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Rudra Gouda M, Kumaranag K, Ramakrishnan B, Subramanian S. Deciphering the complex interplay between gut microbiota and crop residue breakdown in forager and hive bees ( Apis mellifera L.). CURRENT RESEARCH IN MICROBIAL SCIENCES 2024; 6:100233. [PMID: 38572354 PMCID: PMC10990707 DOI: 10.1016/j.crmicr.2024.100233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024] Open
Abstract
This study investigates A. mellifera gut microbiota diversity and enzymatic activities, aiming to utilize identified isolates for practical applications in sustainable crop residue management and soil health enhancement. This study sampled honey bees, analyzed gut bacterial diversity via 16S rRNA gene, and screened isolates for cellulolytic, hemicellulolytic, and pectinolytic activities, with subsequent assessment of enzymatic potential. The study reveals that cellulolytic and hemicellulolytic bacterial isolates, mainly from γ-Proteobacteria, Actinobacteria, and Firmicutes, have significant potential for crop residue management. Some genera, like Aneurinibacillus, Bacillus, Clostridium, Enterobacter, Serratia, Stenotrophomonas, Apilactobacillus, Lysinibacillus, and Pseudomonas, are very good at breaking down cellulose and hemicellulase. Notable cellulose-degrading genera include Cedecea (1.390 ± 0.57), Clostridium (1.360 ± 0.86 U/mg), Enterobacter (1.493 ± 1.10 U/mg), Klebsiella (1.380 ± 2.03 U/mg), and Serratia (1.402 ± 0.31 U/mg), while Aneurinibacillus (1.213 ± 1.12 U/mg), Bacillus (3.119 ± 0.55 U/mg), Enterobacter (1.042 ± 0.14 U/mg), Serratia (1.589 ± 0.05 U/mg), and Xanthomonas (1.156 ± 0.08 U/mg) excel in hemicellulase activity. Specific isolates with high cellulolytic and hemicellulolytic activities are identified, highlighting their potential for crop residue management. The research explores gut bacterial compartmentalization in A. mellifera, emphasising gut physiology's role in cellulose and hemicellulose digestion. Pectinolytic activity is observed, particularly in the Bacillaceae clade (3.229 ± 0.02), contributing to understanding the honey bee gut microbiome. The findings offer insights into microbiome diversity and enzymatic capabilities, with implications for biotechnological applications in sustainable crop residue management. The study concludes by emphasizing the need for ongoing research to uncover underlying mechanisms and ecological factors influencing gut microbiota, impacting honey bee health, colony dynamics, and advancements in crop residue management.
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Affiliation(s)
- M.N. Rudra Gouda
- Division of Entomology, Indian Agricultural Research Institute, New Delhi, 110012, India
| | - K.M. Kumaranag
- Division of Entomology, Indian Agricultural Research Institute, New Delhi, 110012, India
| | - B. Ramakrishnan
- Division of Microbiology, Indian Agricultural Research Institute, New Delhi, 110012, India
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Zajki-Zechmeister K, Eibinger M, Kaira GS, Nidetzky B. Mechanochemical Coupling of Catalysis and Motion in a Cellulose-Degrading Multienzyme Nanomachine. ACS Catal 2024; 14:2656-2663. [PMID: 38384941 PMCID: PMC10877591 DOI: 10.1021/acscatal.3c05653] [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: 11/21/2023] [Revised: 01/13/2024] [Accepted: 01/24/2024] [Indexed: 02/23/2024]
Abstract
The cellulosome is a megadalton-size protein complex that functions as a biological nanomachine of cellulosic fiber degradation. We show that the cellulosome behaves as a Brownian ratchet that rectifies protein motions on the cellulose surface into a propulsion mechanism by coupling to the hydrolysis of cellulose chains. Movement on cellulose fibrils is unidirectional and results from "macromolecular crawl" composed of dynamic switches between elongated and compact spatial arrangements of enzyme subunits. Deletion of the main exocellulase Cel48S eliminates conformational bias for aligning the subunits to the long fibril axis, which we reveal as crucial for optimum coupling between directional movement and substrate degradation. Implications of the cellulosome acting as a mechanochemical motor suggest a distinct mechanism of enzymatic machinery in the deconstruction of cellulose assemblies.
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Affiliation(s)
- Krisztina Zajki-Zechmeister
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, Graz 8010, Austria
| | - Manuel Eibinger
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, Graz 8010, Austria
| | - Gaurav Singh Kaira
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, Graz 8010, Austria
- Austrian
Centre of Industrial Biotechnology, Petersgasse 14, Graz 8010, Austria
| | - Bernd Nidetzky
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, Graz 8010, Austria
- Austrian
Centre of Industrial Biotechnology, Petersgasse 14, Graz 8010, Austria
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Asemoloye MD, Bello TS, Oladoye PO, Remilekun Gbadamosi M, Babarinde SO, Ebenezer Adebami G, Olowe OM, Temporiti MEE, Wanek W, Marchisio MA. Engineered yeasts and lignocellulosic biomaterials: shaping a new dimension for biorefinery and global bioeconomy. Bioengineered 2023; 14:2269328. [PMID: 37850721 PMCID: PMC10586088 DOI: 10.1080/21655979.2023.2269328] [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: 06/24/2023] [Accepted: 10/03/2023] [Indexed: 10/19/2023] Open
Abstract
The next milestone of synthetic biology research relies on the development of customized microbes for specific industrial purposes. Metabolic pathways of an organism, for example, depict its chemical repertoire and its genetic makeup. If genes controlling such pathways can be identified, scientists can decide to enhance or rewrite them for different purposes depending on the organism and the desired metabolites. The lignocellulosic biorefinery has achieved good progress over the past few years with potential impact on global bioeconomy. This principle aims to produce different bio-based products like biochemical(s) or biofuel(s) from plant biomass under microbial actions. Meanwhile, yeasts have proven very useful for different biotechnological applications. Hence, their potentials in genetic/metabolic engineering can be fully explored for lignocellulosic biorefineries. For instance, the secretion of enzymes above the natural limit (aided by genetic engineering) would speed-up the down-line processes in lignocellulosic biorefineries and the cost. Thus, the next milestone would greatly require the development of synthetic yeasts with much more efficient metabolic capacities to achieve basic requirements for particular biorefinery. This review gave comprehensive overview of lignocellulosic biomaterials and their importance in bioeconomy. Many researchers have demonstrated the engineering of several ligninolytic enzymes in heterologous yeast hosts. However, there are still many factors needing to be well understood like the secretion time, titter value, thermal stability, pH tolerance, and reactivity of the recombinant enzymes. Here, we give a detailed account of the potentials of engineered yeasts being discussed, as well as the constraints associated with their development and applications.
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Affiliation(s)
- Michael Dare Asemoloye
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, Nankai District, China
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Tunde Sheriffdeen Bello
- Department of Plant Biology, School of Life Sciences, Federal University of Technology Minna, Minna Niger State, Nigeria
| | | | | | - Segun Oladiran Babarinde
- Department of Plant, Food and Environmental Sciences, Faculty of Agriculture, Dalhousie University, Truro, Nova Scotia, Canada
| | | | - Olumayowa Mary Olowe
- Food Security and Safety Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Mail Bag, Mmabatho, South Africa
| | | | - Wolfgang Wanek
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Mario Andrea Marchisio
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, Nankai District, China
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Iglesias Rando MR, Gorojovsky N, Zylberman V, Goldbaum FA, Craig PO. Improvement of Cellulomonas fimi endoglucanase CenA by multienzymatic display on a decameric structural scaffold. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12581-6. [PMID: 37212884 DOI: 10.1007/s00253-023-12581-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 04/27/2023] [Accepted: 05/06/2023] [Indexed: 05/23/2023]
Abstract
The development of multifunctional particles using polymeric scaffolds is an emerging technology for many nanobiotechnological applications. Here we present a system for the production of multifunctional complexes, based on the high affinity non-covalent interaction of cohesin and dockerin modules complementary fused to decameric Brucella abortus lumazine synthase (BLS) subunits, and selected target proteins, respectively. The cohesin-BLS scaffold was solubly expressed in high yield in Escherichia coli, and revealed a high thermostability. The production of multienzymatic particles using this system was evaluated using the catalytic domain of Cellulomonas fimi endoglucanase CenA recombinantly fused to a dockerin module. Coupling of the enzyme to the scaffold was highly efficient and occurred with the expected stoichiometry. The decavalent enzymatic complexes obtained showed higher cellulolytic activity and association to the substrate compared to equivalent amounts of the free enzyme. This phenomenon was dependent on the multiplicity and proximity of the enzymes coupled to the scaffold, and was attributed to an avidity effect in the polyvalent enzyme interaction with the substrate. Our results highlight the usefulness of the scaffold presented in this work for the development of multifunctional particles, and the improvement of lignocellulose degradation among other applications. KEY POINTS: • New system for multifunctional particle production using the BLS scaffold • Higher cellulolytic activity of polyvalent endoglucanase compared to the free enzyme • Amount of enzyme associated to cellulose is higher for the polyvalent endoglucanase.
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Affiliation(s)
- Matías R Iglesias Rando
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160 (CP 1428), Buenos Aires, Argentina
- CONICET-Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Intendente Güiraldes 2160 (CP 1428), Buenos Aires, Argentina
| | - Natalia Gorojovsky
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160 (CP 1428), Buenos Aires, Argentina
- CONICET-Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Intendente Güiraldes 2160 (CP 1428), Buenos Aires, Argentina
| | - Vanesa Zylberman
- Inmunova SA, Gral. San Martín, 25 de Mayo 1021 (CP 1650), Villa Lynch, Buenos Aires, Argentina
| | - Fernando A Goldbaum
- Inmunova SA, Gral. San Martín, 25 de Mayo 1021 (CP 1650), Villa Lynch, Buenos Aires, Argentina
- Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435 (CP 1405), Buenos Aires, Argentina
- Centro de Rediseño e Ingeniería de Proteínas (CRIP), UNSAM Campus Miguelete, 25 de Mayo y Francia (CP 1650), Gral. San Martín, Buenos Aires, Argentina
| | - Patricio O Craig
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160 (CP 1428), Buenos Aires, Argentina.
- CONICET-Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Intendente Güiraldes 2160 (CP 1428), Buenos Aires, Argentina.
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Lamote B, da Fonseca MJM, Vanderstraeten J, Meert K, Elias M, Briers Y. Current challenges in designer cellulosome engineering. Appl Microbiol Biotechnol 2023; 107:2755-2770. [PMID: 36941434 DOI: 10.1007/s00253-023-12474-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/28/2023] [Accepted: 03/03/2023] [Indexed: 03/23/2023]
Abstract
Designer cellulosomes (DCs) are engineered multi-enzyme complexes, comprising carbohydrate-active enzymes attached to a common backbone, the scaffoldin, via high-affinity cohesin-dockerin interactions. The use of DCs in the degradation of renewable biomass polymers is a promising approach for biorefineries. Indeed, DCs have shown significant hydrolytic activities due to the enhanced enzyme-substrate proximity and inter-enzyme synergies, but technical hurdles in DC engineering have hindered further progress towards industrial application. The challenge in DC engineering lies in the large diversity of possible building blocks and architectures, resulting in a multivariate and immense design space. Simultaneously, the precise DC composition affects many relevant parameters such as activity, stability, and manufacturability. Since protein engineers face a lack of high-throughput approaches to explore this vast design space, DC engineering may result in an unsatisfying outcome. This review provides a roadmap to guide researchers through the process of DC engineering. Each step, starting from concept to evaluation, is described and provided with its challenges, along with possible solutions, both for DCs that are assembled in vitro or are displayed on the yeast cell surface. KEY POINTS: • Construction of designer cellulosomes is a multi-step process. • Designer cellulosome research deals with multivariate construction challenges. • Boosting designer cellulosome efficiency requires exploring a vast design space.
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Affiliation(s)
- Babette Lamote
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Ghent, Belgium
- Centre for Synthetic Biology, Department of Biotechnology, Ghent University, Ghent, Belgium
| | | | - Julie Vanderstraeten
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Ghent, Belgium
| | - Kenan Meert
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Ghent, Belgium
- Laboratory of Applied Mycology and Phenomics, Department of Plants and Crops, Ghent University, Ghent, Belgium
| | - Marte Elias
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Ghent, Belgium
- Centre for Synthetic Biology, Department of Biotechnology, Ghent University, Ghent, Belgium
| | - Yves Briers
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Ghent, Belgium.
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Madhavan A, Arun KB, Sindhu R, Nair BG, Pandey A, Awasthi MK, Szakacs G, Binod P. Design and genome engineering of microbial cell factories for efficient conversion of lignocellulose to fuel. BIORESOURCE TECHNOLOGY 2023; 370:128555. [PMID: 36586428 DOI: 10.1016/j.biortech.2022.128555] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
The gradually increasing need for fossil fuels demands renewable biofuel substitutes. This has fascinated an increasing investigation to design innovative energy fuels that have comparable Physico-chemical and combustion characteristics with fossil-derived fuels. The efficient microbes for bioenergy synthesis desire the proficiency to consume a large quantity of carbon substrate, transfer various carbohydrates through efficient metabolic pathways, capability to withstand inhibitory components and other degradation compounds, and improve metabolic fluxes to synthesize target compounds. Metabolically engineered microbes could be an efficient methodology for synthesizing biofuel from cellulosic biomass by cautiously manipulating enzymes and metabolic pathways. This review offers a comprehensive perspective on the trends and advances in metabolic and genetic engineering technologies for advanced biofuel synthesis by applying various heterologous hosts. Probable technologies include enzyme engineering, heterologous expression of multiple genes, CRISPR-Cas technologies for genome editing, and cell surface display.
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Affiliation(s)
- Aravind Madhavan
- School of Biotechnology, Amrita Vishwa Vidyapeetham, Amritapuri, Kollam 690525 Kerala, India.
| | - K B Arun
- Department of Life Sciences, CHRIST (Deemed to be University), Bengaluru 560029, Karnataka, India
| | - Raveendran Sindhu
- Department of Food Technology, TKM Institute of Technology, Kollam 689 122, India
| | - Bipin G Nair
- School of Biotechnology, Amrita Vishwa Vidyapeetham, Amritapuri, Kollam 690525 Kerala, India
| | - Ashok Pandey
- Center for Innovation and Translational Research, CSIR-Indian Institute of Toxicology Research, Lucknow 226 001, India; Sustainability Cluster, School of Engineering, University of Petroleum and Energy Studies, Dehradun 248007, Uttarkhand, India; Centre for Energy and Environmental Sustainability, Lucknow 226 029, Uttar Pradesh, India
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi 712 100, China
| | - George Szakacs
- Budapest University of Technology and Economics, Department of Applied Biotechnology and Food Science, 1111 Budapest, Szent Gellert ter 4, Hungary
| | - Parameswaran Binod
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Trivandrum 695 019, India
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Moraïs S, Stern J, Artzi L, Fontes CMGA, Bayer EA, Mizrahi I. Carbohydrate Depolymerization by Intricate Cellulosomal Systems. Methods Mol Biol 2023; 2657:53-77. [PMID: 37149522 DOI: 10.1007/978-1-0716-3151-5_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Cellulosomes are multi-enzymatic nanomachines that have been fine-tuned through evolution to efficiently deconstruct plant biomass. Integration of cellulosomal components occurs via highly ordered protein-protein interactions between the various enzyme-borne dockerin modules and the multiple copies of the cohesin modules located on the scaffoldin subunit. Recently, designer cellulosome technology was established to provide insights into the architectural role of catalytic (enzymatic) and structural (scaffoldin) cellulosomal constituents for the efficient degradation of plant cell wall polysaccharides. Owing to advances in genomics and proteomics, highly structured cellulosome complexes have recently been unraveled, and the information gained has inspired the development of designer-cellulosome technology to new levels of complex organization. These higher-order designer cellulosomes have in turn fostered our capacity to enhance the catalytic potential of artificial cellulolytic complexes. In this chapter, methods to produce and employ such intricate cellulosomal complexes are reported.
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Affiliation(s)
- Sarah Moraïs
- Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Johanna Stern
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Lior Artzi
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | | | - Edward A Bayer
- Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel.
| | - Itzhak Mizrahi
- Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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Dorival J, Moraïs S, Labourel A, Rozycki B, Cazade PA, Dabin J, Setter-Lamed E, Mizrahi I, Thompson D, Thureau A, Bayer EA, Czjzek M. Mapping the deformability of natural and designed cellulosomes in solution. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:68. [PMID: 35725490 PMCID: PMC9210761 DOI: 10.1186/s13068-022-02165-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 06/08/2022] [Indexed: 12/02/2022]
Abstract
Background Natural cellulosome multi-enzyme complexes, their components, and engineered ‘designer cellulosomes’ (DCs) promise an efficient means of breaking down cellulosic substrates into valuable biofuel products. Their broad uptake in biotechnology relies on boosting proximity-based synergy among the resident enzymes, but the modular architecture challenges structure determination and rational design. Results We used small angle X-ray scattering combined with molecular modeling to study the solution structure of cellulosomal components. These include three dockerin-bearing cellulases with distinct substrate specificities, original scaffoldins from the human gut bacterium Ruminococcus champanellensis (ScaA, ScaH and ScaK) and a trivalent cohesin-bearing designer scaffoldin (Scaf20L), followed by cellulosomal complexes comprising these components, and the nonavalent fully loaded Clostridium thermocellum CipA in complex with Cel8A from the same bacterium. The size analysis of Rg and Dmax values deduced from the scattering curves and corresponding molecular models highlight their variable aspects, depending on composition, size and spatial organization of the objects in solution. Conclusions Our data quantifies variability of form and compactness of cellulosomal components in solution and confirms that this native plasticity may well be related to speciation with respect to the substrate that is targeted. By showing that scaffoldins or components display enhanced compactness compared to the free objects, we provide new routes to rationally enhance their stability and performance in their environment of action. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02165-3.
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Vanderstraeten J, da Fonseca MJM, De Groote P, Grimon D, Gerstmans H, Kahn A, Moraïs S, Bayer EA, Briers Y. Combinatorial assembly and optimisation of designer cellulosomes: a galactomannan case study. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:60. [PMID: 35637485 PMCID: PMC9153192 DOI: 10.1186/s13068-022-02158-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 05/14/2022] [Indexed: 11/10/2022]
Abstract
BACKGROUND Designer cellulosomes are self-assembled chimeric enzyme complexes that can be used to improve lignocellulosic biomass degradation. They are composed of a synthetic multimodular backbone protein, termed the scaffoldin, and a range of different chimeric docking enzymes that degrade polysaccharides. Over the years, several functional designer cellulosomes have been constructed. Since many parameters influence the efficiency of these multi-enzyme complexes, there is a need to optimise designer cellulosome architecture by testing combinatorial arrangements of docking enzyme and scaffoldin variants. However, the modular cloning procedures are tedious and cumbersome. RESULTS VersaTile is a combinatorial DNA assembly method, allowing the rapid construction and thus comparison of a range of modular proteins. Here, we present the extension of the VersaTile platform to facilitate the construction of designer cellulosomes. We have constructed a tile repository, composed of dockerins, cohesins, linkers, tags and enzymatically active modules. The developed toolbox allows us to efficiently create and optimise designer cellulosomes at an unprecedented speed. As a proof of concept, a trivalent designer cellulosome able to degrade the specific hemicellulose substrate, galactomannan, was constructed and optimised. The main factors influencing cellulosome efficiency were found to be the selected dockerins and linkers and the docking enzyme ratio on the scaffoldin. The optimised designer cellulosome was able to hydrolyse the galactomannan polysaccharide and release mannose and galactose monomers. CONCLUSION We have eliminated one of the main technical hurdles in the designer cellulosome field and anticipate the VersaTile platform to be a starting point in the development of more elaborate multi-enzyme complexes.
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Affiliation(s)
- Julie Vanderstraeten
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - Maria João Maurício da Fonseca
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - Philippe De Groote
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - Dennis Grimon
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - Hans Gerstmans
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium.,Laboratory for Biomolecular Discovery and Engineering, Department of Biology, VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001, Louvain, Belgium
| | - Amaranta Kahn
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 7610001, Rehovot, Israel.,Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Avenida General Norton de Matos, s/n, 4450-208, Matosinhos, Portugal
| | - Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 7610001, Rehovot, Israel.,Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, 8499000, Beer-Sheva, Israel
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 7610001, Rehovot, Israel.,Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, 8499000, Beer-Sheva, Israel
| | - Yves Briers
- Laboratory of Applied Biotechnology, Department of Biotechnology, Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium.
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10
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Brown JL, Swift CL, Mondo SJ, Seppala S, Salamov A, Singan V, Henrissat B, Drula E, Henske JK, Lee S, LaButti K, He G, Yan M, Barry K, Grigoriev IV, O'Malley MA. Co‑cultivation of the anaerobic fungus Caecomyces churrovis with Methanobacterium bryantii enhances transcription of carbohydrate binding modules, dockerins, and pyruvate formate lyases on specific substrates. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:234. [PMID: 34893091 PMCID: PMC8665504 DOI: 10.1186/s13068-021-02083-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/19/2021] [Indexed: 05/12/2023]
Abstract
Anaerobic fungi and methanogenic archaea are two classes of microorganisms found in the rumen microbiome that metabolically interact during lignocellulose breakdown. Here, stable synthetic co-cultures of the anaerobic fungus Caecomyces churrovis and the methanogen Methanobacterium bryantii (not native to the rumen) were formed, demonstrating that microbes from different environments can be paired based on metabolic ties. Transcriptional and metabolic changes induced by methanogen co-culture were evaluated in C. churrovis across a variety of substrates to identify mechanisms that impact biomass breakdown and sugar uptake. A high-quality genome of C. churrovis was obtained and annotated, which is the first sequenced genome of a non-rhizoid-forming anaerobic fungus. C. churrovis possess an abundance of CAZymes and carbohydrate binding modules and, in agreement with previous studies of early-diverging fungal lineages, N6-methyldeoxyadenine (6mA) was associated with transcriptionally active genes. Co-culture with the methanogen increased overall transcription of CAZymes, carbohydrate binding modules, and dockerin domains in co-cultures grown on both lignocellulose and cellulose and caused upregulation of genes coding associated enzymatic machinery including carbohydrate binding modules in family 18 and dockerin domains across multiple growth substrates relative to C. churrovis monoculture. Two other fungal strains grown on a reed canary grass substrate in co-culture with the same methanogen also exhibited high log2-fold change values for upregulation of genes encoding carbohydrate binding modules in families 1 and 18. Transcriptional upregulation indicated that co-culture of the C. churrovis strain with a methanogen may enhance pyruvate formate lyase (PFL) function for growth on xylan and fructose and production of bottleneck enzymes in sugar utilization pathways, further supporting the hypothesis that co-culture with a methanogen may enhance certain fungal metabolic functions. Upregulation of CBM18 may play a role in fungal-methanogen physical associations and fungal cell wall development and remodeling.
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Affiliation(s)
- Jennifer L Brown
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Candice L Swift
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Stephen J Mondo
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Susanna Seppala
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Asaf Salamov
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Vasanth Singan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Bernard Henrissat
- DTU Bioengineering, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Elodie Drula
- Architecture Et Fonction Des Macromolécules Biologiques, CNRS/Aix-Marseille University, Marseille, France
- INRAE USC1408, AFMB, 13009, Marseille, France
| | - John K Henske
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Samantha Lee
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Kurt LaButti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Guifen He
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Mi Yan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Michelle A O'Malley
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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11
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Clostridium thermocellum as a Promising Source of Genetic Material for Designer Cellulosomes: An Overview. Catalysts 2021. [DOI: 10.3390/catal11080996] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Plant biomass-based biofuels have gradually substituted for conventional energy sources thanks to their obvious advantages, such as renewability, huge quantity, wide availability, economic feasibility, and sustainability. However, to make use of the large amount of carbon sources stored in the plant cell wall, robust cellulolytic microorganisms are highly demanded to efficiently disintegrate the recalcitrant intertwined cellulose fibers to release fermentable sugars for microbial conversion. The Gram-positive, thermophilic, cellulolytic bacterium Clostridium thermocellum possesses a cellulolytic multienzyme complex termed the cellulosome, which has been widely considered to be nature’s finest cellulolytic machinery, fascinating scientists as an auspicious source of saccharolytic enzymes for biomass-based biofuel production. Owing to the supra-modular characteristics of the C. thermocellum cellulosome architecture, the cellulosomal components, including cohesin, dockerin, scaffoldin protein, and the plentiful cellulolytic and hemicellulolytic enzymes have been widely used for constructing artificial cellulosomes for basic studies and industrial applications. In addition, as the well-known microbial workhorses are naïve to biomass deconstruction, several research groups have sought to transform them from non-cellulolytic microbes into consolidated bioprocessing-enabling microbes. This review aims to update and discuss the current progress in these mentioned issues, point out their limitations, and suggest some future directions.
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12
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Frank BP, Smith C, Caudill ER, Lankone RS, Carlin K, Benware S, Pedersen JA, Fairbrother DH. Biodegradation of Functionalized Nanocellulose. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10744-10757. [PMID: 34282891 DOI: 10.1021/acs.est.0c07253] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nanocellulose has attracted widespread interest for applications in materials science and biomedical engineering due to its natural abundance, desirable physicochemical properties, and high intrinsic mineralizability (i.e., complete biodegradability). A common strategy to increase dispersibility in polymer matrices is to modify the hydroxyl groups on nanocellulose through covalent functionalization, but such modification strategies may affect the desirable biodegradation properties exhibited by pristine nanocellulose. In this study, cellulose nanofibrils (CNFs) functionalized with a range of esters, carboxylic acids, or ethers exhibited decreased rates and extents of mineralization by anaerobic and aerobic microbial communities compared to unmodified CNFs, with etherified CNFs exhibiting the highest level of recalcitrance. The decreased biodegradability of functionalized CNFs depended primarily on the degree of substitution at the surface of the material rather than within the bulk. This dependence on surface chemistry was attributed not only to the large surface area-to-volume ratio of nanocellulose but also to the prerequisite surface interaction by microorganisms necessary to achieve biodegradation. Results from this study highlight the need to quantify the type and coverage of surface substituents in order to anticipate their effects on the environmental persistence of functionalized nanocellulose.
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Affiliation(s)
- Benjamin P Frank
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
| | - Casey Smith
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
| | - Emily R Caudill
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Ronald S Lankone
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
| | - Katrina Carlin
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
| | - Sarah Benware
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Joel A Pedersen
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
- Departments of Soil Science and Civil & Environmental Engineering, University of Wisconsin-Madison, 1525 Observatory Drive, Madison, Wisconsin 53706, United States
| | - D Howard Fairbrother
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, Maryland 21218, United States
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13
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Vera AM, Galera-Prat A, Wojciechowski M, Różycki B, Laurents DV, Carrión-Vázquez M, Cieplak M, Tinnefeld P. Cohesin-dockerin code in cellulosomal dual binding modes and its allosteric regulation by proline isomerization. Structure 2021; 29:587-597.e8. [PMID: 33561387 DOI: 10.1016/j.str.2021.01.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 11/25/2020] [Accepted: 01/11/2021] [Indexed: 12/20/2022]
Abstract
Cellulose is the most abundant organic molecule on Earth and represents a renewable and practically everlasting feedstock for the production of biofuels and chemicals. Self-assembled owing to the high-affinity cohesin-dockerin interaction, cellulosomes are huge multi-enzyme complexes with unmatched efficiency in the degradation of recalcitrant lignocellulosic substrates. The recruitment of diverse dockerin-borne enzymes into a multicohesin protein scaffold dictates the three-dimensional layout of the complex, and interestingly two alternative binding modes have been proposed. Using single-molecule fluorescence resonance energy transfer and molecular simulations on a range of cohesin-dockerin pairs, we directly detect varying distributions between these binding modes that follow a built-in cohesin-dockerin code. Surprisingly, we uncover a prolyl isomerase-modulated allosteric control mechanism, mediated by the isomerization state of a single proline residue, which regulates the distribution and kinetics of binding modes. Overall, our data provide a novel mechanistic understanding of the structural plasticity and dynamics of cellulosomes.
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Affiliation(s)
- Andrés Manuel Vera
- Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13 Haus E, 81377 München, Germany.
| | - Albert Galera-Prat
- Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, 90014 Oulu, Finland
| | - Michał Wojciechowski
- Institute of Physics, Polish Academy of Sciences, Al. Lotników, 32/46, 02-668 Warsaw, Poland
| | - Bartosz Różycki
- Institute of Physics, Polish Academy of Sciences, Al. Lotników, 32/46, 02-668 Warsaw, Poland
| | - Douglas V Laurents
- Instituto de Química Física "Rocasolano", CSIC, C/ Serrano 119, 28006 Madrid, Spain
| | | | - Marek Cieplak
- Institute of Physics, Polish Academy of Sciences, Al. Lotników, 32/46, 02-668 Warsaw, Poland
| | - Philip Tinnefeld
- Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13 Haus E, 81377 München, Germany
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14
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Research progress and the biotechnological applications of multienzyme complex. Appl Microbiol Biotechnol 2021; 105:1759-1777. [PMID: 33564922 DOI: 10.1007/s00253-021-11121-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/07/2021] [Accepted: 01/16/2021] [Indexed: 11/26/2022]
Abstract
The multienzyme complex system has become a research focus in synthetic biology due to its highly efficient overall catalytic ability and has been applied to various fields. Multienzyme complexes are formed by cascading complexes, which are multiple functionally related enzymes that continuously and efficiently catalyze the production of substrates. Compared with current mainstream microbial cell catalytic systems, in vitro multienzyme molecular machines have many advantages, such as fewer side reactions, a high product yield, a fast reaction speed, easy product separation, a tolerable toxic environment, and robust system operability, showing increasing competitiveness in the field of biomanufacturing. In this review, the research progress of multienzyme complexes in nature and multienzyme cascades in vivo or in vitro will be introduced, and the discovered enzyme cascades concerning scaffolding proteins will also be discussed. This review is expected to provide a more theoretical basis for the modification of multienzyme complexes and broaden their application in the field of synthetic biology. KEY POINTS: • The cascade reactions of some natural multienzyme complexes are reviewed. • The main approaches of constructing artificial multienzyme complexes are summarized. • The structure and application of cellulosomes are discussed and prospected.
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15
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Vanderstraeten J, Briers Y. Synthetic protein scaffolds for the colocalisation of co-acting enzymes. Biotechnol Adv 2020; 44:107627. [DOI: 10.1016/j.biotechadv.2020.107627] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 08/17/2020] [Accepted: 08/25/2020] [Indexed: 02/06/2023]
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16
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Dvořák P, Bayer EA, de Lorenzo V. Surface Display of Designer Protein Scaffolds on Genome-Reduced Strains of Pseudomonas putida. ACS Synth Biol 2020; 9:2749-2764. [PMID: 32877604 DOI: 10.1021/acssynbio.0c00276] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The bacterium Pseudomonas putida KT2440 is gaining considerable interest as a microbial platform for biotechnological valorization of polymeric organic materials, such as lignocellulosic residues or plastics. However, P. putida on its own cannot make much use of such complex substrates, mainly because it lacks an efficient extracellular depolymerizing apparatus. We seek to address this limitation by adopting a recombinant cellulosome strategy for this host. In this work, we report an essential step in this endeavor-a display of designer enzyme-anchoring protein "scaffoldins", encompassing cohesin binding domains from divergent cellulolytic bacterial species on the P. putida surface. Two P. putida chassis strains, EM42 and EM371, with streamlined genomes and differences in the composition of the outer membrane were employed in this study. Scaffoldin variants were optimally delivered to their surface with one of four tested autotransporter systems (Ag43 from Escherichia coli), and the efficient display was confirmed by extracellular attachment of chimeric β-glucosidase and fluorescent proteins. Our results not only highlight the value of cell surface engineering for presentation of recombinant proteins on the envelope of Gram-negative bacteria but also pave the way toward designer cellulosome strategies tailored for P. putida.
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Affiliation(s)
- Pavel Dvořák
- Department of Experimental Biology (Section of Microbiology), Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Víctor de Lorenzo
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología CNB-CSIC, Cantoblanco, Darwin 3, 28049 Madrid, Spain
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17
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Galera-Prat A, Vera AM, Moraïs S, Vazana Y, Bayer EA, Carrión-Vázquez M. Impact of scaffoldin mechanostability on cellulosomal activity. Biomater Sci 2020; 8:3601-3610. [PMID: 32232253 DOI: 10.1039/c9bm02052g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lignocellulose is the most abundant renewable carbon source in the biosphere. However, the main bottleneck in its conversion to produce second generation biofuels is the saccharification step: the hydrolysis of lignocellulosic material into soluble fermentable sugars. Some anaerobic bacteria have developed an extracellular multi-enzyme complex called the cellulosome that efficiently degrades cellulosic substrates. Cellulosome complexes rely on enzyme-integrating scaffoldins that are large non-catalytic scaffolding proteins comprising several cohesin modules and additional functional modules that mediate the anchoring of the complex to the cell surface and the specific binding to its cellulosic substrate. It was proposed that mechanical forces may affect the cohesins positioned between the cell- and cellulose-anchoring points in the so-called connecting region. Consequently, the mechanical resistance of cohesins within the scaffoldin is of great importance, both to understand cellulosome function and as a parameter of industrial interest, to better mimic natural complexes through the use of the established designer cellulosome technology. Here we study how the mechanical stability of cohesins in a scaffoldin affects the enzymatic activity of a cellulosome. We found that when a cohesin of low mechanical stability is positioned in the connecting region of a scaffoldin, the activity of the resulting cellulosome is reduced as opposed to a cohesin of higher mechanical stability. This observation directly relates mechanical stability of the scaffoldin-borne cohesins to cellulosome activity and provides a rationale for the design of artificial cellulosomes for industrial applications, by incorporating mechanical stability as a new industrial parameter in the biotechnology toolbox.
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Affiliation(s)
- Albert Galera-Prat
- Instituto Cajal, Department of Molecular, Cellular and Developmental Neurobiology. IC-CSIC, Avenida Doctor Arce 37, 28002 Madrid, Spain.
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18
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Enjalbert T, De La Mare M, Roblin P, Badruna L, Vernet T, Dumon C, Montanier CY. Characterisation of the Effect of the Spatial Organisation of Hemicellulases on the Hydrolysis of Plant Biomass Polymer. Int J Mol Sci 2020; 21:ijms21124360. [PMID: 32575393 PMCID: PMC7353053 DOI: 10.3390/ijms21124360] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/15/2020] [Accepted: 06/15/2020] [Indexed: 01/21/2023] Open
Abstract
Synergism between enzymes is of crucial importance in cell metabolism. This synergism occurs often through a spatial organisation favouring proximity and substrate channelling. In this context, we developed a strategy for evaluating the impact of the geometry between two enzymes involved in nature in the recycling of the carbon derived from plant cell wall polymers. By using an innovative covalent association process using two protein fragments, Jo and In, we produced two bi-modular chimeric complexes connecting a xylanase and a xylosidase, involved in the deconstruction of xylose-based plant cell wall polymer. We first show that the intrinsic activity of the individual enzymes was preserved. Small Angle X-rays Scattering (SAXS) analysis of the complexes highlighted two different spatial organisations in solution, affecting both the distance between the enzymes (53 Å and 28 Å) and the distance between the catalytic pockets (94 Å and 75 Å). Reducing sugar and HPAEC-PAD analysis revealed different behaviour regarding the hydrolysis of Beechwood xylan. After 24 h of hydrolysis, one complex was able to release a higher amount of reducing sugar compare to the free enzymes (i.e., 15,640 and 14,549 µM of equivalent xylose, respectively). However, more interestingly, the two complexes were able to release variable percentages of xylooligosaccharides compared to the free enzymes. The structure of the complexes revealed some putative steric hindrance, which impacted both enzymatic efficiency and the product profile. This report shows that controlling the spatial geometry between two enzymes would help to better investigate synergism effect within complex multi-enzymatic machinery and control the final product.
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Affiliation(s)
- Thomas Enjalbert
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
| | - Marion De La Mare
- Toulouse White Biotechnology, UMS INRA 1337, UMS CNRS 3582, Institut National des Sciences Appliquées de Toulouse, 31077 Toulouse, France;
| | - Pierre Roblin
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31077 Toulouse, France;
| | - Louise Badruna
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
| | - Thierry Vernet
- Institut de Biologie Structurale, Univ., Grenoble Alpes, CEA, CNRS, IBS, F-38000 Grenoble, France;
| | - Claire Dumon
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
| | - Cédric Y. Montanier
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
- Correspondence: ; Tel.: +33-(0)5-61-55-97-13
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19
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Kahn A, Moraïs S, Chung D, Sarai NS, Hengge NN, Kahn A, Himmel ME, Bayer EA, Bomble YJ. Glycosylation of hyperthermostable designer cellulosome components yields enhanced stability and cellulose hydrolysis. FEBS J 2020; 287:4370-4388. [DOI: 10.1111/febs.15251] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 01/06/2020] [Accepted: 02/14/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Amaranta Kahn
- Department of Biomolecular Sciences The Weizmann Institute of Science Rehovot Israel
| | - Sarah Moraïs
- Department of Biomolecular Sciences The Weizmann Institute of Science Rehovot Israel
- Faculty of Natural Sciences Ben‐Gurion University of the Negev Beer‐Sheva Israel
| | - Daehwan Chung
- Biosciences Center National Renewable Energy Laboratory Golden CO USA
| | - Nicholas S. Sarai
- Biosciences Center National Renewable Energy Laboratory Golden CO USA
| | - Neal N. Hengge
- Biosciences Center National Renewable Energy Laboratory Golden CO USA
| | - Audrey Kahn
- Department of Biomolecular Sciences The Weizmann Institute of Science Rehovot Israel
| | - Michael E. Himmel
- Biosciences Center National Renewable Energy Laboratory Golden CO USA
| | - Edward A. Bayer
- Department of Biomolecular Sciences The Weizmann Institute of Science Rehovot Israel
| | - Yannick J. Bomble
- Biosciences Center National Renewable Energy Laboratory Golden CO USA
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20
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Vita N, Borne R, Fierobe HP. Cell-surface exposure of a hybrid 3-cohesin scaffoldin allowing the functionalization of Escherichia coli envelope. Biotechnol Bioeng 2020; 117:626-636. [PMID: 31814100 DOI: 10.1002/bit.27242] [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] [Received: 10/18/2019] [Revised: 11/27/2019] [Accepted: 11/30/2019] [Indexed: 12/26/2022]
Abstract
Cellulosomes are large plant cell wall degrading complexes secreted by some anaerobic bacteria. They are typically composed of a major scaffolding protein containing multiple receptors called cohesins, which tightly anchor a small complementary module termed dockerin harbored by the cellulosomal enzymes. In the present study, we have successfully cell surface exposed in Escherichia coli a hybrid scaffoldin, Scaf6, fused to the curli protein CsgA, the latter is known to polymerize at the surface of E. coli to form extracellular fibers under stressful environmental conditions. The C-terminal part of the chimera encompasses the hybrid scaffoldin composed of three cohesins from different bacterial origins and a carbohydrate-binding module targeting insoluble cellulose. Using three cellulases hosting the complementary dockerin modules and labeled with different fluorophores, we have shown that the hybrid scaffoldin merged to CsgA is massively exposed at the cell surface of E. coli and that each cohesin module is fully operational. Altogether these data open a new route for a series of biotechnological applications exploiting the cell-surface exposure of CsgA-Scaf6 in various industrial sectors such as vaccines, biocatalysts or bioremediation, simply by grafting the small dockerin module to the desired proteins before incubation with the engineered E. coli.
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Affiliation(s)
- Nicolas Vita
- Aix-Marseille université, CNRS, LCB, Marseille, France
| | - Romain Borne
- Aix-Marseille université, CNRS, LCB, Marseille, France
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21
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Borne R, Dao Ti MU, Fierobe HP, Vita N, Tardif C, Pagès S. Catalytic subunit exchanges in the cellulosomes produced by Ruminiclostridium cellulolyticum suggest unexpected dynamics and adaptability of their enzymatic composition. FEBS J 2019; 287:2544-2559. [PMID: 31769922 DOI: 10.1111/febs.15155] [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: 07/17/2019] [Revised: 10/22/2019] [Accepted: 11/22/2019] [Indexed: 11/29/2022]
Abstract
Cellulosomes are complex nanomachines produced by cellulolytic anaerobic bacteria such as Ruminiclostridium cellulolyticum (formerly known as Clostridium cellulolyticum). Cellulosomes are composed of a scaffoldin protein displaying several cohesin modules on which enzymatic components can bind to through their dockerin module. Although cellulosomes have been studied for decades, very little is known about the dynamics of complex assembly. We have investigated the ability of some dockerin-bearing enzymes to chase the catalytic subunits already bound onto a miniscaffoldin displaying a single cohesin. The stability of the preassembled enzyme-scaffoldin complex appears to depend on the nature of the dockerin, and we have identified a key position in the dockerin sequence that is involved in the stability of the complex with the cohesin. Depending on the residue occupying this position, the dockerin can establish with the cohesin partner either a nearly irreversible or a reversible interaction, independently of the catalytic domain associated with the dockerin. Site-directed mutagenesis of this residue can convert a dockerin able to form a highly stable complex with the miniscaffoldin into a reversible complex forming one and vice versa. We also show that refunctionalization can occur with natural purified cellulosomes. Altogether, our results shed light on the dynamics of cellulosomes, especially their capacity to be remodeled even after their assembly is 'achieved', suggesting an unforeseen adaptability of their enzymatic composition over time.
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22
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Ribeiro LF, Amarelle V, Alves LDF, Viana de Siqueira GM, Lovate GL, Borelli TC, Guazzaroni ME. Genetically Engineered Proteins to Improve Biomass Conversion: New Advances and Challenges for Tailoring Biocatalysts. Molecules 2019; 24:molecules24162879. [PMID: 31398877 PMCID: PMC6719137 DOI: 10.3390/molecules24162879] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 07/30/2019] [Accepted: 08/06/2019] [Indexed: 01/02/2023] Open
Abstract
Protein engineering emerged as a powerful approach to generate more robust and efficient biocatalysts for bio-based economy applications, an alternative to ecologically toxic chemistries that rely on petroleum. On the quest for environmentally friendly technologies, sustainable and low-cost resources such as lignocellulosic plant-derived biomass are being used for the production of biofuels and fine chemicals. Since most of the enzymes used in the biorefinery industry act in suboptimal conditions, modification of their catalytic properties through protein rational design and in vitro evolution techniques allows the improvement of enzymatic parameters such as specificity, activity, efficiency, secretability, and stability, leading to better yields in the production lines. This review focuses on the current application of protein engineering techniques for improving the catalytic performance of enzymes used to break down lignocellulosic polymers. We discuss the use of both classical and modern methods reported in the literature in the last five years that allowed the boosting of biocatalysts for biomass degradation.
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Affiliation(s)
- Lucas Ferreira Ribeiro
- Department of Biology, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-901, Brazil.
| | - Vanesa Amarelle
- Department of Microbial Biochemistry and Genomics, Biological Research Institute Clemente Estable, Montevideo, PC 11600, Uruguay
| | - Luana de Fátima Alves
- Department of Biochemistry and Immunology, Faculdade de Medicina de Ribeirão Preto, University of São Paulo, Ribeirão Preto 14049-900, Brazil
| | | | - Gabriel Lencioni Lovate
- Department of Biochemistry and Immunology, Faculdade de Medicina de Ribeirão Preto, University of São Paulo, Ribeirão Preto 14049-900, Brazil
| | - Tiago Cabral Borelli
- Department of Biology, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-901, Brazil
| | - María-Eugenia Guazzaroni
- Department of Biology, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-901, Brazil.
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23
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Vita N, Borne R, Perret S, de Philip P, Fierobe HP. Turning a potent family-9 free cellulase into an operational cellulosomal component and vice versa. FEBS J 2019; 286:3359-3373. [PMID: 31004451 DOI: 10.1111/febs.14858] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/18/2019] [Accepted: 04/16/2019] [Indexed: 11/29/2022]
Abstract
Ruminiclostridium cellulolyticum and Lachnoclostridium phytofermentans are cellulolytic clostridia either producing extracellular multienzymatic complexes termed cellulosomes or secreting free cellulases respectively. In the free state, the cellulase Cel9A secreted by L. phytofermentans is much more active on crystalline cellulose than any cellulosomal family-9 enzyme produced by R. cellulolyticum. Nevertheless, the incorporation of Cel9A in vitro in hybrid cellulosomes was formerly shown to generate artificial complexes with altered activity, whereas its incorporation in vivo in native R. cellulolyticum cellulosomes resulted in a strain displaying a weakened cellulolytic phenotype. In this study, we investigated why Cel9A is so potent in the free state but functions poorly as a cellulosomal component, in contrast to the most similar enzyme synthesized by R. cellulolyticum, Cel9G, weakly active in the free state but whose activity on crystalline cellulose is drastically increased in cellulosomes. We show that the removal of the C-terminal moiety of Cel9A encompassing the two X2 modules and the family-3b carbohydrate binding module (CBM3b), reduces its activity on crystalline cellulose. Grafting a dockerin module further diminishes the activity, but this truncated cellulosomal form of Cel9A displays important synergies in hybrid cellulosomes with the pivotal family-48 cellulosomal enzyme of R. cellulolyticum. The exact inverse approach was applied to the cellulosomal Cel9G. Grafting the two X2 modules and the CBM3b of Cel9A to Cel9G strongly increases its activity on crystalline cellulose, to reach Cel9A activity levels. Altogether these data emphasize the specific features required to generate an efficient free or cellulosomal family-9 cellulase.
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24
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Kahn A, Moraïs S, Galanopoulou AP, Chung D, Sarai NS, Hengge N, Hatzinikolaou DG, Himmel ME, Bomble YJ, Bayer EA. Creation of a functional hyperthermostable designer cellulosome. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:44. [PMID: 30858881 PMCID: PMC6394049 DOI: 10.1186/s13068-019-1386-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 02/20/2019] [Indexed: 05/28/2023]
Abstract
BACKGROUND Renewable energy has become a field of high interest over the past decade, and production of biofuels from cellulosic substrates has a particularly high potential as an alternative source of energy. Industrial deconstruction of biomass, however, is an onerous, exothermic process, the cost of which could be decreased significantly by use of hyperthermophilic enzymes. An efficient way of breaking down cellulosic substrates can also be achieved by highly efficient enzymatic complexes called cellulosomes. The modular architecture of these multi-enzyme complexes results in substrate targeting and proximity-based synergy among the resident enzymes. However, cellulosomes have not been observed in hyperthermophilic bacteria. RESULTS Here, we report the design and function of a novel hyperthermostable "designer cellulosome" system, which is stable and active at 75 °C. Enzymes from Caldicellulosiruptor bescii, a highly cellulolytic hyperthermophilic anaerobic bacterium, were selected and successfully converted to the cellulosomal mode by grafting onto them divergent dockerin modules that can be inserted in a precise manner into a thermostable chimaeric scaffoldin by virtue of their matching cohesins. Three pairs of cohesins and dockerins, selected from thermophilic microbes, were examined for their stability at extreme temperatures and were determined stable at 75 °C for at least 72 h. The resultant hyperthermostable cellulosome complex exhibited the highest levels of enzymatic activity on microcrystalline cellulose at 75 °C, compared to those of previously reported designer cellulosome systems and the native cellulosome from Clostridium thermocellum. CONCLUSION The functional hyperthermophilic platform fulfills the appropriate physico-chemical properties required for exothermic processes. This system can thus be adapted for other types of thermostable enzyme systems and could serve as a basis for a variety of cellulolytic and non-cellulolytic industrial objectives at high temperatures.
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Affiliation(s)
- Amaranta Kahn
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 7610001 Rehovot, Israel
| | - Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 7610001 Rehovot, Israel
- Faculty of Natural Sciences, Ben-Gurion University of the Negev, 8499000 Beer-Sheva, Israel
| | - Anastasia P. Galanopoulou
- Microbiology Group, Faculty of Biology, National and Kapodistrian University of Athens, Zografou Campus, 15784 Athens, Greece
| | - Daehwan Chung
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
| | - Nicholas S. Sarai
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
- Present Address: Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Neal Hengge
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
| | - Dimitris G. Hatzinikolaou
- Microbiology Group, Faculty of Biology, National and Kapodistrian University of Athens, Zografou Campus, 15784 Athens, Greece
| | - Michael E. Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
| | - Yannick J. Bomble
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
| | - Edward A. Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 7610001 Rehovot, Israel
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Liang X, Whitham JM, Holwerda EK, Shao X, Tian L, Wu YW, Lombard V, Henrissat B, Klingeman DM, Yang ZK, Podar M, Richard TL, Elkins JG, Brown SD, Lynd LR. Development and characterization of stable anaerobic thermophilic methanogenic microbiomes fermenting switchgrass at decreasing residence times. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:243. [PMID: 30202438 PMCID: PMC6126044 DOI: 10.1186/s13068-018-1238-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 08/27/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Anaerobic fermentation of lignocellulose occurs in both natural and managed environments, and is an essential part of the carbon cycle as well as a promising route to sustainable production of fuels and chemicals. Lignocellulose solubilization by mixed microbiomes is important in these contexts. RESULTS Here, we report the development of stable switchgrass-fermenting enrichment cultures maintained at various residence times and moderately high (55 °C) temperatures. Anaerobic microbiomes derived from a digester inoculum were incubated at 55 °C and fed semi-continuously with medium containing 30 g/L mid-season harvested switchgrass to achieve residence times (RT) of 20, 10, 5, and 3.3 days. Stable, time-invariant cellulolytic methanogenic cultures with minimal accumulation of organic acids were achieved for all RTs. Fractional carbohydrate solubilization was 0.711, 0.654, 0.581 and 0.538 at RT = 20, 10, 5 and 3.3 days, respectively, and glucan solubilization was proportional to xylan solubilization at all RTs. The rate of solubilization was described well by the equation r = k(C - C0fr), where C represents the concentration of unutilized carbohydrate, C0 is the concentration of carbohydrate (cellulose and hemicellulose) entering the bioreactor and fr is the extrapolated fraction of entering carbohydrate that is recalcitrant at infinite residence time. The 3.3 day RT is among the shortest RT reported for stable thermophilic, methanogenic digestion of a lignocellulosic feedstock. 16S rDNA phylotyping and metagenomic analyses were conducted to characterize the effect of RT on community dynamics and to infer functional roles in the switchgrass to biogas conversion to the various microbial taxa. Firmicutes were the dominant phylum, increasing in relative abundance from 54 to 96% as RT decreased. A Clostridium clariflavum strain with genetic markers for xylose metabolism was the most abundant lignocellulose-solubilizing bacterium. A Thermotogae (Defluviitoga tunisiensis) was the most abundant bacterium in switchgrass digesters at RT = 20 days but decreased in abundance at lower RTs as did multiple Chloroflexi. Synergistetes and Euryarchaeota were present at roughly constant levels over the range of RTs examined. CONCLUSIONS A system was developed in which stable methanogenic steady-states were readily obtained with a particulate biomass feedstock, mid-season switchgrass, at laboratory (1 L) scale. Characterization of the extent and rate of carbohydrate solubilization in combination with 16S rDNA and metagenomic sequencing provides a multi-dimensional view of performance, species composition, glycoside hydrolases, and metabolic function with varying residence time. These results provide a point of reference and guidance for future studies and organism development efforts involving defined cultures.
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Affiliation(s)
- Xiaoyu Liang
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Jason M. Whitham
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Evert K. Holwerda
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Xiongjun Shao
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Liang Tian
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Yu-Wei Wu
- Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei Medical University, Taipei, 106 Taiwan
| | - Vincent Lombard
- CNRS, UMR 7257, Aix-Marseille University, 13288 Marseille, France
- INRA, USC 1408 AFMB, 13288 Marseille, France
| | - Bernard Henrissat
- CNRS, UMR 7257, Aix-Marseille University, 13288 Marseille, France
- INRA, USC 1408 AFMB, 13288 Marseille, France
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Dawn M. Klingeman
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Zamin K. Yang
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Mircea Podar
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Tom L. Richard
- Department of Agricultural and Biological Engineering, The Pennsylvania State University, University Park, State College, PA 16802 USA
| | - James G. Elkins
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Steven D. Brown
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
- Present Address: LanzaTech, Inc., Skokie, IL 60077 USA
| | - Lee R. Lynd
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
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Bugada LF, Smith MR, Wen F. Engineering Spatially Organized Multienzyme Assemblies for Complex Chemical Transformation. ACS Catal 2018. [DOI: 10.1021/acscatal.8b01883] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Luke F. Bugada
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Mason R. Smith
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Fei Wen
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
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27
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Banerjee A, Howarth M. Nanoteamwork: covalent protein assembly beyond duets towards protein ensembles and orchestras. Curr Opin Biotechnol 2018; 51:16-23. [DOI: 10.1016/j.copbio.2017.10.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/23/2017] [Indexed: 11/16/2022]
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Stern J, Moraïs S, Ben-David Y, Salama R, Shamshoum M, Lamed R, Shoham Y, Bayer EA, Mizrahi I. Assembly of Synthetic Functional Cellulosomal Structures onto the Cell Surface of Lactobacillus plantarum, a Potent Member of the Gut Microbiome. Appl Environ Microbiol 2018; 84:e00282-18. [PMID: 29453253 PMCID: PMC5881048 DOI: 10.1128/aem.00282-18] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 02/08/2018] [Indexed: 12/27/2022] Open
Abstract
Heterologous display of enzymes on microbial cell surfaces is an extremely desirable approach, since it enables the engineered microbe to interact directly with the plant wall extracellular polysaccharide matrix. In recent years, attempts have been made to endow noncellulolytic microbes with genetically engineered cellulolytic capabilities for improved hydrolysis of lignocellulosic biomass and for advanced probiotics. Thus far, however, owing to the hurdles encountered in secreting and assembling large, intricate complexes on the bacterial cell wall, only free cellulases or relatively simple cellulosome assemblies have been introduced into live bacteria. Here, we employed the "adaptor scaffoldin" strategy to compensate for the low levels of protein displayed on the bacterial cell surface. That strategy mimics natural elaborated cellulosome architectures, thus exploiting the exponential features of their Lego-like combinatorics. Using this approach, we produced several bacterial consortia of Lactobacillus plantarum, a potent gut microbe which provides a very robust genetic framework for lignocellulosic degradation. We successfully engineered surface display of large, fully active self-assembling cellulosomal complexes containing an unprecedented number of catalytic subunits all produced in vivo by the cell consortia. Our results demonstrate that the enzyme stability and performance of the cellulosomal machinery, which are superior to those seen with the equivalent secreted free enzyme system, and the high cellulase-to-xylanase ratios proved beneficial for efficient degradation of wheat straw.IMPORTANCE The multiple benefits of lactic acid bacteria are well established in health and industry. Here we present an approach designed to extensively increase the cell surface display of proteins via successive assembly of interactive components. Our findings present a stepping stone toward proficient engineering of Lactobacillus plantarum, a widespread, environmentally important bacterium and potent microbiome member, for improved degradation of lignocellulosic biomass and advanced probiotics.
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Affiliation(s)
- Johanna Stern
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
- Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Yonit Ben-David
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Rachel Salama
- Department of Biotechnology and Food Engineering, The Technion Israel Institute of Technology, Haifa, Israel
| | - Melina Shamshoum
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Raphael Lamed
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Ramat Aviv, Israel
| | - Yuval Shoham
- Department of Biotechnology and Food Engineering, The Technion Israel Institute of Technology, Haifa, Israel
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Itzhak Mizrahi
- Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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Desvaux M, Candela T, Serror P. Surfaceome and Proteosurfaceome in Parietal Monoderm Bacteria: Focus on Protein Cell-Surface Display. Front Microbiol 2018; 9:100. [PMID: 29491848 PMCID: PMC5817068 DOI: 10.3389/fmicb.2018.00100] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 01/16/2018] [Indexed: 12/12/2022] Open
Abstract
The cell envelope of parietal monoderm bacteria (archetypal Gram-positive bacteria) is formed of a cytoplasmic membrane (CM) and a cell wall (CW). While the CM is composed of phospholipids, the CW is composed at least of peptidoglycan (PG) covalently linked to other biopolymers, such as teichoic acids, polysaccharides, and/or polyglutamate. Considering the CW is a porous structure with low selective permeability contrary to the CM, the bacterial cell surface hugs the molecular figure of the CW components as a well of the external side of the CM. While the surfaceome corresponds to the totality of the molecules found at the bacterial cell surface, the proteinaceous complement of the surfaceome is the proteosurfaceome. Once translocated across the CM, secreted proteins can either be released in the extracellular milieu or exposed at the cell surface by associating to the CM or the CW. Following the gene ontology (GO) for cellular components, cell-surface proteins at the CM can either be integral (GO: 0031226), i.e., the integral membrane proteins, or anchored to the membrane (GO: 0046658), i.e., the lipoproteins. At the CW (GO: 0009275), cell-surface proteins can be covalently bound, i.e., the LPXTG-proteins, or bound through weak interactions to the PG or wall polysaccharides, i.e., the cell wall binding proteins. Besides monopolypeptides, some proteins can associate to each other to form supramolecular protein structures of high molecular weight, namely the S-layer, pili, flagella, and cellulosomes. After reviewing the cell envelope components and the different molecular mechanisms involved in protein attachment to the cell envelope, perspectives in investigating the proteosurfaceome in parietal monoderm bacteria are further discussed.
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Affiliation(s)
- Mickaël Desvaux
- Université Clermont Auvergne, INRA, UMR454 MEDiS, Clermont-Ferrand, France
| | - Thomas Candela
- EA4043 Unité Bactéries Pathogènes et Santé, Châtenay-Malabry, France
| | - Pascale Serror
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
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30
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Han Z, Su WW. Intein-mediated assembly of tunable scaffoldins for facile synthesis of designer cellulosomes. Appl Microbiol Biotechnol 2018; 102:1331-1342. [PMID: 29275429 DOI: 10.1007/s00253-017-8701-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 11/05/2017] [Accepted: 12/04/2017] [Indexed: 01/26/2023]
Abstract
In this study, extended artificial scaffoldins possessing multiple cohesin modules were created in vivo by employing split-intein-mediated protein ligation. Artificial scaffoldins having one Clostridium thermocellum cohesin (Coht), one carbohydrate binding module (CBM) from Clostridium cellulolyticum scaffolding protein CipC, and one to five cohesins (Cohc) derived from CipC, were assembled. These scaffoldins were used to assemble cellulosomal enzyme complexes for investigating the interplay among endoglucanase, exoglucanase, and scaffoldin-borne CBM, on the hydrolysis of a model microcrystalline cellulose substrate, Avicel. The cellulosomal complexes were assembled in vitro by incubating recombinant C. thermocellum endoglucanase (At) and C. cellulolyticum exoglucanase (Ec), with the various artificial scaffoldins. Under a fixed total cellulase concentration, improved hydrolysis is noted by recruiting both Ec and At on the same scaffoldin, for all scaffoldins tested, compared with free cellulases. The improvement is more profound with scaffoldins having a higher Cohc/Coht ratio (i.e., increased Ec/At ratio). Furthermore, among scaffoldins having the same Cohc/Coht ratio, highest rates of Avicel hydrolysis are noted when Coht, and hence an endoglucanase, is situated next to the CBM and not flanked by Cohc. These results point to the importance of using scaffoldins with sufficiently high numbers of cohesin units to achieve an optimal exo-/endo-glucanase ratio to create efficient designer cellulosomes. Furthermore, intein-trans-splicing is proven here to be an effective method for assembling complex scaffoldins and more intricate cellulosomes.
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Affiliation(s)
- Zhenlin Han
- Department of Molecular Biosciences and Bioengineering, University of Hawaii, Honolulu, HI, 96822, USA
| | - Wei Wen Su
- Department of Molecular Biosciences and Bioengineering, University of Hawaii, Honolulu, HI, 96822, USA.
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31
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Orłowski A, Artzi L, Cazade PA, Gunnoo M, Bayer EA, Thompson D. On the distinct binding modes of expansin and carbohydrate-binding module proteins on crystalline and nanofibrous cellulose: implications for cellulose degradation by designer cellulosomes. Phys Chem Chem Phys 2018. [DOI: 10.1039/c7cp07764e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Transformation of cellulose into monosaccharides can be achieved by hydrolysis of the cellulose chains, carried out by a special group of enzymes known as cellulases.
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Affiliation(s)
- Adam Orłowski
- Department of Physics
- Bernal Institute
- University of Limerick
- Ireland
| | - Lior Artzi
- Department of Biomolecular Sciences
- The Weizmann Institute of Science
- Rehovot
- Israel
| | | | | | - Edward A. Bayer
- Department of Biomolecular Sciences
- The Weizmann Institute of Science
- Rehovot
- Israel
| | - Damien Thompson
- Department of Physics
- Bernal Institute
- University of Limerick
- Ireland
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Abstract
Cellulose deconstruction is achieved in nature through two main enzymatic paradigms, i.e., free enzymes and enzymatic complexes (called cellulosomes). Gaining insights into the mechanism of action and synergy among the different cellulases is of high interest, notably in the field of renewable energy, and specifically, for the conversion of cellulosic biomass to soluble sugars, en route to biofuels. In this context, designer cellulosomes are artificially assembled, chimaeric protein complexes that are used as a tool to comparatively study cellulose degradation by different enzymatic paradigms, and could also serve to improve cellulose deconstruction. Various molecular biology techniques are employed in order to design and engineer the various components of designer cellulosomes. In this chapter, we describe the cloning processes through which the appropriate modules are selected and assembled at the molecular level.
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Affiliation(s)
- Amaranta Kahn
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel.
| | - Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
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Pan-Cellulosomics of Mesophilic Clostridia: Variations on a Theme. Microorganisms 2017; 5:microorganisms5040074. [PMID: 29156585 PMCID: PMC5748583 DOI: 10.3390/microorganisms5040074] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/14/2017] [Accepted: 11/16/2017] [Indexed: 11/17/2022] Open
Abstract
The bacterial cellulosome is an extracellular, multi-enzyme machinery, which efficiently depolymerizes plant biomass by degrading plant cell wall polysaccharides. Several cellulolytic bacteria have evolved various elaborate modular architectures of active cellulosomes. We present here a genome-wide analysis of a dozen mesophilic clostridia species, including both well-studied and yet-undescribed cellulosome-producing bacteria. We first report here, the presence of cellulosomal elements, thus expanding our knowledge regarding the prevalence of the cellulosomal paradigm in nature. We explored the genomic organization of key cellulosome components by comparing the cellulosomal gene clusters in each bacterial species, and the conserved sequence features of the specific cellulosomal modules (cohesins and dockerins), on the background of their phylogenetic relationship. Additionally, we performed comparative analyses of the species-specific repertoire of carbohydrate-degrading enzymes for each of the clostridial species, and classified each cellulosomal enzyme into a specific CAZy family, thus indicating their putative enzymatic activity (e.g., cellulases, hemicellulases, and pectinases). Our work provides, for this large group of bacteria, a broad overview of the blueprints of their multi-component cellulosomal complexes. The high similarity of their scaffoldin clusters and dockerin-based recognition residues suggests a common ancestor, and/or extensive horizontal gene transfer, and potential cross-species recognition. In addition, the sporadic spatial organization of the numerous dockerin-containing genes in several of the genomes, suggests the importance of the cellulosome paradigm in the given bacterial species. The information gained in this work may be utilized directly or developed further by genetically engineering and optimizing designer cellulosome systems for enhanced biotechnological biomass deconstruction and biofuel production.
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Setter-Lamed E, Moraïs S, Stern J, Lamed R, Bayer EA. Modular Organization of the Thermobifida fusca Exoglucanase Cel6B Impacts Cellulose Hydrolysis and Designer Cellulosome Efficiency. Biotechnol J 2017; 12. [PMID: 28901714 DOI: 10.1002/biot.201700205] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 09/06/2017] [Indexed: 11/09/2022]
Abstract
Cellulose deconstruction can be achieved by three distinct enzymatic paradigms: free enzymes, multifunctional enzymes, and self-assembled, multi-enzyme complexes (cellulosomes). To study their comparative efficiency, the simple and efficient cellulolytic system of the aerobic bacterium, Thermobifida fusca, is developed as an enzymatic model. In previous studies, most of its cellulases are successfully converted to the cellulosomal mode and exhibited high cellulolytic activities, except for Cel6B, a key exoglucanase of the T. fusca enzymatic system. Here, the impact of the modular organization of Cel6B on enzymatic activity is investigated. The position of the cellulose-binding module (CBM), its family and linker segment are shown to affect activity. Surprisingly, exchange of the native family-2 CBM to family-3 generates an increase in Cel6B activity on cellulosic substrates. Conversion of Cel6B to the cellulosomal mode by fusing a cohesin to the catalytic module enables formation of divalent enzyme complexes with dockerin-bearing enzymes. The resultant pseudo-cellulosomes, containing Cel6B combined with endoglucanase Cel5A, exhibits enhanced enzymatic activity, compared to mixtures of wild-type enzymes or bifunctional enzymes, unlike similar pseudo-cellulosomes containing endoglucanase Cel6A or proccessive endoglucanase Cel9A. Insight into the different enzymatic paradigms benefits ongoing development of efficient cellulolytic systems for conversion of plant-derived biomass into valuable sugars. NOVELTY STATEMENT The protein engineering of the modular arrangement of a key exoglucanase from a highly cellulolytic bacterium, Thermobifida fusca, served to explore and compare three major enzymatic paradigms for cellulose degradation. This approach revealed highly active chimaeric forms of the exoglucanase that act in synergy together with a potent endoglucanase in bifunctional enzymes or divalent pseudo-cellulosome-like complexes. Such engineered enzymes could be further integrated into larger enzymatic complexes, thereby providing a significant step forward towards conversion of the entire T. fusca free cellulolytic system into the cellulosomal modex and the enhanced conversion of cellulosic biomass into soluble sugars.
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Affiliation(s)
- Eva Setter-Lamed
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Johanna Stern
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Raphael Lamed
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Ramat Aviv, Israel
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
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Szczupak A, Aizik D, Moraïs S, Vazana Y, Barak Y, Bayer EA, Alfonta L. The Electrosome: A Surface-Displayed Enzymatic Cascade in a Biofuel Cell's Anode and a High-Density Surface-Displayed Biocathodic Enzyme. NANOMATERIALS (BASEL, SWITZERLAND) 2017; 7:E153. [PMID: 28644390 PMCID: PMC5535219 DOI: 10.3390/nano7070153] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 06/12/2017] [Accepted: 06/20/2017] [Indexed: 11/29/2022]
Abstract
The limitation of surface-display systems in biofuel cells to a single redox enzyme is a major drawback of hybrid biofuel cells, resulting in a low copy-number of enzymes per yeast cell and a limitation in displaying enzymatic cascades. Here we present the electrosome, a novel surface-display system based on the specific interaction between the cellulosomal scaffoldin protein and a cascade of redox enzymes that allows multiple electron-release by fuel oxidation. The electrosome is composed of two compartments: (i) a hybrid anode, which consists of dockerin-containing enzymes attached specifically to cohesin sites in the scaffoldin to assemble an ethanol oxidation cascade, and (ii) a hybrid cathode, which consists of a dockerin-containing oxygen-reducing enzyme attached in multiple copies to the cohesin-bearing scaffoldin. Each of the two compartments was designed, displayed, and tested separately. The new hybrid cell compartments displayed enhanced performance over traditional biofuel cells; in the anode, the cascade of ethanol oxidation demonstrated higher performance than a cell with just a single enzyme. In the cathode, a higher copy number per yeast cell of the oxygen-reducing enzyme copper oxidase has reduced the effect of competitive inhibition resulting from yeast oxygen consumption. This work paves the way for the assembly of more complex cascades using different enzymes and larger scaffoldins to further improve the performance of hybrid cells.
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Affiliation(s)
- Alon Szczupak
- Department of Life Sciences and the Ilse Katz Institute for Nanoscale Science and Technology, P.O. Box 653, 8410501 Beer-Sheva, Israel.
| | - Dror Aizik
- Department of Life Sciences and the Ilse Katz Institute for Nanoscale Science and Technology, P.O. Box 653, 8410501 Beer-Sheva, Israel.
| | - Sarah Moraïs
- Department of Biomolecular Sciences, Weizmann Institute of Science, 234 Herzl St., P.O. Box 26, 7610001 Rehovot, Israel.
| | - Yael Vazana
- Department of Biomolecular Sciences, Weizmann Institute of Science, 234 Herzl St., P.O. Box 26, 7610001 Rehovot, Israel.
| | - Yoav Barak
- Department of Chemical Research Support, Weizmann Institute of Science, 234 Herzl St., P.O. Box 26, 7610001 Rehovot, Israel.
| | - Edward A Bayer
- Department of Biomolecular Sciences, Weizmann Institute of Science, 234 Herzl St., P.O. Box 26, 7610001 Rehovot, Israel.
| | - Lital Alfonta
- Department of Life Sciences and the Ilse Katz Institute for Nanoscale Science and Technology, P.O. Box 653, 8410501 Beer-Sheva, Israel.
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Continually emerging mechanistic complexity of the multi-enzyme cellulosome complex. Curr Opin Struct Biol 2017; 44:151-160. [DOI: 10.1016/j.sbi.2017.03.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 03/16/2017] [Accepted: 03/17/2017] [Indexed: 12/20/2022]
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Artzi L, Bayer EA, Moraïs S. Cellulosomes: bacterial nanomachines for dismantling plant polysaccharides. Nat Rev Microbiol 2017; 15:83-95. [PMID: 27941816 DOI: 10.1038/nrmicro.2016.164] [Citation(s) in RCA: 223] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cellulosomes are multienzyme complexes that are produced by anaerobic cellulolytic bacteria for the degradation of lignocellulosic biomass. They comprise a complex of scaffoldin, which is the structural subunit, and various enzymatic subunits. The intersubunit interactions in these multienzyme complexes are mediated by cohesin and dockerin modules. Cellulosome-producing bacteria have been isolated from a large variety of environments, which reflects their prevalence and the importance of this microbial enzymatic strategy. In a given species, cellulosomes exhibit intrinsic heterogeneity, and between species there is a broad diversity in the composition and configuration of cellulosomes. With the development of modern technologies, such as genomics and proteomics, the full protein content of cellulosomes and their expression levels can now be assessed and the regulatory mechanisms identified. Owing to their highly efficient organization and hydrolytic activity, cellulosomes hold immense potential for application in the degradation of biomass and are the focus of much effort to engineer an ideal microorganism for the conversion of lignocellulose to valuable products, such as biofuels.
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Affiliation(s)
- Lior Artzi
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 234 Herzl Street, Rehovot 7610001, Israel
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 234 Herzl Street, Rehovot 7610001, Israel
| | - Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 234 Herzl Street, Rehovot 7610001, Israel
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Bayer EA. Cellulosomes and designer cellulosomes: why toy with Nature? ENVIRONMENTAL MICROBIOLOGY REPORTS 2017; 9:14-15. [PMID: 27756116 DOI: 10.1111/1758-2229.12489] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, 76100, Israel
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Stern J, Artzi L, Moraïs S, Fontes CMGA, Bayer EA. Carbohydrate Depolymerization by Intricate Cellulosomal Systems. Methods Mol Biol 2017; 1588:93-116. [PMID: 28417363 DOI: 10.1007/978-1-4939-6899-2_8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Cellulosomes are multi-enzymatic nanomachines that have been fine-tuned through evolution to efficiently deconstruct plant biomass. Integration of cellulosomal components occurs via highly ordered protein-protein interactions between the various enzyme-borne dockerin modules and the multiple copies of the cohesin modules located on the scaffoldin subunit. Recently, designer cellulosome technology has been established to provide insights into the architectural role of catalytic (enzymatic) and structural (scaffoldin) cellulosomal constituents for the efficient degradation of plant cell wall polysaccharides. Owing to advances in genomics and proteomics, highly structured cellulosome complexes have recently been unraveled, and the information gained has inspired the development of designer cellulosome technology to new levels of complex organization. These higher-order designer cellulosomes have in turn fostered our capacity to enhance the catalytic potential of artificial cellulolytic complexes. In this chapter, methods to produce and employ such intricate cellulosomal complexes are reported.
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Affiliation(s)
- Johanna Stern
- Faculty of Biochemistry, Department of Biomolecular Sciences, The Weizmann Institute of Science, Ullmann Building of Life Sciences, Room 226, Rehovot, 76100, Israel
| | - Lior Artzi
- Faculty of Biochemistry, Department of Biomolecular Sciences, The Weizmann Institute of Science, Ullmann Building of Life Sciences, Room 226, Rehovot, 76100, Israel
| | - Sarah Moraïs
- Faculty of Biochemistry, Department of Biomolecular Sciences, The Weizmann Institute of Science, Ullmann Building of Life Sciences, Room 226, Rehovot, 76100, Israel
| | - Carlos M G A Fontes
- CIISA - Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477, Lisbon, Portugal
| | - Edward A Bayer
- Faculty of Biochemistry, Department of Biomolecular Sciences, The Weizmann Institute of Science, Ullmann Building of Life Sciences, Room 226, Rehovot, 76100, Israel.
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Hyeon JE, Shin SK, Han SO. Design of nanoscale enzyme complexes based on various scaffolding materials for biomass conversion and immobilization. Biotechnol J 2016; 11:1386-1396. [PMID: 27783468 PMCID: PMC5132044 DOI: 10.1002/biot.201600039] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 09/26/2016] [Accepted: 10/07/2016] [Indexed: 12/14/2022]
Abstract
The utilization of scaffolds for enzyme immobilization involves advanced bionanotechnology applications in biorefinery fields, which can be achieved by optimizing the function of various enzymes. This review presents various current scaffolding techniques based on proteins, microbes and nanomaterials for enzyme immobilization, as well as the impact of these techniques on the biorefinery of lignocellulosic materials. Among them, architectural scaffolds have applied to useful strategies for protein engineering to improve the performance of immobilized enzymes in several industrial and research fields. In complexed enzyme systems that have critical roles in carbon metabolism, scaffolding proteins assemble different proteins in relatively durable configurations and facilitate collaborative protein interactions and functions. Additionally, a microbial strain, combined with designer enzyme complexes, can be applied to the immobilizing scaffold because the in vivo immobilizing technique has several benefits in enzymatic reaction systems related to both synthetic biology and metabolic engineering. Furthermore, with the advent of nanotechnology, nanomaterials possessing ideal physicochemical characteristics, such as mass transfer resistance, specific surface area and efficient enzyme loading, can be applied as novel and interesting scaffolds for enzyme immobilization. Intelligent application of various scaffolds to couple with nanoscale engineering tools and metabolic engineering technology may offer particular benefits in research.
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Affiliation(s)
- Jeong Eun Hyeon
- Department of BiotechnologyKorea University02841SeoulRepublic of Korea
| | - Sang Kyu Shin
- Department of BiotechnologyKorea University02841SeoulRepublic of Korea
| | - Sung Ok Han
- Department of BiotechnologyKorea University02841SeoulRepublic of Korea
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Davidi L, Moraïs S, Artzi L, Knop D, Hadar Y, Arfi Y, Bayer EA. Toward combined delignification and saccharification of wheat straw by a laccase-containing designer cellulosome. Proc Natl Acad Sci U S A 2016; 113:10854-9. [PMID: 27621442 PMCID: PMC5047212 DOI: 10.1073/pnas.1608012113] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Efficient breakdown of lignocellulose polymers into simple molecules is a key technological bottleneck limiting the production of plant-derived biofuels and chemicals. In nature, plant biomass degradation is achieved by the action of a wide range of microbial enzymes. In aerobic microorganisms, these enzymes are secreted as discrete elements in contrast to certain anaerobic bacteria, where they are assembled into large multienzyme complexes termed cellulosomes. These complexes allow for very efficient hydrolysis of cellulose and hemicellulose due to the spatial proximity of synergistically acting enzymes and to the limited diffusion of the enzymes and their products. Recently, designer cellulosomes have been developed to incorporate foreign enzymatic activities in cellulosomes so as to enhance lignocellulose hydrolysis further. In this study, we complemented a cellulosome active on cellulose and hemicellulose by addition of an enzyme active on lignin. To do so, we designed a dockerin-fused variant of a recently characterized laccase from the aerobic bacterium Thermobifida fusca The resultant chimera exhibited activity levels similar to the wild-type enzyme and properly integrated into the designer cellulosome. The resulting complex yielded a twofold increase in the amount of reducing sugars released from wheat straw compared with the same system lacking the laccase. The unorthodox use of aerobic enzymes in designer cellulosome machinery effects simultaneous degradation of the three major components of the plant cell wall (cellulose, hemicellulose, and lignin), paving the way for more efficient lignocellulose conversion into soluble sugars en route to alternative fuels production.
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Affiliation(s)
- Lital Davidi
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Lior Artzi
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Doriv Knop
- Faculty of Agricultural, Food, and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Yitzhak Hadar
- Faculty of Agricultural, Food, and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Yonathan Arfi
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel;
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Moraïs S, Stern J, Kahn A, Galanopoulou AP, Yoav S, Shamshoum M, Smith MA, Hatzinikolaou DG, Arnold FH, Bayer EA. Enhancement of cellulosome-mediated deconstruction of cellulose by improving enzyme thermostability. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:164. [PMID: 27493686 PMCID: PMC4973527 DOI: 10.1186/s13068-016-0577-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 07/27/2016] [Indexed: 05/25/2023]
Abstract
BACKGROUND The concerted action of three complementary cellulases from Clostridium thermocellum, engineered to be stable at elevated temperatures, was examined on a cellulosic substrate and compared to that of the wild-type enzymes. Exoglucanase Cel48S and endoglucanase Cel8A, both key elements of the natural cellulosome from this bacterium, were engineered previously for increased thermostability, either by SCHEMA, a structure-guided, site-directed protein recombination method, or by consensus-guided mutagenesis combined with random mutagenesis using error-prone PCR, respectively. A thermostable β-glucosidase BglA mutant was also selected from a library generated by error-prone PCR that will assist the two cellulases in their methodic deconstruction of crystalline cellulose. The effects of a thermostable scaffoldin versus those of a largely mesophilic scaffoldin were also examined. By improving the stability of the enzyme subunits and the structural component, we aimed to improve cellulosome-mediated deconstruction of cellulosic substrates. RESULTS The results demonstrate that the combination of thermostable enzymes as free enzymes and a thermostable scaffoldin was more active on the cellulosic substrate than the wild-type enzymes. Significantly, "thermostable" designer cellulosomes exhibited a 1.7-fold enhancement in cellulose degradation compared to the action of conventional designer cellulosomes that contain the respective wild-type enzymes. For designer cellulosome formats, the use of the thermostabilized scaffoldin proved critical for enhanced enzymatic performance under conditions of high temperatures. CONCLUSIONS Simple improvement in the activity of a given enzyme does not guarantee its suitability for use in an enzyme cocktail or as a designer cellulosome component. The true merit of improvement resides in its ultimate contribution to synergistic action, which can only be determined experimentally. The relevance of the mutated thermostable enzymes employed in this study as components in multienzyme systems has thus been confirmed using designer cellulosome technology. Enzyme integration via a thermostable scaffoldin is critical to the ultimate stability of the complex at higher temperatures. Engineering of thermostable cellulases and additional lignocellulosic enzymes may prove a determinant parameter for development of state-of-the-art designer cellulosomes for their employment in the conversion of cellulosic biomass to soluble sugars.Graphical abstractConversion of conventional designer cellulosomes into thermophilic designer cellulosomes.
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Affiliation(s)
- Sarah Moraïs
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Johanna Stern
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Amaranta Kahn
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Anastasia P. Galanopoulou
- Microbiology Group, Faculty of Biology, National and Kapodistrian University of Athens, Zografou Campus, 15784 Athens, Greece
| | - Shahar Yoav
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
- Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, P.O. Box 12, 76100 Rehovot, Israel
| | - Melina Shamshoum
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Matthew A. Smith
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Dimitris G. Hatzinikolaou
- Microbiology Group, Faculty of Biology, National and Kapodistrian University of Athens, Zografou Campus, 15784 Athens, Greece
| | - Frances H. Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Edward A. Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 76100 Rehovot, Israel
- Department of Biological Chemistry, The Weizmann Institute of Science, 76100 Rehovot, Israel
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