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Böer T, Engelhardt L, Lüschen A, Eysell L, Yoshida H, Schneider D, Angenent LT, Basen M, Daniel R, Poehlein A. Isolation and characterization of novel acetogenic Moorella strains for employment as potential thermophilic biocatalysts. FEMS Microbiol Ecol 2024; 100:fiae109. [PMID: 39118367 PMCID: PMC11328732 DOI: 10.1093/femsec/fiae109] [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: 03/25/2024] [Revised: 06/05/2024] [Accepted: 08/07/2024] [Indexed: 08/10/2024] Open
Abstract
Thermophilic acetogenic bacteria have attracted attention as promising candidates for biotechnological applications such as syngas fermentation, microbial electrosynthesis, and methanol conversion. Here, we aimed to isolate and characterize novel thermophilic acetogens from diverse environments. Enrichment of heterotrophic and autotrophic acetogens was monitored by 16S rRNA gene-based bacterial community analysis. Seven novel Moorella strains were isolated and characterized by genomic and physiological analyses. Two Moorella humiferrea isolates showed considerable differences during autotrophic growth. The M. humiferrea LNE isolate (DSM 117358) fermented carbon monoxide (CO) to acetate, while the M. humiferrea OCP isolate (DSM 117359) transformed CO to hydrogen and carbon dioxide (H2 + CO2), employing the water-gas shift reaction. Another carboxydotrophic hydrogenogenic Moorella strain was isolated from the covering soil of an active charcoal burning pile and proposed as the type strain (ACPsT) of the novel species Moorella carbonis (DSM 116161T and CCOS 2103T). The remaining four novel strains were affiliated with Moorella thermoacetica and showed, together with the type strain DSM 2955T, the production of small amounts of ethanol from H2 + CO2 in addition to acetate. The physiological analyses of the novel Moorella strains revealed isolate-specific differences that considerably increase the knowledge base on thermophilic acetogens for future applications.
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Affiliation(s)
- Tim Böer
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Lisa Engelhardt
- Microbiology, Institute of Biological Sciences, University Rostock, 18059 Rostock, Germany
| | - Alina Lüschen
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Lena Eysell
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Hiroki Yoshida
- Environmental Biotechnology Group, Department of Geosciences, University of Tübingen, 72074 Tübingen, Germany
| | - Dominik Schneider
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Largus T Angenent
- Environmental Biotechnology Group, Department of Geosciences, University of Tübingen, 72074 Tübingen, Germany
| | - Mirko Basen
- Microbiology, Institute of Biological Sciences, University Rostock, 18059 Rostock, Germany
| | - Rolf Daniel
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Anja Poehlein
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
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Niu C, Zhao X, Shi D, Ying Y, Wu M, Lai CY, Guo J, Hu S, Liu T. Bioreduction of chromate in a syngas-based membrane biofilm reactor. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134195. [PMID: 38581872 DOI: 10.1016/j.jhazmat.2024.134195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 03/07/2024] [Accepted: 03/31/2024] [Indexed: 04/08/2024]
Abstract
This study leveraged synthesis gas (syngas), a renewable resource attainable through the gasification of biowaste, to achieve efficient chromate removal from water. To enhance syngas transfer efficiency, a membrane biofilm reactor (MBfR) was employed. Long-term reactor operation showed a stable and high-level chromate removal efficiency > 95%, yielding harmless Cr(III) precipitates, as visualised by scanning electron microscopy and energy dispersive X-ray analysis. Corresponding to the short hydraulic retention time of 0.25 days, a high chromate removal rate of 80 µmol/L/d was attained. In addition to chromate reduction, in situ production of volatile fatty acids (VFAs) by gas fermentation was observed. Three sets of in situ batch tests and two groups of ex situ batch tests jointly unravelled the mechanisms, showing that biological chromate reduction was primarily driven by VFAs produced from in situ syngas fermentation, whereas hydrogen originally present in the syngas played a minor role. 16 S rRNA gene amplicon sequencing has confirmed the enrichment of syngas-fermenting bacteria (such as Sporomusa), who performed in situ gas fermentation leading to the synthesis of VFAs, and organics-utilising bacteria (such as Aquitalea), who utilised VFAs to drive chromate reduction. These findings, combined with batch assays, elucidate the pathways orchestrating synergistic interactions between fermentative microbial cohorts and chromate-reducing microorganisms. The findings facilitate the development of cost-effective strategies for groundwater and drinking water remediation and present an alternative application scenario for syngas.
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Affiliation(s)
- Chenkai Niu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Xinyu Zhao
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Danting Shi
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 999077, Hong Kong Special Administrative Region of China
| | - Yifeng Ying
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Mengxiong Wu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Chun-Yu Lai
- College of Environmental and Resource Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Shihu Hu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Tao Liu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia; Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 999077, Hong Kong Special Administrative Region of China.
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Colucci Cante R, Nigro F, Passannanti F, Lentini G, Gallo M, Nigro R, Budelli AL. Gut health benefits and associated systemic effects provided by functional components from the fermentation of natural matrices. Compr Rev Food Sci Food Saf 2024; 23:e13356. [PMID: 38767859 DOI: 10.1111/1541-4337.13356] [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: 10/09/2023] [Revised: 02/26/2024] [Accepted: 04/06/2024] [Indexed: 05/22/2024]
Abstract
Recently, the role of the gut microbiota in metabolic health, immunity, behavioral balance, longevity, and intestine comfort has been the object of several studies from scientific communities. They were encouraged by a growing interest from food industries and consumers toward novel fermented ingredients and formulations with powerful biological effects, such as pre, pro, and postbiotic products. Depending on the selected strains, the operating conditions, the addition of suitable reagents or enzymes, the equipment, and the reactor configurations, functional compounds with high bioactivity, such as short-chain fatty acids, gamma-aminobutyric acid, bioactive peptides, and serotonin, can be enhanced and/or produced through fermentation of several vegetable matrices. Otherwise, their formation can also be promoted directly in the gut after the dietary intake of fermented foods: In this case, fermentation will aim to increase the content of precursor substances, such as indigestible fibers, polyphenols, some amino acids, and resistant starch, which can be potentially metabolized by endogenous gut microorganisms and converted in healthy molecules. This review provides an overview of the main functional components currently investigated in literature and the associated gut health benefits. The current state of the art about fermentation technology as a promising functionalization tool to promote the direct or indirect formation of gut-health-enhancing components was deepened, highlighting the importance of optimizing microorganism selection, system setups, and process conditions according to the target compound of interest. The collected data suggested the possibility of gaining novel functional food ingredients or products rich in functional molecules through fermentation without performing additional extraction and purification stages, which are needed when conventional culture broths are used.
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Affiliation(s)
- Rosa Colucci Cante
- Department of Chemical Engineering, Materials, and Industrial Production, University of Naples Federico II, Naples, Italy
- Department of Industrial Engineering, University of Niccolò Cusano, Rome, Italy
| | - Federica Nigro
- I. T. P. Innovation and Technology Provider S.r.l., Naples, Italy
| | - Francesca Passannanti
- Department of Chemical Engineering, Materials, and Industrial Production, University of Naples Federico II, Naples, Italy
- I. T. P. Innovation and Technology Provider S.r.l., Naples, Italy
| | - Giulia Lentini
- Department of Chemical Engineering, Materials, and Industrial Production, University of Naples Federico II, Naples, Italy
| | - Marianna Gallo
- Department of Chemical Engineering, Materials, and Industrial Production, University of Naples Federico II, Naples, Italy
- Department of Industrial Engineering, University of Niccolò Cusano, Rome, Italy
- I. T. P. Innovation and Technology Provider S.r.l., Naples, Italy
| | - Roberto Nigro
- Department of Chemical Engineering, Materials, and Industrial Production, University of Naples Federico II, Naples, Italy
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Jia D, Deng W, Hu P, Jiang W, Gu Y. Thermophilic Moorella thermoacetica as a platform microorganism for C1 gas utilization: physiology, engineering, and applications. BIORESOUR BIOPROCESS 2023; 10:61. [PMID: 38647965 PMCID: PMC10992200 DOI: 10.1186/s40643-023-00682-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 08/29/2023] [Indexed: 04/25/2024] Open
Abstract
In the context of the rapid development of low-carbon economy, there has been increasing interest in utilizing naturally abundant and cost-effective one-carbon (C1) substrates for sustainable production of chemicals and fuels. Moorella thermoacetica, a model acetogenic bacterium, has attracted significant attention due to its ability to utilize carbon dioxide (CO2) and carbon monoxide (CO) via the Wood-Ljungdahl (WL) pathway, thereby showing great potential for the utilization of C1 gases. However, natural strains of M. thermoacetica are not yet fully suitable for industrial applications due to their limitations in carbon assimilation and conversion efficiency as well as limited product range. Over the past decade, progresses have been made in the development of genetic tools for M. thermoacetica, accelerating the understanding and modification of this acetogen. Here, we summarize the physiological and metabolic characteristics of M. thermoacetica and review the recent advances in engineering this bacterium. Finally, we propose the future directions for exploring the real potential of M. thermoacetica in industrial applications.
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Affiliation(s)
- Dechen Jia
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wangshuying Deng
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Peng Hu
- Shanghai GTLB Biotech Co., Ltd, 1688 North Guoquan Road, Shanghai, 200438, China
| | - Weihong Jiang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Yang Gu
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China.
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Harahap BM, Ahring BK. Acetate Production from Syngas Produced from Lignocellulosic Biomass Materials along with Gaseous Fermentation of the Syngas: A Review. Microorganisms 2023; 11:microorganisms11040995. [PMID: 37110418 PMCID: PMC10143712 DOI: 10.3390/microorganisms11040995] [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: 02/22/2023] [Revised: 04/05/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Biotransformation of lignocellulose-derived synthetic gas (syngas) into acetic acid is a promising way of creating biochemicals from lignocellulosic waste materials. Acetic acid has a growing market with applications within food, plastics and for upgrading into a wide range of biofuels and bio-products. In this paper, we will review the microbial conversion of syngas to acetic acid. This will include the presentation of acetate-producing bacterial strains and their optimal fermentation conditions, such as pH, temperature, media composition, and syngas composition, to enhance acetate production. The influence of syngas impurities generated from lignocellulose gasification will further be covered along with the means to alleviate impurity problems through gas purification. The problem with mass transfer limitation of gaseous fermentation will further be discussed as well as ways to improve gas uptake during the fermentation.
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Affiliation(s)
- Budi Mandra Harahap
- Bioproducts, Science, and Engineering Laboratory, Washington State University Tri-Cities, 2710, Crimson Way, Richland, WA 99354, USA
- Department of Biological System Engineering, Washington State University, L. J. Smith Hall, Pullman, WA 99164, USA
| | - Birgitte K Ahring
- Bioproducts, Science, and Engineering Laboratory, Washington State University Tri-Cities, 2710, Crimson Way, Richland, WA 99354, USA
- Department of Biological System Engineering, Washington State University, L. J. Smith Hall, Pullman, WA 99164, USA
- Voiland School of Chemical Engineering and Bioengineering, Washington State University, Wegner Hall, Pullman, WA 99164, USA
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Olivier A, Desgagnés A, Mercier E, Iliuta MC. New Insights on Catalytic Valorization of Carbon Dioxide by Conventional and Intensified Processes. Ind Eng Chem Res 2023. [DOI: 10.1021/acs.iecr.3c00064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Affiliation(s)
- Antoine Olivier
- Department of Chemical Engineering, Laval University, Québec, G1 V 0A6, Canada
| | - Alex Desgagnés
- Department of Chemical Engineering, Laval University, Québec, G1 V 0A6, Canada
| | - Etienne Mercier
- Department of Chemical Engineering, Laval University, Québec, G1 V 0A6, Canada
| | - Maria C. Iliuta
- Department of Chemical Engineering, Laval University, Québec, G1 V 0A6, Canada
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7
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Liu H, Arbing MA, Bowie JU. Expanding the use of ethanol as a feedstock for cell-free synthetic biochemistry by implementing acetyl-CoA and ATP generating pathways. Sci Rep 2022; 12:7700. [PMID: 35546163 PMCID: PMC9095697 DOI: 10.1038/s41598-022-11653-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 04/20/2022] [Indexed: 12/01/2022] Open
Abstract
Ethanol is a widely available carbon compound that can be increasingly produced with a net negative carbon balance. Carbon-negative ethanol might therefore provide a feedstock for building a wider range of sustainable chemicals. Here we show how ethanol can be converted with a cell free system into acetyl-CoA, a central precursor for myriad biochemicals, and how we can use the energy stored in ethanol to generate ATP, another key molecule important for powering biochemical pathways. The ATP generator produces acetone as a value-added side product. Our ATP generator reached titers of 27 ± 6 mM ATP and 59 ± 15 mM acetone with maximum ATP synthesis rate of 2.8 ± 0.6 mM/h and acetone of 7.8 ± 0.8 mM/h. We illustrated how the ATP generating module can power cell-free biochemical pathways by converting mevalonate into isoprenol at a titer of 12.5 ± 0.8 mM and a maximum productivity of 1.0 ± 0.05 mM/h. These proof-of-principle demonstrations may ultimately find their way to the manufacture of diverse chemicals from ethanol and other simple carbon compounds.
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Affiliation(s)
- Hongjiang Liu
- Department of Chemistry and Biochemistry, Molecular Biology Institute, UCLA-DOE Institute of Genomics and Proteomics, University of California Los Angeles, Boyer Hall, 611 Charles E. Young Dr. E, Los Angeles, CA, 90095-1570, USA
| | - Mark A Arbing
- Department of Chemistry and Biochemistry, Molecular Biology Institute, UCLA-DOE Institute of Genomics and Proteomics, University of California Los Angeles, Boyer Hall, 611 Charles E. Young Dr. E, Los Angeles, CA, 90095-1570, USA
| | - James U Bowie
- Department of Chemistry and Biochemistry, Molecular Biology Institute, UCLA-DOE Institute of Genomics and Proteomics, University of California Los Angeles, Boyer Hall, 611 Charles E. Young Dr. E, Los Angeles, CA, 90095-1570, USA.
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8
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Merli G, Becci A, Amato A, Beolchini F. Acetic acid bioproduction: The technological innovation change. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 798:149292. [PMID: 34375263 DOI: 10.1016/j.scitotenv.2021.149292] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/16/2021] [Accepted: 07/23/2021] [Indexed: 06/13/2023]
Abstract
Acetic acid is an organic acid of great importance globally and the demand of this product is currently increasing. The production of this acid has consequently aroused more and more interest over the years, especially for more sustainable processes. From a biological point of view, acetic acid can be produced by acetogenesis using inorganic substrates like CO2 or CO (with acetogenic bacteria) and aerobic fermentation (with acetic acid bacteria or fungi). With the aim of investigating the progress of technological innovation, the methodology applied by this review was an analysis of the international patents with the Espacenet platform, which ensured a worldwide invention overview. Another criterion was the selection of a precise period of time, from 1990 to 2020. A patent review is able to create an overview of the inventions designed for the real scale implementation, providing a whole picture of the state of the art of the technological innovation change. In addition, the most representative works of literature, that consider the influence of operating conditions (T, pH, oxygenation), have been analysed for each process. The present review, with an innovative approach focused on the technological innovation change, highlighted the ongoing interest for acetic acid bioproduction by acetogenic and acetic acid bacteria. The number of patents related to acetic acid bacteria was consistent also in the past years, but recently the interest is moving forward the utilization of genetic engineering (36% of the patents) and new substrates, like agriculture waste (26% of the patens), responding to circular economy principles. On the other hand, the acetic acid production by acetogenic bacteria is most recent, with over the 90% of the patents developed in the last 10 years. In this case the interest is mainly focused on the use of synthesis gas as substrate, that could increase the process sustainability.
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Affiliation(s)
- Giulia Merli
- Department of Life and Environmental Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy
| | - Alessandro Becci
- Department of Life and Environmental Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy.
| | - Alessia Amato
- Department of Life and Environmental Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy
| | - Francesca Beolchini
- Department of Life and Environmental Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy
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Shimizu H, Toya Y. Recent advances in metabolic engineering-integration of in silico design and experimental analysis of metabolic pathways. J Biosci Bioeng 2021; 132:429-436. [PMID: 34509367 DOI: 10.1016/j.jbiosc.2021.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 08/07/2021] [Indexed: 11/29/2022]
Abstract
Microorganisms are widely used to produce valuable compounds. Because thousands of metabolic reactions occur simultaneously and many metabolic reactions are related to target production and cell growth, the development of a rational design method for metabolic pathway modification to optimize target production is needed. In this paper, recent advances in metabolic engineering are reviewed, specifically considering computational pathway modification design and experimental evaluation of metabolic fluxes by 13C-metabolic flux analysis. Computational tools for seeking effective gene deletion targets and recruiting heterologous genes are described in flux balance analysis approaches. A kinetic model and adaptive laboratory evolution were applied to identify and eliminate the rate-limiting step in metabolic pathways. Data science-based approaches for process monitoring and control are described to maximize the performance of engineered cells in bioreactors.
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Affiliation(s)
- Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Yoshihiro Toya
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
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10
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Watanabe K, Perez CMT, Kitahori T, Hata K, Aoi M, Takahashi H, Sakuma T, Okamura Y, Nakashimada Y, Yamamoto T, Matsuyama K, Mayuzumi S, Aki T. Improvement of fatty acid productivity of thraustochytrid, Aurantiochytrium sp. by genome editing. J Biosci Bioeng 2020; 131:373-380. [PMID: 33386277 DOI: 10.1016/j.jbiosc.2020.11.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 11/26/2020] [Accepted: 11/27/2020] [Indexed: 01/12/2023]
Abstract
Thraustochytrid strains belonging to the genus Aurantiochytrium accumulate significant amounts of lipids including polyunsaturated fatty acids and carotenoids and, therefore, are expected to be used for industrial production of various valuable materials. Although various efforts such as chemical mutagenesis and homologous gene recombination have been made to improve lipid productivity of Aurantiochytrium species, low specificity and efficiency in the conventional methods hinder the research progress. Here, we attempted to apply a genome editing technology, the CRISPR-Cas9 system as an alternative molecular breeding technique for Aurantiochytrium species to accelerate the metabolic engineering. The efficiency of specific gene knock-in by the homologous recombination increased more than 10-folds by combining the CRISPR-Cas9 system. As a result of disrupting the genes associated with β-oxidation of fatty acids by the improved method, the genome edited strains with higher fatty acid productivity were isolated, demonstrating for the first time that the CRISPR-Cas9 system was effective for molecular breeding of the strains in the genus Aurantiochytrium to improve lipid productivity.
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Affiliation(s)
- Kenshi Watanabe
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Charose Marie Ting Perez
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Tomoki Kitahori
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Kosuke Hata
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Masato Aoi
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Hirokazu Takahashi
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Tetsushi Sakuma
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Yoshiko Okamura
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Yutaka Nakashimada
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Takashi Yamamoto
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | | | - Shinzo Mayuzumi
- Idemitsu Kosan Co., Ltd., 1280 Kami-izumi, Sodegaura, Chiba 299-0293, Japan
| | - Tsunehiro Aki
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan.
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11
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Heffernan JK, Valgepea K, de Souza Pinto Lemgruber R, Casini I, Plan M, Tappel R, Simpson SD, Köpke M, Nielsen LK, Marcellin E. Enhancing CO 2-Valorization Using Clostridium autoethanogenum for Sustainable Fuel and Chemicals Production. Front Bioeng Biotechnol 2020; 8:204. [PMID: 32292775 PMCID: PMC7135887 DOI: 10.3389/fbioe.2020.00204] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 03/02/2020] [Indexed: 01/02/2023] Open
Abstract
Acetogenic bacteria can convert waste gases into fuels and chemicals. Design of bioprocesses for waste carbon valorization requires quantification of steady-state carbon flows. Here, steady-state quantification of autotrophic chemostats containing Clostridium autoethanogenum grown on CO2 and H2 revealed that captured carbon (460 ± 80 mmol/gDCW/day) had a significant distribution to ethanol (54 ± 3 C-mol% with a 2.4 ± 0.3 g/L titer). We were impressed with this initial result, but also observed limitations to biomass concentration and growth rate. Metabolic modeling predicted culture performance and indicated significant metabolic adjustments when compared to fermentation with CO as the carbon source. Moreover, modeling highlighted flux to pyruvate, and subsequently reduced ferredoxin, as a target for improving CO2 and H2 fermentation. Supplementation with a small amount of CO enabled co-utilization with CO2, and enhanced CO2 fermentation performance significantly, while maintaining an industrially relevant product profile. Additionally, the highest specific flux through the Wood-Ljungdahl pathway was observed during co-utilization of CO2 and CO. Furthermore, the addition of CO led to superior CO2-valorizing characteristics (9.7 ± 0.4 g/L ethanol with a 66 ± 2 C-mol% distribution, and 540 ± 20 mmol CO2/gDCW/day). Similar industrial processes are commercial or currently being scaled up, indicating CO-supplemented CO2 and H2 fermentation has high potential for sustainable fuel and chemical production. This work also provides a reference dataset to advance our understanding of CO2 gas fermentation, which can contribute to mitigating climate change.
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Affiliation(s)
- James K. Heffernan
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Saint Lucia, QLD, Australia
| | - Kaspar Valgepea
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Saint Lucia, QLD, Australia
- ERA Chair in Gas Fermentation Technologies, Institute of Technology, University of Tartu, Tartu, Estonia
| | | | - Isabella Casini
- Center for Applied Geosciences, University of Tübingen, Tübingen, Germany
| | - Manuel Plan
- Queensland Node of Metabolomics Australia, The University of Queensland, Saint Lucia, QLD, Australia
| | | | | | | | - Lars K. Nielsen
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Saint Lucia, QLD, Australia
- Queensland Node of Metabolomics Australia, The University of Queensland, Saint Lucia, QLD, Australia
| | - Esteban Marcellin
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Saint Lucia, QLD, Australia
- Queensland Node of Metabolomics Australia, The University of Queensland, Saint Lucia, QLD, Australia
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Omar B, El-Gammal M, Abou-Shanab R, Fotidis IA, Angelidaki I, Zhang Y. Biogas upgrading and biochemical production from gas fermentation: Impact of microbial community and gas composition. BIORESOURCE TECHNOLOGY 2019; 286:121413. [PMID: 31078978 DOI: 10.1016/j.biortech.2019.121413] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 05/01/2019] [Accepted: 05/02/2019] [Indexed: 06/09/2023]
Abstract
The present study proposes a novel alternative method of the current biogas upgrading techniques by converting CO2 (in the biogas) into valuable chemicals (e.g., volatile fatty acids) using H2 as energy source and acetogenic mixed culture as biocatalyst. The influence of thermal treatment (90 °C) on the inhibition of the methanogenic archaea and enriching the acetogenic bacteria in different inocula (mesophilic and thermophilic) was initially tested. The most efficient inoculum that achieved the highest performance through the fermentation process was further used to define the optimum H2/CO2 gas ratio that secures maximum production yield of chemicals and maximum biogas upgrading efficiency. In addition, 16S rRNA analysis of the microbial community was conducted at the end of the experimental period to target functional microbes. The maximum biogas content (77% (v/v)) and acetate yield (72%) were achieved for 2H2:1CO2 ratio (v/v), with Moorella sp. 4 as the most dominant thermophilic acetogenic bacterium.
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Affiliation(s)
- Basma Omar
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115, DK-2800 Kgs. Lyngby, Denmark; Department of Environmental Sciences, Faculty of Science, Damietta University, 34517 Damietta, Egypt
| | - Maie El-Gammal
- Department of Environmental Sciences, Faculty of Science, Damietta University, 34517 Damietta, Egypt
| | - Reda Abou-Shanab
- Department of Environmental Biotechnology, City of Scientific Research and Technology Applications, Alexandria 21934, Egypt
| | - Ioannis A Fotidis
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115, DK-2800 Kgs. Lyngby, Denmark
| | - Irini Angelidaki
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115, DK-2800 Kgs. Lyngby, Denmark
| | - Yifeng Zhang
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115, DK-2800 Kgs. Lyngby, Denmark.
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Emerson DF, Woolston BM, Liu N, Donnelly M, Currie DH, Stephanopoulos G. Enhancing hydrogen-dependent growth of and carbon dioxide fixation by Clostridium ljungdahlii through nitrate supplementation. Biotechnol Bioeng 2018; 116:294-306. [PMID: 30267586 DOI: 10.1002/bit.26847] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 09/23/2018] [Accepted: 09/28/2018] [Indexed: 12/15/2022]
Abstract
Synthesis gas (syngas) fermentation via the Wood-Ljungdahl pathway is receiving growing attention as a possible platform for the fixation of CO 2 and renewable production of fuels and chemicals. However, the pathway operates near the thermodynamic limit of life, resulting in minimal adenosine triphosphate (ATP) production and long doubling times. This calls into question the feasibility of producing high-energy compounds at industrially relevant levels. In this study, we investigated the possibility of co-utilizing nitrate as an inexpensive additional electron acceptor to enhance ATP production during H 2 -dependent growth of Clostridium ljungdahlii, Moorella thermoacetica, and Acetobacterium woodii. In contrast to other acetogens tested, growth rate and final biomass titer were improved for C. ljungdahlii growing on a mixture of H 2 and CO 2 when supplemented with nitrate. Transcriptomic analysis, 13 CO 2 labeling, and an electron balance were used to understand how electron flux was partitioned between CO 2 and nitrate. We further show that, with nitrate supplementation, the ATP/adenosine diphosphate (ADP) ratio and acetyl-CoA pools were increased by fivefold and threefold, respectively, suggesting that this strategy could be useful for the production of ATP-intensive heterologous products from acetyl-CoA. Finally, we propose a pathway for enhanced ATP production from nitrate and use this as a basis to calculate theoretical yields for a variety of products. This study demonstrates a viable strategy for the decoupling of ATP production from carbon dioxide fixation, which will serve to significantly improve the CO 2 fixation rate and the production metrics of other chemicals from CO 2 and H 2 in this host.
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Affiliation(s)
- David F Emerson
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Benjamin M Woolston
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Nian Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Mackenzie Donnelly
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Devin H Currie
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Gregory Stephanopoulos
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
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Homolactic Acid Fermentation by the Genetically Engineered Thermophilic Homoacetogen Moorella thermoacetica ATCC 39073. Appl Environ Microbiol 2017; 83:AEM.00247-17. [PMID: 28159797 DOI: 10.1128/aem.00247-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 01/31/2017] [Indexed: 11/20/2022] Open
Abstract
For the efficient production of target metabolites from carbohydrates, syngas, or H2-CO2 by genetically engineered Moorella thermoacetica, the control of acetate production (a main metabolite of M. thermoacetica) is desired. Although propanediol utilization protein (PduL) was predicted to be a phosphotransacetylase (PTA) involved in acetate production in M. thermoacetica, this has not been confirmed. Our findings described herein directly demonstrate that two putative PduL proteins, encoded by Moth_0864 (pduL1) and Moth_1181 (pduL2), are involved in acetate formation as PTAs. To disrupt these genes, we replaced each gene with a lactate dehydrogenase gene from Thermoanaerobacter pseudethanolicus ATCC 33223 (T-ldh). The acetate production from fructose as the sole carbon source by the pduL1 deletion mutant was not deficient, whereas the disruption of pduL2 significantly decreased the acetate yield to approximately one-third that of the wild-type strain. The double-deletion (both pduL genes) mutant did not produce acetate but produced only lactate as the end product from fructose. These results suggest that both pduL genes are associated with acetate formation via acetyl-coenzyme A (acetyl-CoA) and that their disruption enables a shift in the homoacetic pathway to the genetically synthesized homolactic pathway via pyruvate.IMPORTANCE This is the first report, to our knowledge, on the experimental identification of PTA genes in M. thermoacetica and the shift of the native homoacetic pathway to the genetically synthesized homolactic pathway by their disruption on a sugar platform.
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Enhancement of acetate productivity in a thermophilic (55 °C) hollow-fiber membrane biofilm reactor with mixed culture syngas (H2/CO2) fermentation. Appl Microbiol Biotechnol 2017; 101:2619-2627. [DOI: 10.1007/s00253-017-8124-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 12/26/2016] [Accepted: 01/10/2017] [Indexed: 11/25/2022]
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16
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Schlager S, Haberbauer M, Fuchsbauer A, Hemmelmair C, Dumitru LM, Hinterberger G, Neugebauer H, Sariciftci NS. Bio-Electrocatalytic Application of Microorganisms for Carbon Dioxide Reduction to Methane. CHEMSUSCHEM 2017; 10:226-233. [PMID: 27792284 PMCID: PMC5248612 DOI: 10.1002/cssc.201600963] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 08/30/2016] [Indexed: 06/06/2023]
Abstract
We present a study on a microbial electrolysis cell with methanogenic microorganisms adapted to reduce CO2 to CH4 with the direct injection of electrons and without the artificial addition of H2 or an additional carbon source except gaseous CO2 . This is a new approach in comparison to previous work in which both bicarbonate and gaseous CO2 served as the carbon source. The methanogens used are known to perform well in anaerobic reactors and metabolize H2 and CO2 to CH4 and water. This study shows the biofilm formation of those microorganisms on a carbon felt electrode and the long-term performance for CO2 reduction to CH4 using direct electrochemical reduction. CO2 reduction is performed simply by electron uptake with gaseous CO2 as the sole carbon source in a defined medium. This "electrometabolism" in such microbial electrolysis cells depends strongly on the potential applied as well as on the environmental conditions. We investigated the performance using different adaption mechanisms and a constant potential of -700 mV vs. Ag/AgCl for CH4 generation at 30-35 °C. The experiments were performed by using two-compartment electrochemical cells. Production rates with Faradaic efficiencies of around 22 % were observed.
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Affiliation(s)
- Stefanie Schlager
- Linz Institute for Organic Solar CellsJohannes Kepler University LinzAltenbergerstraße 694040LinzAustria
| | | | | | | | - Liviu Mihai Dumitru
- Linz Institute for Organic Solar CellsJohannes Kepler University LinzAltenbergerstraße 694040LinzAustria
| | - Gabriele Hinterberger
- Linz Institute for Organic Solar CellsJohannes Kepler University LinzAltenbergerstraße 694040LinzAustria
| | - Helmut Neugebauer
- Linz Institute for Organic Solar CellsJohannes Kepler University LinzAltenbergerstraße 694040LinzAustria
| | - Niyazi Serdar Sariciftci
- Linz Institute for Organic Solar CellsJohannes Kepler University LinzAltenbergerstraße 694040LinzAustria
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17
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Moiseev II. Biotechnology is storming the heights of petrochemistry. KINETICS AND CATALYSIS 2016. [DOI: 10.1134/s0023158416040078] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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18
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Yang C, Mi L, Hu X, Liu J, Wang J. Investigation into Host Selection of the Cecal Acetogen Population in Rabbits after Weaning. PLoS One 2016; 11:e0158768. [PMID: 27379387 PMCID: PMC4933399 DOI: 10.1371/journal.pone.0158768] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 06/18/2016] [Indexed: 01/13/2023] Open
Abstract
Homoacetogenic bacteria have received attention as a hydrogenotrophic population that offers a significant energetic advantage to the host animal. Reductive acetogenesis is likely an important hydrogen disposal mechanism in the cecum of rabbits. However, molecular ecology information about cecal acetogen candidates has rarely been reported. To better understand the effect of host selection in the rabbit cecal acetogen community with respect to growth, rabbits at four different age stages (30, 60, 120 and 180 days) with the same diet were studied. Although the abundance of potential acetogens and methanogens was high in the cecum of rabbits undergoing growth, many novel potential acetogen populations were observed in the cecum of rabbits across all age groups. Young and adult rabbits had their own distinct acetogen community although they received the same diet, which suggests that as the rabbit ages, acetogens in the cecum undergo developmental changes because of host selection that are independent of diet, and perhaps the different acetogen communities result in different hydrogenotrophic characteristics. The within-group similarity increased with age, indicating that the acetogen community converges to a more homogeneous and stable arrangement with aging.
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Affiliation(s)
- Chunlei Yang
- Institute of Dairy Science, MoE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lan Mi
- Institute of Dairy Science, MoE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xialu Hu
- Institute of Dairy Science, MoE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jianxin Liu
- Institute of Dairy Science, MoE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiakun Wang
- Institute of Dairy Science, MoE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
- * E-mail:
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19
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Pal P, Nayak J. Acetic Acid Production and Purification: Critical Review Towards Process Intensification. SEPARATION AND PURIFICATION REVIEWS 2016. [DOI: 10.1080/15422119.2016.1185017] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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20
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Shen Y, Jarboe L, Brown R, Wen Z. A thermochemical–biochemical hybrid processing of lignocellulosic biomass for producing fuels and chemicals. Biotechnol Adv 2015; 33:1799-813. [DOI: 10.1016/j.biotechadv.2015.10.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 10/16/2015] [Accepted: 10/16/2015] [Indexed: 12/28/2022]
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Xue J, Isern NG, Ewing RJ, Liyu AV, Sears JA, Knapp H, Iversen J, Sisk DR, Ahring BK, Majors PD. New generation NMR bioreactor coupled with high-resolution NMR spectroscopy leads to novel discoveries in Moorella thermoacetica metabolic profiles. Appl Microbiol Biotechnol 2014; 98:8367-75. [PMID: 24946863 DOI: 10.1007/s00253-014-5847-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 05/13/2014] [Accepted: 05/22/2014] [Indexed: 11/26/2022]
Abstract
An in situ nuclear magnetic resonance (NMR) bioreactor was developed and employed to monitor microbial metabolism under batch growth conditions in real time. We selected Moorella thermoacetica ATCC 49707 as a test case. M. thermoacetica (formerly Clostridium thermoaceticum) is a strictly anaerobic, thermophilic, acetogenic, gram-positive bacterium with potential for industrial production of chemicals. The metabolic profiles of M. thermoacetica were characterized during growth in batch mode on xylose (a component of lignocellulosic biomass) using the new generation NMR bioreactor in combination with high-resolution NMR (HR-NMR) spectroscopy. In situ NMR measurements were performed using water-suppressed H-1 NMR spectroscopy at 500 MHz, and aliquots of the bioreactor contents were taken for 600-MHz HR-NMR spectroscopy at specific intervals to confirm metabolite identifications and expand metabolite coverage. M. thermoacetica demonstrated the metabolic potential to produce formate, ethanol, and methanol from xylose, in addition to its known capability of producing acetic acid. Real-time monitoring of bioreactor conditions showed a temporary pH decrease, with a concomitant increase in formic acid during exponential growth. Fermentation experiments performed outside of the magnet showed that the strong magnetic field employed for NMR detection did not significantly affect cell metabolism. Use of the in situ NMR bioreactor facilitated monitoring of the fermentation process, enabling identification of intermediate and endpoint metabolites and their correlation with pH and biomass produced during culture growth. Real-time monitoring of culture metabolism using the NMR bioreactor in combination with HR-NMR spectroscopy will allow optimization of the metabolism of microorganisms producing valuable bioproducts.
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Affiliation(s)
- Junfeng Xue
- Bioproducts, Sciences and Engineering Laboratory, Washington State University Tri-Cities, 2710 Crimson Way, Richland, WA, 99354-1671, USA
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22
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Reed PT, Izquierdo JA, Lynd LR. Cellulose fermentation by Clostridium thermocellum and a mixed consortium in an automated repetitive batch reactor. BIORESOURCE TECHNOLOGY 2014; 155:50-6. [PMID: 24413481 DOI: 10.1016/j.biortech.2013.12.051] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 12/10/2013] [Accepted: 12/12/2013] [Indexed: 05/02/2023]
Abstract
An automated repetitive batch fermentation system was developed to facilitate the study of microbial cellulose utilization. The system was operated with Avicel as the carbon source and either Clostridium thermocellum ATCC 27405 or a consortium enriched from compost as inocula. Multiple cycles of growth medium addition, incubation, and medium removal were performed with each inoculum. Removal and addition of media were automatically initiated when CO2 production fell to 90% of the cycle's peak. A strong correlation was observed between CO2 production and cellulose consumption, suggesting that the online signal was a good proxy for substrate utilization. Both cultures exhibited accelerated substrate utilization and a decrease in cycle time. About the same number of cycles was required to reach maximum CO2 production for both cultures. Notably, the magnitudes of the maximum CO2 production rate and cycle times were very similar for both C. thermocellum in pure culture and an environmental consortium.
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Affiliation(s)
- Parker T Reed
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States; BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Javier A Izquierdo
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States; BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Lee R Lynd
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States; BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
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23
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Hu P, Rismani-Yazdi H, Stephanopoulos G. Anaerobic CO2fixation by the acetogenic bacteriumMoorella thermoacetica. AIChE J 2013. [DOI: 10.1002/aic.14127] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Peng Hu
- Dept. of Chemical Engineering; Massachusetts Institute of Technology; Cambridge; MA; 02139
| | - Hamid Rismani-Yazdi
- Dept. of Chemical Engineering; Massachusetts Institute of Technology; Cambridge; MA; 02139
| | - Gregory Stephanopoulos
- Dept. of Chemical Engineering; Massachusetts Institute of Technology; Cambridge; MA; 02139
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24
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Kita A, Iwasaki Y, Sakai S, Okuto S, Takaoka K, Suzuki T, Yano S, Sawayama S, Tajima T, Kato J, Nishio N, Murakami K, Nakashimada Y. Development of genetic transformation and heterologous expression system in carboxydotrophic thermophilic acetogen Moorella thermoacetica. J Biosci Bioeng 2013. [DOI: 10.1016/j.jbiosc.2012.10.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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25
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Iwasaki Y, Kita A, Sakai S, Takaoka K, Yano S, Tajima T, Kato J, Nishio N, Murakami K, Nakashimada Y. Engineering of a functional thermostable kanamycin resistance marker for use in Moorella thermoacetica ATCC39073. FEMS Microbiol Lett 2013; 343:8-12. [PMID: 23448690 DOI: 10.1111/1574-6968.12113] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 02/20/2013] [Accepted: 02/21/2013] [Indexed: 11/29/2022] Open
Abstract
A transformation system for Moorella thermoacetica ATCC39073 was developed using thermostable kanamycin resistant gene (kanR) derived from the plasmid pJH1 that Streptococcus faecalis harbored. When kanR with its native promoter was introduced into uracil auxotrophic mutant of M. thermoacetica ATCC39073 together with a gene to complement the uracil auxotrophy as a selection marker, it did not give kanamycin resistance due to poor transcription level of kanR. However, the use of glyceraldehyde-3-phosphate dehydrogenase promoter cloned from M. thermoacetica ATCC39073 significantly improved transcription level of kanR and resulted in the cell growth in the presence of more than 150 μg mL(-1) kanamycin. It was also demonstrated that kanR with G3PD promoter can be used as a selection marker for transformation of wild-type strain of M. thermoacetica ATCC39073.
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Affiliation(s)
- Yuki Iwasaki
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Hiroshima, Japan
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26
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Isolation of thermophilic acetogens and transformation of them with the pyrF and kan(r) genes. Biosci Biotechnol Biochem 2013; 77:301-6. [PMID: 23391907 DOI: 10.1271/bbb.120720] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The application of microbial catalysts to syngas from the gasification of lignocellulosic biomass is gaining interest. Acetogens, a group of anaerobic bacteria, can grow autotrophically on gaseous substrates such as hydrogen and carbon dioxide or syngas and produce acetate via the acetyl-CoA pathway. Here, we report the isolation from a soil sample of two thermophilic acetogen strains, Y72 and Y73, that are closely related to Moorella sp. HUC22-1 and M. thermoacetica ATCC39073. The optimal growth temperature and pH for the strains were 60 °C and 6.0-6.5. Uracil auxotrophy was induced in them by replacing the orotate monophosphate decarboxylase gene (pyrF) with the kanamycin resistant marker (kan(r)). The transformants were isolated by supplementation of the basal medium with 300 mg/L of kanamycin. The transformation efficiency of strains Y72 and Y73 was 20-fold higher than that of strain ATCC39073. Hence these strains are considered possible hosts for thermophilic syngas fermentation.
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Hao LP, Lü F, Li L, Shao LM, He PJ. Shift of pathways during initiation of thermophilic methanogenesis at different initial pH. BIORESOURCE TECHNOLOGY 2012; 126:418-424. [PMID: 22227145 DOI: 10.1016/j.biortech.2011.12.072] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 12/12/2011] [Accepted: 12/13/2011] [Indexed: 05/31/2023]
Abstract
To investigate the metabolic pathways during the initiation of methanogenesis from acid crisis, the influence of initial pH (5.0-6.5) on thermophilic methanogenic conversion of 100mmol/L acetate was monitored based on the isotopic signature and selective-inhibition method combined with analysis of the microbial structure. The results showed, lower pH extended the lag phase for methanogenesis which was inhibited at pH5.0 throughout the incubation. At initial pH6.0-6.5, methanogenesis was primarily initiated via acetoclastic methanogenesis (AM), with the fraction of the hydrogenotrophic pathway (f(mc)) accounting for 21-22% of total methane formation. Conversely, at initial pH5.5, the dominant pathway shifted to syntrophic acetate oxidation coupled with hydrogenotrophic methanogenesis (SAO-HM), with f(mc) rising to 51% and the abundance of syntrophic acetate-oxidizing bacteria increasing remarkably. Methanogenesis could initiate independently via SAO-HM pathway when AM pathway was inhibited. Acetate-oxidizing syntrophs could function as the initiation center of methanogenesis from low-pH crisis.
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Affiliation(s)
- Li-Ping Hao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
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28
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Tirado-Acevedo O, Chinn MS, Grunden AM. Production of biofuels from synthesis gas using microbial catalysts. ADVANCES IN APPLIED MICROBIOLOGY 2010; 70:57-92. [PMID: 20359454 DOI: 10.1016/s0065-2164(10)70002-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
World energy consumption is expected to increase 44% in the next 20 years. Today, the main sources of energy are oil, coal, and natural gas, all fossil fuels. These fuels are unsustainable and contribute to environmental pollution. Biofuels are a promising source of sustainable energy. Feedstocks for biofuels used today such as grain starch are expensive and compete with food markets. Lignocellulosic biomass is abundant and readily available from a variety of sources, for example, energy crops and agricultural/industrial waste. Conversion of these materials to biofuels by microorganisms through direct hydrolysis and fermentation can be challenging. Alternatively, biomass can be converted to synthesis gas through gasification and transformed to fuels using chemical catalysts. Chemical conversion of synthesis gas components can be expensive and highly susceptible to catalyst poisoning, limiting biofuel yields. However, there are microorganisms that can convert the CO, H(2), and CO(2) in synthesis gas to fuels such as ethanol, butanol, and hydrogen. Biomass gasification-biosynthesis processing systems have shown promise as some companies have already been exploiting capable organisms for commercial purposes. The discovery of novel organisms capable of higher product yield, as well as metabolic engineering of existing microbial catalysts, makes this technology a viable option for reducing our dependency on fossil fuels.
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Affiliation(s)
- Oscar Tirado-Acevedo
- Department of Microbiology, North Carolina State University, Raleigh, North Carolina, USA
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Inokuma K, Nakashimada Y, Akahoshi T, Nishio N. Characterization of enzymes involved in the ethanol production of Moorella sp. HUC22-1. Arch Microbiol 2007; 188:37-45. [PMID: 17318639 DOI: 10.1007/s00203-007-0221-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2006] [Revised: 01/22/2007] [Accepted: 01/26/2007] [Indexed: 10/23/2022]
Abstract
Since the thermophilic bacterium Moorella sp. HUC22-1 produces 120 mM acetate and 5.2 mM ethanol from H(2)-CO(2), several candidate genes, which were predicted to code for three alcohol dehydrogenases (AdhA, B, C) and one acetaldehyde dehydrogenase (Aldh), were cloned from HUC22-1. The cloned genes were subcloned into a His-tagged expression vector and expressed in Escherichia coli. Recombinant AdhA and B were both dependent on NADP(H) but independent of NAD(H), and their reduction activities from aldehyde to alcohol were higher than their oxidation activities. In contrast with AdhA and B, no activity of AdhC was observed in either reaction. On the other hand, Aldh was active toward both NADP(H) and NAD(H). The enzyme activity of Aldh was directed toward the thioester cleavage and the thioester condensation. When 50 microg of AdhA and 50 microg Aldh were added to the buffer solution (pH 8.0) containing NADPH, NADH and acetyl-CoA at 60 degrees C, 1.6 mM ethanol was produced from 3 mM acetyl-CoA after 90 min. Expression analysis of the mRNAs revealed that the expression level of aldh was threefold higher in the H(2)-CO(2) culture than that in the fructose culture, but levels of adhA, B and C were decreased.
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Affiliation(s)
- Kentaro Inokuma
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8530, Japan
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