1
|
Cha M, Kim JK, Lee WH, Song H, Lee TG, Kim SK, Kim SJ. Metabolic engineering of Caldicellulosiruptor bescii for hydrogen production. Appl Microbiol Biotechnol 2024; 108:65. [PMID: 38194138 PMCID: PMC10776719 DOI: 10.1007/s00253-023-12974-7] [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: 10/07/2023] [Revised: 12/04/2023] [Accepted: 12/15/2023] [Indexed: 01/10/2024]
Abstract
Hydrogen is an alternative fuel for transportation vehicles because it is clean, sustainable, and highly flammable. However, the production of hydrogen from lignocellulosic biomass by microorganisms presents challenges. This microbial process involves multiple complex steps, including thermal, chemical, and mechanical treatment of biomass to remove hemicellulose and lignin, as well as enzymatic hydrolysis to solubilize the plant cell walls. These steps not only incur costs but also result in the production of toxic hydrolysates, which inhibit microbial growth. A hyper-thermophilic bacterium of Caldicellulosiruptor bescii can produce hydrogen by decomposing and fermenting plant biomass without the need for conventional pretreatment. It is considered as a consolidated bioprocessing (CBP) microorganism. This review summarizes the basic scientific knowledge and hydrogen-producing capacity of C. bescii. Its genetic system and metabolic engineering strategies to improve hydrogen production are also discussed. KEY POINTS: • Hydrogen is an alternative and eco-friendly fuel. • Caldicellulosiruptor bescii produces hydrogen with a high yield in nature. • Metabolic engineering can make C. bescii to improve hydrogen production.
Collapse
Affiliation(s)
- Minseok Cha
- Research Center for Biological Cybernetics, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Jung Kon Kim
- Department of Animal Environment, National Institute of Animal Science, Wanju, 55365, Republic of Korea
| | - Won-Heong Lee
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | | | - Tae-Gi Lee
- Department of Food Science and Biotechnology, Chung-Ang University, Gyeonggi, 17546, Republic of Korea
| | - Sun-Ki Kim
- Department of Food Science and Biotechnology, Chung-Ang University, Gyeonggi, 17546, Republic of Korea
| | - Soo-Jung Kim
- Research Center for Biological Cybernetics, Chonnam National University, Gwangju, 61186, Republic of Korea.
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju, 61186, Republic of Korea.
| |
Collapse
|
2
|
Cha M, Kim JH, Choi HJ, Nho SB, Kim SY, Cha YL, Song H, Lee WH, Kim SK, Kim SJ. Hydrogen Production from Barley Straw and Miscanthus by the Hyperthermophilic Bacterium, Cadicellulosirupter bescii. J Microbiol Biotechnol 2023; 33:1384-1389. [PMID: 37463861 PMCID: PMC10619549 DOI: 10.4014/jmb.2305.05022] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 07/20/2023]
Abstract
This work aimed to evaluate the feasibility of biohydrogen production from Barley Straw and Miscanthus. The primary obstacle in plant biomass decomposition is the recalcitrance of the biomass itself. Plant cell walls consist of cellulose, hemicellulose, and lignin, which make the plant robust to decomposition. However, the hyperthermophilic bacterium, Caldicellulosiruptor bescii, can efficiently utilize lignocellulosic feedstocks (Barley Straw and Miscanthus) for energy production, and C. bescii can now be metabolically engineered or isolated to produce more hydrogen and other biochemicals. In the present study, two strains, C. bescii JWCB001 (wild-type) and JWCB018 (ΔpyrFA Δldh ΔcbeI), were tested for their ability to increase hydrogen production from Barley Straw and Miscanthus. The JWCB018 resulted in a redirection of carbon and electron (carried by NADH) flow from lactate production to acetate and hydrogen production. JWCB018 produced ~54% and 63% more acetate and hydrogen from Barley Straw, respectively than its wild-type counterpart, JWCB001. Also, 25% more hydrogen from Miscanthus was obtained by the JWCB018 strain with 33% more acetate relative to JWCB001. It was supported that the engineered C. bescii, such as the JWCB018, can be a parental strain to get more hydrogen and other biochemicals from various biomass.
Collapse
Affiliation(s)
- Minseok Cha
- Research Center for Biological Cybernetics, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jun-Ha Kim
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Hyo-Jin Choi
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Soo Bin Nho
- Department of Food Science and Biotechnology, Chung-Ang University, Gyeonggi 17546, Republic of Korea
| | - Soo-Yeon Kim
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan 58545, Republic of Korea
| | - Young-Lok Cha
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan 58545, Republic of Korea
| | - Hyoungwoon Song
- Institute for Advanced Engineering, Gyeonggi 17180, Republic of Korea
| | - Won-Heong Lee
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Sun-Ki Kim
- Department of Food Science and Biotechnology, Chung-Ang University, Gyeonggi 17546, Republic of Korea
| | - Soo-Jung Kim
- Research Center for Biological Cybernetics, Chonnam National University, Gwangju 61186, Republic of Korea
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| |
Collapse
|
3
|
Truong C, Bernard S, Le Pape P, Morin G, Baya C, Merrot P, Gorlas A, Guyot F. Production of carbon-containing pyrite spherules induced by hyperthermophilic Thermococcales: a biosignature? Front Microbiol 2023; 14:1145781. [PMID: 37303784 PMCID: PMC10248028 DOI: 10.3389/fmicb.2023.1145781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Thermococcales, a major order of hyperthermophilic archaea inhabiting iron- and sulfur-rich anaerobic parts of hydrothermal deep-sea vents, are known to induce the formation of iron phosphates, greigite (Fe3S4) and abundant quantities of pyrite (FeS2), including pyrite spherules. In the present study, we report the characterization of the sulfide and phosphate minerals produced in the presence of Thermococcales using X-ray diffraction, synchrotron-based X ray absorption spectroscopy and scanning and transmission electron microscopies. Mixed valence Fe(II)-Fe(III) phosphates are interpreted as resulting from the activity of Thermococcales controlling phosphorus-iron-sulfur dynamics. The pyrite spherules (absent in abiotic control) consist of an assemblage of ultra-small nanocrystals of a few ten nanometers in size, showing coherently diffracting domain sizes of few nanometers. The production of these spherules occurs via a sulfur redox swing from S0 to S-2 and then to S-1, involving a comproportionation of (-II) and (0) oxidation states of sulfur, as supported by S-XANES data. Importantly, these pyrite spherules sequester biogenic organic compounds in small but detectable quantities, possibly making them good biosignatures to be searched for in extreme environments.
Collapse
Affiliation(s)
- Chloé Truong
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Sylvain Bernard
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Pierre Le Pape
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Guillaume Morin
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Camille Baya
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Pauline Merrot
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Aurore Gorlas
- CEA, CNRS, Institute for Integrative Biology of the Cell, Université Paris-Saclay, Gif-sur-Yvette, France
| | - François Guyot
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
- Institut Universitaire de France (IUF), Paris, France
| |
Collapse
|
4
|
Cao Y, Liu H, Liu W, Guo J, Xian M. Debottlenecking the biological hydrogen production pathway of dark fermentation: insight into the impact of strain improvement. Microb Cell Fact 2022; 21:166. [PMID: 35986320 PMCID: PMC9389701 DOI: 10.1186/s12934-022-01893-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 07/26/2022] [Indexed: 11/26/2022] Open
Abstract
Confronted with the exhaustion of the earth’s fossil fuel reservoirs, bio-based process to produce renewable energy is receiving significant interest. Hydrogen is considered as an attractive energy carrier that can replace fossil fuels in the future mainly due to its high energy content, recyclability and environment-friendly nature. Biological hydrogen production from renewable biomass or waste materials by dark fermentation is a promising alternative to conventional routes since it is energy-saving and reduces environmental pollution. However, the current yield and evolution rate of fermentative hydrogen production are still low. Strain improvement of the microorganisms employed for hydrogen production is required to make the process competitive with traditional production methods. The present review summarizes recent progresses on the screening for highly efficient hydrogen-producing strains using various strategies. As the metabolic pathways for fermentative hydrogen production have been largely resolved, it is now possible to engineer the hydrogen-producing strains by rational design. The hydrogen yields and production rates by different genetically modified microorganisms are discussed. The key limitations and challenges faced in present studies are also proposed. We hope that this review can provide useful information for scientists in the field of fermentative hydrogen production. Hydrogen can be generated by microorganisms. Dark fermentation is efficient for biological hydrogen production. Strain improvement is critical to enhancing hydrogen-producing ability.
Collapse
|
5
|
Gorlas A, Mariotte T, Morey L, Truong C, Bernard S, Guigner JM, Oberto J, Baudin F, Landrot G, Baya C, Le Pape P, Morin G, Forterre P, Guyot F. Precipitation of greigite and pyrite induced by Thermococcales: an advantage to live in Fe- and S-rich environments? Environ Microbiol 2022; 24:626-642. [PMID: 35102700 PMCID: PMC9306673 DOI: 10.1111/1462-2920.15915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/05/2022] [Accepted: 01/17/2022] [Indexed: 11/29/2022]
Abstract
Thermococcales, a major order of archaea inhabiting the iron- and sulfur-rich anaerobic parts of hydrothermal deep-sea vents, have been shown to rapidly produce abundant quantities of pyrite FeS2 in iron-sulfur-rich fluids at 85°C, suggesting that they may contribute to the formation of 'low temperature' FeS2 in their ecosystem. We show that this process operates in Thermococcus kodakarensis only when zero-valent sulfur is directly available as intracellular sulfur vesicles. Whether in the presence or absence of zero-valent sulfur, significant amounts of Fe3 S4 greigite nanocrystals are formed extracellularly. We also show that mineralization of iron sulfides induces massive cell mortality but that concomitantly with the formation of greigite and/or pyrite, a new generation of cells can grow. This phenomenon is observed for Fe concentrations of 5 mM but not higher suggesting that above a threshold in the iron pulse all cells are lysed. We hypothesize that iron sulfides precipitation on former cell materials might induce the release of nutrients in the mineralization medium further used by a fraction of surviving non-mineralized cells allowing production of new alive cells. This suggests that biologically induced mineralization of iron-sulfides could be part of a survival strategy employed by Thermococcales to cope with mineralizing high-temperature hydrothermal environments.
Collapse
Affiliation(s)
- A Gorlas
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, 91198, France
| | - T Mariotte
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, 91198, France
| | - L Morey
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, 91198, France
| | - C Truong
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 - CNRS, Sorbonne Université, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France
| | - S Bernard
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 - CNRS, Sorbonne Université, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France
| | - J-M Guigner
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 - CNRS, Sorbonne Université, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France
| | - J Oberto
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, 91198, France
| | - F Baudin
- Institut des Sciences de la Terre de Paris, UMR 7193 - Sorbonne Université - CNRS, Paris, 75005, France
| | - G Landrot
- Synchrotron SOLEIL - SAMBA beamline, Saint-Aubin, 91190, France
| | - C Baya
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 - CNRS, Sorbonne Université, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France
| | - P Le Pape
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 - CNRS, Sorbonne Université, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France
| | - G Morin
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 - CNRS, Sorbonne Université, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France
| | - P Forterre
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, 91198, France
| | - F Guyot
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 - CNRS, Sorbonne Université, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France.,Institut Universitaire de France (IUF), Paris, France
| |
Collapse
|
6
|
Liman GLS, Stettler ME, Santangelo TJ. Transformation Techniques for the Anaerobic Hyperthermophile Thermococcus kodakarensis. Methods Mol Biol 2022; 2522:87-104. [PMID: 36125744 PMCID: PMC10026556 DOI: 10.1007/978-1-0716-2445-6_5] [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] [Indexed: 10/14/2022]
Abstract
Genetic manipulation is an essential tool to investigate complex microbiological phenomena. In this chapter we describe the techniques required to transform the model hyperthermophilic, anaerobic archaeon Thermococcus kodakarensis. T. kodakarensis can support two modes of genetic manipulation, dependent either on homologous recombination into the genome or through retention of autonomously replicating plasmids. The robust genetic system developed in T. kodakarensis offers a variety of selectable and counterselectable markers for complex, accurate and iterative genetic manipulations offering greater flexibility to probe gene function in vivo.
Collapse
Affiliation(s)
- Geraldy L S Liman
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Meghan E Stettler
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Thomas J Santangelo
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA.
| |
Collapse
|
7
|
Pfeifer K, Ergal İ, Koller M, Basen M, Schuster B, Rittmann SKMR. Archaea Biotechnology. Biotechnol Adv 2020; 47:107668. [PMID: 33271237 DOI: 10.1016/j.biotechadv.2020.107668] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 11/19/2020] [Accepted: 11/20/2020] [Indexed: 12/13/2022]
Abstract
Archaea are a domain of prokaryotic organisms with intriguing physiological characteristics and ecological importance. In Microbial Biotechnology, archaea are historically overshadowed by bacteria and eukaryotes in terms of public awareness, industrial application, and scientific studies, although their biochemical and physiological properties show a vast potential for a wide range of biotechnological applications. Today, the majority of microbial cell factories utilized for the production of value-added and high value compounds on an industrial scale are bacterial, fungal or algae based. Nevertheless, archaea are becoming ever more relevant for biotechnology as their cultivation and genetic systems improve. Some of the main advantages of archaeal cell factories are the ability to cultivate many of these often extremophilic organisms under non-sterile conditions, and to utilize inexpensive feedstocks often toxic to other microorganisms, thus drastically reducing cultivation costs. Currently, the only commercially available products of archaeal cell factories are bacterioruberin, squalene, bacteriorhodopsin and diether-/tetraether-lipids, all of which are produced utilizing halophiles. Other archaeal products, such as carotenoids and biohydrogen, as well as polyhydroxyalkanoates and methane are in early to advanced development stages, respectively. The aim of this review is to provide an overview of the current state of Archaea Biotechnology by describing the actual state of research and development as well as the industrial utilization of archaeal cell factories, their role and their potential in the future of sustainable bioprocessing, and to illustrate their physiological and biotechnological potential.
Collapse
Affiliation(s)
- Kevin Pfeifer
- Archaea Physiology & Biotechnology Group, Department of Functional and Evolutionary Ecology, Universität Wien, Wien, Austria; Institute of Synthetic Bioarchitectures, Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Wien, Austria
| | - İpek Ergal
- Archaea Physiology & Biotechnology Group, Department of Functional and Evolutionary Ecology, Universität Wien, Wien, Austria
| | - Martin Koller
- Office of Research Management and Service, c/o Institute of Chemistry, University of Graz, Austria
| | - Mirko Basen
- Microbial Physiology Group, Division of Microbiology, Institute of Biological Sciences, University of Rostock, Rostock, Germany
| | - Bernhard Schuster
- Institute of Synthetic Bioarchitectures, Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Wien, Austria
| | - Simon K-M R Rittmann
- Archaea Physiology & Biotechnology Group, Department of Functional and Evolutionary Ecology, Universität Wien, Wien, Austria.
| |
Collapse
|
8
|
Rao R, Basak N. Development of novel strategies for higher fermentative biohydrogen recovery along with novel metabolites from organic wastes: The present state of the art. Biotechnol Appl Biochem 2020; 68:421-444. [PMID: 32474946 DOI: 10.1002/bab.1964] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Accepted: 05/30/2020] [Indexed: 01/15/2023]
Abstract
Depletion of fossil fuels and environmental concern has compelled us to search for alternative fuel. Hydrogen is considered as a dream fuel as it has high energy content (142 kJ g-1 ) and is not chemically bound to carbon. At present, fossil fuel-based methods for producing hydrogen require high-energy input, which makes the processes expensive. The major processes for biohydrogen production are biophotolysis, microbial electrolysis, dark fermentation, and photofermentation. Fermentative hydrogen production has the additional advantages of potentially using various waste streams from different industries as feedstock. Novel strategies to enhance the productivity of fermentative hydrogen production include optimization in pretreatment methods, integrated fermentation systems (sequential and combined fermentation), use of nanoparticles as additives, metabolic engineering of microorganisms, improving the light utilization efficiency, developing more efficient photobioreactors, etc. More focus has been given to produce biohydrogen in a biorefinery approach in which, along with hydrogen gas, other metabolites (ethanol, butyric acid, 1,3-propanediol, etc.) are also produced, which have direct/indirect industrial applications. In present review, various emerging technologies that highlight biohydrogen production methods as effective and sustainable methods on a large scale have been critically reviewed. The possible future developments are also outlined.
Collapse
Affiliation(s)
- Raman Rao
- Department of Biotechnology, Dr. B. R Ambedkar National Institute of Technology, Jalandhar, 144 011, India
| | - Nitai Basak
- Department of Biotechnology, Dr. B. R Ambedkar National Institute of Technology, Jalandhar, 144 011, India
| |
Collapse
|
9
|
Simons JR, Beppu H, Imanaka T, Kanai T, Atomi H. Effects of high-level expression of A 1-ATPase on H 2 production in Thermococcus kodakarensis. J Biosci Bioeng 2020; 130:149-158. [PMID: 32414665 DOI: 10.1016/j.jbiosc.2020.04.001] [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: 01/11/2020] [Revised: 03/18/2020] [Accepted: 04/01/2020] [Indexed: 10/24/2022]
Abstract
The hyperthermophilic archaeon Thermococcus kodakarensis can grow on pyruvate or maltooligosaccharides through H2 fermentation. H2 production levels of members of the Thermococcales are high, and studies to improve their production potential have been reported. Although H2 production is primary metabolism, here we aimed to partially uncouple cell growth and H2 production of T. kodakarensis. Additional A1-type ATPase genes were introduced into T. kodakarensis KU216 under the control of two promoters; the strong constitutive cell surface glycoprotein promoter, Pcsg, and the sugar-inducible fructose-1,6-bisphosphate aldolase promoter, Pfba. Whereas cells with the A1-type ATPase genes under the control of Pcsg displayed only trace levels of growth, cells with Pfba (strain KUA-PF) displayed growth sufficient for further analysis. Increased levels of A1-type ATPase protein were detected in KUA-PF cells grown on pyruvate or maltodextrin, when compared to the levels in the host strain KU216. The growth and H2 production levels of strain KUA-PF with pyruvate or maltodextrin as a carbon and electron source were analyzed and compared to those of the host strain KU216. Compared to a small decrease in total H2 production, significantly larger decreases in cell growth were observed, resulting in an increase in cell-specific H2 production. Quantification of the substrate also revealed that ATPase overexpression led to increased cell-specific pyruvate and maltodextrin consumptions. The results clearly indicate that ATPase production results in partial uncoupling of cell growth and H2 production in T. kodakarensis.
Collapse
Affiliation(s)
- Jan-Robert Simons
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Haruki Beppu
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Tadayuki Imanaka
- Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu 525-8577, Japan
| | - Tamotsu Kanai
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Haruyuki Atomi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
| |
Collapse
|
10
|
Kumar S, Sharma S, Thakur S, Mishra T, Negi P, Mishra S, Hesham AEL, Rastegari AA, Yadav N, Yadav AN. Bioprospecting of Microbes for Biohydrogen Production: Current Status and Future Challenges. BIOPROCESSING FOR BIOMOLECULES PRODUCTION 2019:443-471. [DOI: 10.1002/9781119434436.ch22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Affiliation(s)
| | | | | | | | | | | | - Abd El-Latif Hesham
- Genetics Department, Faculty of Agriculture; Assiut University; Assiut Egypt
| | - Ali A. Rastegari
- Department of Molecular and Cell Biochemistry, Falavarjan Branch; Islamic Azad University; Isfahan Iran
| | - Neelam Yadav
- Gopi Nath P.G. College; Veer Bahadur Singh Purvanchal University; India
| | | |
Collapse
|
11
|
Jay ZJ, Hunt KA, Chou KJ, Schut GJ, Maness PC, Adams MWW, Carlson RP. Integrated thermodynamic analysis of electron bifurcating [FeFe]-hydrogenase to inform anaerobic metabolism and H 2 production. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1861:148087. [PMID: 31669490 DOI: 10.1016/j.bbabio.2019.148087] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 09/14/2019] [Accepted: 10/18/2019] [Indexed: 12/27/2022]
Abstract
Electron bifurcating, [FeFe]-hydrogenases are recently described members of the hydrogenase family and catalyze a combination of exergonic and endergonic electron exchanges between three carriers (2 ferredoxinred- + NAD(P)H + 3 H+ = 2 ferredoxinox + NAD(P)+ + 2 H2). A thermodynamic analysis of the bifurcating, [FeFe]-hydrogenase reaction, using electron path-independent variables, quantified potential biological roles of the reaction without requiring enzyme details. The bifurcating [FeFe]-hydrogenase reaction, like all bifurcating reactions, can be written as a sum of two non-bifurcating reactions. Therefore, the thermodynamic properties of the bifurcating reaction can never exceed the properties of the individual, non-bifurcating, reactions. The bifurcating [FeFe]-hydrogenase reaction has three competitive properties: 1) enabling NAD(P)H-driven proton reduction at pH2 higher than the concurrent operation of the two, non-bifurcating reactions, 2) oxidation of NAD(P)H and ferredoxin simultaneously in a 1:1 ratio, both are produced during typical glucose fermentations, and 3) enhanced energy conservation (~10 kJ mol-1 H2) relative to concurrent operation of the two, non-bifurcating reactions. Our analysis demonstrated ferredoxin E°' largely determines the sensitivity of the bifurcating reaction to pH2, modulation of the reduced/oxidized electron carrier ratios contributed less to equilibria shifts. Hydrogenase thermodynamics data were integrated with typical and non-typical glycolysis pathways to evaluate achieving the 'Thauer limit' (4 H2 per glucose) as a function of temperature and pH2. For instance, the bifurcating [FeFe]-hydrogenase reaction permits the Thauer limit at 60 °C if pH 2 ≤ ~10 mbar. The results also predict Archaea, expressing a non-typical glycolysis pathway, would not benefit from a bifurcating [FeFe]-hydrogenase reaction; interestingly, no Archaea have been observed experimentally with a [FeFe]-hydrogenase enzyme.
Collapse
Affiliation(s)
- Zackary J Jay
- Department of Chemical and Biological Engineering, Center for Biofilm Engineering,Thermal Biology Institute, Montana State University, Bozeman, MT 59717, USA
| | - Kristopher A Hunt
- Department of Chemical and Biological Engineering, Center for Biofilm Engineering,Thermal Biology Institute, Montana State University, Bozeman, MT 59717, USA
| | - Katherine J Chou
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Gerrit J Schut
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Pin-Ching Maness
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Ross P Carlson
- Department of Chemical and Biological Engineering, Center for Biofilm Engineering,Thermal Biology Institute, Montana State University, Bozeman, MT 59717, USA.
| |
Collapse
|
12
|
Extreme thermophiles as emerging metabolic engineering platforms. Curr Opin Biotechnol 2019; 59:55-64. [DOI: 10.1016/j.copbio.2019.02.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/31/2019] [Accepted: 02/09/2019] [Indexed: 02/06/2023]
|
13
|
Orita I, Futatsuishi R, Adachi K, Ohira T, Kaneko A, Minowa K, Suzuki M, Tamura T, Nakamura S, Imanaka T, Suzuki T, Fukui T. Random mutagenesis of a hyperthermophilic archaeon identified tRNA modifications associated with cellular hyperthermotolerance. Nucleic Acids Res 2019; 47:1964-1976. [PMID: 30605516 PMCID: PMC6393311 DOI: 10.1093/nar/gky1313] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 12/05/2018] [Accepted: 12/22/2018] [Indexed: 12/20/2022] Open
Abstract
Random mutagenesis for the hyperthermophilic archaeon Thermococcus kodakarensis was established by the insertion of an artificial transposon designed to allow easy identification of the transposon-inserted locus. The phenotypic screening was applied for the isolation of thermosensitive mutants of T. kodakarensis, which resulted in the isolation of 16 mutants showing defective growth at the supraoptimal temperature 93°C. The high occurrence of the mutants suggested that the high thermotolerance of hyperthermophiles was achieved by a combination of diverse gene functions. The transposon insertion sites in two-thirds of the mutants were identified in a group of genes responsible for tRNA modifications including 7-formamidino-7-deaza-guanosine (archaeosine), N1-methyladenosine/N1-methylinosine, N4-acetylcytidine, and N2-dimethylguanosine/N2,N2-dimethylguanosine. LC–MS/MS analyses of tRNA nucleosides and fragments exhibited disappearance of the corresponding modifications in the mutants. The melting temperature of total tRNA fraction isolated from the mutants lacking archaeosine or N1-methyladenosine/N1-methylinosine decreased significantly, suggesting that the thermosensitive phenotype of these mutants was attributed to low stability of the hypomodified tRNAs. Genes for metabolism, transporters, and hypothetical proteins were also identified in the thermosensitive mutants. The present results demonstrated the usefulness of random mutagenesis for the studies on the hyperthermophile, as well as crucial roles of tRNA modifications in cellular thermotolerance.
Collapse
Affiliation(s)
- Izumi Orita
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| | - Ryohei Futatsuishi
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| | - Kyoko Adachi
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| | - Takayuki Ohira
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Akira Kaneko
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| | - Keiichi Minowa
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Miho Suzuki
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| | - Takeshi Tamura
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| | - Satoshi Nakamura
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| | - Tadayuki Imanaka
- Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu 525-8577, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Toshiaki Fukui
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan
| |
Collapse
|
14
|
An overview of 25 years of research on Thermococcus kodakarensis, a genetically versatile model organism for archaeal research. Folia Microbiol (Praha) 2019; 65:67-78. [PMID: 31286382 DOI: 10.1007/s12223-019-00730-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 06/17/2019] [Indexed: 10/26/2022]
Abstract
Almost 25 years have passed since the discovery of a planktonic, heterotrophic, hyperthermophilic archaeon named Thermococcus kodakarensis KOD1, previously known as Pyrococcus sp. KOD1, by Imanaka and coworkers. T. kodakarensis is one of the most studied archaeon in terms of metabolic pathways, available genomic resources, established genetic engineering techniques, reporter constructs, in vitro transcription/translation machinery, and gene expression/gene knockout systems. In addition to all these, ease of growth using various carbon sources makes it a facile archaeal model organism. Here, in this review, an attempt is made to reflect what we have learnt from this hyperthermophilic archaeon.
Collapse
|
15
|
Distinct Physiological Roles of the Three Ferredoxins Encoded in the Hyperthermophilic Archaeon Thermococcus kodakarensis. mBio 2019; 10:mBio.02807-18. [PMID: 30837343 PMCID: PMC6401487 DOI: 10.1128/mbio.02807-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
High-energy electrons liberated during catabolic processes can be exploited for energy-conserving mechanisms. Maximal energy gains demand these valuable electrons be accurately shuttled from electron donor to appropriate electron acceptor. Proteinaceous electron carriers such as ferredoxins offer opportunities to exploit specific ferredoxin partnerships to ensure that electron flux to critical physiological pathways is aligned with maximal energy gains. Most species encode many ferredoxin isoforms, but very little is known about the role of individual ferredoxins in most systems. Our results detail that ferredoxin isoforms make largely unique and distinct protein interactions in vivo and that flux through one ferredoxin often cannot be recovered by flux through a different ferredoxin isoform. The results obtained more broadly suggest that ferredoxin isoforms throughout biological life have evolved not as generic electron shuttles, but rather serve as selective couriers of valuable low-potential electrons from select electron donors to desirable electron acceptors. Control of electron flux is critical in both natural and bioengineered systems to maximize energy gains. Both small molecules and proteins shuttle high-energy, low-potential electrons liberated during catabolism through diverse metabolic landscapes. Ferredoxin (Fd) proteins—an abundant class of Fe-S-containing small proteins—are essential in many species for energy conservation and ATP production strategies. It remains difficult to model electron flow through complicated metabolisms and in systems in which multiple Fd proteins are present. The overlap of activity and/or limitations of electron flux through each Fd can limit physiology and metabolic engineering strategies. Here we establish the interplay, reactivity, and physiological role(s) of the three ferredoxin proteins in the model hyperthermophile Thermococcus kodakarensis. We demonstrate that the three loci encoding known Fds are subject to distinct regulatory mechanisms and that specific Fds are utilized to shuttle electrons to separate respiratory and energy production complexes during different physiological states. The results obtained argue that unique physiological roles have been established for each Fd and that continued use of T. kodakarensis and related hydrogen-evolving species as bioengineering platforms must account for the distinct Fd partnerships that limit flux to desired electron acceptors. Extrapolating our results more broadly, the retention of multiple Fd isoforms in most species argues that specialized Fd partnerships are likely to influence electron flux throughout biology.
Collapse
|
16
|
Straub CT, Counts JA, Nguyen DMN, Wu CH, Zeldes BM, Crosby JR, Conway JM, Otten JK, Lipscomb GL, Schut GJ, Adams MWW, Kelly RM. Biotechnology of extremely thermophilic archaea. FEMS Microbiol Rev 2018; 42:543-578. [PMID: 29945179 DOI: 10.1093/femsre/fuy012] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Accepted: 06/23/2018] [Indexed: 12/26/2022] Open
Abstract
Although the extremely thermophilic archaea (Topt ≥ 70°C) may be the most primitive extant forms of life, they have been studied to a limited extent relative to mesophilic microorganisms. Many of these organisms have unique biochemical and physiological characteristics with important biotechnological implications. These include methanogens that generate methane, fermentative anaerobes that produce hydrogen gas with high efficiency, and acidophiles that can mobilize base, precious and strategic metals from mineral ores. Extremely thermophilic archaea have also been a valuable source of thermoactive, thermostable biocatalysts, but their use as cellular systems has been limited because of the general lack of facile genetics tools. This situation has changed recently, however, thereby providing an important avenue for understanding their metabolic and physiological details and also opening up opportunities for metabolic engineering efforts. Along these lines, extremely thermophilic archaea have recently been engineered to produce a variety of alcohols and industrial chemicals, in some cases incorporating CO2 into the final product. There are barriers and challenges to these organisms reaching their full potential as industrial microorganisms but, if these can be overcome, a new dimension for biotechnology will be forthcoming that strategically exploits biology at high temperatures.
Collapse
Affiliation(s)
- Christopher T Straub
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - James A Counts
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Diep M N Nguyen
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Chang-Hao Wu
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Benjamin M Zeldes
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - James R Crosby
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Jonathan M Conway
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Jonathan K Otten
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Gina L Lipscomb
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Gerrit J Schut
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| |
Collapse
|
17
|
The physiology and biotechnology of dark fermentative biohydrogen production. Biotechnol Adv 2018; 36:2165-2186. [DOI: 10.1016/j.biotechadv.2018.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/31/2018] [Accepted: 10/08/2018] [Indexed: 02/02/2023]
|
18
|
Topçuoğlu BD, Meydan C, Orellana R, Holden JF. Formate hydrogenlyase and formate secretion ameliorate H
2
inhibition in the hyperthermophilic archaeon
Thermococcus paralvinellae. Environ Microbiol 2017; 20:949-957. [DOI: 10.1111/1462-2920.14022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 11/06/2017] [Accepted: 11/06/2017] [Indexed: 11/26/2022]
Affiliation(s)
- Begüm D. Topçuoğlu
- Department of MicrobiologyUniversity of MassachusettsAmherst MA 01003 USA
| | - Cem Meydan
- Institute for Computational Biomedicine, Weill Cornell Medical CollegeNew York NY 10021 USA
| | - Roberto Orellana
- Centro de Biotecnología, Universidad Técnica Federico Santa MaríaValparaíso Chile
| | - James F. Holden
- Department of MicrobiologyUniversity of MassachusettsAmherst MA 01003 USA
| |
Collapse
|
19
|
Engineering of the Hyperthermophilic Archaeon Thermococcus kodakarensis for Chitin-Dependent Hydrogen Production. Appl Environ Microbiol 2017; 83:AEM.00280-17. [PMID: 28550062 DOI: 10.1128/aem.00280-17] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 05/16/2017] [Indexed: 11/20/2022] Open
Abstract
Thermococcus kodakarensis is a hyperthermophilic archaeon that harbors a complete set of genes for chitin degradation to fructose 6-phosphate. However, wild-type T. kodakarensis KOD1 does not display growth on chitin. In this study, we developed a T. kodakarensis strain that can grow on chitin via genetic and adaptive engineering. First, a chitinase overproduction strain (KC01) was constructed by replacing the chitinase gene promoter with a strong promoter from the cell surface glycoprotein gene, resulting in increased degradation of swollen chitin and accumulation of N-,N'-diacetylchitobiose in the medium. To enhance N-,N'-diacetylchitobiose assimilation in KC01, genes encoding diacetylchitobiose deacetylase, exo-β-d-glucosaminidase, and glucosamine-6-phosphate deaminase were also overexpressed to obtain strain KC04. To strengthen the glycolytic flux of KC04, the gene encoding Tgr (transcriptional repressor of glycolytic genes) was disrupted to obtain strain KC04Δt. In both KC04 and KC04Δt strains, degradation of swollen chitin was further enhanced. In the culture broth of these strains, the accumulation of glucosamine was observed. KC04Δt was repeatedly inoculated in a swollen-chitin-containing medium for 13 cultures. This adaptive engineering strategy resulted in the isolation of a strain (KC04ΔtM1) that showed almost complete degradation of 0.4% (wt/vol) swollen chitin after 90 h. The strain produced high levels of acetate and ammonium in the culture medium, and, moreover, molecular hydrogen was generated. This strongly suggests that strain KC04ΔtM1 has acquired the ability to convert chitin to fructose 6-phosphate via deacetylation and deamination and further convert fructose 6-phosphate to acetate via glycolysis coupled to hydrogen generation.IMPORTANCE Chitin is a linear homopolymer of β-1,4-linked N-acetylglucosamine and is the second most abundant biomass next to cellulose. Compared to the wealth of research focused on the microbial degradation and conversion of cellulose, studies addressing microbial chitin utilization are still limited. In this study, using the hyperthermophilic archaeon Thermococcus kodakarensis as a host, we have constructed a strain that displays chitin-dependent hydrogen generation. The apparent hydrogen yield per unit of sugar consumed was slightly higher with swollen chitin than with starch. As gene manipulation in T. kodakarensis is relatively simple, the strain constructed in this study can also be used as a parent strain for the development and expansion of chitin-dependent biorefinery, in addition to its capacity to produce hydrogen.
Collapse
|
20
|
Gavilà L, Güell EJ, Maru BT, Medina F, Constantí M. Combining catalytical and biological processes to transform cellulose into high value-added products. PHYSICAL SCIENCES REVIEWS 2017. [DOI: 10.1515/psr-2017-0026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractCellulose, the most abundant polymer of biomass, has an enormous potential as a source of chemicals and energy. However, its nature does not facilitate its exploitation in industry. As an entry point, here, two different strategies to hydrolyse cellulose are proposed. A solid and a liquid acid catalysts are tested. As a solid acid catalyst, zirconia and different zirconia-doped materials are proved, meanwhile liquid acid catalyst is carried out by sulfuric acid. Sulfuric acid proved to hydrolyse 78% of cellulose, while zirconia doped with sulfur converted 22% of cellulose. Both hydrolysates were used for fermentation with different microbial strains depending on the desired product: Citrobacter freundii H3 and Lactobacillus delbrueckii, for H
Collapse
|
21
|
Sharma A, Arya SK. Hydrogen from algal biomass: A review of production process. ACTA ACUST UNITED AC 2017; 15:63-69. [PMID: 28702371 PMCID: PMC5491395 DOI: 10.1016/j.btre.2017.06.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 05/20/2017] [Accepted: 06/01/2017] [Indexed: 11/24/2022]
Abstract
Biohydrogen Production Processes. Microorganisms involved in biohydrogen production processes. Immobilization methods of microalgae. Bioreactors for biohydrogen production process.
Multifariousness of biofuel sources has marked an edge to an imperative energy issue. Production of hydrogen from microalgae has been gathering much contemplation right away. But, mercantile production of microalgae biofuels considering bio-hydrogen is still not practicable because of low biomass concentration and costly down streaming processes. This review has taken up the hydrogen production by microalgae. Biofuels are the up and coming alternative to exhaustible, environmentally and unsafe fossil fuels. Algal biomass has been considered as an enticing raw material for biofuel production, these days photobioreactors and open-air systems are being used for hydrogen production from algal biomass. The formers allow the careful cultivation control whereas the latter ones are cheaper and simpler. A contemporary, encouraging optimization access has been included called algal cell immobilization on various matrixes which has resulted in marked increase in the productivity per volume of a reactor and addition of the hydrogen-production phase.
Collapse
Affiliation(s)
- Archita Sharma
- Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, India
| | - Shailendra Kumar Arya
- Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, India
| |
Collapse
|
22
|
Genetic analyses of the functions of [NiFe]-hydrogenase maturation endopeptidases in the hyperthermophilic archaeon Thermococcus kodakarensis. Extremophiles 2016; 21:27-39. [DOI: 10.1007/s00792-016-0875-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/24/2016] [Indexed: 10/20/2022]
|
23
|
Hensley SA, Moreira E, Holden JF. Hydrogen Production and Enzyme Activities in the Hyperthermophile Thermococcus paralvinellae Grown on Maltose, Tryptone, and Agricultural Waste. Front Microbiol 2016; 7:167. [PMID: 26941713 PMCID: PMC4762990 DOI: 10.3389/fmicb.2016.00167] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 02/01/2016] [Indexed: 02/03/2023] Open
Abstract
Thermococcus may be an important alternative source of H2 in the hot subseafloor in otherwise low H2 environments such as some hydrothermal vents and oil reservoirs. It may also be useful in industry for rapid agricultural waste treatment and concomitant H2 production. Thermococcus paralvinellae grown at 82°C without sulfur produced up to 5 mmol of H2 L(-1) at rates of 5-36 fmol H2 cell(-1) h(-1) on 0.5% (wt vol(-1)) maltose, 0.5% (wt vol(-1)) tryptone, and 0.5% maltose + 0.05% tryptone media. Two potentially inhibiting conditions, the presence of 10 mM acetate and low pH (pH 5) in maltose-only medium, did not significantly affect growth or H2 production. Growth rates, H2 production rates, and cell yields based on H2 production were the same as those for Pyrococcus furiosus grown at 95°C on the same media for comparison. Acetate, butyrate, succinate, isovalerate, and formate were also detected as end products. After 100 h, T. paralvinellae produced up to 5 mmol of H2 L(-1) of medium when grown on up to 70% (vol vol(-1)) waste milk from cows undergoing treatment for mastitis with the bacterial antibiotic Ceftiofur and from untreated cows. The amount of H2 produced by T. paralvinellae increased with increasing waste concentrations, but decreased in P. furiosus cultures supplemented with waste milk above 1% concentration. All mesophilic bacteria from the waste milk that grew on Luria Bertani, Sheep's Blood (selective for Staphylococcus, the typical cause of mastitis), and MacConkey (selective for Gram-negative enteric bacteria) agar plates were killed by heat during incubation at 82°C. Ceftiofur, which is heat labile, was below the detection limit following incubation at 82°C. T. paralvinellae also produced up to 6 mmol of H2 L(-1) of medium when grown on 0.1-10% (wt vol(-1)) spent brewery grain while P. furiosus produced < 1 mmol of H2 L(-1). Twelve of 13 enzyme activities in T. paralvinellae showed significant (p < 0.05) differences across six different growth conditions; however, methyl viologen-dependent membrane hydrogenase activity remained constant across all media types. The results demonstrate the potential of at least some Thermococcus species to produce H2 if protein and α-glucosides are present as substrates.
Collapse
Affiliation(s)
| | | | - James F. Holden
- Department of Microbiology, University of Massachusetts AmherstAmherst, MA, USA
| |
Collapse
|
24
|
Deletion of a gene cluster for [Ni-Fe] hydrogenase maturation in the anaerobic hyperthermophilic bacterium Caldicellulosiruptor bescii identifies its role in hydrogen metabolism. Appl Microbiol Biotechnol 2015; 100:1823-1831. [PMID: 26536872 DOI: 10.1007/s00253-015-7025-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/13/2015] [Accepted: 09/20/2015] [Indexed: 12/18/2022]
Abstract
The anaerobic, hyperthermophlic, cellulolytic bacterium Caldicellulosiruptor bescii grows optimally at ∼80 °C and effectively degrades plant biomass without conventional pretreatment. It utilizes a variety of carbohydrate carbon sources, including both C5 and C6 sugars, released from plant biomass and produces lactate, acetate, CO2, and H2 as primary fermentation products. The C. bescii genome encodes two hydrogenases, a bifurcating [Fe-Fe] hydrogenase and a [Ni-Fe] hydrogenase. The [Ni-Fe] hydrogenase is the most widely distributed in nature and is predicted to catalyze hydrogen production and to pump protons across the cellular membrane creating proton motive force. Hydrogenases are the key enzymes in hydrogen metabolism and their crystal structure reveals complexity in the organization of their prosthetic groups suggesting extensive maturation of the primary protein. Here, we report the deletion of a cluster of genes, hypABFCDE, required for maturation of the [Ni-Fe] hydrogenase. These proteins are specific for the hydrogenases they modify and are required for hydrogenase activity. The deletion strain grew more slowly than the wild type or the parent strain and produced slightly less hydrogen overall, but more hydrogen per mole of cellobiose. Acetate yield per mole of cellobiose was increased ∼67 % and ethanol yield per mole of cellobiose was decreased ∼39 %. These data suggest that the primary role of the [Ni-Fe] hydrogenase is to generate a proton gradient in the membrane driving ATP synthesis and is not the primary enzyme for hydrogen catalysis. In its absence, ATP is generated from increased acetate production resulting in more hydrogen produced per mole of cellobiose.
Collapse
|
25
|
Güell E, Maru B, Chimentão R, Gispert-Guirado F, Constantí M, Medina F. Combined heterogeneous catalysis and dark fermentation systems for the conversion of cellulose into biohydrogen. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2015.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
26
|
Kanai T, Simons JR, Tsukamoto R, Nakajima A, Omori Y, Matsuoka R, Beppu H, Imanaka T, Atomi H. Overproduction of the membrane-bound [NiFe]-hydrogenase in Thermococcus kodakarensis and its effect on hydrogen production. Front Microbiol 2015; 6:847. [PMID: 26379632 PMCID: PMC4549637 DOI: 10.3389/fmicb.2015.00847] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 08/03/2015] [Indexed: 12/29/2022] Open
Abstract
The hyperthermophilic archaeon Thermococcus kodakarensis can utilize sugars or pyruvate for growth. In the absence of elemental sulfur, the electrons via oxidation of these substrates are accepted by protons, generating molecular hydrogen (H2). The hydrogenase responsible for this reaction is a membrane-bound [NiFe]-hydrogenase (Mbh). In this study, we have examined several possibilities to increase the protein levels of Mbh in T. kodakarensis by genetic engineering. Highest levels of intracellular Mbh levels were achieved when the promoter of the entire mbh operon (TK2080-TK2093) was exchanged to a strong constitutive promoter from the glutamate dehydrogenase gene (TK1431) (strain MHG1). When MHG1 was cultivated under continuous culture conditions using pyruvate-based medium, a nearly 25% higher specific hydrogen production rate (SHPR) of 35.3 mmol H2 g-dcw−1 h−1 was observed at a dilution rate of 0.31 h−1. We also combined mbh overexpression using an even stronger constitutive promoter from the cell surface glycoprotein gene (TK0895) with disruption of the genes encoding the cytosolic hydrogenase (Hyh) and an alanine aminotransferase (AlaAT), both of which are involved in hydrogen consumption (strain MAH1). At a dilution rate of 0.30 h−1, the SHPR was 36.2 mmol H2 g-dcw−1 h−1, corresponding to a 28% increase compared to that of the host T. kodakarensis strain. Increasing the dilution rate to 0.83 h−1 or 1.07 h−1 resulted in a SHPR of 120 mmol H2 g-dcw−1 h−1, which is one of the highest production rates observed in microbial fermentation.
Collapse
Affiliation(s)
- Tamotsu Kanai
- Laboratory of Biochemical Engineering, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Kyoto, Japan ; Japan Science and Technology Agency, Core Research of Evolutional Science and Technology Tokyo, Japan
| | - Jan-Robert Simons
- Laboratory of Biochemical Engineering, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Kyoto, Japan ; Japan Science and Technology Agency, Core Research of Evolutional Science and Technology Tokyo, Japan
| | - Ryohei Tsukamoto
- Laboratory of Biochemical Engineering, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Kyoto, Japan
| | | | | | - Ryoji Matsuoka
- Laboratory of Biochemical Engineering, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Kyoto, Japan
| | - Haruki Beppu
- Laboratory of Biochemical Engineering, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Kyoto, Japan
| | - Tadayuki Imanaka
- Japan Science and Technology Agency, Core Research of Evolutional Science and Technology Tokyo, Japan ; Research Organization of Science and Technology, Ritsumeikan University Kusatsu, Japan
| | - Haruyuki Atomi
- Laboratory of Biochemical Engineering, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Kyoto, Japan ; Japan Science and Technology Agency, Core Research of Evolutional Science and Technology Tokyo, Japan
| |
Collapse
|
27
|
Rittmann SKM, Lee HS, Lim JK, Kim TW, Lee JH, Kang SG. One-carbon substrate-based biohydrogen production: Microbes, mechanism, and productivity. Biotechnol Adv 2015; 33:165-177. [DOI: 10.1016/j.biotechadv.2014.11.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 10/10/2014] [Accepted: 11/11/2014] [Indexed: 11/28/2022]
|
28
|
Genetic examination and mass balance analysis of pyruvate/amino acid oxidation pathways in the hyperthermophilic archaeon Thermococcus kodakarensis. J Bacteriol 2014; 196:3831-9. [PMID: 25157082 DOI: 10.1128/jb.02021-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The present study investigated the simultaneous oxidation of pyruvate and amino acids during H2-evolving growth of the hyperthermophilic archaeon Thermococcus kodakarensis. The comparison of mass balance between a cytosolic hydrogenase (HYH)-deficient strain (the ΔhyhBGSL strain) and the parent strain indicated that NADPH generated via H2 uptake by HYH was consumed by reductive amination of 2-oxoglutarate catalyzed by glutamate dehydrogenase. Further examinations were done to elucidate functions of three enzymes potentially involved in pyruvate oxidation: pyruvate formate-lyase (PFL), pyruvate:ferredoxin oxidoreductase (POR), and 2-oxoisovalerate:ferredoxin oxidoreductase (VOR) under the HYH-deficient background in T. kodakarensis. No significant change was observed by deletion of pflDA, suggesting that PFL had no critical role in pyruvate oxidation. The growth properties and mass balances of ΔporDAB and ΔvorDAB strains indicated that POR and VOR specifically functioned in oxidation of pyruvate and branched-chain amino acids, respectively, and the lack of POR or VOR was compensated for by promoting the oxidation of another substrate driven by the remaining oxidoreductase. The H2 yields from the consumed pyruvate and amino acids were increased from 31% by the parent strain to 67% and 82% by the deletion of hyhBGSL and double deletion of hyhBGSL and vorDAB, respectively. Significant discrepancies in the mass balances were observed in excess formation of acetate and NH3, suggesting the presence of unknown metabolisms in T. kodakarensis grown in the rich medium containing pyruvate.
Collapse
|
29
|
Pawar SS, van Niel EWJ. Thermophilic biohydrogen production: how far are we? Appl Microbiol Biotechnol 2013; 97:7999-8009. [PMID: 23948723 PMCID: PMC3757257 DOI: 10.1007/s00253-013-5141-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 07/16/2013] [Accepted: 07/17/2013] [Indexed: 01/10/2023]
Abstract
Apart from being applied as an energy carrier, hydrogen is in increasing demand as a commodity. Currently, the majority of hydrogen (H2) is produced from fossil fuels, but from an environmental perspective, sustainable H2 production should be considered. One of the possible ways of hydrogen production is through fermentation, in particular, at elevated temperature, i.e. thermophilic biohydrogen production. This short review recapitulates the current status in thermophilic biohydrogen production through fermentation of commercially viable substrates produced from readily available renewable resources, such as agricultural residues. The route to commercially viable biohydrogen production is a multidisciplinary enterprise. Microbiological studies have pointed out certain desirable physiological characteristics in H2-producing microorganisms. More process-oriented research has identified best applicable reactor types and cultivation conditions. Techno-economic and life cycle analyses have identified key process bottlenecks with respect to economic feasibility and its environmental impact. The review has further identified current limitations and gaps in the knowledge, and also deliberates directions for future research and development of thermophilic biohydrogen production.
Collapse
Affiliation(s)
- Sudhanshu S Pawar
- Applied Microbiology, Lund University, Getingevägen 60, 222 41, Lund, Sweden.
| | | |
Collapse
|
30
|
Gupta SK, Kumari S, Reddy K, Bux F. Trends in biohydrogen production: major challenges and state-of-the-art developments. ENVIRONMENTAL TECHNOLOGY 2013; 34:1653-1670. [PMID: 24350426 DOI: 10.1080/09593330.2013.822022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Hydrogen has shown enormous potential to be an alternative fuel of the future. Hydrogen production technology has gained much attention in the last few decades due to advantages such as its high conversion efficiency, recyclability and non-polluting nature. Over the last few decades, biological hydrogen production has shown great promise for generating large scale sustainable energy to meet ever increasing global energy demands. Various microorganisms, namely bacteria, cyanobacteria, and algae which are capable of producing hydrogen from water, solar energy, and a variety of organic substrates, are explored and studied in detail. Current biohydrogen production technologies, however, face two major challenges such as low-yield and high production cost. Advances have been made in recent years in biohydrogen research to improve the hydrogen yield through process modifications, physiological manipulations, through metabolic and genetic engineering. Recently, cell immobilization such as microbes trapping with nanoparticles within the bioreactor has shown an increase in hydrogen production. This review critically evaluated various biological hydrogen production technologies, key challenges, and recent advancements in biohydrogen research and development.
Collapse
Affiliation(s)
- Sanjay Kumar Gupta
- Institute for Water and Wastewater Technology, Durban University of Technology, PO Box 1334, Durban 4000, South Africa
| | - Sheena Kumari
- Institute for Water and Wastewater Technology, Durban University of Technology, PO Box 1334, Durban 4000, South Africa
| | - Karen Reddy
- Institute for Water and Wastewater Technology, Durban University of Technology, PO Box 1334, Durban 4000, South Africa
| | - Faizal Bux
- Institute for Water and Wastewater Technology, Durban University of Technology, PO Box 1334, Durban 4000, South Africa
| |
Collapse
|
31
|
Waste valorization by biotechnological conversion into added value products. Appl Microbiol Biotechnol 2013; 97:6129-47. [DOI: 10.1007/s00253-013-5014-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 05/20/2013] [Accepted: 05/21/2013] [Indexed: 11/25/2022]
|
32
|
Cha M, Chung D, Elkins JG, Guss AM, Westpheling J. Metabolic engineering of Caldicellulosiruptor bescii yields increased hydrogen production from lignocellulosic biomass. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:85. [PMID: 23731756 PMCID: PMC3677179 DOI: 10.1186/1754-6834-6-85] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 05/28/2013] [Indexed: 05/07/2023]
Abstract
BACKGROUND Members of the anaerobic thermophilic bacterial genus Caldicellulosiruptor are emerging candidates for consolidated bioprocessing (CBP) because they are capable of efficiently growing on biomass without conventional pretreatment. C. bescii produces primarily lactate, acetate and hydrogen as fermentation products, and while some Caldicellulosiruptor strains produce small amounts of ethanol C. bescii does not, making it an attractive background to examine the effects of metabolic engineering. The recent development of methods for genetic manipulation has set the stage for rational engineering of this genus for improved biofuel production. Here, we report the first targeted gene deletion, the gene encoding lactate dehydrogenase (ldh), for metabolic engineering of a member of this genus. RESULTS A deletion of the C. bescii L-lactate dehydrogenase gene (ldh) was constructed on a non-replicating plasmid and introduced into the C. bescii chromosome by marker replacement. The resulting strain failed to produce detectable levels of lactate from cellobiose and maltose, instead increasing production of acetate and H2 by 21-34% relative to the wild type and ΔpyrFA parent strains. The same phenotype was observed on a real-world substrate - switchgrass (Panicum virgatum). Furthermore, the ldh deletion strain grew to a higher maximum optical density than the wild type on maltose and cellobiose, consistent with the prediction that the mutant would gain additional ATP with increased acetate production. CONCLUSIONS Deletion of ldh in C. bescii is the first use of recently developed genetic methods for metabolic engineering of these bacteria. This deletion resulted in a redirection of electron flow from production of lactate to acetate and hydrogen. New capabilities in metabolic engineering combined with intrinsic utilization of lignocellulosic materials position these organisms to provide a new paradigm for consolidated bioprocessing of fuels and other products from biomass.
Collapse
Affiliation(s)
- Minseok Cha
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Daehwan Chung
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - James G Elkins
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Adam M Guss
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Janet Westpheling
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| |
Collapse
|
33
|
Liu Z, Zhang C, Lu Y, Wu X, Wang L, Wang L, Han B, Xing XH. States and challenges for high-value biohythane production from waste biomass by dark fermentation technology. BIORESOURCE TECHNOLOGY 2013; 135:292-303. [PMID: 23186673 DOI: 10.1016/j.biortech.2012.10.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 10/05/2012] [Accepted: 10/08/2012] [Indexed: 05/25/2023]
Abstract
Hythane (H2+CH4) has attracted growing attention due to its versatile advantages as, for instance vehicle fuel. Biohythane consisting of biohydrogen and biomethane via two-stage fermentation is a potential high-value solution for the valorization of waste biomass resources and probably an alternative to the fossil based hythane. However, the significance and application potential of biohythane have not yet been fully recognized. This review focuses on the progress of biohydrogen and subsequent biomethane fermentation in terms of substrate, microbial consortium, reactor configuration, as well as the H2/CH4 ratio from the perspective of the feasibility of biohythane production in the past ten years. The current paper also covers how controls of the microbial consortium and bioprocess, system integration influence the biohythane productivity. Challenges and perspectives on biohythane technology will finally be addressed. This review provides a state-of-the-art technological insight into biohythane production by two-stage dark fermentation from biomass.
Collapse
Affiliation(s)
- Zhidan Liu
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
This article surveys methods for the enzymatic conversion of starch, involving hydrolases and nonhydrolyzing enzymes, as well as the role of microorganisms producing such enzymes. The sources of the most common enzymes are listed. These starch conversions are also presented in relation to their applications in the food, pharmaceutical, pulp, textile, and other branches of industry. Some sections are devoted to the fermentation of starch to ethanol and other products, and to the production of cyclodextrins, along with the properties of these products. Light is also shed on the enzymes involved in the digestion of starch in human and animal organisms. Enzymatic processes acting on starch are useful in structural studies of the substrates and in understanding the characteristics of digesting enzymes. One section presents the application of enzymes to these problems. The information that is included covers the period from the early 19th century up to 2009.
Collapse
|
35
|
Carere CR, Rydzak T, Verbeke TJ, Cicek N, Levin DB, Sparling R. Linking genome content to biofuel production yields: a meta-analysis of major catabolic pathways among select H2 and ethanol-producing bacteria. BMC Microbiol 2012; 12:295. [PMID: 23249097 PMCID: PMC3561251 DOI: 10.1186/1471-2180-12-295] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 12/12/2012] [Indexed: 12/16/2022] Open
Abstract
Background Fermentative bacteria offer the potential to convert lignocellulosic waste-streams into biofuels such as hydrogen (H2) and ethanol. Current fermentative H2 and ethanol yields, however, are below theoretical maxima, vary greatly among organisms, and depend on the extent of metabolic pathways utilized. For fermentative H2 and/or ethanol production to become practical, biofuel yields must be increased. We performed a comparative meta-analysis of (i) reported end-product yields, and (ii) genes encoding pyruvate metabolism and end-product synthesis pathways to identify suitable biomarkers for screening a microorganism’s potential of H2 and/or ethanol production, and to identify targets for metabolic engineering to improve biofuel yields. Our interest in H2 and/or ethanol optimization restricted our meta-analysis to organisms with sequenced genomes and limited branched end-product pathways. These included members of the Firmicutes, Euryarchaeota, and Thermotogae. Results Bioinformatic analysis revealed that the absence of genes encoding acetaldehyde dehydrogenase and bifunctional acetaldehyde/alcohol dehydrogenase (AdhE) in Caldicellulosiruptor, Thermococcus, Pyrococcus, and Thermotoga species coincide with high H2 yields and low ethanol production. Organisms containing genes (or activities) for both ethanol and H2 synthesis pathways (i.e. Caldanaerobacter subterraneus subsp. tengcongensis, Ethanoligenens harbinense, and Clostridium species) had relatively uniform mixed product patterns. The absence of hydrogenases in Geobacillus and Bacillus species did not confer high ethanol production, but rather high lactate production. Only Thermoanaerobacter pseudethanolicus produced relatively high ethanol and low H2 yields. This may be attributed to the presence of genes encoding proteins that promote NADH production. Lactate dehydrogenase and pyruvate:formate lyase are not conducive for ethanol and/or H2 production. While the type(s) of encoded hydrogenases appear to have little impact on H2 production in organisms that do not encode ethanol producing pathways, they do influence reduced end-product yields in those that do. Conclusions Here we show that composition of genes encoding pathways involved in pyruvate catabolism and end-product synthesis pathways can be used to approximate potential end-product distribution patterns. We have identified a number of genetic biomarkers for streamlining ethanol and H2 producing capabilities. By linking genome content, reaction thermodynamics, and end-product yields, we offer potential targets for optimization of either ethanol or H2 yields through metabolic engineering.
Collapse
Affiliation(s)
- Carlo R Carere
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, MB, Canada R3T 5V6
| | | | | | | | | | | |
Collapse
|
36
|
An archaeal histone is required for transformation of Thermococcus kodakarensis. J Bacteriol 2012; 194:6864-74. [PMID: 23065975 DOI: 10.1128/jb.01523-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Archaeal histones wrap DNA into complexes, designated archaeal nucleosomes, that resemble the tetrasome core of a eukaryotic nucleosome. Therefore, all DNA interactions in vivo in Thermococcus kodakarensis, the most genetically versatile model species for archaeal research, must occur in the context of a histone-bound genome. Here we report the construction and properties of T. kodakarensis strains that have TK1413 or TK2289 deleted, the genes that encode HTkA and HTkB, respectively, the two archaeal histones present in this archaeon. All attempts to generate a strain with both TK1413 and TK2289 deleted were unsuccessful, arguing that a histone-mediated event(s) in T. kodakarensis is essential. The HTkA and HTkB amino acid sequences are 84% identical (56 of 67 residues) and 94% similar (63 of 67 residues), but despite this homology and their apparent redundancy in terms of supporting viability, the absence of HTkA and HTkB resulted in differences in growth and in quantitative and qualitative differences in genome transcription. A most surprising result was that the deletion of TK1413 (ΔhtkA) resulted in a T. kodakarensis strain that was no longer amenable to transformation, whereas the deletion of TK2289 (ΔhtkB) had no detrimental effects on transformation. Potential roles for the archaeal histones in regulating gene expression and for HTkA in DNA uptake and recombination are discussed.
Collapse
|
37
|
Rittmann S, Herwig C. A comprehensive and quantitative review of dark fermentative biohydrogen production. Microb Cell Fact 2012; 11:115. [PMID: 22925149 PMCID: PMC3443015 DOI: 10.1186/1475-2859-11-115] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 08/03/2012] [Indexed: 01/25/2023] Open
Abstract
Biohydrogen production (BHP) can be achieved by direct or indirect biophotolysis, photo-fermentation and dark fermentation, whereof only the latter does not require the input of light energy. Our motivation to compile this review was to quantify and comprehensively report strains and process performance of dark fermentative BHP. This review summarizes the work done on pure and defined co-culture dark fermentative BHP since the year 1901. Qualitative growth characteristics and quantitative normalized results of H2 production for more than 2000 conditions are presented in a normalized and therefore comparable format to the scientific community.Statistically based evidence shows that thermophilic strains comprise high substrate conversion efficiency, but mesophilic strains achieve high volumetric productivity. Moreover, microbes of Thermoanaerobacterales (Family III) have to be preferred when aiming to achieve high substrate conversion efficiency in comparison to the families Clostridiaceae and Enterobacteriaceae. The limited number of results available on dark fermentative BHP from fed-batch cultivations indicates the yet underestimated potential of this bioprocessing application. A Design of Experiments strategy should be preferred for efficient bioprocess development and optimization of BHP aiming at improving medium, cultivation conditions and revealing inhibitory effects. This will enable comparing and optimizing strains and processes independent of initial conditions and scale.
Collapse
Affiliation(s)
- Simon Rittmann
- Institute of Chemical Engineering, Research Area Biochemical Engineering, Gumpendorferstraße 1a, Vienna University of Technology, Vienna, 1060, Austria
| | - Christoph Herwig
- Institute of Chemical Engineering, Research Area Biochemical Engineering, Gumpendorferstraße 1a, Vienna University of Technology, Vienna, 1060, Austria
| |
Collapse
|
38
|
Hileman TH, Santangelo TJ. Genetics Techniques for Thermococcus kodakarensis. Front Microbiol 2012; 3:195. [PMID: 22701112 PMCID: PMC3370424 DOI: 10.3389/fmicb.2012.00195] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 05/13/2012] [Indexed: 11/13/2022] Open
Abstract
Thermococcus kodakarensis (T. kodakarensis) has emerged as a premier model system for studies of archaeal biochemistry, genetics, and hyperthermophily. This prominence is derived largely from the natural competence of T. kodakarensis and the comprehensive, rapid, and facile techniques available for manipulation of the T. kodakarensis genome. These genetic capacities are complemented by robust planktonic growth, simple selections, and screens, defined in vitro transcription and translation systems, replicative expression plasmids, in vivo reporter constructs, and an ever-expanding knowledge of the regulatory mechanisms underlying T. kodakarensis metabolism. Here we review the existing techniques for genetic and biochemical manipulation of T. kodakarensis. We also introduce a universal platform to generate the first comprehensive deletion and epitope/affinity tagged archaeal strain libraries.
Collapse
Affiliation(s)
- Travis H Hileman
- Department of Microbiology, Center for RNA Biology, Ohio State University Columbus, OH, USA
| | | |
Collapse
|
39
|
Schut GJ, Nixon WJ, Lipscomb GL, Scott RA, Adams MWW. Mutational Analyses of the Enzymes Involved in the Metabolism of Hydrogen by the Hyperthermophilic Archaeon Pyrococcus furiosus. Front Microbiol 2012; 3:163. [PMID: 22557999 PMCID: PMC3341082 DOI: 10.3389/fmicb.2012.00163] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 04/12/2012] [Indexed: 11/21/2022] Open
Abstract
Pyrococcus furiosus grows optimally near 100°C by fermenting carbohydrates to produce hydrogen (H2) or, if elemental sulfur (S0) is present, hydrogen sulfide instead. It contains two cytoplasmic hydrogenases, SHI and SHII, that use NADP(H) as an electron carrier and a membrane-bound hydrogenase (MBH) that utilizes the redox protein ferredoxin. We previously constructed deletion strains lacking SHI and/or SHII and showed that they exhibited no obvious phenotype. This study has now been extended to include biochemical analyses and growth studies using the ΔSHI and ΔSHII deletion strains together with strains lacking a functional MBH (ΔmbhL). Hydrogenase activity in cytoplasmic extracts of various strains demonstrate that SHI is responsible for most of the cytoplasmic hydrogenase activity. The ΔmbhL strain showed no growth in the absence of S0, confirming the hypothesis that, in the absence of S0, MBH is the only enzyme that can dispose of reductant (in the form of H2) generated during sugar oxidation. Under conditions of limiting sulfur, a small but significant amount of H2 was produced by the ΔmbhL strain, showing that SHI can produce H2 from NADPH in vivo, although this does not enable growth of ΔmbhL in the absence of S0. We propose that the physiological function of SHI is to recycle H2 and provide a link between external H2 and the intracellular pool of NADPH needed for biosynthesis. This likely has a distinct energetic advantage in the environment, but it is clearly not required for growth of the organism under the usual laboratory conditions. The function of SHII, however, remains unknown.
Collapse
Affiliation(s)
- Gerrit J Schut
- Department of Biochemistry and Molecular Biology, University of Georgia Athens, GA, USA
| | | | | | | | | |
Collapse
|
40
|
Moon YJ, Kwon J, Yun SH, Lim HL, Kim MS, Kang SG, Lee JH, Choi JS, Kim SI, Chung YH. Proteome analyses of hydrogen-producing hyperthermophilic archaeon Thermococcus onnurineus NA1 in different one-carbon substrate culture conditions. Mol Cell Proteomics 2012; 11:M111.015420. [PMID: 22232491 DOI: 10.1074/mcp.m111.015420] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Thermococcus onnurineus NA1, a sulfur-reducing hyperthermophilic archaeon, is capable of H(2)-producing growth, considered to be hydrogenogenic carboxydotrophy. Utilization of formate as a sole energy source has been well studied in T. onnurineus NA1. However, whether formate can be used as its carbon source remains unknown. To obtain a global view of the metabolic characteristics of H(2)-producing growth, a quantitative proteome analysis of T. onnurineus NA1 grown on formate, CO, and starch was performed by combining one-dimensional SDS-PAGE with nano UPLC-MS(E). A total of 587 proteins corresponding to 29.7% of the encoding genes were identified, and the major metabolic pathways (especially energy metabolism) were characterized at the protein level. Expression of glycolytic enzymes was common but more highly induced in starch-grown cells. In contrast, enzymes involved in key steps of the gluconeogenesis and pentose phosphate pathways were strongly up-regulated in formate-grown cells, suggesting that formate could be utilized as a carbon source by T. onnurineus NA1. In accordance with the genomic analysis, comprehensive proteomic analysis also revealed a number of hydrogenase clusters apparently associated with formate metabolism. On the other hand, CODH and CO-induced hydrogenases belonging to the Hyg4-II cluster, as well as sulfhydrogenase-I and Mbx, were prominently expressed during CO culture. Our data suggest that CO can be utilized as a sole energy source for H(2) production via an electron transport mechanism and that CO(2) produced from catabolism or CO oxidation by CODH and CO-induced hydrogenases may subsequently be assimilated into the organic carbon. Overall, proteomic comparison of formate- and CO-grown cells with starch-grown cells revealed that a single carbon compound, such as formate and CO, can be utilized as an efficient substrate to provide cellular carbon and/or energy by T. onnurineus NA1.
Collapse
Affiliation(s)
- Yoon-Jung Moon
- Division of Life Science, Korea Basic Science Institute, Daejeon 305-806, Republic of Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Atomi H, Sato T, Kanai T. Application of hyperthermophiles and their enzymes. Curr Opin Biotechnol 2011; 22:618-26. [DOI: 10.1016/j.copbio.2011.06.010] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 06/14/2011] [Accepted: 06/16/2011] [Indexed: 12/27/2022]
|
42
|
Bae SS, Kim TW, Lee HS, Kwon KK, Kim YJ, Kim MS, Lee JH, Kang SG. H2 production from CO, formate or starch using the hyperthermophilic archaeon, Thermococcus onnurineus. Biotechnol Lett 2011; 34:75-9. [PMID: 21898132 DOI: 10.1007/s10529-011-0732-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2011] [Accepted: 08/24/2011] [Indexed: 10/17/2022]
Abstract
The hyperthermophilic archaeon, Thermococcus onnurineus, was grown in media supplemented with either CO, formate, or starch. H(2) was produced with each substrate with respective maximum rates of 1.55, 3.83 and 2.66 mmol H(2)/l h. The yields (mol H(2)/mol substrate) were 0.98, 1 and 3.13, respectively. This microbe is the first example where a single microorganism can grow and produce H(2) using CO, formate or starch as substrate.
Collapse
Affiliation(s)
- Seung Seob Bae
- Department of Marine Biotechnology, University of Science and Technology, Daejeon, 305-333, South Korea
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Cheng CL, Lo YC, Lee KS, Lee DJ, Lin CY, Chang JS. Biohydrogen production from lignocellulosic feedstock. BIORESOURCE TECHNOLOGY 2011; 102:8514-23. [PMID: 21570833 DOI: 10.1016/j.biortech.2011.04.059] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 04/18/2011] [Accepted: 04/19/2011] [Indexed: 05/16/2023]
Abstract
Due to the recent energy crisis and rising concern over climate change, the development of clean alternative energy sources is of significant interest. Biohydrogen produced from cellulosic feedstock, such as second generation feedstock (lignocellulosic biomass) and third generation feedstock (carbohydrate-rich microalgae), is a promising candidate as a clean, CO2-neutral, non-polluting and high efficiency energy carrier to meet the future needs. This article reviews state-of-the-art technology on lignocellulosic biohydrogen production in terms of feedstock pretreatment, saccharification strategy, and fermentation technology. Future developments of integrated biohydrogen processes leading to efficient waste reduction, low CO2 emission and high overall hydrogen yield is discussed.
Collapse
Affiliation(s)
- Chieh-Lun Cheng
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | | | | | | | | | | |
Collapse
|
44
|
Ciranna A, Santala V, Karp M. Biohydrogen production in alkalithermophilic conditions: Thermobrachium celere as a case study. BIORESOURCE TECHNOLOGY 2011; 102:8714-8722. [PMID: 21333530 DOI: 10.1016/j.biortech.2011.01.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 01/07/2011] [Accepted: 01/11/2011] [Indexed: 05/30/2023]
Abstract
In the present work the hydrogenesis in the anaerobic alkalithermophilic bacterium Thermobrachium celere was studied. The impact of several factors on hydrogen production during glucose fermentation was investigated in batch conditions. The optimal hydrogen production occurred at pH (67 °C) 8.2 with phosphate buffer concentration of 50 mM. Hydrogen yield reached the highest value of 3.36 mol H2/mol glucose when the partial pressure in the gas headspace was reduced. Supplementation of nitrogen sources and iron affected hydrogen production. Under optimized conditions, the maximum H2 accumulation and H2 production rate were estimated to be respectively 124.3 mmol H2/l culture and 20.7 mmol H2/l/h. Considering the efficient and rapid hydrogen evolution, and the ability to grow in extreme environments, T. celere might be a good candidate for biohydrogen production in open (non-sterile) bioprocess system.
Collapse
Affiliation(s)
- Alessandro Ciranna
- Department of Chemistry and Bioengineering, Tampere University of Technology, Tampere, Finland.
| | | | | |
Collapse
|
45
|
Lee DJ, Show KY, Su A. Dark fermentation on biohydrogen production: Pure culture. BIORESOURCE TECHNOLOGY 2011; 102:8393-402. [PMID: 21511469 DOI: 10.1016/j.biortech.2011.03.041] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 03/14/2011] [Accepted: 03/16/2011] [Indexed: 05/25/2023]
Abstract
Biohydrogen is regarded as an attractive future clean energy carrier due to its high energy content and environmental-friendly conversion. While biohydrogen production is still in the early stage of development, there have been a variety of laboratory- and pilot-scale systems developed with promising potential. This work presents a review of literature reports on the pure hydrogen-producers under anaerobic environment. Challenges and perspective of biohydrogen production with pure cultures are also outlined.
Collapse
Affiliation(s)
- Duu-Jong Lee
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.
| | | | | |
Collapse
|
46
|
Show KY, Lee DJ, Chang JS. Bioreactor and process design for biohydrogen production. BIORESOURCE TECHNOLOGY 2011; 102:8524-8533. [PMID: 21624834 DOI: 10.1016/j.biortech.2011.04.055] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2010] [Revised: 04/16/2011] [Accepted: 04/18/2011] [Indexed: 05/30/2023]
Abstract
Biohydrogen is regarded as an attractive future clean energy carrier due to its high energy content and environmental-friendly conversion. It has the potential for renewable biofuel to replace current hydrogen production which rely heavily on fossil fuels. While biohydrogen production is still in the early stage of development, there have been a variety of laboratory- and pilot-scale systems developed with promising potential. This work presents a review of advances in bioreactor and bioprocess design for biohydrogen production. The state-of-the art of biohydrogen production is discussed emphasizing on production pathways, factors affecting biohydrogen production, as well as bioreactor configuration and operation. Challenges and prospects of biohydrogen production are also outlined.
Collapse
Affiliation(s)
- Kuan-Yeow Show
- Department of Environmental Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Jalan University, Bandar Barat, 31900 Kampar, Perak, Malaysia
| | | | | |
Collapse
|
47
|
Oh YK, Raj SM, Jung GY, Park S. Current status of the metabolic engineering of microorganisms for biohydrogen production. BIORESOURCE TECHNOLOGY 2011; 102:8357-8367. [PMID: 21733680 DOI: 10.1016/j.biortech.2011.04.054] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 04/16/2011] [Accepted: 04/18/2011] [Indexed: 05/26/2023]
Abstract
The improvement of H2 production capabilities of hydrogen (H2)-producing microorganisms is a challenging issue. Microorganisms have evolved for fast growth and substrate utilization rather than H2 production. To develop good H2-producing biocatalysts, many studies have focused on the redirection and/or reconstruction of cellular metabolisms. These studies included the elimination of enzymes and carbon pathways interfering or competing with H2 production, the incorporation of non-native metabolic pathways leading to H2 production, the utilization of various carbon substrates, the rectification of H2-producting enzymes (nitrogenase and hydrogenase) and photophosphorylation systems, and in silico pathway flux analysis, among others. Owing to these studies, significant improvements in the yield and rate of H2 production, and in the stability of H2 production activity, were reached. This review presents and discusses the recent developments in biohydrogen production, with a focus on metabolic pathway engineering.
Collapse
Affiliation(s)
- You-Kwan Oh
- Bioenergy Center, Korea Institute of Energy Research, Daejeon 305-343, Republic of Korea
| | | | | | | |
Collapse
|
48
|
Lo YC, Huang LF, Cheng CL, Chen J, Chang JS. Using a starch-rich mutant of Arabidopsis thaliana as feedstock for fermentative hydrogen production. BIORESOURCE TECHNOLOGY 2011; 102:8543-8546. [PMID: 21546247 DOI: 10.1016/j.biortech.2011.04.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 04/10/2011] [Accepted: 04/11/2011] [Indexed: 05/30/2023]
Abstract
A mutant plant (Arabidopsis thaliana), sex1-1 (starch excess 1-1), accumulating high starch content in leaves was created to serve as better biomass feedstock for a H2-producing strain Clostridium butyricum CGS2, which efficiently utilizes starch for H2 production but cannot assimilate cellulosic materials. The starch content of the mutant plant increased to 10.67 mg/fresh weight, which is four times higher than that of wild type plant. Using sex1-1 mutant plant as feedstock, C. butyricum CGS2 could produce 490.4 ml/l of H2 with a H2 production rate of 32.9 ml/h/l. The H2 production performance appeared to increase with the increase in the concentration of mutant plant from 2.5 to 10 g/l. The highest H2 to plant biomass yield was nearly 49 ml/g for the mutant plant. This study successfully demonstrated the feasibility of using a starch-rich mutant plant for more effective bioH2 production with C. butyricum CGS2.
Collapse
Affiliation(s)
- Yung-Chung Lo
- Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan
| | | | | | | | | |
Collapse
|
49
|
Matsubara K, Yokooji Y, Atomi H, Imanaka T. Biochemical and genetic characterization of the three metabolic routes in Thermococcus kodakarensis linking glyceraldehyde 3-phosphate and 3-phosphoglycerate. Mol Microbiol 2011; 81:1300-12. [PMID: 21736643 DOI: 10.1111/j.1365-2958.2011.07762.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In the classical Embden-Meyerhof (EM) pathway for glycolysis, the conversion between glyceraldehyde 3-phosphate (GAP) and 3-phosphoglycerate (3-PGA) is reversibly catalysed by phosphorylating GAP dehydrogenase (GAPDH) and phosphoglycerate kinase (PGK). In the Euryarchaeota Thermococcus kodakarensis and Pyrococcus furiosus, an additional gene encoding GAP:ferredoxin oxidoreductase (GAPOR) and a gene similar to non-phosphorylating GAP dehydrogenase (GAPN) are present. In order to determine the physiological roles of the three routes that link GAP and 3-PGA, we individually disrupted the GAPOR, GAPN, GAPDH and PGK genes (gor, gapN, gapDH and pgk respectively) of T. kodakarensis. The Δgor strain displayed no growth under glycolytic conditions, confirming its proposed function to generate reduced ferredoxin for energy generation in glycolysis. Surprisingly, ΔgapN cells also did not grow under glycolytic conditions, suggesting that GAPN plays a key role in providing NADPH under these conditions. Disruption of gor and gapN had no effect on gluconeogenic growth. Growth experiments with the ΔgapDH and Δpgk strains indicated that, unlike their counterparts in the classical EM pathway, GAPDH/PGK play a major role only in gluconeogenesis. Biochemical analyses indicated that T. kodakarensis GAPN did not recognize aldehyde substrates other than d-GAP, preferred NADP(+) as cofactor and was dramatically activated with glucose 1-phosphate.
Collapse
Affiliation(s)
- Kohei Matsubara
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | | | | | | |
Collapse
|
50
|
Santangelo TJ, Cuboňová L, Reeve JN. Deletion of alternative pathways for reductant recycling in Thermococcus kodakarensis increases hydrogen production. Mol Microbiol 2011; 81:897-911. [PMID: 21749486 DOI: 10.1111/j.1365-2958.2011.07734.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Hydrogen (H₂) production by Thermococcus kodakarensis compares very favourably with the levels reported for the most productive algal, fungal and bacterial systems. T. kodakarensis can also consume H₂ and is predicted to use several alternative pathways to recycle reduced cofactors, some of which may compete with H₂ production for reductant disposal. To explore the reductant flux and possible competition for H₂ production in vivo, T. kodakarensis TS517 was mutated to precisely delete each of the alternative pathways of reductant disposal, H₂ production and consumption. The results obtained establish that H₂ is generated predominantly by the membrane-bound hydrogenase complex (Mbh), confirm the essential role of the SurR (TK1086p) regulator in vivo, delineate the roles of sulfur (S°) regulon proteins and demonstrate that preventing H₂ consumption results in a substantial net increase in H₂ production. Constitutive expression of TK1086 (surR) from a replicative plasmid restored the ability of T. kodakarensis TS1101 (ΔTK1086) to grow in the absence of S° and stimulated H₂ production, revealing a second mechanism to increase H₂ production. Transformation of T. kodakarensis TS1101 with plasmids that express SurR variants constructed to direct the constitutive synthesis of the Mbh complex and prevent expression of the S° regulon was only possible in the absence of S° and, under these conditions, the transformants exhibited wild-type growth and H₂ production. With S° present, they grew slower but synthesized more H₂ per unit biomass than T. kodakarensis TS517.
Collapse
Affiliation(s)
- Thomas J Santangelo
- Department of Microbiology and Center for RNA Biology, Ohio State University, Columbus, OH 43210, USA.
| | | | | |
Collapse
|