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Wang Y, Wang Y, Zhou K, Zhang H, Cheng M, Wang B, Yan X. Isolation of a facultative methanotroph Methylocystis iwaonis SD4 from rice rhizosphere and establishment of rapid genetic tools for it. Biotechnol Lett 2024; 46:713-724. [PMID: 38733438 DOI: 10.1007/s10529-024-03495-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 04/10/2024] [Accepted: 04/21/2024] [Indexed: 05/13/2024]
Abstract
Methanotrophs of the genus Methylocystis are frequently found in rice paddies. Although more than ten facultative methanotrophs have been reported since 2005, none of these strains was isolated from paddy soil. Here, a facultative methane-oxidizing bacterium, Methylocystis iwaonis SD4, was isolated and characterized from rhizosphere samples of rice plants in Nanjing, China. This strain grew well on methane or methanol but was able to grow slowly using acetate or ethanol. Moreover, strain SD4 showed sustained growth at low concentrations of methane (100 and 500 ppmv). M. iwaonis SD4 could utilize diverse nitrogen sources, including nitrate, urea, ammonium as well as dinitrogen. Strain SD4 possessed genes encoding both the particulate methane monooxygenase and the soluble methane monooxygenase. Simple and rapid genetic manipulation methods were established for this strain, enabling vector transformation and unmarked genetic manipulation. Fast growth rate and efficient genetic tools make M. iwaonis SD4 an ideal model to study facultative methanotrophs, and the ability to grow on low concentration of methane implies its potential in methane removal.
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Affiliation(s)
- Yinghui Wang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Yuying Wang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Keyu Zhou
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Haili Zhang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Minggen Cheng
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Baozhan Wang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Xin Yan
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, People's Republic of China.
- Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Key Lab of Organic-Based Fertilizers of China, Jiangsu Collaborative Innovation Center for Solid Organic Wastes, Educational Ministry Engineering Center of Resource-Saving Fertilizers, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
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Christi K, Hudson J, Egan S. Current approaches to genetic modification of marine bacteria and considerations for improved transformation efficiency. Microbiol Res 2024; 284:127729. [PMID: 38663232 DOI: 10.1016/j.micres.2024.127729] [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: 10/18/2023] [Revised: 02/25/2024] [Accepted: 04/15/2024] [Indexed: 05/26/2024]
Abstract
Marine bacteria play vital roles in symbiosis, biogeochemical cycles and produce novel bioactive compounds and enzymes of interest for the pharmaceutical, biofuel and biotechnology industries. At present, investigations into marine bacterial functions and their products are primarily based on phenotypic observations, -omic type approaches and heterologous gene expression. To advance our understanding of marine bacteria and harness their full potential for industry application, it is critical that we have the appropriate tools and resources to genetically manipulate them in situ. However, current genetic tools that are largely designed for model organisms such as E. coli, produce low transformation efficiencies or have no transfer ability in marine bacteria. To improve genetic manipulation applications for marine bacteria, we need to improve transformation methods such as conjugation and electroporation in addition to identifying more marine broad host range plasmids. In this review, we aim to outline the reported methods of transformation for marine bacteria and discuss the considerations for each approach in the context of improving efficiency. In addition, we further discuss marine plasmids and future research areas including CRISPR tools and their potential applications for marine bacteria.
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Affiliation(s)
- Katrina Christi
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, Faculty of Science, The University of New South Wales, Kensington, NSW, Australia
| | - Jennifer Hudson
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, Faculty of Science, The University of New South Wales, Kensington, NSW, Australia
| | - Suhelen Egan
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, Faculty of Science, The University of New South Wales, Kensington, NSW, Australia.
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Jiang J, Zhao Y, Chen A, Sun J, Zhou M, Hu J, Cao X, Dai N, Liang Z, Feng S. Efficient markerless genetic manipulation of Pasteurella multocida using lacZ and pheSm as selection markers. Appl Environ Microbiol 2024; 90:e0204323. [PMID: 38547470 PMCID: PMC11022533 DOI: 10.1128/aem.02043-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 03/07/2024] [Indexed: 04/18/2024] Open
Abstract
Pasteurella multocida is a zoonotic conditional pathogen that infects multiple livestock species, causing substantial economic losses in the animal husbandry industry. An efficient markerless method for gene manipulation may facilitate the investigations of P. multocida gene function and pathogenesis of P. multocida. Herein, a temperature-sensitive shuttle vector was constructed using lacZ as a selection marker, and markerless glgB, opa, and hyaE mutants of P. multocida were subsequently constructed through blue-white colony screening. The screening efficiency of markerless deletion strains was improved by the lacZ system, and the method could be used for multiple gene deletions. However, the fur mutant was unavailable via this method. Therefore, we constructed a pheSm screening system based on mutated phenylalanine tRNA synthetase as a counterselection marker to achieve fur deletion mutant. The transformed strain was sensitive to 20 mM p-chloro-phenylalanine, demonstrating the feasibility of pheSm as a counter-selective marker. The pheSm system was used for markerless deletions of glgB, opa, and hyaE as well as fur that could not be screened by the lacZ system. A comparison of screening efficiencies of the system showed that the pheSm counterselection system was more efficient than the lacZ system and broadly applicable for mutant screening. The methods developed herein may provide valuable tools for genetic manipulation of P. multocida.IMPORTANCEPasteurella multocida is a highly contagious zoonotic pathogen. An understanding of its underlying pathogenic mechanisms is of considerable importance and requires efficient species-specific genetic tools. Herein, we propose a screening system for P. multocida mutants using lacZ or pheSm screening markers. We evaluated the efficiencies of both systems, which were used to achieve markerless deletion of multiple genes. The results of this study support the use of lacZ or pheSm as counterselection markers to improve counterselection efficiency in P. multocida. This study provides an effective genetic tool for investigations of the virulence gene functions and pathogenic mechanisms of P. multocida.
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Affiliation(s)
- Jinfei Jiang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Yishan Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Aihua Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Juan Sun
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Mengruo Zhou
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Jialian Hu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Xuewei Cao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Ning Dai
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Zhaoping Liang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou, China
- Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, Guangzhou, China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture and Rural Affairs, Guangzhou, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou, China
| | - Saixiang Feng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou, China
- Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, Guangzhou, China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture and Rural Affairs, Guangzhou, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou, China
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Bedekar AA, Deewan A, Jagtap SS, Parker DA, Liu P, Mackie RI, Rao CV. Transcriptional and metabolomic responses of Methylococcus capsulatus Bath to nitrogen source and temperature downshift. Front Microbiol 2023; 14:1259015. [PMID: 37928661 PMCID: PMC10623323 DOI: 10.3389/fmicb.2023.1259015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/10/2023] [Indexed: 11/07/2023] Open
Abstract
Methanotrophs play a significant role in methane oxidation, because they are the only biological methane sink present in nature. The methane monooxygenase enzyme oxidizes methane or ammonia into methanol or hydroxylamine, respectively. While much is known about central carbon metabolism in methanotrophs, far less is known about nitrogen metabolism. In this study, we investigated how Methylococcus capsulatus Bath, a methane-oxidizing bacterium, responds to nitrogen source and temperature. Batch culture experiments were conducted using nitrate or ammonium as nitrogen sources at both 37°C and 42°C. While growth rates with nitrate and ammonium were comparable at 42°C, a significant growth advantage was observed with ammonium at 37°C. Utilization of nitrate was higher at 42°C than at 37°C, especially in the first 24 h. Use of ammonium remained constant between 42°C and 37°C; however, nitrite buildup and conversion to ammonia were found to be temperature-dependent processes. We performed RNA-seq to understand the underlying molecular mechanisms, and the results revealed complex transcriptional changes in response to varying conditions. Different gene expression patterns connected to respiration, nitrate and ammonia metabolism, methane oxidation, and amino acid biosynthesis were identified using gene ontology analysis. Notably, key pathways with variable expression profiles included oxidative phosphorylation and methane and methanol oxidation. Additionally, there were transcription levels that varied for genes related to nitrogen metabolism, particularly for ammonia oxidation, nitrate reduction, and transporters. Quantitative PCR was used to validate these transcriptional changes. Analyses of intracellular metabolites revealed changes in fatty acids, amino acids, central carbon intermediates, and nitrogen bases in response to various nitrogen sources and temperatures. Overall, our results offer improved understanding of the intricate interactions between nitrogen availability, temperature, and gene expression in M. capsulatus Bath. This study enhances our understanding of microbial adaptation strategies, offering potential applications in biotechnological and environmental contexts.
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Affiliation(s)
- Ashwini Ashok Bedekar
- Energy and Biosciences Institute, Materials Research Laboratory, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Anshu Deewan
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Sujit S. Jagtap
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - David A. Parker
- Energy and Biosciences Institute, Materials Research Laboratory, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Shell Exploration and Production Inc., Westhollow Technology Center, Houston, TX, United States
| | - Ping Liu
- Energy and Biosciences Institute, Materials Research Laboratory, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Shell Exploration and Production Inc., Westhollow Technology Center, Houston, TX, United States
| | - Roderick I. Mackie
- Energy and Biosciences Institute, Materials Research Laboratory, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Christopher V. Rao
- Energy and Biosciences Institute, Materials Research Laboratory, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, IL, United States
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Zheng Y, Fu H, Chen J, Li J, Bian Y, Hu P, Lei L, Liu Y, Yang J, Peng W. Development of a counterselectable system for rapid and efficient CRISPR-based genome engineering in Zymomonas mobilis. Microb Cell Fact 2023; 22:208. [PMID: 37833755 PMCID: PMC10571335 DOI: 10.1186/s12934-023-02217-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
BACKGROUND Zymomonas mobilis is an important industrial bacterium ideal for biorefinery and synthetic biology studies. High-throughput CRISPR-based genome editing technologies have been developed to enable targeted engineering of genes and hence metabolic pathways in the model ZM4 strain, expediting the exploitation of this biofuel-producing strain as a cell factory for sustainable chemicals, proteins and biofuels production. As these technologies mainly take plasmid-based strategies, their applications would be impeded due to the fact that curing of the extremely stable plasmids is laborious and inefficient. Whilst counterselection markers have been proven to be efficient for plasmid curing, hitherto only very few counterselection markers have been available for Z. mobilis. RESULTS We constructed a conditional lethal mutant of the pheS gene of Z. mobilis ZM4, clmPheS, containing T263A and A318G substitutions and coding for a mutated alpha-subunit of phenylalanyl-tRNA synthetase to allow for the incorporation of a toxic analog of phenylalanine, p-chloro-phenylalanine (4-CP), into proteins, and hence leading to inhibition of cell growth. We demonstrated that expression of clmPheS driven by a strong Pgap promoter from a plasmid could render the Z. mobilis ZM4 cells sufficient sensitivity to 4-CP. The clmPheS-expressing cells were assayed to be extremely sensitive to 0.2 mM 4-CP. Subsequently, the clmPheS-assisted counterselection endowed fast curing of genome engineering plasmids immediately after obtaining the desired mutants, shortening the time of every two rounds of multiplex chromosome editing by at least 9 days, and enabled the development of a strategy for scarless modification of the native Z. mobilis ZM4 plasmids. CONCLUSIONS This study developed a strategy, coupling an endogenous CRISPR-based genome editing toolkit with a counterselection marker created here, for rapid and efficient multi-round multiplex editing of the chromosome, as well as scarless modification of the native plasmids, providing an improved genome engineering toolkit for Z. mobilis and an important reference to develope similar genetic manipulation systems in other non-model organisms.
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Affiliation(s)
- Yanli Zheng
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430023, P. R. China
| | - Hongmei Fu
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430023, P. R. China
| | - Jue Chen
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430023, P. R. China
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, The College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, P. R. China
| | - Jie Li
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, The College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, P. R. China
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, 430062, P.R. China
| | - Yuejie Bian
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, 430062, P.R. China
| | - Ping Hu
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430023, P. R. China
| | - Lei Lei
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430023, P. R. China
| | - Yihan Liu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, The College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, P. R. China.
| | - Jiangke Yang
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430023, P. R. China.
| | - Wenfang Peng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Engineering Research Center for Bio-enzyme Catalysis, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, 430062, P.R. China.
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Rumah B, Claxton Stevens BH, Yeboah JE, Stead CE, Harding EL, Minton NP, Zhang Y. In Vivo Genome Editing in Type I and II Methanotrophs Using a CRISPR/Cas9 System. ACS Synth Biol 2023; 12:544-554. [PMID: 36688528 PMCID: PMC9942187 DOI: 10.1021/acssynbio.2c00554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Methanotrophic bacteria are Gram-negative, aerobic organisms that use methane as their sole source of carbon and energy. In this study, we constructed and exemplified a CRISPR/Cas9 genome editing system and used it to successfully make gene deletions and insertions in the type I methanotroph Methylococcus capsulatus Bath and the type II methanotroph Methylocystis parvus OBBP. High frequencies of gene deletions and insertions were achieved in combination with homology-directed repair. In M. parvus OBBP, we also investigated the impact of several parameters on the CRISPR/Cas9 genome editing, where the ligD gene was targeted with various PAM sequences and guide RNA spacer sequences, homology arms of variable length, differences in the duration of mating during conjugation, and exploiting promoters of different strengths to control the expression of cas9 and sgRNA. Although not the first attempt to develop a CRISPR/Cas system in methanotrophs, this work demonstrated for the first time an efficient CRISPR/Cas9 system generating scarless clean gene deletions and insertions in methanotroph genomes.
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Khmelenina VN, But SY, Rozova ON, Oshkin IY, Pimenov NV, Dedysh SN. Genome Editing in Methanotrophic Bacteria: Potential Targets and Available Tools. Microbiology (Reading) 2022. [DOI: 10.1134/s0026261722602196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Abstract
Microbes with the capacity to use methane (CH4) as a carbon source (methanotrophs) have significant potential for the bioconversion of CH4-containing natural gas and anaerobic digestion-derived biogas to high value products. These organisms also play a vital role in the biogeochemical cycling of atmospheric CH4 by serving as the only known biological sink of this gas in terrestrial and aquatic ecosystems. Much is known regarding the enzymes and central metabolic pathways mediating CH4 utilization in these bacteria. However, large fundamental knowledge gaps exist regarding methanotroph physiology and responses to environmental stimuli, primarily due to a lack of efficient molecular tools to probe gene-function relationships. In this chapter, we describe several recently developed genetic tools and optimized genome editing methods that can be used for methanotroph metabolic engineering and to probe metabolic and physiological governing mechanisms in these unique bacteria.
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Affiliation(s)
- Sreemoye Nath
- Department of Biological Sciences, University of North Texas, Denton, TX, USA
- BioDiscovery Institute, University of North Texas, Denton, TX, USA
| | - Jessica M Henard
- BioDiscovery Institute, University of North Texas, Denton, TX, USA
| | - Calvin A Henard
- Department of Biological Sciences, University of North Texas, Denton, TX, USA.
- BioDiscovery Institute, University of North Texas, Denton, TX, USA.
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Plasmid Curing and Exchange Using a Novel Counter-Selectable Marker Based on Unnatural Amino Acid Incorporation at a Sense Codon. Int J Mol Sci 2021; 22:ijms222111482. [PMID: 34768910 PMCID: PMC8583848 DOI: 10.3390/ijms222111482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 11/25/2022] Open
Abstract
A protocol was designed for plasmid curing using a novel counter-selectable marker, named pylSZK-pylT, in Escherichia coli. The pylSZK-pylT marker consists of the archaeal pyrrolysyl-tRNA synthetase (PylRS) and its cognate tRNA (tRNApyl) with modification, and incorporates an unnatural amino acid (Uaa), Nε-benzyloxycarbonyl-l-lysine (ZK), at a sense codon in ribosomally synthesized proteins, resulting in bacterial growth inhibition or killing. Plasmid curing is performed by exerting toxicity on pylSZK-pylT located on the target plasmid, and selecting only proliferative bacteria. All tested bacteria obtained using this protocol had lost the target plasmid (64/64), suggesting that plasmid curing was successful. Next, we attempted to exchange plasmids with the identical replication origin and an antibiotic resistance gene without plasmid curing using a modified protocol, assuming substitution of plasmids complementing genomic essential genes. All randomly selected bacteria after screening had only the substitute plasmid and no target plasmid (25/25), suggesting that plasmid exchange was also accomplished. Counter-selectable markers based on PylRS-tRNApyl, such as pylSZK-pylT, may be scalable in application due to their independence from the host genotype, applicability to a wide range of species, and high tunability due to the freedom of choice of target codons and Uaa’s to be incorporated.
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Lee H, Baek JI, Lee JY, Jeong J, Kim H, Lee DH, Kim DM, Lee SG. Syntrophic co-culture of a methanotroph and heterotroph for the efficient conversion of methane to mevalonate. Metab Eng 2021; 67:285-292. [PMID: 34298134 DOI: 10.1016/j.ymben.2021.07.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/07/2021] [Accepted: 07/18/2021] [Indexed: 10/20/2022]
Abstract
As the bioconversion of methane becomes increasingly important for bio-industrial and environmental applications, methanotrophs have received much attention for their ability to convert methane under ambient conditions. This includes the extensive reporting of methanotroph engineering for the conversion of methane to biochemicals. To further increase methane usability, we demonstrated a highly flexible and efficient modular approach based on a synthetic consortium of methanotrophs and heterotrophs mimicking the natural methane ecosystem to produce mevalonate (MVA) from methane. In the methane-conversion module, we used Methylococcus capsulatus Bath as a highly efficient methane biocatalyst and optimized the culture conditions for the production of high amounts of organic acids. In the MVA-synthesis module, we used Escherichia coli SBA01, an evolved strain with high organic acid tolerance and utilization ability, to convert organic acids to MVA. Using recombinant E. coli SBA01 possessing genes for the MVA pathway, 61 mg/L (0.4 mM) of MVA was successfully produced in 48 h without any addition of nutrients except methane. Our platform exhibited high stability and reproducibility with regard to cell growth and MVA production. We believe that this versatile system can be easily extended to many other value-added processes and has a variety of potential applications.
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Affiliation(s)
- Hyewon Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Ji In Baek
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea; Department of Chemical Engineering and Applied Chemistry, Chungnam National University, 99 Daehak-ro, 34134, Republic of Korea
| | - Jin-Young Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Jiyeong Jeong
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Haseong Kim
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Dae-Hee Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea; Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science & Technology (UST), Daejeon, 34113, Republic of Korea
| | - Dong-Myung Kim
- Department of Chemical Engineering and Applied Chemistry, Chungnam National University, 99 Daehak-ro, 34134, Republic of Korea
| | - Seung-Goo Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea; Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science & Technology (UST), Daejeon, 34113, Republic of Korea.
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Liu Y, Zhang H, He X, Liu J. Genetically Engineered Methanotroph as a Platform for Bioaugmentation of Chemical Pesticide Contaminated Soil. ACS Synth Biol 2021; 10:487-494. [PMID: 33616380 DOI: 10.1021/acssynbio.0c00532] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bioaugmentation is a promising alternative in soil remediation. One challenge of bioaugmentation is that exogenous pollutant-degrading microbes added to soil cannot establish enough biomass to eliminate pollutants. Considering that methanotrophs have a growth advantage in the presence of methane, we hypothesize that genetically engineered methanotrophs could degrade contaminants efficiently in soil with methane. Here, methanotroph Methylomonas sp. LW13, herbicide bensulfuron-methyl (BSM), and two kinds of soil were chosen to confirm this hypothesis. The unmarked gene knock-in method was first developed for strain LW13. Then, BSM hydrolase encoding gene sulE was inserted into the chromosome of strain LW13, conferring it BSM-degrading ability. After inoculation, the cell amount of strain LW13-sulE in soil raised considerably (over 100 fold in 9 days) with methane provision; meanwhile, >90% of BSM in soil was degraded. This study provides a proof of the concept that genetically engineered methanotroph is a potential platform for soil remediation.
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Affiliation(s)
- Yongchuang Liu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Haili Zhang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Xiangrong He
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Juan Liu
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
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The Entner-Doudoroff Pathway Is an Essential Metabolic Route for Methylotuvimicrobium buryatense 5GB1C. Appl Environ Microbiol 2021; 87:AEM.02481-20. [PMID: 33218997 DOI: 10.1128/aem.02481-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 11/11/2020] [Indexed: 11/20/2022] Open
Abstract
Methylotuvimicrobium buryatense 5GB1C, a fast-growing gammaproteobacterial methanotroph, is equipped with two glycolytic pathways, the Entner-Doudoroff (ED) pathway and the Embden-Meyerhof-Parnas (EMP) pathway. Metabolic flux analysis and 13C-labeling experiments have shown the EMP pathway is the principal glycolytic route in M. buryatense 5GB1C, while the ED pathway appears to be metabolically and energetically insignificant. However, it has not been possible to obtain a null mutant in the edd-eda genes encoding the two unique enzymatic reactions in the ED pathway, suggesting the ED pathway may be essential for M. buryatense 5GB1C growth. In this study, the inducible P BAD promoter was used to manipulate gene expression of edd-eda, and in addition, the expression of these two genes was separated from that of a downstream gltA gene. The resulting strain shows arabinose-dependent growth that correlates with ED pathway activity, with normal growth achieved in the presence of ∼0.1 g/liter arabinose. Flux balance analysis shows that M. buryatense 5GB1C with a strong ED pathway has a reduced energy budget, thereby limiting the mutant growth at a high concentration of arabinose. Collectively, our study demonstrates that the ED pathway is essential for M. buryatense 5GB1C. However, no known mechanism can directly explain the essentiality of the ED pathway, and thus, it may have a yet unknown regulatory role required for sustaining a healthy and functional metabolism in this bacterium.IMPORTANCE The gammaproteobacterial methanotrophs possess a unique central metabolic architecture where methane and other reduced C1 carbon sources are assimilated through the ribulose monophosphate cycle. Although efforts have been made to better understand methanotrophic metabolism in these bacteria via experimental and computational approaches, many questions remain unanswered. One of these is the essentiality of the ED pathway for M. buryatense 5GB1C, as current results appear contradictory. By creating a construct with edd-eda and gltA genes controlled by P BAD and P J23101 , respectively, we demonstrated the essentiality of the ED pathway for this obligate methanotroph. It is also demonstrated that these genetic tools are applicable to M. buryatense 5GB1C and that expression of the target genes can be tightly controlled across an extensive range. Our study adds to the expanding knowledge of methanotrophic metabolism and practical approaches to genetic manipulation for obligate methanotrophs.
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Pastawan V, Suganuma S, Mizuno K, Wang L, Tani A, Mitsui R, Nakamura K, Shimada M, Hayakawa T, Fitriyanto NA, Nakagawa T. Regulation of lanthanide-dependent methanol oxidation pathway in the legume symbiotic nitrogen-fixing bacterium Bradyrhizobium sp. strain Ce-3. J Biosci Bioeng 2020; 130:582-587. [DOI: 10.1016/j.jbiosc.2020.07.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/12/2020] [Accepted: 07/15/2020] [Indexed: 02/06/2023]
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Nguyen AD, Lee EY. Engineered Methanotrophy: A Sustainable Solution for Methane-Based Industrial Biomanufacturing. Trends Biotechnol 2020; 39:381-396. [PMID: 32828555 DOI: 10.1016/j.tibtech.2020.07.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 07/16/2020] [Accepted: 07/17/2020] [Indexed: 12/22/2022]
Abstract
Methane is a promising feedstock with high abundance and low cost for the sustainable production of biochemicals and biofuels. Methanotrophic bacteria are particularly interesting platforms for methane bioconversion as they can utilize methane as a carbon substrate. Recently, breakthroughs in the understanding of methane metabolism in methanotrophs as well as critical advances in systems metabolic engineering of methanotrophic bacteria have been reported. Here, we discuss the important gaps in the understanding of methanotrophic metabolism that have been uncovered recently and the current trends in systems metabolic engineering in both methanotrophic bacteria and non-native hosts to advance the potential of methane-based biomanufacturing.
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Affiliation(s)
- Anh Duc Nguyen
- Department of Chemical Engineering, Kyung Hee University, Yongin-si, Gyeonggi-do 17104, South Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering, Kyung Hee University, Yongin-si, Gyeonggi-do 17104, South Korea.
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Cianfanelli FR, Cunrath O, Bumann D. Efficient dual-negative selection for bacterial genome editing. BMC Microbiol 2020; 20:129. [PMID: 32448155 PMCID: PMC7245781 DOI: 10.1186/s12866-020-01819-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 05/11/2020] [Indexed: 12/15/2022] Open
Abstract
Background Gene editing is key for elucidating gene function. Traditional methods, such as consecutive single-crossovers, have been widely used to modify bacterial genomes. However, cumbersome cloning and limited efficiency of negative selection often make this method slower than other methods such as recombineering. Results Here, we established a time-effective variant of consecutive single-crossovers. This method exploits rapid plasmid construction using Gibson assembly, a convenient E. coli donor strain, and efficient dual-negative selection for improved suicide vector resolution. We used this method to generate in-frame deletions, insertions and point mutations in Salmonella enterica with limited hands-on time. Adapted versions enabled efficient gene editing also in Pseudomonas aeruginosa and multi-drug resistant (MDR) Escherichia coli clinical isolates. Conclusions Our method is time-effective and allows facile manipulation of multiple bacterial species including MDR clinical isolates. We anticipate that this method might be broadly applicable to additional bacterial species, including those for which recombineering has been difficult to implement.
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Affiliation(s)
| | - Olivier Cunrath
- Biozentrum, University of Basel, CH-4056, Basel, Switzerland
| | - Dirk Bumann
- Biozentrum, University of Basel, CH-4056, Basel, Switzerland.
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Wang L, Hibino A, Suganuma S, Ebihara A, Iwamoto S, Mitsui R, Tani A, Shimada M, Hayakawa T, Nakagawa T. Preference for particular lanthanide species and thermal stability of XoxFs in Methylorubrum extorquens strain AM1. Enzyme Microb Technol 2020; 136:109518. [DOI: 10.1016/j.enzmictec.2020.109518] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/21/2020] [Accepted: 01/26/2020] [Indexed: 10/25/2022]
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Liu Y, He X, Zhu P, Cheng M, Hong Q, Yan X. pheS AG Based Rapid and Efficient Markerless Mutagenesis in Methylotuvimicrobium. Front Microbiol 2020; 11:441. [PMID: 32296398 PMCID: PMC7136838 DOI: 10.3389/fmicb.2020.00441] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 03/02/2020] [Indexed: 01/05/2023] Open
Abstract
Due to their fast growth rate and robustness, some haloalkalitolerant methanotrophs from the genus Methylotuvimicrobium have recently become not only promising biocatalysts for methane conversion but also favorable materials for obtaining fundamental knowledge on methanotrophs. Here, to realize unmarked genome modification in Methylotuvimicrobium bacteria, a counterselectable marker (CSM) was developed based on pheS, which encodes the α-subunit of phenylalanyl-tRNA synthetase. Two-point mutations (T252A and A306G) were introduced into PheS in Methylotuvimicrobium buryatense 5GB1C, generating PheS AG , which can recognize p-chloro-phenylalanine (p-Cl-Phe) as a substrate. Theoretically, the expression of PheS AG in a cell will result in the incorporation of p-Cl-Phe into proteins, leading to cell death. The P tac promoter and the ribosome-binding site region of mmoX were employed to control pheS AG , producing the pheS AG -3 CSM. M. buryatense 5GB1C harboring pheS AG -3 was extremely sensitive to 0.5 mM p-Cl-Phe. Then, a positive and counterselection cassette, PZ (only 1.5 kb in length), was constructed by combining pheS AG -3 and the zeocin resistance gene. A PZ- and PCR-based strategy was used to create the unmarked deletion of glgA1 or the whole smmo operon in M. buryatense 5GB1C and Methylotuvimicrobium alcaliphilum 20Z. The positive rates were over 92%, and the process could be accomplished in as few as eight days.
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Affiliation(s)
- Yongchuang Liu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Xiangrong He
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Pingping Zhu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Minggen Cheng
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Qing Hong
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Xin Yan
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
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Bioproduction of Isoprenoids and Other Secondary Metabolites Using Methanotrophic Bacteria as an Alternative Microbial Cell Factory Option: Current Stage and Future Aspects. Catalysts 2019. [DOI: 10.3390/catal9110883] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Methane is a promising carbon feedstock for industrial biomanufacturing because of its low price and high abundance. Recent advances in metabolic engineering and systems biology in methanotrophs have made it possible to produce a variety of value-added compounds from methane, including secondary metabolites. Isoprenoids are one of the largest family of secondary metabolites and have many useful industrial applications. In this review, we highlight the current efforts invested to methanotrophs for the production of isoprenoids and other secondary metabolites, including riboflavin and ectoine. The future outlook for improving secondary metabolites production (especially of isoprenoids) using metabolic engineering of methanotrophs is also discussed.
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Development of a CRISPR/Cas9 System for Methylococcus capsulatus In Vivo Gene Editing. Appl Environ Microbiol 2019; 85:AEM.00340-19. [PMID: 30926729 PMCID: PMC6532038 DOI: 10.1128/aem.00340-19] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 03/22/2019] [Indexed: 12/26/2022] Open
Abstract
In this study, we targeted the development and evaluation of broad-host-range CRISPR/Cas9 gene-editing tools in order to enhance the genetic-engineering capabilities of an industrially relevant methanotrophic biocatalyst. The CRISPR/Cas9 system developed in this study expands the genetic tools available to define molecular mechanisms in methanotrophic bacteria and has the potential to foster advances in the generation of novel biocatalysts to produce biofuels, platform chemicals, and high-value products from natural gas- and biogas-derived methane. Further, due to the broad-host-range applicability, these genetic tools may also enable innovative approaches to overcome the barriers associated with genetically engineering diverse, industrially promising nonmodel microorganisms. Methanotrophic bacteria play a crucial role in the Earth’s biogeochemical cycle and have the potential to be employed in industrial biomanufacturing processes due to their capacity to use natural gas- and biogas-derived methane as a sole carbon and energy source. Advanced gene-editing systems have the potential to enable rapid, high-throughput methanotrophic genetics and biocatalyst development. To this end, we employed a series of broad-host-range expression plasmids to construct a conjugatable clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 gene-editing system in Methylococcus capsulatus (Bath). Heterologous coexpression of the Streptococcus pyogenes Cas9 endonuclease and a synthetic single guide RNA (gRNA) showed efficient Cas9 DNA targeting and double-stranded DNA (dsDNA) cleavage that resulted in cell death. We demonstrated effective in vivo editing of plasmid DNA using both Cas9 and Cas9D10A nickase to convert green fluorescent protein (GFP)- to blue fluorescent protein (BFP)-expressing cells with 71% efficiency. Further, we successfully introduced a premature stop codon into the soluble methane monooxygenase (sMMO) hydroxylase component-encoding mmoX gene with the Cas9D10A nickase, disrupting sMMO function. These data provide proof of concept for CRISPR/Cas9-mediated gene editing in M. capsulatus. Given the broad-host-range replicons and conjugation capability of these CRISPR/Cas9 tools, they have potential utility in other methanotrophs and a wide array of Gram-negative microorganisms. IMPORTANCE In this study, we targeted the development and evaluation of broad-host-range CRISPR/Cas9 gene-editing tools in order to enhance the genetic-engineering capabilities of an industrially relevant methanotrophic biocatalyst. The CRISPR/Cas9 system developed in this study expands the genetic tools available to define molecular mechanisms in methanotrophic bacteria and has the potential to foster advances in the generation of novel biocatalysts to produce biofuels, platform chemicals, and high-value products from natural gas- and biogas-derived methane. Further, due to the broad-host-range applicability, these genetic tools may also enable innovative approaches to overcome the barriers associated with genetically engineering diverse, industrially promising nonmodel microorganisms.
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Tanaka K, Yokoe S, Igarashi K, Takashino M, Ishikawa M, Hori K, Nakanishi S, Kato S. Extracellular Electron Transfer via Outer Membrane Cytochromes in a Methanotrophic Bacterium Methylococcus capsulatus (Bath). Front Microbiol 2018; 9:2905. [PMID: 30555443 PMCID: PMC6281684 DOI: 10.3389/fmicb.2018.02905] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 11/13/2018] [Indexed: 11/24/2022] Open
Abstract
Electron exchange reactions between microbial cells and solid materials, referred to as extracellular electron transfer (EET), have attracted attention in the fields of microbial physiology, microbial ecology, and biotechnology. Studies of model species of iron-reducing, or equivalently, current-generating bacteria such as Geobacter spp. and Shewanella spp. have revealed that redox-active proteins, especially outer membrane c-type cytochromes (OMCs), play a pivotal role in the EET process. Recent (meta)genomic analyses have revealed that diverse microorganisms that have not been demonstrated to have EET ability also harbor OMC-like proteins, indicating that EET via OMCs could be more widely preserved in microorganisms than originally thought. A methanotrophic bacterium Methylococcus capsulatus (Bath) was reported to harbor multiple OMC genes whose expression is elevated by Cu starvation. However, the physiological role of these genes is unknown. Therefore, in this study, we explored whether M. capsulatus (Bath) displays EET abilities via OMCs. In electrochemical analysis, M. capsulatus (Bath) generated anodic current only when electron donors such as formate were available, and could reduce insoluble iron oxides in the presence of electron donor compounds. Furthermore, the current-generating and iron-reducing activities of M. capsulatus (Bath) cells that were cultured in a Cu-deficient medium, which promotes high levels of OMC expression, were higher than those cultured in a Cu-supplemented medium. Anodic current production by the Cu-deficient cells was significantly suppressed by disruption of MCA0421, a highly expressed OMC gene, and by treatment with carbon monoxide (CO) gas (an inhibitor of c-type cytochromes). Our results provide evidence of EET in M. capsulatus (Bath) and demonstrate the pivotal role of OMCs in this process. This study raises the possibility that EET to solid compounds is a novel survival strategy of methanotrophic bacteria.
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Affiliation(s)
- Kenya Tanaka
- Graduate School of Engineering Science, Osaka University, Toyonaka, Japan
| | - Sho Yokoe
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan
| | - Kensuke Igarashi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Sapporo, Japan
| | - Motoko Takashino
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Sapporo, Japan
| | - Masahito Ishikawa
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan.,Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Katsutoshi Hori
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, Japan
| | - Shuji Nakanishi
- Graduate School of Engineering Science, Osaka University, Toyonaka, Japan.,Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Souichiro Kato
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Sapporo, Japan.,Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
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