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Le Y, Zhang M, Wu P, Wang H, Ni J. Biofuel production from lignocellulose via thermophile-based consolidated bioprocessing. ENGINEERING MICROBIOLOGY 2024; 4:100174. [PMID: 39628591 PMCID: PMC11610967 DOI: 10.1016/j.engmic.2024.100174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 09/07/2024] [Accepted: 09/08/2024] [Indexed: 12/06/2024]
Abstract
The depletion of fossil fuels and their impact on the environment have led to efforts to develop alternative sustainable fuels. While biofuel derived from lignocellulose is considered a sustainable, renewable, and green energy source, enhancing biofuel production and achieving a cost-effective bioconversion of lignocellulose at existing bio-refineries remains a challenge. Consolidated bioprocessing (CBP) using thermophiles can simplify this operation by integrating multiple processes, such as hydrolytic enzyme production, lignocellulose degradation, biofuel fermentation, and product distillation. This paper reviews recent developments in the conversion of lignocellulose to biofuel using thermophile-based CBP. First, advances in thermostable enzyme and thermophilic lignocellulolytic microorganism discovery and development for lignocellulosic biorefinery use are outlined. Then, several thermophilic CBP candidates and thermophilic microbes engineered to drive CBP of lignocellulose are reviewed. CRISPR/Cas-based genome editing tools developed for thermophiles are also highlighted. The potential applications of the Design-Build-Test-Learn (DBTL) synthetic biology strategy for designing and constructing thermophilic CBP hosts are also discussed in detail. Overall, this review illustrates how to develop highly sophisticated thermophilic CBP hosts for use in lignocellulosic biorefinery applications.
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Affiliation(s)
- Yilin Le
- Biofuels Institute, School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Mengqi Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Pengju Wu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Huilei Wang
- Biofuels Institute, School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Jinfeng Ni
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
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2
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Biswa Sarma J, Mahanta S, Tanti B. Maximizing microbial activity and synergistic interaction to boost biofuel production from lignocellulosic biomass. Arch Microbiol 2024; 206:448. [PMID: 39470782 DOI: 10.1007/s00203-024-04172-4] [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: 08/27/2024] [Revised: 10/14/2024] [Accepted: 10/14/2024] [Indexed: 11/01/2024]
Abstract
Addressing global environmental challenges and meeting the escalating energy demands stand as two pivotal issues in the current landscape. Lignocellulosic biomass emerges as a promising renewable bio-energy source capable of fulfilling the world's energy requirements on a large scale. One of the most important steps in lowering reliance on fossil fuel and lessening environmental effect is turning lignocellulosic biomass into biofuel. As carbon-neutral substitutes for traditional fuel, biofuel offer a solution to environmental concerns compared to conventional fuel. Effective utilization of lignocellulosic biomass is imperative for sustainable development. Ongoing research focuses on exploring the potential of various microorganisms and their co-interactions to synthesize diverse biofuels from different starting materials, including lignocellulosic biomass. Co-culture techniques demonstrate resilience to nutrient scarcity and environmental fluctuations. By utilising a variety of carbon sources, microbes can enhance their adaptability to environmental stressors and potentially increase productivity through their symbiotic interactions. Furthermore, compared to single organism involvement, co-interactions allow faster execution of multistep processes. Lignocellulosic biomass serves as a primary substrate for pre-treatment, fermentation, and enzymatic hydrolysis processes. This review primarily delves into the pretreatment, enzymatic hydrolysis process and the biochemical pathways involved in converting lignocellulosic biomass into bioenergy.
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Affiliation(s)
- Janayita Biswa Sarma
- Department of Energy Engineering, Assam Science and Technology University, Jalukbari, Tetelia, Guwahati, 781011, Assam, India
| | - Saurov Mahanta
- National Institute of Electronics and Information Technology, Guwahati, 781022, Assam, India.
| | - Bhaben Tanti
- Department of Botany, Gauhati University, Jalukbari, Guwahati, 781014, Assam, India
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3
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Wang J, Wang W, Chen Y, Liu Z, Ji X, Pan G, Li Z, Fan K. Development of a xylose-inducible and glucose-insensitive expression system for Parageobacillus thermoglucosidasius. Appl Microbiol Biotechnol 2024; 108:493. [PMID: 39441395 PMCID: PMC11499391 DOI: 10.1007/s00253-024-13333-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 09/06/2024] [Accepted: 10/15/2024] [Indexed: 10/25/2024]
Abstract
Inducible expression systems are pivotal for governing gene expression in strain engineering and synthetic biotechnological applications. Therefore, a critical need persists for the development of versatile and efficient inducible expression mechanisms. In this study, the xylose-responsive promoter xylA5p and its transcriptional regulator XylR were identified in Parageobacillus thermoglucosidasius DSM 2542. By combining promoter xylA5p with its regulator XylR, fine-tuning the expression strength of XylR, and reducing the glucose catabolite repression on xylose uptake, we successfully devised a xylose-inducible and glucose-insensitive expression system, denoted as IExyl*. This system exhibited diverse promoter strengths upon induction with xylose at varying concentrations and remained unhindered in the presence of glucose. Moreover, we showed the applicability of IExyl* in P. thermoglucosidasius by redirecting metabolic flux towards riboflavin biosynthesis, culminating in a 2.8-fold increase in riboflavin production compared to that of the starting strain. This glucose-insensitive and xylose-responsive expression system provides valuable tools for designing optimized biosynthetic pathways for high-value products and facilitates future synthetic biology investigations in Parageobacillus. KEY POINTS: • A xylose-inducible and glucose-insensitive expression system IExyl* was developed. • IExyl* was applied to enhance the riboflavin production in P. thermoglucosidasius • A tool for metabolic engineering and synthetic biology research in Parageobacillus strains.
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Affiliation(s)
- Junyang Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- College of Life Science and Technology, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Weishan Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yihua Chen
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zihe Liu
- College of Life Science and Technology, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Xu Ji
- College of Life Science and Technology, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Guohui Pan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zilong Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Keqiang Fan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
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4
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Zhang M, Shi H, Wang X, Zhu Y, Li Z, Tu L, Zheng Y, Xia M, Wang W, Wang M. AI-based automated construction of high-precision Geobacillus thermoglucosidasius enzyme constraint model. Metab Eng 2024; 86:208-233. [PMID: 39427974 DOI: 10.1016/j.ymben.2024.10.006] [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: 07/06/2024] [Revised: 09/27/2024] [Accepted: 10/15/2024] [Indexed: 10/22/2024]
Abstract
Geobacillus thermoglucosidasius NCIMB 11955 possesses advantages, such as high-temperature tolerance, rapid growth rate, and low contamination risk. Additionally, it features efficient gene editing tools, making it one of the most promising next-generation cell factories. However, as a non-model microorganism, a lack of metabolic information significantly hampers the construction of high-precision metabolic flux models. Here, we propose a BioIntelliModel (BIM) strategy based on artificial intelligence technology for the automated construction of enzyme-constrained models. 1). BIM utilises the Contrastive Learning Enabled Enzyme Annotation (CLEAN) prediction tool to analyse the entire genome sequence of G. thermoglucosidasius NCIMB 11955, uncovering potential functional proteins in non-model strains. 2). The MetaPatchM module of BIM automates the repair of the metabolic network model. 3). The Tianjin University of Science and Technology-kcat (TUST-kcat) module predicts the kcat values of enzymes within the model. 4). The Enzyme-insert procedure constructs an enzyme-constrained model and performs a global scan to address overconstraint issues. Enzymatic data were automatically integrated into the metabolic flux model, creating an enzyme-constrained model, ec_G-ther11955. To validate model accuracy, we used both the p-thermo and ec_G-ther11955 models to predict riboflavin production strategies. The ec_G-ther11955 model demonstrated significantly higher accuracy. To further verify its efficacy, we employed ec_G-ther11955 to guide the rational design of L-valine-producing strains. Using the Optimisation Procedure for Identifying All Genetic Manipulations Leading to Targeted Overproductions (OptForce), Predictive Knockout Targeting (PKT), and Flux Scanning based on Enforced Objective Flux (FSEOF) algorithms, we identified 24 knockout and overexpression targets, achieving an accuracy rate of 87.5%. Ultimately, this led to an increase of 664.04% in L-valine titre. This study provides a novel strategy for rapidly constructing non-model strain models and demonstrates the tremendous potential of artificial intelligence in metabolic engineering.
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Affiliation(s)
- Minghao Zhang
- State Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.
| | - Haijiao Shi
- State Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Xiaohong Wang
- State Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Yanan Zhu
- State Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Zilong Li
- Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Linna Tu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Yu Zheng
- State Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Menglei Xia
- State Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.
| | - Weishan Wang
- Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Min Wang
- State Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.
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5
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Böer T, Engelhardt L, Lüschen A, Eysell L, Yoshida H, Schneider D, Angenent LT, Basen M, Daniel R, Poehlein A. Isolation and characterization of novel acetogenic Moorella strains for employment as potential thermophilic biocatalysts. FEMS Microbiol Ecol 2024; 100:fiae109. [PMID: 39118367 PMCID: PMC11328732 DOI: 10.1093/femsec/fiae109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 06/05/2024] [Accepted: 08/07/2024] [Indexed: 08/10/2024] Open
Abstract
Thermophilic acetogenic bacteria have attracted attention as promising candidates for biotechnological applications such as syngas fermentation, microbial electrosynthesis, and methanol conversion. Here, we aimed to isolate and characterize novel thermophilic acetogens from diverse environments. Enrichment of heterotrophic and autotrophic acetogens was monitored by 16S rRNA gene-based bacterial community analysis. Seven novel Moorella strains were isolated and characterized by genomic and physiological analyses. Two Moorella humiferrea isolates showed considerable differences during autotrophic growth. The M. humiferrea LNE isolate (DSM 117358) fermented carbon monoxide (CO) to acetate, while the M. humiferrea OCP isolate (DSM 117359) transformed CO to hydrogen and carbon dioxide (H2 + CO2), employing the water-gas shift reaction. Another carboxydotrophic hydrogenogenic Moorella strain was isolated from the covering soil of an active charcoal burning pile and proposed as the type strain (ACPsT) of the novel species Moorella carbonis (DSM 116161T and CCOS 2103T). The remaining four novel strains were affiliated with Moorella thermoacetica and showed, together with the type strain DSM 2955T, the production of small amounts of ethanol from H2 + CO2 in addition to acetate. The physiological analyses of the novel Moorella strains revealed isolate-specific differences that considerably increase the knowledge base on thermophilic acetogens for future applications.
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Affiliation(s)
- Tim Böer
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Lisa Engelhardt
- Microbiology, Institute of Biological Sciences, University Rostock, 18059 Rostock, Germany
| | - Alina Lüschen
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Lena Eysell
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Hiroki Yoshida
- Environmental Biotechnology Group, Department of Geosciences, University of Tübingen, 72074 Tübingen, Germany
| | - Dominik Schneider
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Largus T Angenent
- Environmental Biotechnology Group, Department of Geosciences, University of Tübingen, 72074 Tübingen, Germany
| | - Mirko Basen
- Microbiology, Institute of Biological Sciences, University Rostock, 18059 Rostock, Germany
| | - Rolf Daniel
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Anja Poehlein
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
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6
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Kato J, Fujii T, Kato S, Wada K, Watanabe M, Nakamichi Y, Aoi Y, Morita T, Murakami K, Nakashimada Y. Genetic engineering of a thermophilic acetogen, Moorella thermoacetica Y72, to enable acetoin production. Front Bioeng Biotechnol 2024; 12:1398467. [PMID: 38812916 PMCID: PMC11133584 DOI: 10.3389/fbioe.2024.1398467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Accepted: 04/29/2024] [Indexed: 05/31/2024] Open
Abstract
Acetogens are among the key microorganisms involved in the bioproduction of commodity chemicals from diverse carbon resources, such as biomass and waste gas. Thermophilic acetogens are particularly attractive because fermentation at higher temperatures offers multiple advantages. However, the main target product is acetic acid. Therefore, it is necessary to reshape metabolism using genetic engineering to produce the desired chemicals with varied carbon lengths. Although such metabolic engineering has been hampered by the difficulty involved in genetic modification, a model thermophilic acetogen, M. thermoacetica ATCC 39073, is the case with a few successful cases of C2 and C3 compound production, other than acetate. This brief report attempts to expand the product spectrum to include C4 compounds by using strain Y72 of Moorella thermoacetica. Strain Y72 is a strain related to the type strain ATCC 39073 and has been reported to have a less stringent restriction-modification system, which could alleviate the cumbersome transformation process. A simplified procedure successfully introduced a key enzyme for acetoin (a C4 chemical) production, and the resulting strains produced acetoin from sugars and gaseous substrates. The culture profile revealed varied acetoin yields depending on the type of substrate and culture conditions, implying the need for further engineering in the future. Thus, the use of a user-friendly chassis could benefit the genetic engineering of M. thermoacetica.
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Affiliation(s)
- Junya Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Hiroshima, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Hiroshima, Japan
| | - Tatsuya Fujii
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Hiroshima, Japan
| | - Setsu Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Hiroshima, Japan
| | - Keisuke Wada
- National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan
| | - Masahiro Watanabe
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Hiroshima, Japan
| | - Yusuke Nakamichi
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Hiroshima, Japan
| | - Yoshiteru Aoi
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Hiroshima, Japan
| | - Tomotake Morita
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Hiroshima, Japan
| | - Katsuji Murakami
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Hiroshima, Japan
| | - Yutaka Nakashimada
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Hiroshima, Japan
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7
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Lau MH, Madika A, Zhang Y, Minton NP. Parageobacillus thermoglucosidasius Strain Engineering Using a Theophylline Responsive RiboCas for Controlled Gene Expression. ACS Synth Biol 2024; 13:1237-1245. [PMID: 38517011 PMCID: PMC11036489 DOI: 10.1021/acssynbio.3c00735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/29/2024] [Accepted: 02/29/2024] [Indexed: 03/23/2024]
Abstract
The relentless increase in atmospheric greenhouse gas concentrations as a consequence of the exploitation of fossil resources compels the adoption of sustainable routes to chemical and fuel manufacture based on biological fermentation processes. The use of thermophilic chassis in such processes is an attractive proposition; however, their effective exploitation will require improved genome editing tools. In the case of the industrially relevant chassis Parageobacillus thermoglucosidasius, CRISPR/Cas9-based gene editing has been demonstrated. The constitutive promoter used, however, accentuates the deleterious nature of Cas9, causing decreased transformation and low editing efficiencies, together with an increased likelihood of off-target effects or alternative mutations. Here, we rectify this issue by controlling the expression of Cas9 through the use of a synthetic riboswitch that is dependent on the nonmetabolized, nontoxic, and cheap inducer, theophylline. We demonstrate that the riboswitches are dose-dependent, allowing for controlled expression of the target gene. Through their use, we were then able to address the deleterious nature of Cas9 and produce an inducible system, RiboCas93. The benefits of RiboCas93 were demonstrated by increased transformation efficiency of the editing vectors, improved efficiency in mutant generation (100%), and a reduction of Cas9 toxicity, as indicated by a reduction in the number of single nucleotide polymorphisms (SNPs) observed. This new system provides a quick and efficient way to produce mutants in P. thermoglucosidasius.
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Affiliation(s)
- Matthew
S. H. Lau
- BBSRC/EPSRC
Synthetic Biology Research Centre (SBRC), Biodiscovery Institute,
School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
| | - Abubakar Madika
- BBSRC/EPSRC
Synthetic Biology Research Centre (SBRC), Biodiscovery Institute,
School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
- Department
of Microbiology, Faculty of Life Sciences, Ahmadu Bello University, Zaria 810107, Nigeria
| | - Ying Zhang
- BBSRC/EPSRC
Synthetic Biology Research Centre (SBRC), Biodiscovery Institute,
School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
| | - Nigel P. Minton
- BBSRC/EPSRC
Synthetic Biology Research Centre (SBRC), Biodiscovery Institute,
School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
- NIHR
Nottingham Biomedical Research Centre, Nottingham
University Hospitals NHS Trust and The University of Nottingham, Nottingham NG7 2RD, U.K.
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8
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Wang Y, Qian J, Shi T, Wang Y, Ding Q, Ye C. Application of extremophile cell factories in industrial biotechnology. Enzyme Microb Technol 2024; 175:110407. [PMID: 38341913 DOI: 10.1016/j.enzmictec.2024.110407] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/24/2024] [Accepted: 01/26/2024] [Indexed: 02/13/2024]
Abstract
Due to the extreme living conditions, extremophiles have unique characteristics in morphology, structure, physiology, biochemistry, molecular evolution mechanism and so on. Extremophiles have superior growth and synthesis capabilities under harsh conditions compared to conventional microorganisms, allowing for unsterilized fermentation processes and thus better performance in low-cost production. In recent years, due to the development and optimization of molecular biology, synthetic biology and fermentation technology, the identification and screening technology of extremophiles has been greatly improved. In this review, we summarize techniques for the identification and screening of extremophiles and review their applications in industrial biotechnology in recent years. In addition, the facts and perspectives gathered in this review suggest that next-generation industrial biotechnology (NGIBs) based on engineered extremophiles holds the promise of simplifying biofuturing processes, establishing open, non-sterilized continuous fermentation production systems, and utilizing low-cost substrates to make NGIBs attractive and cost-effective bioprocessing technologies for sustainable manufacturing.
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Affiliation(s)
- Yuzhou Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Jinyi Qian
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Tianqiong Shi
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Yuetong Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Qiang Ding
- School of Life Sciences, Anhui University, Hefei 230601, PR China.
| | - Chao Ye
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China; Ministry of Education Key Laboratory of NSLSCS.
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9
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Rajeswari G, Kumar V, Jacob S. A concerted enzymatic de-structuring of lignocellulosic materials using a compost-derived microbial consortia favoring the consolidated pretreatment and bio-saccharification. Enzyme Microb Technol 2024; 174:110393. [PMID: 38219439 DOI: 10.1016/j.enzmictec.2023.110393] [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: 08/30/2023] [Revised: 11/24/2023] [Accepted: 12/29/2023] [Indexed: 01/16/2024]
Abstract
The robustness of microbial consortia isolated from compost habitat encompasses the complementary metabolism that aids in consolidated bioprocessing (CBP) of lignocellulosic biomass (LCB) by division of labor across the symbionts. Composting of organic waste is deemed to be an efficient way of carbon recycling, where the syntrophic microbial population exerts a concerted action of lignin and polysaccharide (hemicellulose and cellulose) component of plant biomass. The potential of this interrelated microorganism could be enhanced through adaptive laboratory evolution (ALE) with LCB for its desired functional capabilities. Therefore, in this study, microbial symbionts derived from organic compost was enriched on saw dust (SD) (woody biomass), aloe vera leaf rind (AVLR) (agro-industrial waste) and commercial filter paper (FP) (pure cellulose) through ALE under different conditions. Later, the efficacy of enriched consortium (EC) on consolidated pretreatment and bio-saccharification was determined based on substrate degradation, endo-enzymes profiling and fermentable sugar yield. Among the treatment sets, AVLR biomass treated with EC-5 has resulted in the higher degradation rate of lignin (47.01 ± 0.66%, w/w) and polysaccharides (45.87 ± 1.82%, w/w) with a total sugar yield of about 60.01 ± 4.24 mg/g. In addition, the extent of structural disintegration of substrate after EC-treatment was clearly deciphered by FTIR and XRD analysis. And the factors of Pearson correlation matrix reinforces the potency of EC-5 by exhibiting a strong positive correlation between AVLR degradation and the sugar release. Thus, a consortium based CBP could promote the feasibility of establishing a sustainable second generation biorefinery framework.
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Affiliation(s)
- Gunasekaran Rajeswari
- Department of Biotechnology, School of Bioengineering, College of Engineering and Technology, Faculty of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Chengalpattu District, Kattankulathur 603203, Tamil Nadu, India
| | - Vinod Kumar
- School of Water, Energy and Environment, Cranfield University, Cranfield MK43 0AL, UK.
| | - Samuel Jacob
- Department of Biotechnology, School of Bioengineering, College of Engineering and Technology, Faculty of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Chengalpattu District, Kattankulathur 603203, Tamil Nadu, India.
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10
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Su Y, Mangus AM, Cordell WT, Pfleger BF. Overcoming barriers to medium-chain fatty alcohol production. Curr Opin Biotechnol 2024; 85:103063. [PMID: 38219523 PMCID: PMC10922944 DOI: 10.1016/j.copbio.2023.103063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 01/16/2024]
Abstract
Medium-chain fatty alcohols (mcFaOHs) are aliphatic primary alcohols containing six to twelve carbons that are widely used in materials, pharmaceuticals, and cosmetics. Microbial biosynthesis has been touted as a route to less-abundant chain-length molecules and as a sustainable alternative to current petrochemical processes. Several metabolic engineering strategies for producing mcFaOHs have been demonstrated in the literature, yet processes continue to suffer from poor selectivity and mcFaOH toxicity, leading to reduced titers, rates, and yields of the desired compounds. This opinion examines the current state of microbial mcFaOH biosynthesis, summarizing engineering efforts to tailor selectivity and improve product tolerance by implementing engineering strategies that circumvent or overcome mcFaOH toxicity.
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Affiliation(s)
- Yun Su
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Anna M Mangus
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - William T Cordell
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
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11
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Kato J, Matsuo T, Takemura K, Kato S, Fujii T, Wada K, Nakamichi Y, Watanabe M, Aoi Y, Morita T, Murakami K, Nakashimada Y. Isopropanol production via the thermophilic bioconversion of sugars and syngas using metabolically engineered Moorella thermoacetica. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:13. [PMID: 38281982 PMCID: PMC10823632 DOI: 10.1186/s13068-024-02460-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/11/2024] [Indexed: 01/30/2024]
Abstract
BACKGROUND Isopropanol (IPA) is a commodity chemical used as a solvent or raw material for polymeric products, such as plastics. Currently, IPA production depends largely on high-CO2-emission petrochemical methods that are not sustainable. Therefore, alternative low-CO2 emission methods are required. IPA bioproduction using biomass or waste gas is a promising method. RESULTS Moorella thermoacetica, a thermophilic acetogenic microorganism, was genetically engineered to produce IPA. A metabolic pathway related to acetone reduction was selected, and acetone conversion to IPA was achieved via the heterologous expression of secondary alcohol dehydrogenase (sadh) in the thermophilic bacterium. sadh-expressing strains were combined with acetone-producing strains, to obtain an IPA-producing strain. The strain produced IPA as a major product using hexose and pentose sugars as substrates (81% mol-IPA/mol-sugar). Furthermore, IPA was produced from CO, whereas acetate was an abundant byproduct. Fermentation using syngas containing both CO and H2 resulted in higher IPA production at the specific rate of 0.03 h-1. The supply of reducing power for acetone conversion from the gaseous substrates was examined by supplementing acetone to the culture, and the continuous and rapid conversion of acetone to IPA showed a sufficient supply of NADPH for Sadh. CONCLUSIONS The successful engineering of M. thermoacetica resulted in high IPA production from sugars. M. thermoacetica metabolism showed a high capacity for acetone conversion to IPA in the gaseous substrates, indicating acetone production as the bottleneck in IPA production for further improving the strain. This study provides a platform for IPA production via the metabolic engineering of thermophilic acetogens.
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Affiliation(s)
- Junya Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8530, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima, 739-0046, Japan
| | - Takeshi Matsuo
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8530, Japan
| | - Kaisei Takemura
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8530, Japan
| | - Setsu Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8530, Japan
| | - Tatsuya Fujii
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima, 739-0046, Japan
| | - Keisuke Wada
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Yusuke Nakamichi
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima, 739-0046, Japan
| | - Masahiro Watanabe
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima, 739-0046, Japan
| | - Yoshiteru Aoi
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8530, Japan
| | - Tomotake Morita
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima, 739-0046, Japan
| | - Katsuji Murakami
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima, 739-0046, Japan
| | - Yutaka Nakashimada
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8530, Japan.
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12
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Millgaard M, Bidart GN, Pogrebnyakov I, Nielsen AT, Welner DH. An improved integrative GFP-based vector for genetic engineering of Parageobacillus thermoglucosidasius facilitates the identification of a key sporulation regulator. AMB Express 2023; 13:44. [PMID: 37154828 PMCID: PMC10167077 DOI: 10.1186/s13568-023-01544-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 04/05/2023] [Indexed: 05/10/2023] Open
Abstract
Parageobacillus thermoglucosidasius is a thermophilic Gram-positive bacterium, which is a promising host organism for sustainable bio-based production processes. However, to take full advantage of the potential of P. thermoglucosidasius, more efficient tools for genetic engineering are required. The present study describes an improved shuttle vector, which speeds up recombination-based genomic modification by incorporating a thermostable sfGFP variant into the vector backbone. This additional selection marker allows for easier identification of recombinants, thereby removing the need for several culturing steps. The novel GFP-based shuttle is therefore capable of facilitating faster metabolic engineering of P. thermoglucosidasius through genomic deletion, integration, or exchange. To demonstrate the efficiency of the new system, the GFP-based vector was utilised for deletion of the spo0A gene in P. thermoglucosidasius DSM2542. This gene is known to be a key regulator of sporulation in Bacillus subtilis, and it was therefore hypothesised that the deletion of spo0A in P. thermoglucosiadius would produce an analogous sporulation-inhibited phenotype. Subsequent analyses of cell morphology and culture heat resistance suggests that the P. thermoglucosidasius ∆spo0A strain is sporulation-deficient. This strain may be an excellent starting point for future cell factory engineering of P. thermoglucosidasius, as the formation of endospores is normally not a desired trait in large-scale production.
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Affiliation(s)
- Marie Millgaard
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Kemitorvet, 2800, Kgs. Lyngby, Denmark
| | - Gonzalo Nahuel Bidart
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Kemitorvet, 2800, Kgs. Lyngby, Denmark
| | - Ivan Pogrebnyakov
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Kemitorvet, 2800, Kgs. Lyngby, Denmark
| | - Alex Toftgaard Nielsen
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Kemitorvet, 2800, Kgs. Lyngby, Denmark.
| | - Ditte Hededam Welner
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Kemitorvet, 2800, Kgs. Lyngby, Denmark.
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13
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Takemura K, Kato J, Kato S, Fujii T, Wada K, Iwasaki Y, Aoi Y, Matsushika A, Morita T, Murakami K, Nakashimada Y. Enhancing acetone production from H 2 and CO 2 using supplemental electron acceptors in an engineered Moorella thermoacetica. J Biosci Bioeng 2023:S1389-1723(23)00112-3. [PMID: 37100649 DOI: 10.1016/j.jbiosc.2023.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/08/2023] [Accepted: 04/02/2023] [Indexed: 04/28/2023]
Abstract
Acetogens grow autotrophically and use hydrogen (H2) as the energy source to fix carbon dioxide (CO2). This feature can be applied to gas fermentation, contributing to a circular economy. A challenge is the gain of cellular energy from H2 oxidation, which is substantially low, especially when acetate formation coupled with ATP production is diverted to other chemicals in engineered strains. Indeed, an engineered strain of the thermophilic acetogen Moorella thermoacetica that produces acetone lost autotrophic growth on H2 and CO2. We aimed to recover autotrophic growth and enhance acetone production, in which ATP production was assumed to be a limiting factor, by supplementing with electron acceptors. Among the four selected electron acceptors, thiosulfate and dimethyl sulfoxide (DMSO) enhanced both bacterial growth and acetone titers. DMSO was the most effective and was further analyzed. We showed that DMSO supplementation enhanced intracellular ATP levels, leading to increased acetone production. Although DMSO is an organic compound, it functions as an electron acceptor, not a carbon source. Thus, supplying electron acceptors is a potential strategy to complement the low ATP production caused by metabolic engineering and to improve chemical production from H2 and CO2.
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Affiliation(s)
- Kaisei Takemura
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan
| | - Junya Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan
| | - Setsu Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan
| | - Tatsuya Fujii
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima 739-0046, Japan
| | - Keisuke Wada
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Yuki Iwasaki
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima 739-0046, Japan
| | - Yoshiteru Aoi
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan
| | - Akinori Matsushika
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan; National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima 739-0046, Japan
| | - Tomotake Morita
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Katsuji Murakami
- National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashihiroshima, Hiroshima 739-0046, Japan
| | - Yutaka Nakashimada
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan.
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14
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Evaluation of Laminaria Digitata Hydrolysate for the Production of Bioethanol and Butanol by Fermentation. FERMENTATION 2023. [DOI: 10.3390/fermentation9010059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Seaweeds (macroalgae) are gaining attention as potential sustainable feedstock for the production of fuels and chemicals. This comparative study focuses on the characterization of the microbial production of alcohols from fermentable carbohydrates in the hydrolysate of the macroalgae Laminaria digitata as raw material. The potential of a hydrolysate as a carbon source for the production of selected alcohols was tested, using three physiologically different fermentative microbes, in two main types of processes. For the production of ethanol, Saccharomyces cerevisiae was used as a benchmark microorganism and compared with the strictly anaerobic thermophile Thermoanaerobacterium strain AK17. For mixed production of acetone/isopropanol, butanol, and ethanol (A/IBE), three strictly anaerobic Clostridium strains were compared. All strains grew well on the hydrolysate, and toxicity constraints were not observed, but fermentation performance and product profiles were shown to be both condition- and strain-specific. S. cerevisiae utilized only glucose for ethanol formation, while strain AK17 utilized glucose, mannitol, and parts of the glucan oligosaccharides. The clostridia strains tested showed different nutrient requirements, and were able to utilize glucan, mannitol, and organic acids in the hydrolysate. The novelty of this study embodies the application of different inoculates for fermenting a common brown seaweed found in the northern Atlantic Ocean. It provides important information on the fermentation properties of different microorganisms and pinpoints the value of carbon source utilization when selecting microbes for efficient bioconversion into biofuel and chemical products of interest.
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15
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Ariaeenejad S, Motamedi E, Kavousi K, Ghasemitabesh R, Goudarzi R, Salekdeh GH, Zolfaghari B, Roy S. Enhancing the ethanol production by exploiting a novel metagenomic-derived bifunctional xylanase/β-glucosidase enzyme with improved β-glucosidase activity by a nanocellulose carrier. Front Microbiol 2023; 13:1056364. [PMID: 36687660 PMCID: PMC9845577 DOI: 10.3389/fmicb.2022.1056364] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 11/21/2022] [Indexed: 01/06/2023] Open
Abstract
Some enzymes can catalyze more than one chemical conversion for which they are physiologically specialized. This secondary function, which is called underground, promiscuous, metabolism, or cross activity, is recognized as a valuable feature and has received much attention for developing new catalytic functions in industrial applications. In this study, a novel bifunctional xylanase/β-glucosidase metagenomic-derived enzyme, PersiBGLXyn1, with underground β-glucosidase activity was mined by in-silico screening. Then, the corresponding gene was cloned, expressed and purified. The PersiBGLXyn1 improved the degradation efficiency of organic solvent pretreated coffee residue waste (CRW), and subsequently the production of bioethanol during a separate enzymatic hydrolysis and fermentation (SHF) process. After characterization, the enzyme was immobilized on a nanocellulose (NC) carrier generated from sugar beet pulp (SBP), which remarkably improved the underground activity of the enzyme up to four-fold at 80°C and up to two-fold at pH 4.0 compared to the free one. The immobilized PersiBGLXyn1 demonstrated 12 to 13-fold rise in half-life at 70 and 80°C for its underground activity. The amount of reducing sugar produced from enzymatic saccharification of the CRW was also enhanced from 12.97 g/l to 19.69 g/l by immobilization of the enzyme. Bioethanol production was 29.31 g/l for free enzyme after 72 h fermentation, while the immobilized PersiBGLXyn1 showed 51.47 g/l production titre. Overall, this study presented a cost-effective in-silico metagenomic approach to identify novel bifunctional xylanase/β-glucosidase enzyme with underground β-glucosidase activity. It also demonstrated the improved efficacy of the underground activities of the bifunctional enzyme as a promising alternative for fermentable sugars production and subsequent value-added products.
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Affiliation(s)
- Shohreh Ariaeenejad
- Department of Systems and Synthetic Biology, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran,*Correspondence: Shohreh Ariaeenejad, ;
| | - Elaheh Motamedi
- Department of Nanotechnology, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran
| | - Kaveh Kavousi
- Laboratory of Complex Biological Systems and Bioinformatics (CBB), Department of Bioinformatics, Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Rezvaneh Ghasemitabesh
- Department of Systems and Synthetic Biology, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran
| | - Razieh Goudarzi
- Department of Systems and Synthetic Biology, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran
| | - Ghasem Hosseini Salekdeh
- Department of Systems and Synthetic Biology, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran,Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia,Ghasem Hosseini Salekdeh,
| | - Behrouz Zolfaghari
- Department of Integrated Art and Sciences, Faculty of Education, Waseda University, Tokyo, Japan
| | - Swapnoneel Roy
- School of Computing, University of North Florida, Jacksonville, FL, United States
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16
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Li X, Zhang W, Zhong XR, Han HX, Dong B. Genome sequencing analysis of a novel thermophilic strain Geobacillus sp. CX412. Front Microbiol 2022; 13:1035311. [PMID: 36439810 PMCID: PMC9693769 DOI: 10.3389/fmicb.2022.1035311] [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: 09/02/2022] [Accepted: 10/10/2022] [Indexed: 09/11/2024] Open
Abstract
The thermophilic spore-forming strain Geobacillus sp. CX412 was isolated from hot spring soil in Tengchong City, Yunnan Province, China. We sequenced the complete genome of Geobacillus sp. CX412 using PacBio SMRT Sequencing. Genome-scale phylogenetic analysis and average nucleotide identity (ANI) results indicated that Geobacillus sp. CX412 is a novel species in the genus Geobacillus. The metabolic potential of Geobacillus sp. CX412 based on COG, KEGG, and CAZymes analysis demonstrated that Geobacillus sp. CX412 was a highly adaptable strain with an unusually high number of 73 annotated transposons in the genome, which is relatively rare in Geobacillus. Compared with the near-derived strains, it was found that Geobacillus sp. CX412 has the unique β-lactam resistance and more active metabolism (more than 50.5-100.1%). Additionally, its genome encodes glycoside hydrolases and other genes related to lignocellulose breakdown, suggesting that Geobacillus sp. CX412 has a considerable biomass degradation potential. Thus, Geobacillus sp. CX412 is a new thermophilic bacterial species that add to the increasing repertoire of known lignocellulose degraders.
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Affiliation(s)
- Xin Li
- School of Environmental Science and Engineering, Tongji University, Shanghai, China
| | - Wei Zhang
- School of Environmental Science and Engineering, Tongji University, Shanghai, China
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, China
| | - Xin-Ru Zhong
- School of Environmental Science and Engineering, Tongji University, Shanghai, China
| | - Hao-Xuan Han
- School of Environmental Science and Engineering, Tongji University, Shanghai, China
| | - Bin Dong
- School of Environmental Science and Engineering, Tongji University, Shanghai, China
- YANGTZE Eco-Environment Engineering Research Center, China Three Gorges Corporation, Beijing, China
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17
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Thermophilic Water Gas Shift Reaction at High Carbon Monoxide and Hydrogen Partial Pressures in Parageobacillus thermoglucosidasius KP1013. FERMENTATION 2022. [DOI: 10.3390/fermentation8110596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The facultatively anaerobic Parageobacillus thermoglucosidasius oxidizes carbon monoxide to produce hydrogen via the water gas shift (WGS) reaction. In the current work, we examined the influence of carbon monoxide (CO) and hydrogen (H2) on the WGS reaction in the thermophilic P. thermoglucosidasius by cultivating two hydrogenogenic strains under varying CO and H2 compositions. Microbial growth and dynamics of the WGS reaction were monitored by evaluating parameters such as pressure, headspace composition, metabolic intermediates, pH, and optical density. Our analyses revealed that compared to the previously studied P. thermoglucosidasius strains, the strain KP1013 demonstrated higher CO tolerance and improved WGS reaction kinetics. Under anaerobic conditions, the lag phase before the WGS reaction shortened to 8 h, with KP1013 showing no hydrogen-induced product inhibition at hydrogen partial pressures up to 1.25 bar. The observed lack of product inhibition and the reduced lag phase of the WGS reaction support the possibility of establishing an industrial process for biohydrogen production with P. thermoglucosidasius.
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18
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Hoppert L, Kölling R, Einfalt D. Investigation of stress tolerance of Pichia kudriavzevii for high gravity bioethanol production from steam-exploded wheat straw hydrolysate. BIORESOURCE TECHNOLOGY 2022; 364:128079. [PMID: 36220531 DOI: 10.1016/j.biortech.2022.128079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/01/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
This study investigated a newly isolated thermotolerant strain of Pichia kudriavzevii with respect to its stress tolerance and fermentation performance. Response surface methodology was applied to evaluate the combined effects of furfural, osmotic and thermal stress on ethanol yield. The proposed model shows that P. kudriavzevii has a natural resistance against multiple stress factors. Further evolutionary adaptation of the isolated strain in lignocellulosic hydrolysates improved the ethanol yield by ≥ 24 %. The adapted strain HYPK213_ELA was able to produce ethanol from wheat straw hydrolysates at a high solid loading of 37 %ww-1 at 40 °C and anaerobic conditions. The highest ethanol concentration of 56.8 ± 1.0 gL-1 was reached at 40°C with an inoculum size of 2.5 × 106cellsmL-1. The results show that Pichia kudriavzevii has the potential to enable high gravity bioethanol production under conditions where most yeast strains are unable to grow.
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Affiliation(s)
- Luis Hoppert
- Institute of Food Science and Biotechnology, Yeast Genetics and Fermentation Technology, University of Hohenheim, Garbenstraße 23, 70599 Stuttgart, Germany.
| | - Ralf Kölling
- Institute of Food Science and Biotechnology, Yeast Genetics and Fermentation Technology, University of Hohenheim, Garbenstraße 23, 70599 Stuttgart, Germany
| | - Daniel Einfalt
- Institute of Food Science and Biotechnology, Yeast Genetics and Fermentation Technology, University of Hohenheim, Garbenstraße 23, 70599 Stuttgart, Germany
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Kobayashi S, Kato J, Wada K, Takemura K, Kato S, Fujii T, Iwasaki Y, Aoi Y, Morita T, Matsushika A, Murakami K, Nakashimada Y. Reversible Hydrogenase Activity Confers Flexibility to Balance Intracellular Redox in Moorella thermoacetica. Front Microbiol 2022; 13:897066. [PMID: 35633713 PMCID: PMC9133594 DOI: 10.3389/fmicb.2022.897066] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Hydrogen (H2) converted to reducing equivalents is used by acetogens to fix and metabolize carbon dioxide (CO2) to acetate. The utilization of H2 enables not only autotrophic growth, but also mixotrophic metabolism in acetogens, enhancing carbon utilization. This feature seems useful, especially when the carbon utilization efficiency of organic carbon sources is lowered by metabolic engineering to produce reduced chemicals, such as ethanol. The potential advantage was tested using engineered strains of Moorella thermoacetica that produce ethanol. By adding H2 to the fructose-supplied culture, the engineered strains produced increased levels of acetate, and a slight increase in ethanol was observed. The utilization of a knockout strain of the major acetate production pathway, aimed at increasing the carbon flux to ethanol, was unexpectedly hindered by H2-mediated growth inhibition in a dose-dependent manner. Metabolomic analysis showed a significant increase in intracellular NADH levels due to H2 in the ethanol-producing strain. Higher NADH level was shown to be the cause of growth inhibition because the decrease in NADH level by dimethyl sulfoxide (DMSO) reduction recovered the growth. When H2 was not supplemented, the intracellular NADH level was balanced by the reversible electron transfer from NADH oxidation to H2 production in the ethanol-producing strain. Therefore, reversible hydrogenase activity confers the ability and flexibility to balance the intracellular redox state of M. thermoacetica. Tuning of the redox balance is required in order to benefit from H2-supplemented mixotrophy, which was confirmed by engineering to produce acetone.
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Affiliation(s)
- Shunsuke Kobayashi
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Junya Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Keisuke Wada
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Kaisei Takemura
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Setsu Kato
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Tatsuya Fujii
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Japan
| | - Yuki Iwasaki
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Japan
| | - Yoshiteru Aoi
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Tomotake Morita
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Akinori Matsushika
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Japan
| | - Katsuji Murakami
- National Institute of Advanced Industrial Science and Technology (AIST), Higashihiroshima, Japan
| | - Yutaka Nakashimada
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
- *Correspondence: Yutaka Nakashimada,
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20
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Svetlitchnyi VA, Svetlichnaya TP, Falkenhan DA, Swinnen S, Knopp D, Läufer A. Direct conversion of cellulose to L-lactic acid by a novel thermophilic Caldicellulosiruptor strain. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:44. [PMID: 35501875 PMCID: PMC9063331 DOI: 10.1186/s13068-022-02137-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 04/14/2022] [Indexed: 11/18/2022]
Abstract
Background Consolidated bioprocessing (CBP) of lignocellulosic biomass to l-lactic acid using thermophilic cellulolytic/hemicellulolytic bacteria provides a promising solution for efficient lignocellulose conversion without the need for additional cellulolytic/hemicellulolytic enzymes. Most studies on the mesophilic and thermophilic CBP of lignocellulose to lactic acid concentrate on cultivation of non-cellulolytic mesophilic and thermophilic bacteria at temperatures of 30–55 °C with external addition of cellulases/hemicellulases for saccharification of substrates. Results l-Lactic acid was generated by fermenting microcrystalline cellulose or lignocellulosic substrates with a novel thermophilic anaerobic bacterium Caldicellulosiruptor sp. DIB 104C without adding externally produced cellulolytic/hemicellulolytic enzymes. Selection of this novel bacterium strain for lactic acid production is described as well as the adaptive evolution towards increasing the l-lactic acid concentration from 6 to 70 g/l on microcrystalline cellulose. The evolved strains grown on microcrystalline cellulose show a maximum lactic acid production rate of 1.0 g/l*h and a lactic acid ratio in the total organic fermentation products of 96 wt%. The enantiomeric purity of the l-lactic acid generated is 99.4%. In addition, the lactic acid production by these strains on several other types of cellulose and lignocellulosic feedstocks is also reported. Conclusions The evolved strains originating from Caldicellulosiruptor sp. DIB 104C were capable of producing unexpectedly large amounts of l-lactic acid from microcrystalline cellulose in fermenters. These strains produce l-lactic acid also from lignocellulosic feedstocks and thus represent an ideal starting point for development of a highly integrated commercial l-lactic acid production process from such feedstocks.
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Affiliation(s)
| | | | | | - Steve Swinnen
- BluCon Biotech GmbH, Nattermannallee 1, 50829, Cologne, Germany
| | - Daniela Knopp
- BluCon Biotech GmbH, Nattermannallee 1, 50829, Cologne, Germany
| | - Albrecht Läufer
- BluCon Biotech GmbH, Nattermannallee 1, 50829, Cologne, Germany
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21
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Synergy of Cellulase Systems between Acetivibrio thermocellus and Thermoclostridium stercorarium in Consolidated-Bioprocessing for Cellulosic Ethanol. Microorganisms 2022; 10:microorganisms10030502. [PMID: 35336078 PMCID: PMC8951355 DOI: 10.3390/microorganisms10030502] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/21/2022] [Accepted: 02/21/2022] [Indexed: 11/18/2022] Open
Abstract
Anaerobes harbor some of the most efficient biological machinery for cellulose degradation, especially thermophilic bacteria, such as Acetivibrio thermocellus and Thermoclostridium stercorarium, which play a fundamental role in transferring lignocellulose into ethanol through consolidated bioprocessing (CBP). In this study, we compared activities of two cellulase systems under varying kinds of hemicellulose and cellulose. A. thermocellus was identified to contribute specifically to cellulose hydrolysis, whereas T. stercorarium contributes to hemicellulose hydrolysis. The two systems were assayed in various combinations to assess their synergistic effects using cellulose and corn stover as the substrates. Their maximum synergy degrees on cellulose and corn stover were, respectively, 1.26 and 1.87 at the ratio of 3:2. Furthermore, co-culture of these anaerobes on the mixture of cellulose and xylan increased ethanol concentration from 21.0 to 40.4 mM with a high cellulose/xylan-to-ethanol conversion rate of up to 20.7%, while the conversion rates of T. stercorarium and A. thermocellus monocultures were 19.3% and 15.2%. The reason is that A. thermocellus had the ability to rapidly degrade cellulose while T. stercorarium co-utilized both pentose and hexose, the metabolites of cellulose degradation, to produce ethanol. The synergistic effect of cellulase systems and metabolic pathways in A. thermocellus and T. stercorarium provides a novel strategy for the design, selection, and optimization of ethanol production from cellulosic biomass through CBP.
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Wang Y, Wang J, Zhang Z, Yang J, Turunen O, Xiong H. High-temperature behavior of hyperthermostable Thermotoga maritima xylanase XYN10B after designed and evolved mutations. Appl Microbiol Biotechnol 2022; 106:2017-2027. [PMID: 35171339 DOI: 10.1007/s00253-022-11823-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 01/29/2022] [Accepted: 02/05/2022] [Indexed: 11/24/2022]
Abstract
A hyperthermostable xylanase XYN10B from Thermotoga maritima (PDB code 1VBR, GenBank accession number KR078269) was subjected to site-directed and error-prone PCR mutagenesis. From the selected five mutants, the two site-directed mutants (F806H and F806V) showed a 3.3-3.5-fold improved enzyme half-life at 100 °C. The mutant XYNA generated by error-prone PCR showed slightly improved stability at 100 °C and a lower Km. In XYNB and XYNC, the additional mutations over XYNA decreased the thermostability and temperature optimum, while elevating the Km. In XYNC, two large side-chains were introduced into the protein's interior. Micro-differential scanning calorimetry (DSC) showed that the melting temperature (Tm) dropped in XYNB and XYNC from 104.9 °C to 93.7 °C and 78.6 °C, respectively. The detrimental mutations showed that extremely thermostable enzymes can tolerate quite radical mutations in the protein's interior and still retain high thermostability. The analysis of mutations (F806H and F806V) in a hydrophobic area lining the substrate-binding region indicated that active site hydrophobicity is important for high activity at extreme temperatures. Although polar His at 806 provided higher stability, the hydrophobic Phe at 806 provided higher activity than His. This study generates an understanding of how extreme thermostability and high activity are formed in GH10 xylanases. KEY POINTS: • Characterization and molecular dynamics simulations of TmXYN10B and its mutants • Explanation of structural stability of GH10 xylanase.
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Affiliation(s)
- Yawei Wang
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430048, China
| | - Jing Wang
- College of Life Science, South-central University for Nationalities, Wuhan, 430074, China
| | - Zhongqiang Zhang
- College of Life Science, South-central University for Nationalities, Wuhan, 430074, China
| | - Jiangke Yang
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430048, China
| | - Ossi Turunen
- School of Forest Sciences, University of Eastern Finland, FI-80101, Joensuu, Finland.
| | - Hairong Xiong
- College of Life Science, South-central University for Nationalities, Wuhan, 430074, China.
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Kazemi Shariat Panahi H, Dehhaghi M, Dehhaghi S, Guillemin GJ, Lam SS, Aghbashlo M, Tabatabaei M. Engineered bacteria for valorizing lignocellulosic biomass into bioethanol. BIORESOURCE TECHNOLOGY 2022; 344:126212. [PMID: 34715341 DOI: 10.1016/j.biortech.2021.126212] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/17/2021] [Accepted: 10/20/2021] [Indexed: 06/13/2023]
Abstract
Appropriate bioprocessing of lignocellulosic materials into ethanol could address the world's insatiable appetite for energy while mitigating greenhouse gases. Bioethanol is an ideal gasoline extender and is widely used in many countries in blended form with gasoline at specific ratios to improve fuel characteristics and engine performance. Although the bioethanol production industry has long been operational, finding a suitable microbial agent for the efficient conversion of lignocelluloses is still an active field of study. Among available microbial candidates, engineered bacteria may be promising ethanol producers while may show other desired traits such as thermophilic nature and high ethanol tolerance. This review provides the current knowledge on the introduction, overexpression, and deletion of the genes that have been performed in bacterial hosts to achieve higher ethanol yield, production rate and titer, and tolerance. The constraints and possible solutions and economic feasibility of the processes utilizing such engineered strains are also discussed.
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Affiliation(s)
- Hamed Kazemi Shariat Panahi
- Henan Province Engineering Research Center for Forest Biomass Value-added Products, School of Forestry, Henan Agricultural University, Zhengzhou, Henan, 450002, China; Neuroinflammation Group, Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW, Australia; Biofuel Research Team (BRTeam), Terengganu, Malaysia
| | - Mona Dehhaghi
- Neuroinflammation Group, Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW, Australia; Biofuel Research Team (BRTeam), Terengganu, Malaysia; PANDIS.org, Australia
| | - Somayeh Dehhaghi
- Department of Agricultural Extension and Education, Tarbiat Modares University, Tehran 14115-336, Iran
| | - Gilles J Guillemin
- Neuroinflammation Group, Department of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW, Australia; PANDIS.org, Australia
| | - Su Shiung Lam
- Henan Province Engineering Research Center for Forest Biomass Value-added Products, School of Forestry, Henan Agricultural University, Zhengzhou, Henan, 450002, China; Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia.
| | - Mortaza Aghbashlo
- Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Meisam Tabatabaei
- Henan Province Engineering Research Center for Forest Biomass Value-added Products, School of Forestry, Henan Agricultural University, Zhengzhou, Henan, 450002, China; Biofuel Research Team (BRTeam), Terengganu, Malaysia; Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia; Microbial Biotechnology Department, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
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Chen L, Wang M, Zhang Z, Feng Y. Application of electric potential improves ethanol production from xylose by active sludge. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:215. [PMID: 34789328 PMCID: PMC8596957 DOI: 10.1186/s13068-021-02065-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 10/29/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Low-cost raw materials such as lignocellulosic materials have been utilized in second-generation ethanol production process. However, the sequential and slow conversion of xylose into target products remains one of the main challenges for realizing efficient industrial lignocellulosic biorefinery. RESULTS By applying different constant potentials to different microbial electrolysis cells with xylose as the sole carbon source, we analyzed the output of metabolites, microbial community structures, electron flow, and carbon flow in the process of xylose electro-fermentation by domesticated activated sludge. The bioreactors produced currents when applying positive potentials. The peak currents of the + 0.242 V, + 0.542 V and + 0.842 V reactors were 0.96 × 10-6 A, 3.36 × 10-6 A and 6.43 × 10-6 A, respectively. The application of potentials promoted the xylose consumption, and the maximum consumption rate in the + 0.542 V reactor was 95.5%, which was 34.8 times that of the reactor without applied potential. The potential application also promoted the production of ethanol and acetate. The maximum ethanol yield (0.652 mol mol-1 xylose) was obtained in the + 0.842 V reactor. The maximum acetate concentration (1,874 µmol L-1) was observed in the + 0.842 V reactor. The optimal potential for ethanol production was + 0.842 V with the maximum ethanol yield and energy saving. The application of positive potential caused the microorganisms to carry out ethanol fermentation, and the application of negative potential forced the microorganisms to carry out acetic fermentation. The potential application changed the diversity and community structure of microorganisms in the reactors, and the two most significantly changed families were Paenibacillaceae and Bacillaceae. CONCLUSION The constructed microbial electrolysis cells with different potentials obtained better production yield and selectivity compared with the reactor without applied potential. Our work provides strategies for the subsequent fermentation processes with different needs.
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Affiliation(s)
- Lei Chen
- School of Life Science, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Mingpeng Wang
- School of Life Science, Qufu Normal University, Qufu, 273165, People's Republic of China.
| | - Zhaojie Zhang
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, 82071, USA
| | - Yujie Feng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, People's Republic of China.
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Makowski K, Leszczewicz M, Broncel N, Lipińska-Zubrycka L, Głębski A, Komorowski P, Walkowiak B. Isolation, Biochemical Characterisation and Identification of Thermotolerant and Cellulolytic Paenibacillus lactis and Bacillus licheniformis. Food Technol Biotechnol 2021; 59:325-336. [PMID: 34759764 PMCID: PMC8542176 DOI: 10.17113/ftb.59.03.21.7096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 06/24/2021] [Indexed: 11/12/2022] Open
Abstract
Research background Cellulose is an ingredient of waste materials that can be converted to other valuable substances. This is possible provided that the polymer molecule is degraded to smaller particles and used as a carbon source by microorganisms. Because of the frequently applied methods of pretreatment of lignocellulosic materials, the cellulases derived from thermophilic microorganisms are particularly desirable. Experimental approach We were looking for cellulolytic microorganisms able to grow at 50 °C and we described their morphological features and biochemical characteristics based on carboxymethyl cellulase (CMCase) activity and the API® ZYM system. The growth curves during incubation at 50 °C were examined using the BioLector® microbioreactor. Results and conclusions Forty bacterial strains were isolated from fermenting hay, geothermal karst spring, hot spring and geothermal pond at 50 °C. The vast majority of the bacteria were Gram-positive and rod-shaped with the maximum growth temperature of at least 50 °C. We also demonstrated a large diversity of biochemical characteristics among the microorganisms. The CMCase activity was confirmed in 27 strains. Hydrolysis capacities were significant in bacterial strains: BBLN1, BSO6, BSO10, BSO13 and BSO14, and reached 2.74, 1.62, 1.30, 1.38 and 8.02 respectively. Rapid and stable growth was observed, among others, for BBLN1, BSO10, BSO13 and BSO14. The strains fulfilled the selection conditions and were identified based on the 16S rDNA sequences. BBLN1, BSO10, BSO13 were classified as Bacillus licheniformis, whereas BSO14 as Paenibacillus lactis. Novelty and scientific contribution We described cellulolytic activity and biochemical characteristics of many bacteria isolated from hot environments. We are also the first to report the cellulolytic activity of thermotolerant P. lactis. Described strains can be a source of new thermostable cellulases, which are extremely desirable in various branches of circular bioeconomy.
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Affiliation(s)
- Krzysztof Makowski
- Industrial Biotechnology Laboratory, Bionanopark Ltd., Dubois 114/116, 93-465 Lodz, Poland.,Biotechnika, Tymienieckiego 25, 90-350 Lodz, Poland
| | - Martyna Leszczewicz
- Industrial Biotechnology Laboratory, Bionanopark Ltd., Dubois 114/116, 93-465 Lodz, Poland
| | - Natalia Broncel
- Industrial Biotechnology Laboratory, Bionanopark Ltd., Dubois 114/116, 93-465 Lodz, Poland
| | - Lidia Lipińska-Zubrycka
- Industrial Biotechnology Laboratory, Bionanopark Ltd., Dubois 114/116, 93-465 Lodz, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Adrian Głębski
- Industrial Biotechnology Laboratory, Bionanopark Ltd., Dubois 114/116, 93-465 Lodz, Poland
| | - Piotr Komorowski
- Molecular and Nanostructural Biophysics Laboratory, Bionanopark Ltd., Dubois 114/116, 93-465 Lodz, Poland.,Institute of Materials Science and Engineering, Lodz University of Technology, Stefanowskiego 1/15, 90-537 Lodz, Poland
| | - Bogdan Walkowiak
- Molecular and Nanostructural Biophysics Laboratory, Bionanopark Ltd., Dubois 114/116, 93-465 Lodz, Poland.,Institute of Materials Science and Engineering, Lodz University of Technology, Stefanowskiego 1/15, 90-537 Lodz, Poland
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Zalma SA, El-Sharoud WM. Diverse thermophilic Bacillus species with multiple biotechnological activities are associated within the Egyptian soil and compost samples. Sci Prog 2021; 104:368504211055277. [PMID: 34816770 PMCID: PMC10461379 DOI: 10.1177/00368504211055277] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Thermophilic strains of Bacillus can express enzymes of higher thermal stability, which allows carrying out industrial fermentations under higher temperatures. This lowers the contamination potential, accelerates mixing rates and facilitates the recovery of fermentation end products. The present study was thus designed to isolate and characterize thermophilic Bacillus cultures from soil and compost samples. Forty-two thermophilic Bacillus isolates could be identified employing morphological, physiological and the 16S rRNA gene sequencing analyses. The isolates showed a high degree of biological diversity involving 13 Bacillus species and 1 subspecies but were dominated by Bacillus licheniformis. Phylogenetic analysis of B. licheniformis isolates based on the DNA sequencing of gyrA and rpoB genes presented them in two main genetic groups. Isolates of five thermophilic species including B. licheniformis, Bacillus altitudinis, Bacillus paralicheniformis, Bacillus subtilis and Bacillus thermoamylovorans showed multiple activities to degrade all of cellulose, hemicellulose and lignin. Those multifunctional thermophilic Bacillus isolates can be harnessed in the degradation of plant wastes for the production of biofuels and compost.
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Affiliation(s)
- SA Zalma
- Food Safety and Microbial
Physiology Lab, Faculty of Agriculture, Mansoura University, Mansoura, Egypt
| | - WM El-Sharoud
- Food Safety and Microbial
Physiology Lab, Faculty of Agriculture, Mansoura University, Mansoura, Egypt
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Banu JR, Kumar G, Chattopadhyay I. Management of microbial enzymes for biofuels and biogas production by using metagenomic and genome editing approaches. 3 Biotech 2021; 11:429. [PMID: 34603908 DOI: 10.1007/s13205-021-02962-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 08/04/2021] [Indexed: 12/16/2022] Open
Abstract
Non-renewable fossil fuels such as bitumen, coal, natural gas, oil shale, and petroleum are depleting over the world owing to unrestricted consumption. Biofuels such as biodiesel, biobutanol, bioethanol, and biogas are considered an eco-friendly and cost-effective alternatives of fossil fuels. For energy sustainability, the production of advanced biofuels is required. The advancement of genetic and metabolic engineering in microbial cells played a significant contribution to biofuels overproduction. Essential approaches such as next-generation sequencing technologies and CRISPR/Cas9-mediated genome editing of microbial cells are required for the mass manufacture of biofuels globally. Advanced "omics" approaches are used to construct effective microorganisms for biofuels manufacturing. A new investigation is required to augment the production of lignocellulosic-based biofuels with minimal use of energy. Advanced areas of metabolic engineering are introduced in the manufacture of biofuels by the use of engineered microbial strains. Genetically modified microorganisms are used for the production of biofuels in large quantities at a low-cost.
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Affiliation(s)
- J Rajesh Banu
- Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur, Tamilnadu India
| | - Gopalakrishnan Kumar
- Faculty of Science and Technology, Institute of Chemistry, Bioscience and Environmental Engineering, University of Stavanger, Forus, Box 8600, 4036 Stavanger, Norway
| | - Indranil Chattopadhyay
- Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur, Tamilnadu India
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Obergruber M, Hönig V, Jenčík J, Hájek J, Schlehöfer D, Herink T. Lignocellulosic Bioethanol and Biobutanol as a Biocomponent for Diesel Fuel. MATERIALS 2021; 14:ma14195597. [PMID: 34639994 PMCID: PMC8509815 DOI: 10.3390/ma14195597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 11/16/2022]
Abstract
In this paper, the fuel properties of mixtures of diesel fuel and ethanol and diesel fuel and butanol in the ratio of 2.5% to 30% were investigated. The physicochemical properties of the blends such as the cetane number, cetane index, density, flash point, kinematic viscosity, lubricity, CFPP, and distillation characteristics were measured, and the effect on fuel properties was evaluated. These properties were compared with the current EN 590+A1 standard to evaluate the suitability of the blends for use in unmodified engines. The alcohols were found to be a suitable bio-component diesel fuel additive. For most physicochemical properties, butanol was found to have more suitable properties than ethanol when used in diesel engines. The results show that for some properties, a butanol–diesel fuel mixture can be mixed up to a ratio of 15%. Other properties would meet the standard by a suitable choice of base diesel.
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Affiliation(s)
- Michal Obergruber
- Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 169 21 Prague, Czech Republic; (M.O.); (J.J.); (J.H.)
| | - Vladimír Hönig
- Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 169 21 Prague, Czech Republic; (M.O.); (J.J.); (J.H.)
- Correspondence: ; Tel.: +420-22438-2722
| | - Jan Jenčík
- Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 169 21 Prague, Czech Republic; (M.O.); (J.J.); (J.H.)
- ORLEN UniCRE a.s., Záluží 1, 436 70 Litvínov, Czech Republic; (D.S.); (T.H.)
| | - Jiří Hájek
- Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 169 21 Prague, Czech Republic; (M.O.); (J.J.); (J.H.)
- ORLEN UniCRE a.s., Záluží 1, 436 70 Litvínov, Czech Republic; (D.S.); (T.H.)
| | - Dominik Schlehöfer
- ORLEN UniCRE a.s., Záluží 1, 436 70 Litvínov, Czech Republic; (D.S.); (T.H.)
| | - Tomáš Herink
- ORLEN UniCRE a.s., Záluží 1, 436 70 Litvínov, Czech Republic; (D.S.); (T.H.)
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Biorefinery Gets Hot: Thermophilic Enzymes and Microorganisms for Second-Generation Bioethanol Production. Processes (Basel) 2021. [DOI: 10.3390/pr9091583] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
To mitigate the current global energy and the environmental crisis, biofuels such as bioethanol have progressively gained attention from both scientific and industrial perspectives. However, at present, commercialized bioethanol is mainly derived from edible crops, thus raising serious concerns given its competition with feed production. For this reason, lignocellulosic biomasses (LCBs) have been recognized as important alternatives for bioethanol production. Because LCBs supply is sustainable, abundant, widespread, and cheap, LCBs-derived bioethanol currently represents one of the most viable solutions to meet the global demand for liquid fuel. However, the cost-effective conversion of LCBs into ethanol remains a challenge and its implementation has been hampered by several bottlenecks that must still be tackled. Among other factors related to the challenging and variable nature of LCBs, we highlight: (i) energy-demanding pretreatments, (ii) expensive hydrolytic enzyme blends, and (iii) the need for microorganisms that can ferment mixed sugars. In this regard, thermophiles represent valuable tools to overcome some of these limitations. Thus, the aim of this review is to provide an overview of the state-of-the-art technologies involved, such as the use of thermophilic enzymes and microorganisms in industrial-relevant conditions, and to propose possible means to implement thermophiles into second-generation ethanol biorefineries that are already in operation.
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Łubkowska B, Jeżewska-Frąckowiak J, Sobolewski I, Skowron PM. Bacteriophages of Thermophilic ' Bacillus Group' Bacteria-A Review. Microorganisms 2021; 9:1522. [PMID: 34361957 PMCID: PMC8303945 DOI: 10.3390/microorganisms9071522] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/03/2021] [Accepted: 07/12/2021] [Indexed: 11/17/2022] Open
Abstract
Bacteriophages of thermophiles are of increasing interest owing to their important roles in many biogeochemical, ecological processes and in biotechnology applications, including emerging bionanotechnology. However, due to lack of in-depth investigation, they are underrepresented in the known prokaryotic virosphere. Therefore, there is a considerable potential for the discovery of novel bacteriophage-host systems in various environments: marine and terrestrial hot springs, compost piles, soil, industrial hot waters, among others. This review aims at providing a reference compendium of thermophages characterized thus far, which infect the species of thermophilic 'Bacillus group' bacteria, mostly from Geobacillus sp. We have listed 56 thermophages, out of which the majority belong to the Siphoviridae family, others belong to the Myoviridae and Podoviridae families and, apparently, a few belong to the Sphaerolipoviridae, Tectiviridae or Corticoviridae families. All of their genomes are composed of dsDNA, either linear, circular or circularly permuted. Fourteen genomes have been sequenced; their sizes vary greatly from 35,055 bp to an exceptionally large genome of 160,590 bp. We have also included our unpublished data on TP-84, which infects Geobacillus stearothermophilus (G. stearothermophilus). Since the TP-84 genome sequence shows essentially no similarity to any previously characterized bacteriophage, we have defined TP-84 as a new species in the newly proposed genus Tp84virus within the Siphoviridae family. The information summary presented here may be helpful in comparative deciphering of the molecular basis of the thermophages' biology, biotechnology and in analyzing the environmental aspects of the thermophages' effect on the thermophile community.
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Affiliation(s)
- Beata Łubkowska
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, 80-308 Gdansk, Poland; (J.J.-F.); (I.S.); (P.M.S.)
- The High School of Health in Gdansk, Pelplinska 7, 80-335 Gdansk, Poland
| | - Joanna Jeżewska-Frąckowiak
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, 80-308 Gdansk, Poland; (J.J.-F.); (I.S.); (P.M.S.)
| | - Ireneusz Sobolewski
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, 80-308 Gdansk, Poland; (J.J.-F.); (I.S.); (P.M.S.)
| | - Piotr M. Skowron
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, 80-308 Gdansk, Poland; (J.J.-F.); (I.S.); (P.M.S.)
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Lau MSH, Sheng L, Zhang Y, Minton NP. Development of a Suite of Tools for Genome Editing in Parageobacillus thermoglucosidasius and Their Use to Identify the Potential of a Native Plasmid in the Generation of Stable Engineered Strains. ACS Synth Biol 2021; 10:1739-1749. [PMID: 34197093 DOI: 10.1021/acssynbio.1c00138] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The relentless rise in the levels of atmospheric greenhouse gases caused by the exploitation of fossil fuel necessitates the development of more environmentally friendly routes to the manufacture of chemicals and fuels. The exploitation of a fermentative process that uses a thermophilic chassis represents an attractive option. Its use, however, is hindered by a dearth of genetic tools. Here we expand on those available for the engineering of the industrial chassis Parageobacillus thermoglucosidasius through the assembly and testing of a range of promoters, ribosome binding sites, reporter genes, and the implementation of CRISPR/Cas9 genome editing based on two different thermostable Cas9 nucleases. The latter were used to demonstrate that the deletion of the two native plasmids carried by P. thermoglucosidasius, pNCI001 and pNCI002, either singly or in combination, had no discernible effects on the overall phenotypic characteristics of the organism. Through the CRISPR/Cas9-mediated insertion of the gene encoding a novel fluorescent reporter, eCGP123, we showed that pNCI001 exhibited a high degree of segregational stability. As the relatively higher copy number of pNCI001 led to higher levels of eCGP123 expression than when the same gene was integrated into the chromosome, we propose that pNCI001 represents the preferred option for the integration of metabolic operons when stable commercial strains are required.
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Affiliation(s)
- Matthew S. H. Lau
- BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), Biodiscovery Institute, School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K
| | - Lili Sheng
- BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), Biodiscovery Institute, School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K
| | - Ying Zhang
- BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), Biodiscovery Institute, School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K
| | - Nigel P. Minton
- BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), Biodiscovery Institute, School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, U.K
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Effect of the age of Opuntia ficus-indica cladodes on the release of simple sugars. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.102010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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33
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Bao S, Ding X, Yu S, Xing X, Ding C. Characterization of pyruvate dehydrogenase complex E1 alpha and beta subunits of Mycoplasma synoviae. Microb Pathog 2021; 155:104851. [PMID: 33794298 DOI: 10.1016/j.micpath.2021.104851] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 03/06/2021] [Accepted: 03/13/2021] [Indexed: 01/24/2023]
Abstract
Mycoplasma synoviae (MS) is an important pathogen which causes huge economic losses to the poultry industry worldwide, and research on MS can provide the foundation for diagnosis, prevention, and treatment of MS infection. In this study, primers designed based on the sequences of pyruvate dehydrogenase complex (PDC) E1 alpha and beta subunit genes (pdhA and pdhB, respectively) of MS 53 strain(AE017245.1) in GenBank were used to amplify the pdhA and pdhB genes of MS WVU1853 strain through PCR. Subsequently, the prokaryotic expression vectors pET-28a(+)-pdhA and pET-28a(+)-pdhB were constructed and expressed in Escherichia coli BL21(DE3) cells. The recombinant proteins rMSPDHA and rMSPDHB were purified, and anti-rMSPDHA and anti-rMSPDHB sera were prepared by immunizing rabbits, respectively. Subcellular localization of PDHA and PDHB in MS cells, binding activity of rMSPDHA and rMSPDHB to chicken plasminogen (Plg) and human fibronectin (Fn), complement-dependent mycoplasmacidal assays, and adherence and adherence inhibition assays were accomplished. The results showed that PDHA and PDHB were distributed both on the surface membrane and within soluble cytosolic fractions of MS cells. The rMSPDHA and rMSPDHB presented binding activity with chicken Plg and human Fn. The rabbit anti-rMSPDHA and anti-rMSPDHB sera had distinct mycoplasmacidal efficacy in the presence of guinea pig complement, and the adherence of MS to DF-1 cells pretreated with Plg was effectively inhibited by treatment with anti-rMSPDHA or anti-rMSPDHB sera. These findings indicated that surface-associated MSPDHA and MSPDHB were adhesion-related factors of MS and that the binding between MSPDHA/MSPDHB and Plg/Fn contributed to MS adhesion to DF-1 cells.
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Affiliation(s)
- Shijun Bao
- College of Veterinary Medicine, Gansu Agricultural University, 1 Yingmencun, Lanzhou, 730070, PR China.
| | - Xiaoqin Ding
- College of Veterinary Medicine, Gansu Agricultural University, 1 Yingmencun, Lanzhou, 730070, PR China.
| | - Shengqing Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 518 Ziyue Road, Minhang District, Shanghai, 200241, PR China.
| | - Xiaoyong Xing
- College of Veterinary Medicine, Gansu Agricultural University, 1 Yingmencun, Lanzhou, 730070, PR China.
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 518 Ziyue Road, Minhang District, Shanghai, 200241, PR China.
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Wang Q, Sha C, Wang H, Ma K, Wiegle J, Abomohra AEF, Shao W. A novel bifunctional aldehyde/alcohol dehydrogenase catalyzing reduction of acetyl-CoA to ethanol at temperatures up to 95 °C. Sci Rep 2021; 11:1050. [PMID: 33441766 PMCID: PMC7806712 DOI: 10.1038/s41598-020-80159-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 12/16/2020] [Indexed: 11/09/2022] Open
Abstract
Hyperthermophilic Thermotoga spp. are excellent candidates for the biosynthesis of cellulosic ethanol producing strains because they can grow optimally at 80 °C with ability to degrade and utilize cellulosic biomass. In T. neapolitana (Tne), a putative iron-containing alcohol dehydrogenase was, for the first time, revealed to be a bifunctional aldehyde/alcohol dehydrogenase (Fe-AAdh) that catalyzed both reactions from acetyl-coenzyme A (ac-CoA) to acetaldehyde (ac-ald), and from ac-ald to ethanol, while the putative aldehyde dehydrogenase (Aldh) exhibited only CoA-independent activity that oxidizes ac-ald to acetic acid. The biochemical properties of Fe-AAdh were characterized, and bioinformatics were analyzed. Fe-AAdh exhibited the highest activities for the reductions of ac-CoA and acetaldehyde at 80-85 °C, pH 7.54, and had a 1-h half-life at about 92 °C. The Fe-AAdh gene is highly conserved in Thermotoga spp., Pyrococcus furiosus and Thermococcus kodakarensis, indicating the existence of a fermentation pathway from ac-CoA to ethanol via acetaldehyde as the intermediate in hyperthermophiles.
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Affiliation(s)
- Qiang Wang
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Chong Sha
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Hongcheng Wang
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Kesen Ma
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Juergen Wiegle
- Department of Microbiology, University of Georgia, Athens, GA, 30602, USA
| | - Abd El-Fatah Abomohra
- Department of Environmental Engineering, School of Architecture and Civil Engineering, Chengdu University, Chengdu, 610106, China. .,Botany Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt.
| | - Weilan Shao
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China.
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Influence of Culture Conditions on the Bioreduction of Organic Acids to Alcohols by Thermoanaerobacter pseudoethanolicus. Microorganisms 2021; 9:microorganisms9010162. [PMID: 33445711 PMCID: PMC7828175 DOI: 10.3390/microorganisms9010162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/24/2020] [Accepted: 01/08/2021] [Indexed: 11/17/2022] Open
Abstract
Thermoanaerobacter species have recently been observed to reduce carboxylic acids to their corresponding alcohols. The present investigation shows that Thermoanaerobacter pseudoethanolicus converts C2-C6 short-chain fatty acids (SCFAs) to their corresponding alcohols in the presence of glucose. The conversion yields varied from 21% of 3-methyl-1-butyrate to 57.9% of 1-pentanoate being converted to their corresponding alcohols. Slightly acidic culture conditions (pH 6.5) was optimal for the reduction. By increasing the initial glucose concentration, an increase in the conversion of SCFAs reduced to their corresponding alcohols was observed. Inhibitory experiments on C2-C8 alcohols showed that C4 and higher alcohols are inhibitory to T. pseudoethanolicus suggesting that other culture modes may be necessary to improve the amount of fatty acids reduced to the analogous alcohol. The reduction of SCFAs to their corresponding alcohols was further demonstrated using 13C-labelled fatty acids and the conversion was followed kinetically. Finally, increased activity of alcohol dehydrogenase (ADH) and aldehyde oxidation activity was observed in cultures of T. pseudoethanolicus grown on glucose as compared to glucose supplemented with either 3-methyl-1-butyrate or pentanoate, using both NADH and NADPH as cofactors, although the presence of the latter showed higher ADH and aldehyde oxidoreductase (ALDH) activity.
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Genome Editing of the Anaerobic Thermophile Thermoanaerobacter ethanolicus Using Thermostable Cas9. Appl Environ Microbiol 2020; 87:AEM.01773-20. [PMID: 33067194 DOI: 10.1128/aem.01773-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/04/2020] [Indexed: 12/11/2022] Open
Abstract
Thermoanaerobacter ethanolicus can produce acetate, lactate, hydrogen, and ethanol from sugars resulting from plant carbohydrate polymer degradation at temperatures above 65°C. T. ethanolicus is a promising candidate for thermophilic ethanol fermentations due to the utilization of both pentose and hexose. Although an ethanol balance model in T. ethanolicus has been developed, only a few physiological or biochemical experiments regarding the function of important enzymes in ethanol formation have been carried out. To address this issue, we developed a thermostable Cas9-based system for genome editing of T. ethanolicus As a proof of principle, three genes, including the thymidine kinase gene (tdk), acetaldehyde-alcohol dehydrogenase gene (adhE), and redox sensing protein gene (rsp), were chosen as editing targets, and these genes were edited successfully. As a genetic tool, we tested the gene knockout and a small DNA fragment knock-in. After optimization of the transformation strategies, 77% genome-editing efficiency was observed. Furthermore, our in vivo results revealed that redox sensing protein (RSP) plays a more important role in regulation of energy metabolism, including hydrogen production and ethanol formation. The genetic system provides us with an effective strategy to identify genes involved in biosynthesis and energy metabolism.IMPORTANCE Interest in thermophilic microorganisms as emerging metabolic engineering platforms to produce biofuels and chemicals has surged. Thermophilic microbes for biofuels have attracted great attention, due to their tolerance of high temperature and wide range of substrate utilization. On the basis of the biochemical experiments of previous investigation, the formation of ethanol was controlled via transcriptional regulation and influenced by the relevant properties of specific enzymes in T. ethanolicus Thus, there is an urgent need to understand the physiological function of these key enzymes, which requires genetic manipulations such as deletion or overexpression of genes encoding putative key enzymes. Here, we developed a thermostable Cas9-based engineering tool for gene editing in T. ethanolicus The thermostable Cas9-based genome-editing tool may further be applied to metabolically engineer T. ethanolicus to produce biofuels. This genetic system represents an important expansion of the genetic tool box of anaerobic thermophile T. ethanolicus strains.
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Styles MQ, Nesbitt EA, Hoffmann TD, Queen J, Ortenzi MV, Leak DJ. The heterologous production of terpenes by the thermophile Parageobacillus thermoglucosidasius in a consolidated bioprocess using waste bread. Metab Eng 2020; 65:146-155. [PMID: 33189879 DOI: 10.1016/j.ymben.2020.11.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 08/26/2020] [Accepted: 11/08/2020] [Indexed: 11/16/2022]
Abstract
Parageobacillus thermoglucosidasius is a genetically tractable thermophile that grows rapidly at elevated temperatures, with a doubling time at 65 °C comparable to the shortest doubling times of Escherichia coli. It is capable of using a wide variety of substrates, including carbohydrate oligomers, and has been developed for the industrial production of ethanol. In this study, P. thermoglucosidasius NCIMB11955 has been engineered to produce the sesquiterpene τ-muurolol by introduction of a heterologous mevalonate pathway constructed using genes from several thermophilic archaea together with a recently characterised thermostable τ-muurolol synthase. P. thermoglucosidasius naturally uses the methylerythritol phosphate pathway for production of the terpene precursor, isopentenyl pyrophosphate, while archaea use a version of the mevalonate pathway. By introducing the orthogonal archaeal pathway it was possible to increase the flux through to sesquiterpene biosynthesis. Construction of such a large metabolic pathway created problems with genetic vector introduction and stability, so recombinant plasmids were introduced by conjugation, and a thermostable serine integrase system was developed for integration of large pathways onto the chromosome. Finally, by making the heterologous pathway maltose-inducible we demonstrate that the new strain is capable of using waste bread directly as an autoinduction carbon source for the production of terpenes in a consolidated bioprocess.
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Affiliation(s)
- Matthew Q Styles
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Edward A Nesbitt
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Timothy D Hoffmann
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Junichi Queen
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Maria V Ortenzi
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - David J Leak
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
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Scully SM, Orlygsson J. Biotransformation of Carboxylic Acids to Alcohols: Characterization of Thermoanaerobacter Strain AK152 and 1-Propanol Production via Propionate Reduction. Microorganisms 2020; 8:microorganisms8060945. [PMID: 32586016 PMCID: PMC7356315 DOI: 10.3390/microorganisms8060945] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 11/22/2022] Open
Abstract
Thermoanaerobacter strains have recently gained interest because of their ability to convert short chain fatty acids to alcohols using actively growing cells. Thermoanaerobacter thermohydrosulfuricus strain AK152 was physiologically investigated for its ethanol and other alcohol formation. The temperature and pH optimum of the strain was 70 °C and pH 7.0 and the strain degraded a variety of compounds present in lignocellulosic biomass like monosaccharides, disaccharides, and starch. The strain is highly ethanologenic, producing up to 86% of the theoretical ethanol yield form hexoses. Strain AK152 was inhibited by relatively low initial substrate (30 mM) concentration, leading to inefficient degradation of glucose and levelling up of all end-product formation. The present study shows that the strain produces alcohols from most of the tested carboxylic acids, with the highest yields for propionate conversion to propanol (40.7%) with kinetic studies demonstrating that the maximum conversion happens within the first 48 h of fermentation. Various physiological tests were performed to maximize the acid conversion to the alcohol which reveals that the optimum pH for propionate conversion is pH 6.7 which affords a 57.3% conversion. Kinetic studies reveal that propionate conversion is rapid, achieving a maximum conversion within the first 48 h of fermentation. Finally, by using 13C NMR, it was shown that the addition of propionate indeed converted to propanol.
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Consolidated bio-saccharification: Leading lignocellulose bioconversion into the real world. Biotechnol Adv 2020; 40:107535. [DOI: 10.1016/j.biotechadv.2020.107535] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 02/03/2020] [Accepted: 02/12/2020] [Indexed: 11/22/2022]
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40
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Qu C, Chen L, Li Y, Fu H, Wang J. The redox-sensing transcriptional repressor Rex is important for regulating the products distribution in Thermoanaerobacterium aotearoense SCUT27. Appl Microbiol Biotechnol 2020; 104:5605-5617. [DOI: 10.1007/s00253-020-10554-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 02/28/2020] [Accepted: 03/16/2020] [Indexed: 01/06/2023]
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41
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Yang Z, Sun Q, Tan G, Zhang Q, Wang Z, Li C, Qi F, Wang W, Zhang L, Li Z. Engineering thermophilic Geobacillus thermoglucosidasius for riboflavin production. Microb Biotechnol 2020; 14:363-373. [PMID: 32096925 PMCID: PMC7936320 DOI: 10.1111/1751-7915.13543] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 01/17/2020] [Accepted: 01/24/2020] [Indexed: 01/17/2023] Open
Abstract
The potential advantages for fermentation production of chemicals at high temperatures are attractive, such as promoting the rate of biochemical reactions, reducing the risk of contamination and the energy consumption for fermenter cooling. In this work, we de novo engineered the thermophile Geobacillus thermoglucosidasius to produce riboflavin, since this bacterium can ferment diverse carbohydrates at an optimal temperature of 60°C with a high growth rate. We first introduced a heterogeneous riboflavin biosynthetic gene cluster and enabled the strain to produce detectable riboflavin (28.7 mg l−1). Then, with the aid of an improved gene replacement method, we preformed metabolic engineering in this strain, including replacement of ribCGtg with a mutant allele to weaken the consumption of riboflavin, manipulation of purine pathway to enhance precursor supply, deletion of ccpNGtg to tune central carbon catabolism towards riboflavin production and elimination of the lactate dehydrogenase gene to block the dominating product lactic acid. Finally, the engineered strain could produce riboflavin with the titre of 1034.5 mg l−1 after 12‐h fermentation in a mineral salt medium, indicating G. thermoglucosidasius is a promising host to develop high‐temperature cell factory of riboflavin production. This is the first demonstration of riboflavin production in thermophilic bacteria at an elevated temperature.
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Affiliation(s)
- Zhiheng Yang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Xuhui District, Shanghai, 200237, China
| | - Qingqing Sun
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Chaoyang District, Beijing, 100101, China
| | - Gaoyi Tan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Xuhui District, Shanghai, 200237, China
| | - Quanwei Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Chaoyang District, Beijing, 100101, China
| | - Zhengduo Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Xuhui District, Shanghai, 200237, China
| | - Chuan Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Xuhui District, Shanghai, 200237, China
| | - Fengxian Qi
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Chaoyang District, Beijing, 100101, China
| | - Weishan Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Xuhui District, Shanghai, 200237, China.,State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Chaoyang District, Beijing, 100101, China
| | - Lixin Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Xuhui District, Shanghai, 200237, China
| | - Zilong Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Chaoyang District, Beijing, 100101, China
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Zymomonas mobilis metabolism: Novel tools and targets for its rational engineering. Adv Microb Physiol 2020; 77:37-88. [PMID: 34756211 DOI: 10.1016/bs.ampbs.2020.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Zymomonas mobilis is an α-proteobacterium that interests the biofuel industry due to its perfect ethanol fermentation yields. From its first description as a bacterial isolate in fermented alcoholic beverages to date, Z. mobilis has been rigorously studied in directions basic and applied. The Z. mobilis powerful Entner-Doudoroff glycolytic pathway has been the center of rigorous biochemical studies and, aside from ethanol, it has attracted interest in terms of high-added-value chemical manufacturing. Energetic balances and the effects of respiration have been explored in fundamental directions as also in applications pursuing strain enhancement and the utilization of alternative carbon sources. Metabolic modeling has addressed the optimization of the biochemical circuitry at various conditions of growth and/or substrate utilization; it has been also critical in predicting desirable end-product yields via flux redirection. Lastly, stress tolerance has received particular attention, since it directly determines biocatalytical performance at challenging bioreactor conditions. At a genetic level, advances in the genetic engineering of the organism have brought forth beneficial manipulations in the Z. mobilis gene pool, e.g., knock-outs, knock-ins and gene stacking, aiming to broaden the metabolic repertoire and increase robustness. Recent omic and expressional studies shed light on the genomic content of the most applied strains and reveal landscapes of activity manifested at ambient or reactor-based conditions. Studies such as those reviewed in this work, contribute to the understanding of the biology of Z. mobilis, enable insightful strain development, and pave the way for the transformation of Z. mobilis into a consummate organism for biomass conversion.
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Fan L, Li M, Li Y, Fan X, Liu Y, Lv Y. Draft Genome Sequence of Thermophilic Bacillus sp. TYF-LIM-B05 Directly Producing Ethanol from Various Carbon Sources Including Lignocellulose. Curr Microbiol 2019; 77:491-499. [PMID: 31832840 DOI: 10.1007/s00284-019-01833-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/29/2019] [Indexed: 12/01/2022]
Abstract
Bacillus sp. TYF-LIM-B05, which is isolated from spoilage vinegar, is resistant to high temperature, high concentrated alcohol, acid, and salt, and can produce ethanol from mono-, di-, polysaccharide, and complex biomass as the sole carbon source. Thus, this strain is a potential candidate for consolidated bioprocessing (CBP) of fermenting lignocellulose to ethanol in a single step. To provide insight into the key enzymes involved in lignocellulose degradation and ethanol production, a draft genome of TYF-LIM-B05 was developed in this study. The results indicated that 348 genes are related to carbohydrate transport and metabolism according to the clusters of orthologous groups of proteins and annotated 187 CAZy domains from a total of 61 different families. The presence of genes encoding laccases, quinone oxidoreductases/reductases, and aryl-alcohol dehydrogenases further implies that TYF-LIM-B05 has the potential to degrade lignin. Remarkably, this strain has the ability to catalyze the oxidative decarboxylation of pyruvate to acetyl-CoA by pyruvate dehydrogenase complexes. The genomic information provided in this study will help researchers to better understand the mechanisms of the lignocellulose degradation and ethanol production pathway in thermophiles.
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Affiliation(s)
- Lulu Fan
- College of Environmental Science and Engineering, Taiyuan University of Technology, No. 209 of University Street, Yuci District, Jinzhong, 030600, Shanxi, China
| | - Min Li
- College of Biomedical Engineering, Taiyuan University of Technology, No. 209 of University Street, Yuci District, Jinzhong, 030600, Shanxi, China
| | - Yao Li
- College of Biomedical Engineering, Taiyuan University of Technology, No. 209 of University Street, Yuci District, Jinzhong, 030600, Shanxi, China
| | - Xiaojun Fan
- College of Environmental Science and Engineering, Taiyuan University of Technology, No. 209 of University Street, Yuci District, Jinzhong, 030600, Shanxi, China. .,Innovation Institute of Environmental Industry, Taiyuan University of Technology, No. 209 of University Street, Yuci District, Jinzhong, 030600, Shanxi, China.
| | - Yuxiang Liu
- College of Environmental Science and Engineering, Taiyuan University of Technology, No. 209 of University Street, Yuci District, Jinzhong, 030600, Shanxi, China.
| | - Yongkang Lv
- Key Laboratory of Coal Science and Technology, Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan, 030024, Shanxi, China
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44
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Sutiono S, Satzinger K, Pick A, Carsten J, Sieber V. To beat the heat - engineering of the most thermostable pyruvate decarboxylase to date. RSC Adv 2019; 9:29743-29746. [PMID: 35531508 PMCID: PMC9071941 DOI: 10.1039/c9ra06251c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Accepted: 09/03/2019] [Indexed: 12/23/2022] Open
Abstract
Pyruvate decarboxylase (PDC) is a key enzyme for the production of ethanol at high temperatures and for cell-free butanol synthesis. Thermostable, organic solvent stable PDC was evolved from bacterial PDCs. The new variant shows >1500-fold-improved half-life at 75 °C and >5000-fold-increased half-life in the presence of 9 vol% butanol at 50 °C.
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Affiliation(s)
- Samuel Sutiono
- Chair of Chemistry of Biogenic Resources, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich Schulgasse 16 94315 Straubing Germany
| | - Katharina Satzinger
- Chair of Chemistry of Biogenic Resources, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich Schulgasse 16 94315 Straubing Germany
| | - André Pick
- Chair of Chemistry of Biogenic Resources, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich Schulgasse 16 94315 Straubing Germany
| | - Jörg Carsten
- Chair of Chemistry of Biogenic Resources, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich Schulgasse 16 94315 Straubing Germany
- Catalytic Research Center, Technical University of Munich Ernst-Otto-Fischer-Straße 1 85748 Garching Germany
| | - Volker Sieber
- Chair of Chemistry of Biogenic Resources, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich Schulgasse 16 94315 Straubing Germany
- Catalytic Research Center, Technical University of Munich Ernst-Otto-Fischer-Straße 1 85748 Garching Germany
- Straubing Branch BioCat Fraunhofer IGB Schulgasse 11a 94315 Straubing Germany
- School of Chemistry and Molecular Biosciences, The University of Queensland 68 Copper Road St. Lucia 4072 Australia
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45
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Ethanol yield and sugar usability in thermophilic ethanol production from lignocellulose hydrolysate by genetically engineered Moorella thermoacetica. J Biosci Bioeng 2019; 129:160-164. [PMID: 31506242 DOI: 10.1016/j.jbiosc.2019.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 07/29/2019] [Accepted: 08/16/2019] [Indexed: 02/07/2023]
Abstract
Bioconversion from inexpensive renewable resource, such as biomass, to liquid fuel is one of the promising technologies to reduce the use of petroleum. We previously reported the genetically engineered Moorella thermoacetica could produce ethanol from the lignocellulosic feedstock. However, it was still unclear which carbon source in the substrate was preferentially consumed to produce ethanol. To identify the hierarchy of the sugar utilization during ethanol fermentation of this strain, we analyzed the sugar composition of lignocellulosic feedstock, and consumption rate of sugars during the fermentation process. The hydrolysates after acid pretreatment and enzymatic saccharification contained glucose, xylose, galactose, arabinose, and mannose. Time course data suggested that xylose was the most preferred carbon source among those sugars during ethanol fermentation. Ethanol yield was 0.40 ± 0.06 and 0.40 ± 0.12 g/g-total sugar, from lignocellulosic hydrolysates of Japanese cedar (Cryptomeria japonica) and rice straw (Oryza sativa), respectively. The results demonstrated that the genetically engineered M. thermoacetica is a promising candidate for thermophilic ethanol fermentation of lignocellulosic feedstocks, especially hemicellulosic sugars.
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Bashir Z, Sheng L, Anil A, Lali A, Minton NP, Zhang Y. Engineering Geobacillus thermoglucosidasius for direct utilisation of holocellulose from wheat straw. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:199. [PMID: 31452680 PMCID: PMC6701081 DOI: 10.1186/s13068-019-1540-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 08/06/2019] [Indexed: 05/29/2023]
Abstract
BACKGROUND A consolidated bioprocessing (CBP), where lignocellulose is converted into the desired product(s) in a single fermentative step without the addition of expensive degradative enzymes, represents the ideal solution of renewable routes to chemicals and fuels. Members of the genus Geobacillus are able to grow at elevated temperatures and are able to utilise a wide range of oligosaccharides derived from lignocellulose. This makes them ideally suited to the development of CBP. RESULTS In this study, we engineered Geobacillus thermoglucosidasius NCIMB 11955 to utilise lignocellulosic biomass, in the form of nitric acid/ammonia treated wheat straw to which expensive hydrolytic enzymes had not been added. Two different strains, BZ9 and BZ10, were generated by integrating the cglT (β-1,4-glucosidase) gene from Thermoanaerobacter brockii into the genome, and localising genes encoding different cellulolytic enzymes on autonomous plasmids. The plasmid of strain BZ10 carried a synthetic cellulosomal operon comprising the celA (Endoglucanase A) gene from Clostridium thermocellum and cel6B (Exoglucanase) from Thermobifida fusca; whereas, strain BZ9 contained a plasmid encoding the celA (multidomain cellulase) gene from Caldicellulosiruptor bescii. All of the genes were successfully expressed, and their encoded products secreted in a functionally active form, as evidenced by their detection in culture supernatants by Western blotting and enzymatic assay. In the case of the C. bescii CelA enzyme, this is one of the first times that the heterologous production of this multi-functional enzyme has been achieved in a heterologous host. Both strains (BZ9 and BZ10) exhibited improved growth on pre-treated wheat straw, achieving a higher final OD600 and producing greater numbers of viable cells. To demonstrate that cellulosic ethanol can be produced directly from lignocellulosic biomass by a single organism, we established our consortium of hydrolytic enzymes in a previously engineered ethanologenic G. thermoglucosidasius strain, LS242. We observed approximately twofold and 1.6-fold increase in ethanol production in the recombinant G. thermoglucosidasius equivalent to BZ9 and BZ10, respectively, compared to G. thermoglucosidasius LS242 strain at 24 h of growth. CONCLUSION We engineered G. thermoglucosidasius to utilise a real-world lignocellulosic biomass substrate and demonstrated that cellulosic ethanol can be produced directly from lignocellulosic biomass in one step. Direct conversion of biomass into desired products represents a new paradigm for CBP, offering the potential for carbon neutral, cost-effective production of sustainable chemicals and fuels.
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Affiliation(s)
- Zeenat Bashir
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Lili Sheng
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Annamma Anil
- DBT-ICT Centre for Energy Biosciences, Institute of Chemical Technology, Nathalal Parikh Marg, Mumbai, 400019 India
| | - Arvind Lali
- DBT-ICT Centre for Energy Biosciences, Institute of Chemical Technology, Nathalal Parikh Marg, Mumbai, 400019 India
| | - Nigel P. Minton
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Ying Zhang
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
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Wade Y, Daniel RA, Leak DJ. Heterologous Microcompartment Assembly in Bacillaceae: Establishing the Components Necessary for Scaffold Formation. ACS Synth Biol 2019; 8:1642-1654. [PMID: 31242391 DOI: 10.1021/acssynbio.9b00155] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Bacterial microcompartments (BMCs) are organelles that host specific biochemical reactions for both anabolic and catabolic functions. Engineered morphologically diverse BMCs bearing heterologous enzymatic pathways have shown enhanced productivity for commodity chemicals, which makes BMCs an important focus for metabolic engineering. Gaining control of BMC assembly and incorporation of a heterologous enzymatic cargo has yet to be achieved in thermophiles. Herein, we address this by first conducting a detailed bioinformatic analysis of the propanediol utilization (pdu) operon in the thermophile Parageobacillus thermoglucosidasius. We then demonstrated, in vivo, the ability to assemble the native BMCs at an elevated temperature of 60 °C. Heterologous expression of Pdu shell proteins from P. thermoglucosidasius in Bacillus subtilis resulted in the assembly of a single tubular BMC with an average length of 1.4 μm; BMCs assembled after a 20 min induction of expression of the shell operons. Moreover, we show that it is possible to target the monomeric superfolder GFP (msfGFP) to the interior of the compartment by fusion of an N-terminal sequence of the propanediol utilization protein (PduP) of at least 24 amino acids. This study establishes the feasibility of constructing cell factories for small molecules in industrially important Bacillus and Geobacillus spp. by heterologous cargo-carrying BMC production and assembly. Additionally, the study provides experimental confirmation that BMCs are produced in thermophilic bacteria, which opens a path for future research on repurposing the native organelles to provide new functionality at elevated temperatures.
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Affiliation(s)
- Yana Wade
- Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle-upon-Tyne, NE2 4AX, U.K
| | - Richard A. Daniel
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle-upon-Tyne, NE2 4AX, U.K
| | - David J. Leak
- Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
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Luo T, Huang H, Mei Z, Shen F, Ge Y, Hu G, Meng X. Hydrothermal pretreatment of rice straw at relatively lower temperature to improve biogas production via anaerobic digestion. CHINESE CHEM LETT 2019. [DOI: 10.1016/j.cclet.2019.03.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Patel AK, Singhania RR, Sim SJ, Pandey A. Thermostable cellulases: Current status and perspectives. BIORESOURCE TECHNOLOGY 2019; 279:385-392. [PMID: 30685132 DOI: 10.1016/j.biortech.2019.01.049] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/09/2019] [Accepted: 01/11/2019] [Indexed: 05/18/2023]
Abstract
It is envisaged that the utilization of lignocellulosic biomass for ethanol production for transport sector, would make cellulases the most demanded industrial enzyme. The greatest potential of cellulolytic enzymes lies in ethanol production from biomass by enzymatic hydrolysis of cellulose but low thermostability and low titer of cellulase production resulting into high cost of the enzyme which is the major set-back. A number of research groups are working on cellulase to improve its thermostability so as to be able to perform hydrolysis at elevated temperatures which would eventually increase the efficiency of cellulose hydrolysis. The technologies developed from lignocellulosic biomass via cellulose hydrolysis promise environmental and economical sustainability in the long run along with non-dependence on nonrenewable energy source. This review deals with the important sources of thermostable cellulases, mechanism, its regulation, strategies to enhance the thermostability further with respect to its importance for biofuel applications.
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Affiliation(s)
- Anil K Patel
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Republic of Korea
| | | | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Ashok Pandey
- Centre for Innovation and Translational Research, Indian Institute of Toxicological Research, Lucknow 226 001, India
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Scully SM, Brown A, Ross AB, Orlygsson J. Biotransformation of organic acids to their corresponding alcohols by Thermoanaerobacter pseudoethanolicus. Anaerobe 2019; 57:28-31. [PMID: 30876932 DOI: 10.1016/j.anaerobe.2019.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/15/2019] [Accepted: 03/05/2019] [Indexed: 11/24/2022]
Abstract
Higher order alcohols, such as 1-butanol and 1-hexanol, have a large number of applications but are currently prepared from non-renewable feedstocks. Here, the ability of Thermoanaerobacter pseudoethanolicus to reduce short-chain fatty acids to their corresponding alcohols using reducing potential generated by glucose catabolism with yields between 21.0 and 61.0%. 13C-labelled acetate, 1-propionate and 1-butyrate demonstrates that exogenously added fatty acids are indeed reduced to their corresponding alcohols. This mode of producing primary alcohols from fatty acids using a thermophilic anaerobe opens the door for the production of such alcohols from low-value materials using an inexpensive source of reducing potential.
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Affiliation(s)
- Sean M Scully
- Faculty of Natural Resource Science, University of Akureyri, Borgir, Nordurslod 2, 600, Akureyri, Iceland
| | - Aaron Brown
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Andrew B Ross
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Johann Orlygsson
- Faculty of Natural Resource Science, University of Akureyri, Borgir, Nordurslod 2, 600, Akureyri, Iceland.
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