1
|
Chou KJ, Croft T, Hebdon SD, Magnusson LR, Xiong W, Reyes LH, Chen X, Miller EJ, Riley DM, Dupuis S, Laramore KA, Keller LM, Winkelman D, Maness PC. Engineering the cellulolytic bacterium, Clostridium thermocellum, to co-utilize hemicellulose. Metab Eng 2024; 83:193-205. [PMID: 38631458 DOI: 10.1016/j.ymben.2024.03.008] [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: 12/28/2023] [Revised: 03/15/2024] [Accepted: 03/29/2024] [Indexed: 04/19/2024]
Abstract
Consolidated bioprocessing (CBP) of lignocellulosic biomass holds promise to realize economic production of second-generation biofuels/chemicals, and Clostridium thermocellum is a leading candidate for CBP due to it being one of the fastest degraders of crystalline cellulose and lignocellulosic biomass. However, CBP by C. thermocellum is approached with co-cultures, because C. thermocellum does not utilize hemicellulose. When compared with a single-species fermentation, the co-culture system introduces unnecessary process complexity that may compromise process robustness. In this study, we engineered C. thermocellum to co-utilize hemicellulose without the need for co-culture. By evolving our previously engineered xylose-utilizing strain in xylose, an evolved clonal isolate (KJC19-9) was obtained and showed improved specific growth rate on xylose by ∼3-fold and displayed comparable growth to a minimally engineered strain grown on the bacteria's naturally preferred substrate, cellobiose. To enable full xylan deconstruction to xylose, we recombinantly expressed three different β-xylosidase enzymes originating from Thermoanaerobacterium saccharolyticum into KJC19-9 and demonstrated growth on xylan with one of the enzymes. This recombinant strain was capable of co-utilizing cellulose and xylan simultaneously, and we integrated the β-xylosidase gene into the KJC19-9 genome, creating the KJCBXint strain. The strain, KJC19-9, consumed monomeric xylose but accumulated xylobiose when grown on pretreated corn stover, whereas the final KJCBXint strain showed significantly greater deconstruction of xylan and xylobiose. This is the first reported C. thermocellum strain capable of degrading and assimilating hemicellulose polysaccharide while retaining its cellulolytic capabilities, unlocking significant potential for CBP in advancing the bioeconomy.
Collapse
Affiliation(s)
- Katherine J Chou
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA.
| | - Trevor Croft
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Skyler D Hebdon
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Lauren R Magnusson
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Wei Xiong
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Luis H Reyes
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA; Grupo de Diseño de Productos y Procesos, Department of Chemical and Food Engineering, Universidad de los Andes, Bogotá, Colombia
| | - Xiaowen Chen
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Emily J Miller
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Danielle M Riley
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Sunnyjoy Dupuis
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Kathrin A Laramore
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Lisa M Keller
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Dirk Winkelman
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| | - Pin-Ching Maness
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80228, USA
| |
Collapse
|
2
|
Influence of substrate loadings on the consolidated bioprocessing of rice straw and sugarcane bagasse biomass using Ruminiclostridium thermocellum. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.01.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
3
|
Xiong W, Reyes LH, Michener WE, Maness P, Chou KJ. Engineering cellulolytic bacterium
Clostridium thermocellum
to co‐ferment cellulose‐ and hemicellulose‐derived sugars simultaneously. Biotechnol Bioeng 2018. [DOI: 10.1002/bit.26590] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Wei Xiong
- National Renewable Energy Laboratory BioSciences Center GoldenColorado
| | - Luis H. Reyes
- National Renewable Energy Laboratory BioSciences Center GoldenColorado
- Product and Process Design Group, Department of Chemical Engineering Universidad de los Andes Bogotá D.C. Colombia
| | - William E. Michener
- National Renewable Energy Laboratory National Bioenergy Center GoldenColorado
| | - Pin‐Ching Maness
- National Renewable Energy Laboratory BioSciences Center GoldenColorado
| | - Katherine J. Chou
- National Renewable Energy Laboratory BioSciences Center GoldenColorado
| |
Collapse
|
4
|
Gadow SI, Jiang H, Li YY. Characterization and potential of three temperature ranges for hydrogen fermentation of cellulose by means of activity test and 16s rRNA sequence analysis. BIORESOURCE TECHNOLOGY 2016; 209:80-89. [PMID: 26954308 DOI: 10.1016/j.biortech.2016.02.098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/19/2016] [Accepted: 02/22/2016] [Indexed: 06/05/2023]
Abstract
A series of standardized activity experiments were performed to characterize three different temperature ranges of hydrogen fermentation from different carbon sources. 16S rRNA sequences analysis showed that the bacteria were close to Enterobacter genus in the mesophilic mixed culture (MMC) and Thermoanaerobacterium genus in the thermophilic and hyper-thermophilic mixed cultures (TMC and HMC). The MMC was able to utilize the glucose and cellulose to produce methane gas within a temperature range between 25 and 45 °C and hydrogen gas from 35 to 60°C. While, the TMC and HMC produced only hydrogen gas at all temperature ranges and the highest activity of 521.4mlH2/gVSSd was obtained by TMC. The thermodynamic analysis showed that more energy is consumed by hydrogen production from cellulose than from glucose. The experimental results could help to improve the economic feasibility of cellulosic biomass energy using three-phase technology to produce hythane.
Collapse
Affiliation(s)
- Samir I Gadow
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai 9808579, Japan; Department of Agricultural Microbiology, Agriculture and Biology Research Division, National Research Centre, Dokki, Cairo 12622, Egypt
| | - Hongyu Jiang
- Department of Environmental Science, Graduate School of Environmental Studies, Tohoku University, Sendai 9808579, Japan
| | - Yu-You Li
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai 9808579, Japan; Department of Environmental Science, Graduate School of Environmental Studies, Tohoku University, Sendai 9808579, Japan.
| |
Collapse
|
5
|
Patel AK, Debroy A, Sharma S, Saini R, Mathur A, Gupta R, Tuli DK. Biohydrogen production from a novel alkalophilic isolate Clostridium sp. IODB-O3. BIORESOURCE TECHNOLOGY 2015; 175:291-297. [PMID: 25459835 DOI: 10.1016/j.biortech.2014.10.110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 10/18/2014] [Accepted: 10/20/2014] [Indexed: 06/04/2023]
Abstract
Hydrogen producing bacteria IODB-O3 was isolated from sludge and identified as Clostridium sp. by 16S rDNA gene analysis. In this study, biohydrogen production process was developed using low-cost agro-waste. Maximum H2 was produced at 37°C and pH 8.5. Maximum H2 yield was obtained 2.54±0.2mol-H2/mol-reducing sugar from wheat straw pre-hydrolysate (WSPH) and 2.61±0.1mol-H2/mol-reducing sugar from pre-treated wheat straw enzymatic-hydrolysate (WSEH). The cumulative H2 production (ml/L), 3680±105 and 3270±100, H2 production rate (ml/L/h), 153±5 and 136±5, and specific H2 production (ml/g/h), 511±5 and 681±10 with WSPH and WSEH were obtained, respectively. Biomass pre-treatment via steam-explosion generates ample amount of WSPH which remains unutilized for bioethanol production due to non-availability of efficient C5-fermenting microorganisms. This study shows that Clostridium sp. IODB-O3 is capable of utilizing WSPH efficiently for biohydrogen production. This would lead to reduced economic constrain on the overall cellulosic ethanol process and also establish a sustainable biohydrogen production process.
Collapse
Affiliation(s)
- Anil Kumar Patel
- DBT-IOC Centre for Advanced Bio-Energy Research, Indian Oil Corporation Ltd, R&D Centre, Sector-13, Faridabad 121007, India.
| | - Arundhati Debroy
- DBT-IOC Centre for Advanced Bio-Energy Research, Indian Oil Corporation Ltd, R&D Centre, Sector-13, Faridabad 121007, India
| | - Sandeep Sharma
- DBT-IOC Centre for Advanced Bio-Energy Research, Indian Oil Corporation Ltd, R&D Centre, Sector-13, Faridabad 121007, India
| | - Reetu Saini
- DBT-IOC Centre for Advanced Bio-Energy Research, Indian Oil Corporation Ltd, R&D Centre, Sector-13, Faridabad 121007, India
| | - Anshu Mathur
- DBT-IOC Centre for Advanced Bio-Energy Research, Indian Oil Corporation Ltd, R&D Centre, Sector-13, Faridabad 121007, India
| | - Ravi Gupta
- DBT-IOC Centre for Advanced Bio-Energy Research, Indian Oil Corporation Ltd, R&D Centre, Sector-13, Faridabad 121007, India
| | - Deepak Kumar Tuli
- DBT-IOC Centre for Advanced Bio-Energy Research, Indian Oil Corporation Ltd, R&D Centre, Sector-13, Faridabad 121007, India
| |
Collapse
|
6
|
Levin DB, Hye Jo J, Maness PC. Biohydrogen Production from Cellulosic Biomass. INTEGRATED FOREST BIOREFINERIES 2012. [DOI: 10.1039/9781849735063-00256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Hydrogen can be produced by thermochemical, physicochemical, and biological processes. In contrast to thermo- and physicochemical processes, biological processes offer great potential for sustainable, renewable hydrogen production. Lignocellulosic biomass is renewable, inexpensive, constitutes a large fraction of waste biomass from municipal, agricultural, and forestry sectors, and thus offers excellent potential as a feedstock for renewable biofuels. Cellulose is, however, difficult to hydrolyze due to its crystalline structure. Biological hydrogen can be produced from cellulosic substrates by either hydrolyzing cellulose to sugars, followed by fermentation or by direct use of cellulose as the sole carbon source during fermentation. This chapter outlines the microbial basis of biological hydrogen production by cellulolytic bacteria, discusses the factors that influence hydrogen yields, and describes both single-phase and two-phase hydrogen production systems.
Collapse
Affiliation(s)
- David B Levin
- Department of Biosystems Engineering University of Manitoba Winnipeg, Manitoba, R3T 5V6 Canada
| | - Ji Hye Jo
- National Renewable Energy Laboratory 1617 Cole Blvd., Golden, Colorado, 80401 USA
| | - Pin-Ching Maness
- National Renewable Energy Laboratory 1617 Cole Blvd., Golden, Colorado, 80401 USA
| |
Collapse
|
7
|
Rydzak T, McQueen PD, Krokhin OV, Spicer V, Ezzati P, Dwivedi RC, Shamshurin D, Levin DB, Wilkins JA, Sparling R. Proteomic analysis of Clostridium thermocellum core metabolism: relative protein expression profiles and growth phase-dependent changes in protein expression. BMC Microbiol 2012; 12:214. [PMID: 22994686 PMCID: PMC3492117 DOI: 10.1186/1471-2180-12-214] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 09/11/2012] [Indexed: 01/21/2023] Open
Abstract
Background Clostridium thermocellum produces H2 and ethanol, as well as CO2, acetate, formate, and lactate, directly from cellulosic biomass. It is therefore an attractive model for biofuel production via consolidated bioprocessing. Optimization of end-product yields and titres is crucial for making biofuel production economically feasible. Relative protein expression profiles may provide targets for metabolic engineering, while understanding changes in protein expression and metabolism in response to carbon limitation, pH, and growth phase may aid in reactor optimization. We performed shotgun 2D-HPLC-MS/MS on closed-batch cellobiose-grown exponential phase C. thermocellum cell-free extracts to determine relative protein expression profiles of core metabolic proteins involved carbohydrate utilization, energy conservation, and end-product synthesis. iTRAQ (isobaric tag for relative and absolute quantitation) based protein quantitation was used to determine changes in core metabolic proteins in response to growth phase. Results Relative abundance profiles revealed differential levels of putative enzymes capable of catalyzing parallel pathways. The majority of proteins involved in pyruvate catabolism and end-product synthesis were detected with high abundance, with the exception of aldehyde dehydrogenase, ferredoxin-dependent Ech-type [NiFe]-hydrogenase, and RNF-type NADH:ferredoxin oxidoreductase. Using 4-plex 2D-HPLC-MS/MS, 24% of the 144 core metabolism proteins detected demonstrated moderate changes in expression during transition from exponential to stationary phase. Notably, proteins involved in pyruvate synthesis decreased in stationary phase, whereas proteins involved in glycogen metabolism, pyruvate catabolism, and end-product synthesis increased in stationary phase. Several proteins that may directly dictate end-product synthesis patterns, including pyruvate:ferredoxin oxidoreductases, alcohol dehydrogenases, and a putative bifurcating hydrogenase, demonstrated differential expression during transition from exponential to stationary phase. Conclusions Relative expression profiles demonstrate which proteins are likely utilized in carbohydrate utilization and end-product synthesis and suggest that H2 synthesis occurs via bifurcating hydrogenases while ethanol synthesis is predominantly catalyzed by a bifunctional aldehyde/alcohol dehydrogenase. Differences in expression profiles of core metabolic proteins in response to growth phase may dictate carbon and electron flux towards energy storage compounds and end-products. Combined knowledge of relative protein expression levels and their changes in response to physiological conditions may aid in targeted metabolic engineering strategies and optimization of fermentation conditions for improvement of biofuels production.
Collapse
Affiliation(s)
- Thomas Rydzak
- Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
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
|
9
|
Ellis LD, Holwerda EK, Hogsett D, Rogers S, Shao X, Tschaplinski T, Thorne P, Lynd LR. Closing the carbon balance for fermentation by Clostridium thermocellum (ATCC 27405). BIORESOURCE TECHNOLOGY 2012; 103:293-9. [PMID: 22055095 DOI: 10.1016/j.biortech.2011.09.128] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 09/27/2011] [Accepted: 09/28/2011] [Indexed: 05/18/2023]
Abstract
Our lab and most others have not been able to close a carbon balance for fermentation by the thermophilic, cellulolytic anaerobe, Clostridium thermocellum. We undertook a detailed accounting of product formation in C. thermocellum ATCC 27405. Elemental analysis revealed that for both cellulose (Avicel) and cellobiose, ≥92% of the substrate carbon utilized could be accounted for in the pellet, supernatant and off-gas when including sampling. However, 11.1% of the original substrate carbon was found in the liquid phase and not in the form of commonly-measured fermentation products--ethanol, acetate, lactate, and formate. Further detailed analysis revealed all the products to be <720 da and have not usually been associated with C. thermocellum fermentation, including malate, pyruvate, uracil, soluble glucans, and extracellular free amino acids. By accounting for these products, 92.9% and 93.2% of the final product carbon was identified during growth on cellobiose and Avicel, respectively.
Collapse
Affiliation(s)
- Lucas D Ellis
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Raman B, McKeown CK, Rodriguez M, Brown SD, Mielenz JR. Transcriptomic analysis of Clostridium thermocellum ATCC 27405 cellulose fermentation. BMC Microbiol 2011; 11:134. [PMID: 21672225 PMCID: PMC3130646 DOI: 10.1186/1471-2180-11-134] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 06/14/2011] [Indexed: 01/18/2023] Open
Abstract
Background The ability of Clostridium thermocellum ATCC 27405 wild-type strain to hydrolyze cellulose and ferment the degradation products directly to ethanol and other metabolic byproducts makes it an attractive candidate for consolidated bioprocessing of cellulosic biomass to biofuels. In this study, whole-genome microarrays were used to investigate the expression of C. thermocellum mRNA during growth on crystalline cellulose in controlled replicate batch fermentations. Results A time-series analysis of gene expression revealed changes in transcript levels of ~40% of genes (~1300 out of 3198 ORFs encoded in the genome) during transition from early-exponential to late-stationary phase. K-means clustering of genes with statistically significant changes in transcript levels identified six distinct clusters of temporal expression. Broadly, genes involved in energy production, translation, glycolysis and amino acid, nucleotide and coenzyme metabolism displayed a decreasing trend in gene expression as cells entered stationary phase. In comparison, genes involved in cell structure and motility, chemotaxis, signal transduction and transcription showed an increasing trend in gene expression. Hierarchical clustering of cellulosome-related genes highlighted temporal changes in composition of this multi-enzyme complex during batch growth on crystalline cellulose, with increased expression of several genes encoding hydrolytic enzymes involved in degradation of non-cellulosic substrates in stationary phase. Conclusions Overall, the results suggest that under low substrate availability, growth slows due to decreased metabolic potential and C. thermocellum alters its gene expression to (i) modulate the composition of cellulosomes that are released into the environment with an increased proportion of enzymes than can efficiently degrade plant polysaccharides other than cellulose, (ii) enhance signal transduction and chemotaxis mechanisms perhaps to sense the oligosaccharide hydrolysis products, and nutrient gradients generated through the action of cell-free cellulosomes and, (iii) increase cellular motility for potentially orienting the cells' movement towards positive environmental signals leading to nutrient sources. Such a coordinated cellular strategy would increase its chances of survival in natural ecosystems where feast and famine conditions are frequently encountered.
Collapse
Affiliation(s)
- Babu Raman
- Biosciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, USA
| | | | | | | | | |
Collapse
|
11
|
RenNanqi, GuoWanqian, LiuBingfeng, CaoGuangli, DingJie. Biological hydrogen production by dark fermentation: challenges and prospects towards scaled-up production. Curr Opin Biotechnol 2011; 22:365-70. [PMID: 21612910 DOI: 10.1016/j.copbio.2011.04.022] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 04/23/2011] [Accepted: 04/27/2011] [Indexed: 11/30/2022]
Abstract
Among different technologies of hydrogen production, bio-hydrogen production exhibits perhaps the greatest potential to replace fossil fuels. Based on recent research on dark fermentative hydrogen production, this article reviews the following aspects towards scaled-up application of this technology: bioreactor development and parameter optimization, process modeling and simulation, exploitation of cheaper raw materials and combining dark-fermentation with photo-fermentation. Bioreactors are necessary for dark-fermentation hydrogen production, so the design of reactor type and optimization of parameters are essential. Process modeling and simulation can help engineers design and optimize large-scale systems and operations. Use of cheaper raw materials will surely accelerate the pace of scaled-up production of biological hydrogen. And finally, combining dark-fermentation with photo-fermentation holds considerable promise, and has successfully achieved maximum overall hydrogen yield from a single substrate. Future development of bio-hydrogen production will also be discussed.
Collapse
Affiliation(s)
- RenNanqi
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | | | | | | | | |
Collapse
|
12
|
Verhaart MRA, Bielen AAM, van der Oost J, Stams AJM, Kengen SWM. Hydrogen production by hyperthermophilic and extremely thermophilic bacteria and archaea: mechanisms for reductant disposal. ENVIRONMENTAL TECHNOLOGY 2010; 31:993-1003. [PMID: 20662387 DOI: 10.1080/09593331003710244] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Hydrogen produced from biomass by bacteria and archaea is an attractive renewable energy source. However, to make its application more feasible, microorganisms are needed with high hydrogen productivities. For several reasons, hyperthermophilic and extremely thermophilic bacteria and archaea are promising is this respect. In addition to the high polysaccharide-hydrolysing capacities of many of these organisms, an important advantage is their ability to use most of the reducing equivalents (e.g. NADH, reduced ferredoxin) formed during glycolysis for the production of hydrogen, enabling H2/hexose ratios of between 3.0 and 4.0. So, despite the fact that the hydrogen-yielding reactions, especially the one from NADH, are thermodynamically unfavourable, high hydrogen yields are obtained. In this review we focus on three different mechanisms that are employed by a few model organisms, viz. Caldicellulosiruptor saccharolyticus and Thermoanaerobacter tengcongensis, Thermotoga maritima, and Pyrococcus furiosus, to efficiently produce hydrogen. In addition, recent developments to improve hydrogen production by hyperthermophilic and extremely thermophilic bacteria and archaea are discussed.
Collapse
Affiliation(s)
- Marcel R A Verhaart
- Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands
| | | | | | | | | |
Collapse
|