow, Krakow, Poland
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3
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Machín A, Cotto M, Ducongé J, Márquez F. Artificial Photosynthesis: Current Advancements and Future Prospects. Biomimetics (Basel) 2023; 8:298. [PMID: 37504186 PMCID: PMC10807655 DOI: 10.3390/biomimetics8030298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/01/2023] [Accepted: 07/07/2023] [Indexed: 07/29/2023] Open
Abstract
Artificial photosynthesis is a technology with immense potential that aims to emulate the natural photosynthetic process. The process of natural photosynthesis involves the conversion of solar energy into chemical energy, which is stored in organic compounds. Catalysis is an essential aspect of artificial photosynthesis, as it facilitates the reactions that convert solar energy into chemical energy. In this review, we aim to provide an extensive overview of recent developments in the field of artificial photosynthesis by catalysis. We will discuss the various catalyst types used in artificial photosynthesis, including homogeneous catalysts, heterogeneous catalysts, and biocatalysts. Additionally, we will explore the different strategies employed to enhance the efficiency and selectivity of catalytic reactions, such as the utilization of nanomaterials, photoelectrochemical cells, and molecular engineering. Lastly, we will examine the challenges and opportunities of this technology as well as its potential applications in areas such as renewable energy, carbon capture and utilization, and sustainable agriculture. This review aims to provide a comprehensive and critical analysis of state-of-the-art methods in artificial photosynthesis by catalysis, as well as to identify key research directions for future advancements in this field.
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Affiliation(s)
- Abniel Machín
- Divisionof Natural Sciences and Technology, Universidad Ana G. Méndez-Cupey Campus, San Juan, PR 00926, USA
| | - María Cotto
- Nanomaterials Research Group, Department of Natural Sciences and Technology, Universidad Ana G. Méndez-Gurabo Campus, Gurabo, PR 00778, USA; (M.C.); (J.D.)
| | - José Ducongé
- Nanomaterials Research Group, Department of Natural Sciences and Technology, Universidad Ana G. Méndez-Gurabo Campus, Gurabo, PR 00778, USA; (M.C.); (J.D.)
| | - Francisco Márquez
- Nanomaterials Research Group, Department of Natural Sciences and Technology, Universidad Ana G. Méndez-Gurabo Campus, Gurabo, PR 00778, USA; (M.C.); (J.D.)
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Morlock S, Subramanian SK, Zouni A, Lisdat F. Closing the green gap of photosystem I with synthetic fluorophores for enhanced photocurrent generation in photobiocathodes. Chem Sci 2023; 14:1696-1708. [PMID: 36819875 PMCID: PMC9930989 DOI: 10.1039/d2sc05324a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 01/04/2023] [Indexed: 01/18/2023] Open
Abstract
One restriction for biohybrid photovoltaics is the limited conversion of green light by most natural photoactive components. The present study aims to fill the green gap of photosystem I (PSI) with covalently linked fluorophores, ATTO 590 and ATTO 532. Photobiocathodes are prepared by combining a 20 μm thick 3D indium tin oxide (ITO) structure with these constructs to enhance the photocurrent density compared to setups based on native PSI. To this end, two electron transfer mechanisms, with and without a mediator, are studied to evaluate differences in the behavior of the constructs. Wavelength-dependent measurements confirm the influence of the additional fluorophores on the photocurrent. The performance is significantly increased for all modifications compared to native PSI when cytochrome c is present as a redox-mediator. The photocurrent almost doubles from -32.5 to up to -60.9 μA cm-2. For mediator-less photobiocathodes, interestingly, drastic differences appear between the constructs made with various dyes. While the turnover frequency (TOF) is doubled to 10 e-/PSI/s for PSI-ATTO590 on the 3D ITO compared to the reference specimen, the photocurrents are slightly smaller since the PSI-ATTO590 coverage is low. In contrast, the PSI-ATTO532 construct performs exceptionally well. The TOF increases to 31 e-/PSI/s, and a photocurrent of -47.0 μA cm-2 is obtained. This current is a factor of 6 better than the reference made with native PSI in direct electron transfer mode and sets a new record for mediator-free photobioelectrodes combining 3D electrode structures and light-converting biocomponents.
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Affiliation(s)
- Sascha Morlock
- Biosystems Technology, Technical University of Applied Sciences Wildau Hochschulring 1 15745 Wildau Germany .,Biophysics of Photosynthesis, Humboldt University of Berlin Philippstraße 13 10099 Berlin Germany
| | - Senthil K. Subramanian
- Biophysics of Photosynthesis, Humboldt University of BerlinPhilippstraße 1310099 BerlinGermany
| | - Athina Zouni
- Biophysics of Photosynthesis, Humboldt University of BerlinPhilippstraße 1310099 BerlinGermany
| | - Fred Lisdat
- Biosystems Technology, Technical University of Applied Sciences Wildau Hochschulring 1 15745 Wildau Germany
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Morimoto A, Hosokawa Y, Miyamoto H, Verma RK, Iwai S, Sato R, Yamamoto J. Key interactions with deazariboflavin cofactor for light-driven energy transfer in Xenopus (6-4) photolyase. Photochem Photobiol Sci 2021; 20:875-887. [PMID: 34120300 DOI: 10.1007/s43630-021-00065-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 06/03/2021] [Indexed: 10/21/2022]
Abstract
Photolyases are flavoenzymes responsible for light-driven repair of carcinogenic crosslinks formed in DNA by UV exposure. They possess two non-covalently bound chromophores: flavin adenine dinucleotide (FAD) as a catalytic center and an auxiliary antenna chromophore that harvests photons and transfers solar energy to the catalytic center. Although the energy transfer reaction has been characterized by time-resolved spectroscopy, it is strikingly important to understand how well natural biological systems organize the chromophores for the efficient energy transfer. Here, we comprehensively characterized the binding of 8-hydroxy-7,8-didemethyl-5-deazariboflavin (8-HDF) to Xenopus (6-4) photolyase. In silico simulations indicated that a hydrophobic amino acid residue located at the entrance of the binding site dominates translocation of a loop upon binding of 8-HDF, and a mutation of this residue caused dysfunction of the efficient energy transfer in the DNA repair reaction. Mutational analyses of the protein combined with modification of the chromophore suggested that Coulombic interactions between positively charged residues in the protein and the phenoxide moiety in 8-HDF play a key role in accommodation of 8-HDF in the proper direction. This study provides a clear evidence that Xenopus (6-4) photolyase can utilize 8-HDF as the light-harvesting chromophore. The obtained new insights into binding of the natural antenna molecule will be helpful for the development of artificial light-harvesting chromophores and future characterization of the energy transfer in (6-4) photolyase by spectroscopic studies.
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Affiliation(s)
- Ayaka Morimoto
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Yuhei Hosokawa
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Hiromu Miyamoto
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Rajiv Kumar Verma
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan.,Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Shigenori Iwai
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Ryuma Sato
- Center for Biosystems Dynamics Research, RIKEN, 6-2-3 Furuedai, Suita, Osaka, 565-0874, Japan.,Cellular and Molecular Biotechnology Research and Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-3-26 Aomi, Koto-ku, Tokyo, 135-0064, Japan
| | - Junpei Yamamoto
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan.
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Teodor AH, Ooi EJ, Medina J, Alarcon M, Vaughn MD, Bruce BD, Bergkamp JJ. Aqueous-soluble bipyridine cobalt(ii/iii) complexes act as direct redox mediators in photosystem I-based biophotovoltaic devices. RSC Adv 2021; 11:10434-10450. [PMID: 35423559 PMCID: PMC8695705 DOI: 10.1039/d0ra10221k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 02/28/2021] [Indexed: 01/13/2023] Open
Abstract
Sustainable energy production is critical for meeting growing worldwide energy demands. Due to its stability and reduction potential, photosystem I (PSI) is attractive as the photosensitizer in biophotovoltaic devices. Herein, we characterize aqueous and organic solvent soluble synthetic bipyridine-based cobalt complexes as redox mediators for PSI-based biophotovoltaics applications. Cobalt-based complexes are not destructive to protein and have appropriate midpoint potentials for electron donation to PSI. We report on PSI stability in organic solvents commonly used in biophotovoltaics. We also show the effects of a mixed organic solvent phase on PSI reduction kinetics, slowing reduction rates approximately 8–38 fold as compared to fully aqueous systems, with implications for dye regeneration rates in PSI-based biophotovoltaics. Further, we show evidence of direct electron transfer from cobalt complexes to PSI. Finally, we report on photocurrent generation from Co mediator-PSI biophotovoltaic devices. Taken together, we discuss the development of novel Co complexes and our ability to fine-tune their characteristics via functional groups and counteranion choice to drive interaction with a biological electron acceptor on multiple levels from redox midpoints, spectral overlap, and solvent requirements, among others. This work suggests that fine-tuning of redox active species for interaction with a biological partner is possible for the creation and improvement of low cost, carbon-neutral energy production in the future. Sustainable energy production is critical for meeting growing worldwide energy demands.![]()
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Affiliation(s)
- Alexandra H Teodor
- Graduate School of Genome Science and Technology, University of Tennessee at Knoxville and Oak Ridge National Laboratory USA
| | - Eu-Jee Ooi
- Department of Chemistry and Biochemistry, California State University Bakersfield USA
| | - Jackeline Medina
- Department of Chemistry and Biochemistry, California State University Bakersfield USA
| | - Miguel Alarcon
- Department of Chemistry and Biochemistry, California State University Bakersfield USA
| | | | - Barry D Bruce
- Graduate School of Genome Science and Technology, University of Tennessee at Knoxville and Oak Ridge National Laboratory USA .,Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee at Knoxville USA.,Department of Chemical and Biomolecular Engineering, University of Tennessee at Knoxville USA
| | - Jesse J Bergkamp
- Department of Chemistry and Biochemistry, California State University Bakersfield USA
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Abstract
The biological process of photosynthesis was critical in catalyzing the oxygenation of Earth’s atmosphere 2.5 billion years ago, changing the course of development of life on Earth. Recently, the fields of applied and synthetic photosynthesis have utilized the light-driven protein–pigment supercomplexes central to photosynthesis for the photocatalytic production of fuel and other various valuable products. The reaction center Photosystem I is of particular interest in applied photosynthesis due to its high stability post-purification, non-geopolitical limitation, and its ability to generate the greatest reducing power found in nature. These remarkable properties have been harnessed for the photocatalytic production of a number of valuable products in the applied photosynthesis research field. These primarily include photocurrents and molecular hydrogen as fuels. The use of artificial reaction centers to generate substrates and reducing equivalents to drive non-photoactive enzymes for valuable product generation has been a long-standing area of interest in the synthetic photosynthesis research field. In this review, we cover advances in these areas and further speculate synthetic and applied photosynthesis as photocatalysts for the generation of valuable products.
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Abstract
Meeting growing energy demands sustainably is one of the greatest challenges facing the world. The sun strikes the Earth with sufficient energy in 1.5 h to meet annual world energy demands, likely making solar energy conversion part of future sustainable energy production plans. Photosynthetic organisms have been evolving solar energy utilization strategies for nearly 3.5 billion years, making reaction centers including the remarkably stable Photosystem I (PSI) especially interesting for biophotovoltaic device integration. Although these biohybrid devices have steadily improved, their output remains low compared with traditional photovoltaics. We discuss strategies and methods to improve PSI-based biophotovoltaics, focusing on PSI-surface interaction enhancement, electrolytes, and light-harvesting enhancement capabilities. Desirable features and current drawbacks to PSI-based devices are also discussed.
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Affiliation(s)
- Alexandra H Teodor
- Graduate School of Genome Science and Technology, University of Tennessee at Knoxville, Knoxville, TN 37996, USA; Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - Barry D Bruce
- Graduate School of Genome Science and Technology, University of Tennessee at Knoxville, Knoxville, TN 37996, USA; Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA; Department of Biochemistry, Cellular, and Molecular Biology, University of Tennessee at Knoxville, Knoxville, TN 37996, USA; Department of Chemical and Biomolecular Engineering, University of Tennessee at Knoxville, Knoxville, TN 37996, USA.
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9
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Abstract
Many strategies for meeting mankind's future energy demands through the exploitation of plentiful solar energy have been influenced by the efficient and sustainable processes of natural photosynthesis. A limitation affecting solar energy conversion based on photosynthetic proteins is the selective spectral coverage that is the consequence of their particular natural pigmentation. Here we demonstrate the bottom-up formation of semisynthetic, polychromatic photosystems in mixtures of the chlorophyll-based LHCII major light harvesting complex from the oxygenic green plant Arabidopsis thaliana, the bacteriochlorophyll-based photochemical reaction center (RC) from the anoxygenic purple bacterium Rhodobacter sphaeroides and synthetic quantum dots (QDs). Polyhistidine tag adaptation of LHCII and the RC enabled predictable self-assembly of LHCII/RC/QD nanoconjugates, the thermodynamics of which could be accurately modeled and parametrized. The tricomponent biohybrid photosystems displayed enhanced solar energy conversion via either direct chlorophyll-to-bacteriochlorophyll energy transfer or an indirect pathway enabled by the QD, with an overall energy transfer efficiency comparable to that seen in natural photosystems.
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Affiliation(s)
- Juntai Liu
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
| | - Judith Mantell
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
- Wolfson Bioimaging Facility, Biomedical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
| | - Michael R Jones
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
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Affiliation(s)
- P. Sampath
- Dayananda Sagar College of EngineeringDepartment of Chemical Engineering 560078 Bengaluru Karnataka India
| | - Brijesh
- Ramaiah Institute of TechnologyDepartment of Chemical Engineering 560054 Bengaluru Karnataka India
| | - Kakarla Raghava Reddy
- The University of SydneySchool of Chemical and Biomolecular Engineering NSW 2006 Sydney Australia
| | - C. Venkata Reddy
- Yeungnam UniversitySchool of Mechanical Engineering 712-749 Gyeongsan South Korea
| | - Nagaraj P. Shetti
- K.L.E Institute of TechnologyDepartment of Chemistry 580030 Gokul, Hubballi Karnataka India
| | - Raghavendra V. Kulkarni
- BLDEA's SSM College of Pharmacy and Research CentreDepartment of Pharmaceutics 586 103 Karnataka Vijayapur India
| | - Anjanapura V. Raghu
- JAIN Deemed-to-be UniversityDepartment of Basic SciencesCenter for Emerging Technology (CET)School of Chemistry 562112 Karnataka Bangalore India
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Gorka M, Golbeck JH. Generating dihydrogen by tethering an [FeFe]hydrogenase via a molecular wire to the A 1A/A 1B sites of photosystem I. Photosynth Res 2020; 143:155-163. [PMID: 31673863 DOI: 10.1007/s11120-019-00685-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 10/15/2019] [Indexed: 06/10/2023]
Abstract
Photosystem I complexes from the menB deletion mutant of Synechocystis sp. PCC 6803 were previously wired to a Pt nanoparticle via a molecular wire consisting of 15-(3-methyl-1,4-naphthoquinone-2-yl)]pentadecyl sulfide. In the presence of a sacrificial electron donor and an electron transport mediator, the PS I-NQ(CH2)15S-Pt nanoconstruct generated dihydrogen at a rate of 44.3 µmol of H2 mg Chl-1 h-1 during illumination at pH 8.3. The menB deletion strain contains an interruption in the biosynthetic pathway of phylloquinone, which results in the presence of a displaceable plastoquinone-9 in the A1A/A1B sites. The synthesized quinone contains a headgroup identical to the native phylloquinone along with a 15-carbon long tail that is terminated in a thiol. The thiol on the molecular wire is used to bind the Pt nanoparticle. In this short communication, we replaced the Pt nanoparticle with an [FeFe]H2ase variant from Clostridium acetobutylicum that contains an exposed iron on the distal [4Fe-4S] cluster afforded by mutating the surface exposed Cys97 residue to Gly. The thiol on the molecular wire is then used to coordinate the corner iron atom of the iron-sulfur cluster. When all three components are combined and illuminated in the presence of a sacrificial electron donor and an electron transport mediator, the PS I-NQ(CH2)15S-[FeFe]H2ase nanoconstruct generated dihydrogen at a rate of 50.3 ± 9.96 μmol of H2 mg Chl-1 h-1 during illumination at pH 8.3. This successful in vitro experiment sets the stage for assembling a PS I-NQ(CH2)15S-[FeFe]H2ase nanoconstruct in vivo in the menB mutant of Synechocystis sp. PCC 6803.
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Affiliation(s)
- Michael Gorka
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S328 Frear Building, University Park, PA, 16802, USA.
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