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Potkule JB, Kahar SP, Kumar M, Annapure US. Impact of non-thermal techniques on enzyme modifications for their applications in food. Int J Biol Macromol 2024; 275:133566. [PMID: 38960264 DOI: 10.1016/j.ijbiomac.2024.133566] [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: 06/05/2024] [Accepted: 06/28/2024] [Indexed: 07/05/2024]
Abstract
The present review elaborates on the details of the enzyme, its structure, specificity, and the mechanism of action of selected enzymes as well as structural changes and loss or gain of activity after non-thermal treatments for food-based applications. Enzymes are biological catalysts found in various systems such as plants, animals, and microorganisms. Most of the enzymes have their optimum pH, temperature, and substrate or group of substrates. The conformational modification of enzymes either increases or decreases the rate of reaction at different pH, and temperature conditions. Enzymes are modified by different techniques to enhance the activity of enzymes for their commercial applications mainly due to the high cost of enzymes, stability, and difficulties that occur during the use of enzymes in different conditions. On the opposite, enzyme inactivation provides its application to extend the shelf life of fruits and vegetables by denaturation and partial inactivation of enzymes. Hence, the activation and inactivation of enzymes are studied by non-thermal techniques in both the model and the food system. The highly reactive species generated during non-thermal techniques cause chemical and structural modification. The enzyme modifications depend on the type and source of the enzyme, type of technique, and the parameters used.
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Affiliation(s)
- Jayashree B Potkule
- Department of Food Engineering and Technology, Institute of Chemical Technology, Matunga, Mumbai, India
| | - Suraj P Kahar
- Department of Food Engineering and Technology, Institute of Chemical Technology, Matunga, Mumbai, India
| | - Manoj Kumar
- Chemical and Biochemical Processing Division, ICAR - Central Institute for Research on Cotton Technology, Matunga, Mumbai, India
| | - Uday S Annapure
- Department of Food Engineering and Technology, Institute of Chemical Technology, Matunga, Mumbai, India; Institute of Chemical Technology, Marathwada Campus, Jalna, India.
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2
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de Araújo EA, Cortez AA, Pellegrini VDOA, Vacilotto MM, Cruz AF, Batista PR, Polikarpov I. Molecular mechanism of cellulose depolymerization by the two-domain BlCel9A enzyme from the glycoside hydrolase family 9. Carbohydr Polym 2024; 329:121739. [PMID: 38286536 DOI: 10.1016/j.carbpol.2023.121739] [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: 07/21/2023] [Revised: 12/20/2023] [Accepted: 12/23/2023] [Indexed: 01/31/2024]
Abstract
Carbohydrate-active enzymes from the glycoside hydrolase family 9 (GH9) play a key role in processing lignocellulosic biomass. Although the structural features of some GH9 enzymes are known, the molecular mechanisms that drive their interactions with cellulosic substrates remain unclear. To investigate the molecular mechanisms that the two-domain Bacillus licheniformis BlCel9A enzyme utilizes to depolymerize cellulosic substrates, we used a combination of biochemical assays, X-ray crystallography, small-angle X-ray scattering, and molecular dynamics simulations. The results reveal that BlCel9A breaks down cellulosic substrates, releasing cellobiose and glucose as the major products, but is highly inefficient in cleaving oligosaccharides shorter than cellotetraose. In addition, fungal lytic polysaccharide oxygenase (LPMO) TtLPMO9H enhances depolymerization of crystalline cellulose by BlCel9A, while exhibiting minimal impact on amorphous cellulose. The crystal structures of BlCel9A in both apo form and bound to cellotriose and cellohexaose were elucidated, unveiling the interactions of BlCel9A with the ligands and their contribution to substrate binding and products release. MD simulation analysis reveals that BlCel9A exhibits higher interdomain flexibility under acidic conditions, and SAXS experiments indicate that the enzyme flexibility is induced by pH and/or temperature. Our findings provide new insights into BlCel9A substrate specificity and binding, and synergy with the LPMOs.
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Affiliation(s)
- Evandro Ares de Araújo
- Brazilian Synchrotron Light Laboratory, Brazilian Center for Research in Energy and Materials, Giuseppe Maximo Scolfaro, 10000, Campinas, SP 13083-970, Brazil; Sao Carlos Institute of Physics, University of Sao Paulo, Av. Trabalhador Sao Carlense, 400, Sao Carlos, SP 13566-590, Brazil
| | - Anelyse Abreu Cortez
- Sao Carlos Institute of Physics, University of Sao Paulo, Av. Trabalhador Sao Carlense, 400, Sao Carlos, SP 13566-590, Brazil
| | | | - Milena Moreira Vacilotto
- Sao Carlos Institute of Physics, University of Sao Paulo, Av. Trabalhador Sao Carlense, 400, Sao Carlos, SP 13566-590, Brazil
| | - Amanda Freitas Cruz
- Sao Carlos Institute of Physics, University of Sao Paulo, Av. Trabalhador Sao Carlense, 400, Sao Carlos, SP 13566-590, Brazil
| | - Paulo Ricardo Batista
- Oswaldo Cruz Foundation, Scientific Computing Programme, Av. Brasil, 4365, Rio de Janeiro, RJ 21040-900, Brazil
| | - Igor Polikarpov
- Sao Carlos Institute of Physics, University of Sao Paulo, Av. Trabalhador Sao Carlense, 400, Sao Carlos, SP 13566-590, Brazil.
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3
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Kuch NJ, Kutschke ME, Parker A, Bingman CA, Fox BG. Contribution of calcium ligands in substrate binding and product release in the Acetovibrio thermocellus glycoside hydrolase family 9 cellulase CelR. J Biol Chem 2023; 299:104655. [PMID: 36990218 PMCID: PMC10149213 DOI: 10.1016/j.jbc.2023.104655] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 03/16/2023] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
Enzymatic deconstruction of lignocellulosic biomass is crucial to establishment of the renewable biofuel and bioproduct economy. Better understanding of these enzymes, including their catalytic and binding domains, and other features offer potential avenues for improvement. Glycoside hydrolase family 9 (GH9) enzymes are attractive targets because they have members that exhibit exo- and endo-cellulolytic activity, processivity of reaction, and thermostability. This study examines a GH9 from Acetovibrio thermocellus ATCC 27405, AtCelR containing a catalytic domain and a carbohydrate binding module (CBM3c). Crystal structures of the enzyme without substrate, bound to cellohexaose (substrate) or cellobiose (product), show the positioning of ligands to calcium and adjacent residues in the catalytic domain that may contribute to substrate binding and facilitate product release. We also investigated the properties of the enzyme engineered to contain an additional carbohydrate binding module (CBM3a). Relative to the catalytic domain alone, CBM3a gave improved binding for Avicel (a crystalline form of cellulose), and catalytic efficiency (kcat/KM) was improved 40× with both CBM3c and CBM3a present. However, because of the molecular weight added by CBM3a, the specific activity of the engineered enzyme was not increased relative to the native construct consisting of only the catalytic and CBM3c domains. This work provides new insight into a potential role of the conserved calcium in the catalytic domain and identifies contributions and limitations of domain engineering for AtCelR and perhaps other GH9 enzymes.
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Affiliation(s)
- Nathaniel J Kuch
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Mark E Kutschke
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Alex Parker
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA; Dane County Youth Apprenticeship Program, Dane County School Consortium, Monona, Wisconsin, USA
| | - Craig A Bingman
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA; Collaborative Crystallography Core, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Brian G Fox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA.
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4
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Liu X, Lyu L, Li J, Sen B, Bai M, Stajich JE, Collier JL, Wang G. Comparative Genomic Analyses of Cellulolytic Machinery Reveal Two Nutritional Strategies of Marine Labyrinthulomycetes Protists. Microbiol Spectr 2023; 11:e0424722. [PMID: 36744882 PMCID: PMC10101102 DOI: 10.1128/spectrum.04247-22] [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: 10/18/2022] [Accepted: 01/11/2023] [Indexed: 02/07/2023] Open
Abstract
Labyrinthulomycetes are a group of ubiquitous and diverse unicellular Stramenopiles and have long been known for their vital role in ocean carbon cycling. However, their ecological function from the perspective of organic matter degradation remains poorly understood. This study reports high-quality genomes of two newly isolated Labyrinthulomycetes strains, namely, Botryochytrium sp. strain S-28 and Oblongichytrium sp. strain S-429, and provides molecular analysis of their ecological functions using comparative genomics and a biochemical assay. Our results suggest that Labyrinthulomycetes may occupy multiple ecological niches in marine ecosystems because of the significant differences in gene function among different genera. Certain strains could degrade wheat bran independently by secreting cellulase. The key glycoside hydrolase families (GH1, GH5, and GH9) related to cellulase and the functional domains of carbohydrate-active enzymes (CAZymes) were more enriched in their genomes. This group can actively participate in marine biochemical cycles as decomposers. In contrast, other strains that could not produce cellulase may thrive as "leftover scavengers" and act as a source of nutrients to the higher-trophic-level plankton. In addition, our findings emphasize the dual roles of endoglucanase, acting as both exo- and endoglucanases, in the process of cellulose degradation. Using genomic, biochemical, and phylogenetic analyses, our study provides a broader insight into the nutritional patterns and ecological functions of Labyrinthulomycetes. IMPORTANCE Unicellular heterotrophic eukaryotes are an important component of marine ecosystems. However, their ecological functions and modes of nutrition remain largely unknown. Our current understanding of marine microbial ecology is incomplete without integrating these heterotrophic microeukaryotes into the food web models. This study focuses on the unicellular fungus-like protists Labyrinthulomycetes and provides two high-quality genomes of cellulase-producing Labyrinthulomycetes. Our study uncovers the basis of their cellulase production by deciphering the results of genomic, biochemical, and phylogenetic analyses. This study instigates a further investigation of the molecular mechanism of organic matter utilization by Labyrinthulomycetes in the world's oceans.
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Affiliation(s)
- Xiuping Liu
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Lu Lyu
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Jiaqian Li
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Biswarup Sen
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Mohan Bai
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Jason E. Stajich
- Department of Plant Pathology and Microbiology, University of California, Riverside, California, USA
| | - Jackie L. Collier
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York, USA
| | - Guangyi Wang
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
- Frontiers Science Center for Synthetic Biology, Tianjin University, Tianjin, China
- Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, China
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin, China
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Carbonaro M, Aulitto M, Gallo G, Contursi P, Limauro D, Fiorentino G. Insight into CAZymes of Alicyclobacillus mali FL18: Characterization of a New Multifunctional GH9 Enzyme. Int J Mol Sci 2022; 24:ijms24010243. [PMID: 36613686 PMCID: PMC9820247 DOI: 10.3390/ijms24010243] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022] Open
Abstract
In the bio-based era, cellulolytic and hemicellulolytic enzymes are biocatalysts used in many industrial processes, playing a key role in the conversion of recalcitrant lignocellulosic waste biomasses. In this context, many thermophilic microorganisms are considered as convenient sources of carbohydrate-active enzymes (CAZymes). In this work, a functional genomic annotation of Alicyclobacillus mali FL18, a recently discovered thermo-acidophilic microorganism, showed a wide reservoir of putative CAZymes. Among them, a novel enzyme belonging to the family 9 of glycosyl hydrolases (GHs), named AmCel9, was identified; in-depth in silico analyses highlighted that AmCel9 shares general features with other GH9 members. The synthetic gene was expressed in Escherichia coli and the recombinant protein was purified and characterized. The monomeric enzyme has an optimal catalytic activity at pH 6.0 and has comparable activity at temperatures ranging from 40 °C to 70 °C. It also has a broad substrate specificity, a typical behavior of multifunctional cellulases; the best activity is displayed on β-1,4 linked glucans. Very interestingly, AmCel9 also hydrolyses filter paper and microcrystalline cellulose. This work gives new insights into the properties of a new thermophilic multifunctional GH9 enzyme, that looks a promising biocatalyst for the deconstruction of lignocellulose.
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Affiliation(s)
- Miriam Carbonaro
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy
| | - Martina Aulitto
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Giovanni Gallo
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy
| | - Patrizia Contursi
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy
| | - Danila Limauro
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy
| | - Gabriella Fiorentino
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy
- Correspondence:
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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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7
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Multifunctionality and mechanism of processivity of family GH5 endoglucanase, RfGH5_4 from Ruminococcus flavefaciens on lignocellulosic polymers. Int J Biol Macromol 2022; 224:1395-1411. [DOI: 10.1016/j.ijbiomac.2022.10.227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/15/2022] [Accepted: 10/24/2022] [Indexed: 11/05/2022]
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A processive GH9 family endoglucanase of Bacillus licheniformis and the role of its carbohydrate-binding domain. Appl Microbiol Biotechnol 2022; 106:6059-6075. [PMID: 35948851 DOI: 10.1007/s00253-022-12117-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 07/23/2022] [Accepted: 07/27/2022] [Indexed: 11/02/2022]
Abstract
One of the critical steps in lignocellulosic deconstruction is the hydrolysis of crystalline cellulose by cellulases. Endoglucanases initially facilitate the breakdown of cellulose in lignocellulosic biomass and are further aided by other cellulases to produce fermentable sugars. Furthermore, if the endoglucanase is processive, it can adsorb to the smooth surface of crystalline cellulose and release soluble sugars during repeated cycles of catalysis before dissociating. Most glycoside hydrolase family 9 (GH9) endoglucanases have catalytic domains linked to a CBM (carbohydrate-binding module) (mostly CBM3) and present the second-largest cellulase family after GH5. GH9 endoglucanases are relatively less characterized. Bacillus licheniformis is a mesophilic soil bacterium containing many glycoside hydrolase (GH) enzymes. We identified an endoglucanase gene, gh9A, encoding the GH9 family enzyme H1AD14 in B. licheniformis and cloned and overexpressed H1AD14 in Escherichia coli. The purified H1AD14 exhibited very high enzymatic activity on endoglucanase substrates, such as β-glucan, lichenan, Avicel, CMC-Na (sodium carboxymethyl cellulose) and PASC (phosphoric acid swollen cellulose), across a wide pH range. The enzyme is tolerant to 2 M sodium chloride and retains 74% specific activity on CMC after 10 days, the highest amongst the reported GH9 endoglucanases. The full-length H1AD14 is a processive endoglucanase and efficiently saccharified sugarcane bagasse. The deletion of the CBM reduces the catalytic activity and processivity. The results add to the sparse knowledge of GH9 endoglucanases and offer the possibility of characterizing and engineering additional enzymes from B. licheniformis toward developing a cellulase cocktail for improved biomass deconstruction. KEY POINTS: • H1AD14 is a highly active and processive GH9 endoglucanase from B. licheniformis. • H1AD14 is thermostable and has a very long half-life. • H1AD14 showed higher saccharification efficiency than commercial endoglucanase.
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9
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Ye TJ, Huang KF, Ko TP, Wu SH. Synergic action of an inserted carbohydrate-binding module in a glycoside hydrolase family 5 endoglucanase. Acta Crystallogr D Struct Biol 2022; 78:633-646. [PMID: 35503211 PMCID: PMC9063844 DOI: 10.1107/s2059798322002601] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/07/2022] [Indexed: 11/24/2022] Open
Abstract
A unique endoglucanase with a carbohydrate-binding module inserted in the middle of the catalytic domain has been characterized structurally and functionally, providing insights into the mode of action responsible for its enhanced catalytic performance. Most known cellulase-associated carbohydrate-binding modules (CBMs) are attached to the N- or C-terminus of the enzyme or are expressed separately and assembled into multi-enzyme complexes (for example to form cellulosomes), rather than being an insertion into the catalytic domain. Here, by solving the crystal structure, it is shown that MtGlu5 from Meiothermus taiwanensis WR-220, a GH5-family endo-β-1,4-glucanase (EC 3.2.1.4), has a bipartite architecture consisting of a Cel5A-like catalytic domain with a (β/α)8 TIM-barrel fold and an inserted CBM29-like noncatalytic domain with a β-jelly-roll fold. Deletion of the CBM significantly reduced the catalytic efficiency of MtGlu5, as determined by isothermal titration calorimetry using inactive mutants of full-length and CBM-deleted MtGlu5 proteins. Conversely, insertion of the CBM from MtGlu5 into TmCel5A from Thermotoga maritima greatly enhanced the substrate affinity of TmCel5A. Bound sugars observed between two tryptophan side chains in the catalytic domains of active full-length and CBM-deleted MtGlu5 suggest an important stacking force. The synergistic action of the catalytic domain and CBM of MtGlu5 in binding to single-chain polysaccharides was visualized by substrate modeling, in which additional surface tryptophan residues were identified in a cross-domain groove. Subsequent site-specific mutagenesis results confirmed the pivotal role of several other tryptophan residues from both domains of MtGlu5 in substrate binding. These findings reveal a way to incorporate a CBM into the catalytic domain of an existing enzyme to make a robust cellulase.
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Araújo EA, Dias AHS, Kadowaki MAS, Piyadov V, Pellegrini VOA, Urio MB, Ramos LP, Skaf MS, Polikarpov I. Impact of cellulose properties on enzymatic degradation by bacterial GH48 enzymes: Structural and mechanistic insights from processive Bacillus licheniformis Cel48B cellulase. Carbohydr Polym 2021; 264:118059. [PMID: 33910709 DOI: 10.1016/j.carbpol.2021.118059] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 04/02/2021] [Accepted: 04/05/2021] [Indexed: 11/29/2022]
Abstract
Processive cellulases are highly efficient molecular engines involved in the cellulose breakdown process. However, the mechanism that processive bacterial enzymes utilize to recruit and retain cellulose strands in the catalytic site remains poorly understood. Here, integrated enzymatic assays, protein crystallography and computational approaches were combined to study the enzymatic properties of the processive BlCel48B cellulase from Bacillus licheniformis. Hydrolytic efficiency, substrate binding affinity, cleavage patterns, and the apparent processivity of bacterial BlCel48B are significantly impacted by the cellulose size and its surface morphology. BlCel48B crystallographic structure was solved with ligands spanning -5 to -2 and +1 to +2 subsites. Statistical coupling analysis and molecular dynamics show that co-evolved residues on active site are critical for stabilizing ligands in the catalytic tunnel. Our results provide mechanistic insights into BlCel48B molecular-level determinants of activity, substrate binding, and processivity on insoluble cellulose, thus shedding light on structure-activity correlations of GH48 family members in general.
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Affiliation(s)
- Evandro A Araújo
- São Carlos Institute of Physics, University of São Paulo (USP), São Carlos 13560-970, São Paulo, Brazil; Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials, Campinas 13083-970, São Paulo, Brazil
| | - Artur Hermano Sampaio Dias
- Institute of Chemistry and Center for Computer in Engineering and Sciences, University of Campinas (UNICAMP), Campinas 13084-862, São Paulo, Brazil
| | - Marco A S Kadowaki
- São Carlos Institute of Physics, University of São Paulo (USP), São Carlos 13560-970, São Paulo, Brazil
| | - Vasily Piyadov
- São Carlos Institute of Physics, University of São Paulo (USP), São Carlos 13560-970, São Paulo, Brazil
| | - Vanessa O A Pellegrini
- São Carlos Institute of Physics, University of São Paulo (USP), São Carlos 13560-970, São Paulo, Brazil
| | - Mateus B Urio
- Graduate Programs in Bioenergy, Chemistry and Chemical Engineering, Federal University of Paraná (UFPR), Curitiba 81531-980, Paraná, Brazil
| | - Luiz P Ramos
- Graduate Programs in Bioenergy, Chemistry and Chemical Engineering, Federal University of Paraná (UFPR), Curitiba 81531-980, Paraná, Brazil
| | - Munir S Skaf
- Institute of Chemistry and Center for Computer in Engineering and Sciences, University of Campinas (UNICAMP), Campinas 13084-862, São Paulo, Brazil
| | - Igor Polikarpov
- São Carlos Institute of Physics, University of São Paulo (USP), São Carlos 13560-970, São Paulo, Brazil.
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11
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Coulther TA, Ko J, Ondrechen MJ. Amino acid interactions that facilitate enzyme catalysis. J Chem Phys 2021; 154:195101. [PMID: 34240918 DOI: 10.1063/5.0041156] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Interactions in enzymes between catalytic and neighboring amino acids and how these interactions facilitate catalysis are examined. In examples from both natural and designed enzymes, it is shown that increases in catalytic rates may be achieved through elongation of the buffer range of the catalytic residues; such perturbations in the protonation equilibria are, in turn, achieved through enhanced coupling of the protonation equilibria of the active ionizable residues with those of other ionizable residues. The strongest coupling between protonation states for a pair of residues that deprotonate to form an anion (or a pair that accept a proton to form a cation) is achieved when the difference in the intrinsic pKas of the two residues is approximately within 1 pH unit. Thus, catalytic aspartates and glutamates are often coupled to nearby acidic residues. For an anion-forming residue coupled to a cation-forming residue, the elongated buffer range is achieved when the intrinsic pKa of the anion-forming residue is higher than the intrinsic pKa of the (conjugate acid of the) cation-forming residue. Therefore, the high pKa, anion-forming residues tyrosine and cysteine make good coupling partners for catalytic lysine residues. For the anion-cation pairs, the optimum difference in intrinsic pKas is a function of the energy of interaction between the residues. For the energy of interaction ε expressed in units of (ln 10)RT, the optimum difference in intrinsic pKas is within ∼1 pH unit of ε.
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Affiliation(s)
- Timothy A Coulther
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, USA
| | - Jaeju Ko
- Department of Chemistry, Indiana University of Pennsylvania, Indiana, Pennsylvania 15705, USA
| | - Mary Jo Ondrechen
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, USA
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12
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Laitakari A, Liu L, Frimurer TM, Holst B. The Zinc-Sensing Receptor GPR39 in Physiology and as a Pharmacological Target. Int J Mol Sci 2021; 22:ijms22083872. [PMID: 33918078 PMCID: PMC8070507 DOI: 10.3390/ijms22083872] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 03/31/2021] [Accepted: 04/06/2021] [Indexed: 12/16/2022] Open
Abstract
The G-protein coupled receptor GPR39 is abundantly expressed in various tissues and can be activated by changes in extracellular Zn2+ in physiological concentrations. Previously, genetically modified rodent models have been able to shed some light on the physiological functions of GPR39, and more recently the utilization of novel synthetic agonists has led to the unraveling of several new functions in the variety of tissues GPR39 is expressed. Indeed, GPR39 seems to be involved in many important metabolic and endocrine functions, but also to play a part in inflammation, cardiovascular diseases, saliva secretion, bone formation, male fertility, addictive and depression disorders and cancer. These new discoveries offer opportunities for the development of novel therapeutic approaches against many diseases where efficient therapeutics are still lacking. This review focuses on Zn2+ as an endogenous ligand as well as on the novel synthetic agonists of GPR39, placing special emphasis on the recently discovered physiological functions and discusses their pharmacological potential.
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Affiliation(s)
- Anna Laitakari
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark; (A.L.); (L.L.); (T.M.F.)
| | - Lingzhi Liu
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark; (A.L.); (L.L.); (T.M.F.)
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Thomas M. Frimurer
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark; (A.L.); (L.L.); (T.M.F.)
| | - Birgitte Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark; (A.L.); (L.L.); (T.M.F.)
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
- Correspondence:
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13
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Hershko Rimon A, Livnah O, Rozman Grinberg I, Ortiz de Ora L, Yaniv O, Lamed R, Bayer EA, Frolow F, Voronov-Goldman M. Novel clostridial cell-surface hemicellulose-binding CBM3 proteins. Acta Crystallogr F Struct Biol Commun 2021; 77:95-104. [PMID: 33830074 PMCID: PMC8034430 DOI: 10.1107/s2053230x21002764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 03/15/2021] [Indexed: 11/10/2022] Open
Abstract
A novel member of the family 3 carbohydrate-binding modules (CBM3s) is encoded by a gene (Cthe_0271) in Clostridium thermocellum which is the most highly expressed gene in the bacterium during its growth on several types of biomass substrates. Surprisingly, CtCBM3-0271 binds to at least two different types of xylan, instead of the common binding of CBM3s to cellulosic substrates. CtCBM3-0271 was crystallized and its three-dimensional structure was solved and refined to a resolution of 1.8 Å. In order to learn more about the role of this type of CBM3, a comparative study with its orthologue from Clostridium clariflavum (encoded by the Clocl_1192 gene) was performed, and the three-dimensional structure of CcCBM3-1192 was determined to 1.6 Å resolution. Carbohydrate binding by CcCBM3-1192 was found to be similar to that by CtCBM3-0271; both exhibited binding to xylan rather than to cellulose. Comparative structural analysis of the two CBM3s provided a clear functional correlation of structure and binding, in which the two CBM3s lack the required number of binding residues in their cellulose-binding strips and thus lack cellulose-binding capabilities. This is an enigma, as CtCBM3-0271 was reported to be a highly expressed protein when the bacterium was grown on cellulose. An additional unexpected finding was that CcCBM3-1192 does not contain the calcium ion that was considered to play a structural stabilizing role in the CBM3 family. Despite the lack of calcium, the five residues that form the calcium-binding site are conserved. The absence of calcium results in conformational changes in two loops of the CcCBM3-1192 structure. In this context, superposition of the non-calcium-binding CcCBM3-1192 with CtCBM3-0271 and other calcium-binding CBM3s reveals a much broader two-loop region in the former compared with CtCBM3-0271.
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Affiliation(s)
- Almog Hershko Rimon
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
- The Daniella Rich Institute for Structural Biology Research, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Oded Livnah
- The Wolfson Center for Applied and Structural Biology, Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Inna Rozman Grinberg
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
- The Daniella Rich Institute for Structural Biology Research, Tel Aviv University, Ramat Aviv 69978, Israel
- Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Lizett Ortiz de Ora
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Oren Yaniv
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Raphael Lamed
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
- The Daniella Rich Institute for Structural Biology Research, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Edward A. Bayer
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 760001, Israel
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 8499000, Israel
| | - Felix Frolow
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
- The Daniella Rich Institute for Structural Biology Research, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Milana Voronov-Goldman
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
- The Daniella Rich Institute for Structural Biology Research, Tel Aviv University, Ramat Aviv 69978, Israel
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14
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Zheng Y, Maruoka M, Nanatani K, Hidaka M, Abe N, Kaneko J, Sakai Y, Abe K, Yokota A, Yabe S. High cellulolytic potential of the Ktedonobacteria lineage revealed by genome-wide analysis of CAZymes. J Biosci Bioeng 2021; 131:622-630. [PMID: 33676867 DOI: 10.1016/j.jbiosc.2021.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/10/2021] [Accepted: 01/27/2021] [Indexed: 12/16/2022]
Abstract
Traditionally, filamentous fungi and actinomycetes are well-known cellulolytic microorganisms that have been utilized in the commercial production of cellulase enzyme cocktails for industrial-scale degradation of plant biomass. Noticeably, the Ktedonobacteria lineage (phylum Chloroflexi) with actinomycetes-like morphology was identified and exhibited diverse carbohydrate utilization or degradation abilities. In this study, we performed genome-wide profiling of carbohydrate-active enzymes (CAZymes) in the filamentous Ktedonobacteria lineage. Numerous CAZymes (153-290 CAZymes, representing 63-131 glycoside hydrolases (GHs) per genome), including complex mixtures of endo- and exo-cellulases, were predicted in 15 available Ktedonobacteria genomes. Of note, 4-28 CAZymes were predicted to be extracellular enzymes, whereas 3-29 CAZymes were appended with carbohydrate-binding modules (CBMs) that may promote their binding to insoluble carbohydrate substrates. This number far exceeded other Chloroflexi lineages and were comparable to the cellulolytic actinomycetes. Six multi-modular extracellular GHs were cloned from the thermophilic Thermosporothrix hazakensis SK20-1T strain and heterologously expressed. The putative endo-glucanases of ThazG5-1, ThazG9, and ThazG12 exhibited strong cellulolytic activity, whereas the putative exo-glucanases ThazG6 and ThazG48 formed weak but observable halos on carboxymethyl cellulose plates, indicating their potential biotechnological application. The purified recombinant ThazG12 had near-neutral pH (optimal 6.0), high thermostability (60°C), and broad specificity against soluble and insoluble polysaccharide substrates. It also represented described a novel thermostable bacterial β-1,4-glucanase in the GH12 family. Together, this research revealed the underestimated cellulolytic potential of the Ktedonobacteria lineage and highlighted its potential biotechnological utility as a promising microbial resource for the discovery of industrially useful cellulases.
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Affiliation(s)
- Yu Zheng
- Department of Microbial Resources, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan; Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Mayumi Maruoka
- Department of Microbial Resources, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan; Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Kei Nanatani
- Department of Microbial Resources, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Masafumi Hidaka
- Department of Molecular and Cell Biology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Naoki Abe
- Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Jun Kaneko
- Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Yasuteru Sakai
- Department of Microbial Resources, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan; Hazaka Plant Research Center, Kennan Eisei Kogyo Co., Ltd., 44 Aza Inariyama, Oaza Ashitate, Murata-cho, Shibata-gun, Miyagi 989-1311, Japan
| | - Keietsu Abe
- Department of Microbial Resources, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan; Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Akira Yokota
- Department of Microbial Resources, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan; Hazaka Plant Research Center, Kennan Eisei Kogyo Co., Ltd., 44 Aza Inariyama, Oaza Ashitate, Murata-cho, Shibata-gun, Miyagi 989-1311, Japan
| | - Shuhei Yabe
- Department of Microbial Resources, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8572, Japan; Hazaka Plant Research Center, Kennan Eisei Kogyo Co., Ltd., 44 Aza Inariyama, Oaza Ashitate, Murata-cho, Shibata-gun, Miyagi 989-1311, Japan.
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15
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Aymé L, Hébert A, Henrissat B, Lombard V, Franche N, Perret S, Jourdier E, Heiss-Blanquet S. Characterization of three bacterial glycoside hydrolase family 9 endoglucanases with different modular architectures isolated from a compost metagenome. Biochim Biophys Acta Gen Subj 2021; 1865:129848. [PMID: 33460770 DOI: 10.1016/j.bbagen.2021.129848] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 01/11/2021] [Accepted: 01/11/2021] [Indexed: 10/22/2022]
Abstract
BACKGROUND Environmental bacteria express a wide diversity of glycoside hydrolases (GH). Screening and characterization of GH from metagenomic sources provides an insight into biomass degradation strategies of non-cultivated prokaryotes. METHODS In the present report, we screened a compost metagenome for lignocellulolytic activities and identified six genes encoding enzymes belonging to family GH9 (GH9a-f). Three of these enzymes (GH9b, GH9d and GH9e) were successfully expressed and characterized. RESULTS A phylogenetic analysis of the catalytic domain of pro- and eukaryotic GH9 enzymes suggested the existence of two major subgroups. Bacterial GH9s displayed a wide variety of modular architectures and those harboring an N-terminal Ig-like domain, such as GH9b and GH9d, segregated from the remainder. We purified and characterized GH9 endoglucanases from both subgroups and examined their stabilities, substrate specificities and product profiles. GH9e exhibited an original hydrolysis pattern, liberating an elevated proportion of oligosaccharides longer than cellobiose. All of the enzymes exhibited processive behavior and a synergistic action on crystalline cellulose. Synergy was also evidenced between GH9d and a GH48 enzyme identified from the same metagenome. CONCLUSIONS The characterized GH9 enzymes displayed different modular architectures and distinct substrate and product profiles. The presence of a cellulose binding domain was shown to be necessary for binding and digestion of insoluble cellulosic substrates, but not for processivity. GENERAL SIGNIFICANCE The identification of six GH9 enzymes from a compost metagenome and the functional variety of three characterized members highlight the importance of this enzyme family in bacterial biomass deconstruction.
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Affiliation(s)
- Laure Aymé
- IFP Energies Nouvelles, 1 - 4 avenue du Bois-Préau, 92852 Rueil-Malmaison, France
| | - Agnès Hébert
- IFP Energies Nouvelles, 1 - 4 avenue du Bois-Préau, 92852 Rueil-Malmaison, France
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques (AFMB), CNRS, 163 avenue de Luminy, 13288 Aix Marseille Université, Marseille, France; INRAE, USC1408 Architecture et Fonction des Macromolécules Biologiques (AFMB), 163 avenue de Luminy, 13288 Marseille, France; Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Vincent Lombard
- Architecture et Fonction des Macromolécules Biologiques (AFMB), CNRS, 163 avenue de Luminy, 13288 Aix Marseille Université, Marseille, France; INRAE, USC1408 Architecture et Fonction des Macromolécules Biologiques (AFMB), 163 avenue de Luminy, 13288 Marseille, France
| | - Nathalie Franche
- Aix Marseille Université, CNRS, LCB, 31 Chemin Joseph Aiguier, 13009 Marseille, France
| | - Stéphanie Perret
- Aix Marseille Université, CNRS, LCB, 31 Chemin Joseph Aiguier, 13009 Marseille, France
| | - Etienne Jourdier
- IFP Energies Nouvelles, 1 - 4 avenue du Bois-Préau, 92852 Rueil-Malmaison, France
| | - Senta Heiss-Blanquet
- IFP Energies Nouvelles, 1 - 4 avenue du Bois-Préau, 92852 Rueil-Malmaison, France.
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16
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New thermostable endoglucanase from Spirochaeta thermophila and its mutants with altered substrate preferences. Appl Microbiol Biotechnol 2021; 105:1133-1145. [PMID: 33427929 DOI: 10.1007/s00253-020-11077-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 11/30/2020] [Accepted: 12/27/2020] [Indexed: 10/22/2022]
Abstract
Endoglucanases are key elements in several industrial applications, such as cellulosic biomass hydrolysis, cellulose fiber modification for the production paper and composite materials, and in nanocellulose production. In all of these applications, the desired function of the endoglucanase is to create nicks in the amorphous regions of the cellulose. However, endoglucanase can be diverted from its activity on the fibers by other substrates-soluble oligosaccharides. This issue was addressed in the current study using enzyme engineering and an enzyme evolution approach. To this end, a hypothetical endoglucanase from a thermostable bacterium Spirochaeta thermophila was for the first time cloned and characterized. The wild-type enzyme was used as a starting point for mutagenesis and molecular evolution toward a preference for the higher molecular weight substrates. The best of the evolved enzymes was more active than the wild-type enzyme toward high molecular weight substrate at temperatures below 45 °C (3-fold more active at 30 °C) and showed little or no activity with low molecular weight substrates. These findings can be instrumental in bioeconomy sectors, such as second-generation biofuels and biomaterials from lignocellulosic biomass. KEY POINTS: • A new thermostable endoglucanase was characterized. • The substrate specificity of this endoglucanase was changed by means of genetic engineering. • A mutant with a preference for long molecular weight substrate was obtained and proposed to be beneficial for cellulose fiber modification.
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17
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Tamura K, Dejean G, Van Petegem F, Brumer H. Distinct protein architectures mediate species-specific beta-glucan binding and metabolism in the human gut microbiota. J Biol Chem 2021; 296:100415. [PMID: 33587952 PMCID: PMC7974029 DOI: 10.1016/j.jbc.2021.100415] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/02/2021] [Accepted: 02/10/2021] [Indexed: 12/12/2022] Open
Abstract
Complex glycans that evade our digestive system are major nutrients that feed the human gut microbiota (HGM). The prevalence of Bacteroidetes in the HGM of populations worldwide is engendered by the evolution of polysaccharide utilization loci (PULs), which encode concerted protein systems to utilize the myriad complex glycans in our diets. Despite their crucial roles in glycan recognition and transport, cell-surface glycan-binding proteins (SGBPs) remained understudied cogs in the PUL machinery. Here, we report the structural and biochemical characterization of a suite of SGBP-A and SGBP-B structures from three syntenic β(1,3)-glucan utilization loci (1,3GULs) from Bacteroides thetaiotaomicron (Bt), Bacteroides uniformis (Bu), and B. fluxus (Bf), which have varying specificities for distinct β-glucans. Ligand complexes provide definitive insight into β(1,3)-glucan selectivity in the HGM, including structural features enabling dual β(1,3)-glucan/mixed-linkage β(1,3)/β(1,4)-glucan-binding capability in some orthologs. The tertiary structural conservation of SusD-like SGBPs-A is juxtaposed with the diverse architectures and binding modes of the SGBPs-B. Specifically, the structures of the trimodular BtSGBP-B and BuSGBP-B revealed a tandem repeat of carbohydrate-binding module-like domains connected by long linkers. In contrast, BfSGBP-B comprises a bimodular architecture with a distinct β-barrel domain at the C terminus that bears a shallow binding canyon. The molecular insights obtained here contribute to our fundamental understanding of HGM function, which in turn may inform tailored microbial intervention therapies.
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Affiliation(s)
- Kazune Tamura
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada; Department of Biochemistry and Molecular Biology, The Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Guillaume Dejean
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology, The Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Harry Brumer
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada; Department of Biochemistry and Molecular Biology, The Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada; Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada.
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18
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Lv K, Shao W, Pedroso MM, Peng J, Wu B, Li J, He B, Schenk G. Enhancing the catalytic activity of a GH5 processive endoglucanase from Bacillus subtilis BS-5 by site-directed mutagenesis. Int J Biol Macromol 2020; 168:442-452. [PMID: 33310097 DOI: 10.1016/j.ijbiomac.2020.12.060] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 11/16/2022]
Abstract
Processive endoglucanases possess both endo- and exoglucanase activity, making them attractive discovery and engineering targets. Here, a processive endoglucanase EG5C-1 from Bacillus subtilis was employed as the starting point for enzyme engineering. Referring to the complex structure information of EG5C-1 and cellohexaose, the amino acid residues in the active site architecture were identified and subjected to alanine scanning mutagenesis. The residues were chosen for a saturation mutagenesis since their variants showed similar activities to EG5C-1. Variants D70Q and S235W showed increased activity towards the substrates CMC and Avicel, an increase was further enhanced in D70Q/S235W double mutant, which displayed a 2.1- and 1.7-fold improvement in the hydrolytic activity towards CMC and Avicel, respectively. In addition, kinetic measurements showed that double mutant had higher substrate affinity (Km) and a significantly higher catalytic efficiency (kcat/Km). The binding isotherms of wild-type EG5C-1 and double mutant D70Q/S235W suggested that the binding capability of EG5C-1 for the insoluble substrate was weaker than that of D70Q/S235W. Molecular dynamics simulations suggested that the collaborative substitutions of D70Q and S235W altered the hydrogen bonding network within the active site architecture and introduced new hydrogen bonds between the enzyme and cellohexaose, thus enhancing both substrate affinity and catalytic efficiency.
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Affiliation(s)
- Kemin Lv
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhunan road, Nanjing 211816, Jiangsu, China
| | - Wenyu Shao
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhunan road, Nanjing 211816, Jiangsu, China
| | - Marcelo Monteiro Pedroso
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Jiayu Peng
- School of Pharmaceutical Sciences, Nanjing Tech University, 30 Puzhunan road, Nanjing 211816, Jiangsu, China
| | - Bin Wu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhunan road, Nanjing 211816, Jiangsu, China.
| | - Jiahuang Li
- School of Life Science, Nanjing University, Nanjing 210023, Jiangsu, China.
| | - Bingfang He
- School of Pharmaceutical Sciences, Nanjing Tech University, 30 Puzhunan road, Nanjing 211816, Jiangsu, China
| | - Gerhard Schenk
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
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19
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Kumar K, Singh S, Sharma K, Goyal A. Computational modeling and small-angle X-ray scattering based structure analysis and identifying ligand cleavage mechanism by processive endocellulase of family 9 glycoside hydrolase (HtGH9) from Hungateiclostridium thermocellum ATCC 27405. J Mol Graph Model 2020; 103:107808. [PMID: 33248343 DOI: 10.1016/j.jmgm.2020.107808] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/13/2020] [Accepted: 11/13/2020] [Indexed: 11/16/2022]
Abstract
The cellulases of family 9 glycoside hydrolase with subtle difference in amino acid sequence have shown different types of catalytic activities such as endo-, exo- or processive endocellulase. However, the reason behind the different types of catalytic activities still unclear. In this study, the processive endocellulase, HtGH9 of family 9 GH from Hungateiclostridium thermocellum was modeled by homology modeling. The catalytic module (HtGH9t) of HtGH9 modeled structure displayed the (α/α)6 barrel topology and associated family 3 carbohydrate binding module (HtCBM3c) displayed β-sandwich fold. Ramachandran plot of HtGH9 modeled structure displayed all the amino acid residues in allowed region except Asn225 and Asp317. Secondary structure analysis of modeled HtGH9 showed the presence of 41.3% α-helices and 11.0% β-strands which was validated through circular dichroism analysis that showed the presence of 42.6% α-helices and 14.5% β-strands. Molecular Dynamic (MD) simulation of HtGH9 structure for 50 ns showed Root Mean Square Deviation (RMSD), 0.84 nm and radius of gyration (Rg) 3.1 nm. The Small-angle X-ray scattering of HtGH9 confirmed the monodisperse state. The radius of gyration for globular shape (Rg) was 5.50 ± 0.15 nm and for rod shape (Rc) by Guinier plot was 2.0 nm. The loop formed by amino acid residues, 264-276 towards one end of the catalytic site of HtGH9 forms a barrier, that blocks the non-reducing end of the cellulose chain causing the processive cleavage resulting in the release of cellotetraose. The position of the corresponding loop in cellulases of family 9 GH is responsible for different types of cleavage patterns.
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Affiliation(s)
- Krishan Kumar
- Carbohydrate Enzyme Biotechnology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Shubha Singh
- Division of Biological Sciences and Engineering, Netaji Subhas University of Technology, Delhi, 110078, India
| | - Kedar Sharma
- Carbohydrate Enzyme Biotechnology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India; Laboratory of Small Molecules & Macro Molecular Crystallography, Department of Bioengineering, Indian Institute of Technology Gandhinagar, Gandhinagar, 382355, India
| | - Arun Goyal
- Carbohydrate Enzyme Biotechnology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
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20
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Abstract
Some cellulases exhibit “processivity”: the ability to degrade crystalline cellulose through successive hydrolytic catalytic reactions without the release of the enzyme from the substrate surface. We previously observed the movement of fungal processive cellulases by high-speed atomic force microscopy, and here, we use the same technique to directly observe the processive movement of bacterial cellobiohydrolases settling a long-standing controversy. Although fungal and bacterial processive cellulases have completely different protein folds, they have evolved to acquire processivity through the same strategy of adding subsites to extend the substrate-binding site and forming a tunnel-like active site by increasing the number of loops covering the active site. This represents an example of protein-level convergent evolution to acquire the same functions from different ancestors. Cellulose is the most abundant biomass on Earth, and many microorganisms depend on it as a source of energy. It consists mainly of crystalline and amorphous regions, and natural degradation of the crystalline part is highly dependent on the degree of processivity of the degrading enzymes (i.e., the extent of continuous hydrolysis without detachment from the substrate cellulose). Here, we report high-speed atomic force microscopic (HS-AFM) observations of the movement of four types of cellulases derived from the cellulolytic bacteria Cellulomonas fimi on various insoluble cellulose substrates. The HS-AFM images clearly demonstrated that two of them (CfCel6B and CfCel48A) slide on crystalline cellulose. The direction of processive movement of CfCel6B is from the nonreducing to the reducing end of the substrate, which is opposite that of processive cellulase Cel7A of the fungus Trichoderma reesei (TrCel7A), whose movement was first observed by this technique, while CfCel48A moves in the same direction as TrCel7A. When CfCel6B and TrCel7A were mixed on the same substrate, “traffic accidents” were observed, in which the two cellulases blocked each other’s progress. The processivity of CfCel6B was similar to those of fungal family 7 cellulases but considerably higher than those of fungal family 6 cellulases. The results indicate that bacteria utilize family 6 cellulases as high-processivity enzymes for efficient degradation of crystalline cellulose, whereas family 7 enzymes have the same function in fungi. This is consistent with the idea of convergent evolution of processive cellulases in fungi and bacteria to achieve similar functionality using different protein foldings.
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21
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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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Li F, Dong J, Lv X, Wen Y, Chen S. Recombinant expression and characterization of two glycoside hydrolases from extreme alklinphilic bacterium Cellulomonas bogoriensis 69B4 T. AMB Express 2020; 10:44. [PMID: 32157462 PMCID: PMC7064699 DOI: 10.1186/s13568-020-00979-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 02/26/2020] [Indexed: 01/05/2023] Open
Abstract
Two novel glycoside hydrolases were cloned from the genomic DNA of alklinphilic bacterium Cellulomonas bogoriensis 69B4T and functionally expressed in Escherichia coli. The two enzymes shared less than 73% of identities with other known glycosidases and belonged to glycoside hydrolase families 5 and 9. Recombinant Cel5A exhibited optimum activity at pH 5.0 and at a temperature of 70 °C, and Cel9A showed optimum activity at pH 7.0 and at a temperature of 60 °C. The two enzymes exhibited activity at alkaline pH 11 and were stable over a wide range of pH. The maximum activities of Cel5A and Cel9A were observed in 0.5 M NaCl and 1 M KCl, respectively. In addition, these two enzymes exhibited excellent halostability with residual activities of more than 70% after pre-incubation for 6 days in 5 M NaCl or 4 M KCl. Substrate specificity analysis revealed that Cel5A and Cel9A specifically cleaved the β-1,4-glycosidic linkage in cellulose with the highest activity on carboxymethyl cellulose sodium (78.3 and 145.3 U/mg, respectively). Cel5A is an endoglucanase, whereas Cel9A exhibits endo and exo activities. As alkali-activated, thermo-tolerant, and salt-tolerant cellulases, Cel5A and Cel9A are promising candidates for further research and industrial applications.
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Sørlie M, Horn SJ, Vaaje-Kolstad G, Eijsink VG. Using chitosan to understand chitinases and the role of processivity in the degradation of recalcitrant polysaccharides. REACT FUNCT POLYM 2020. [DOI: 10.1016/j.reactfunctpolym.2020.104488] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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24
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A novel multifunctional GH9 enzyme from Paenibacillus curdlanolyticus B-6 exhibiting endo/exo functions of cellulase, mannanase and xylanase activities. Appl Microbiol Biotechnol 2020; 104:2079-2096. [DOI: 10.1007/s00253-020-10388-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 01/07/2020] [Accepted: 01/16/2020] [Indexed: 12/13/2022]
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25
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Wang Y, Zhou Y, Shi S, Lu G, Lin X, Xie C, Liu D, Yao D. A rational design for improving the pepsin resistance of cellulase E4 isolated from T. fusca based on the evaluation of the transition complex and molecular structure. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2019.107417] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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26
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Simultaneous Enhancement of Thermostability and Catalytic Activity of a Metagenome-Derived β-Glucosidase Using Directed Evolution for the Biosynthesis of Butyl Glucoside. Int J Mol Sci 2019; 20:ijms20246224. [PMID: 31835569 PMCID: PMC6940790 DOI: 10.3390/ijms20246224] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/08/2019] [Accepted: 12/08/2019] [Indexed: 01/16/2023] Open
Abstract
Butyl glucoside synthesis using bioenzymatic methods at high temperatures has gained increasing interest. Protein engineering using directed evolution of a metagenome-derived β-glucosidase of Bgl1D was performed to identify enzymes with improved activity and thermostability. An interesting mutant Bgl1D187 protein containing five amino acid substitutions (S28T, Y37H, D44E, R91G, and L115N), showed catalytic efficiency (kcat/Km of 561.72 mM−1 s−1) toward ρ-nitrophenyl-β-d-glucopyranoside (ρNPG) that increased by 23-fold, half-life of inactivation by 10-fold, and further retained transglycosidation activity at 50 °C as compared with the wild-type Bgl1D protein. Site-directed mutagenesis also revealed that Asp44 residue was essential to β-glucosidase activity of Bgl1D. This study improved our understanding of the key amino acids of the novel β-glucosidases and presented a raw material with enhanced catalytic activity and thermostability for the synthesis of butyl glucosides.
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Gu Y, Zheng F, Wang Y, Su X, Bai Y, Yao B, Huang H, Luo H. Characterization of two thermophilic cellulases from Talaromyces leycettanus JCM12802 and their synergistic action on cellulose hydrolysis. PLoS One 2019; 14:e0224803. [PMID: 31730665 PMCID: PMC6857856 DOI: 10.1371/journal.pone.0224803] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/22/2019] [Indexed: 11/29/2022] Open
Abstract
Talaromyces leycettanus JCM12802 is a great producer of thermophilic glycoside hydrolases (GHs). In this study, two cellulases (TlCel5A and TlCel6A) belonging to GH5 and GH6 respectively were expressed in Pichia pastoris and functionally characterized. The enzymes had acidic and thermophilic properties, showing optimal activities at pH 3.5–4.5 and 75–80°C, and retained stable at temperatures up to 60°C and over a broad pH range of 2.0−8.0. TlCel5A and TlCel6A acted against several cellulose substrates with varied activities (3,101.1 vs. 92.9 U/mg to barley β-glucan, 3,905.6 U/mg vs. 109.0 U/mg to lichenan, and 840.3 and 0.09 U/mg to CMC-Na). When using Avicel, phosphoric acid swollen cellulose (PASC) or steam-exploded corn straw (SECS) as the substrate, combination of TlCel5A and TlCel6A showed significant synergistic action, releasing more reduced sugars (1.08–2.87 mM) than the individual enzymes. These two cellulases may represent potential enzyme additives for the efficient biomass conversion and bioethanol production.
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Affiliation(s)
- Yuan Gu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Fei Zheng
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, People’s Republic of China
| | - Yuan Wang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Yingguo Bai
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Bin Yao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Huoqing Huang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
- * E-mail: (HL); (HH)
| | - Huiying Luo
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
- * E-mail: (HL); (HH)
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Linton SM. Review: The structure and function of cellulase (endo-β-1,4-glucanase) and hemicellulase (β-1,3-glucanase and endo-β-1,4-mannase) enzymes in invertebrates that consume materials ranging from microbes, algae to leaf litter. Comp Biochem Physiol B Biochem Mol Biol 2019; 240:110354. [PMID: 31647988 DOI: 10.1016/j.cbpb.2019.110354] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/04/2019] [Accepted: 09/16/2019] [Indexed: 12/01/2022]
Abstract
This review discusses the reaction catalysed, and the structure and function of the cellulase, endo-β-1,4-glucanase and the hemicellulase enzymes, β-1,3-glucanase and endo-β-1,4-mannase that are present in numerous invertebrate groups with a diverse range of feeding specialisations. These range from microbial deposit and filter feeders, micro and macrophagous algal feeders, omnivores to herbivorous leaf litter and wood feeders. Endo-β-1,4-glucanase from glycosyl hydrolase family 9 (GH9) digests cellulose like β-1,4-glucans from a range of materials. As it hydrolyses crystalline cellulose very slowly, it is a poor cellulase. Where tested, the enzyme has dual endo-β-1,4-glucanase and lichenase activity. Its presence does not necessarily indicate the ability of an animal to digest cellulose. It only indicates the ability to digest β-1,4-glucans and its function, which is discussed in this review, should be considered with reference to the substrates present in the diet. β-1,3-glucanase (laminarinase) belongs to glycosyl hydrolase family 16 (GH16) and hydrolyses β-1.3-glucans. These polysaccharides are present in the cell walls of algae, protozoans and yeast, and they also occur as storage polysaccharides within protozoans and algae. Depending on their site of expression, these enzymes may function as a digestive enzyme or may be involved in innate immunity. Enzymes present in the digestive fluids or tissues, would be digestive. Haemolymph GH16 proteins may be involved in innate immunity through the activation of the phenol oxidase system. Insect GH16 proteins expressed within the haemolymph have lost their catalytic residues and function as β-glucan binding proteins. In contrast, crustacean GH16 proteins expressed within the same tissue, have retained the catalytic residues and thus possibly their β-1,3-glucanase activity. The potential function of which is discussed. Endo-β-1,4-mannase from glycosyl hydrolase family 5, subfamily 10 (GH5_10) hydrolyses mannan, glucomannan and galactomannan. These hemicelluloses are present in the cell walls of plants and algae and also function as storage polysaccharides within legume and palm seeds. They are digestive enzymes whose high expression in some species suggests they are a major contributor to hemicellulose digestion. They may also provide the animal with substantial amounts of monosaccharides for energy.
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Affiliation(s)
- Stuart M Linton
- School of Life and Environmental Sciences, Deakin University, VIC 3216, Australia.
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Tsvetkov VO, Yarullina LG. Structural and Functional Characteristics of Hydrolytic Enzymes of Phytophagon Insects and Plant Protein Inhibitors (Review). APPL BIOCHEM MICRO+ 2019. [DOI: 10.1134/s0003683819050156] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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30
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Stepnov AA, Fredriksen L, Steen IH, Stokke R, Eijsink VGH. Identification and characterization of a hyperthermophilic GH9 cellulase from the Arctic Mid-Ocean Ridge vent field. PLoS One 2019; 14:e0222216. [PMID: 31491027 PMCID: PMC6731012 DOI: 10.1371/journal.pone.0222216] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 08/23/2019] [Indexed: 11/29/2022] Open
Abstract
A novel GH9 cellulase (AMOR_GH9A) was discovered by sequence-based mining of a unique metagenomic dataset collected at the Jan Mayen hydrothermal vent field. AMOR_GH9A comprises a signal peptide, a catalytic domain and a CBM3 cellulose-binding module. AMOR_GH9A is an exceptionally stable enzyme with a temperature optimum around 100°C and an apparent melting temperature of 105°C. The novel cellulase retains 64% of its activity after 4 hours of incubation at 95°C. The closest characterized homolog of AMOR_GH9A is TfCel9A, a processive endocellulase from the model thermophilic bacterium Thermobifida fusca (64.2% sequence identity). Direct comparison of AMOR_GH9A and TfCel9A revealed that AMOR_GH9A possesses higher activity on soluble and amorphous substrates (phosphoric acid swollen cellulose, konjac glucomannan) and has an ability to hydrolyse xylan that is lacking in TfCel9A.
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Affiliation(s)
- Anton A. Stepnov
- Faculty of Chemistry, Biotechnology and Food Science, NMBU—Norwegian University of Life Sciences, Ås, Norway
| | - Lasse Fredriksen
- Faculty of Chemistry, Biotechnology and Food Science, NMBU—Norwegian University of Life Sciences, Ås, Norway
| | - Ida H. Steen
- Department of Biological Sciences and KG Jebsen Centre for Deep Sea Research, University of Bergen, Bergen, Norway
| | - Runar Stokke
- Department of Biological Sciences and KG Jebsen Centre for Deep Sea Research, University of Bergen, Bergen, Norway
| | - Vincent G. H. Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU—Norwegian University of Life Sciences, Ås, Norway
- * E-mail:
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31
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Processivity and the Mechanisms of Processive Endoglucanases. Appl Biochem Biotechnol 2019; 190:448-463. [DOI: 10.1007/s12010-019-03096-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 07/18/2019] [Indexed: 11/26/2022]
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Kundu S. Insights into the mechanism(s) of digestion of crystalline cellulose by plant class C GH9 endoglucanases. J Mol Model 2019; 25:240. [PMID: 31338614 PMCID: PMC7385011 DOI: 10.1007/s00894-019-4133-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 07/11/2019] [Indexed: 02/03/2023]
Abstract
Biofuels such as γ-valerolactone, bioethanol, and biodiesel are derived from potentially fermentable cellulose and vegetable oils. Plant class C GH9 endoglucanases are CBM49-encompassing hydrolases that cleave the β (1 → 4) glycosidic linkage of contiguous D-glucopyranose residues of crystalline cellulose. Here, I analyse 3D-homology models of characterised and putative class C enzymes to glean insights into the contribution of the GH9, linker, and CBM49 to the mechanism(s) of crystalline cellulose digestion. Crystalline cellulose may be accommodated in a surface groove which is imperfectly bounded by the GH9_CBM49, GH9_linker, and linker_CBM49 surfaces and thence digested in a solvent accessible subsurface cavity. The physical dimensions and distortions thereof, of the groove, are mediated in part by the bulky side chains of aromatic amino acids that comprise it and may also result in a strained geometry of the bound cellulose polymer. These data along with an almost complete absence of measurable cavities, along with poorly conserved, hydrophobic, and heterogeneous amino acid composition, increased atomic motion of the CBM49_linker junction, and docking experiements with ligands of lower degrees of polymerization suggests a modulatory rather than direct role for CBM49 in catalysis. Crystalline cellulose is the de facto substrate for CBM-containing plant and non-plant GH9 enzymes, a finding supported by exceptional sequence- and structural-homology. However, despite the implied similarity in general acid-base catalysis of crystalline cellulose, this study also highlights qualitative differences in substrate binding and glycosidic bond cleavage amongst class C members. Results presented may aid the development of novel plant-based GH9 endoglucanases that could extract and utilise potential fermentable carbohydrates from biomass. Crystalline cellulose digestion by plant class C GH9 endoglucanases - an in silico assessment of function. ![]()
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Affiliation(s)
- Siddhartha Kundu
- Department of Biochemistry, Army College of Medical Sciences, Brar Square, Delhi Cantt., New Delhi, 110010, India.
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Herrera LM, Braña V, Franco Fraguas L, Castro-Sowinski S. Characterization of the cellulase-secretome produced by the Antarctic bacterium Flavobacterium sp. AUG42. Microbiol Res 2019; 223-225:13-21. [PMID: 31178046 DOI: 10.1016/j.micres.2019.03.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/28/2019] [Accepted: 03/22/2019] [Indexed: 10/27/2022]
Abstract
Flavobacterium sp. AUG42 is a cellulase-producing bacterium isolated from the Antarctic oligochaete Grania sp. (Annelida). In this work, we report that AUG42 produces a glycoside hydrolase cocktail with CMCase, PASCase and cellobiase activities (optimum pHs and temperatures ranging from 5.5 to 6.5 and 40 to 50 °C, respectively). The time-course analyses of the bacterial growth and cellulase production showed that the cocktail has maximal activity at the stationary phase when growing at 16 °C with filter paper as a cellulosic carbon source, among the tested substrates. The analyses of the CAZome and the identification of secreted proteins by shotgun Mass Spectrometry analysis showed that five glycoside hydrolyses are present in the bacterial secretome, which probably cooperate in the degradation of the cellulosic substrates. Two of these glycoside hydrolyses may harbor putative carbohydrate binding modules, both with a cleft-like active site. The cellulolytic cocktail was assayed in saccharification experiments using carboxymethylcellulose as a substrate and results showed the release of glucose (a fermentable sugar) and other reducing-sugars, after 24 h incubation. The ecological relevance of producing cellulases in the Antarctic environment, as well as their potential use in the bio-refinery industry, are discussed.
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Affiliation(s)
- Lorena M Herrera
- Biochemistry and Molecular Biology, Faculty of Sciences, Universidad de la República (UdelaR), Iguá 4225, 11400, Montevideo, Uruguay
| | - Victoria Braña
- Molecular Microbiology, Institute Clemente Estable, Av. Italia 3318, 11600, Montevideo, Uruguay
| | - Laura Franco Fraguas
- Cátedra de Bioquímica, Departamento de Biociencias, Facultad de Química, Universidad de la República, Av. Gral. Flores 2124, 11800, Montevideo, Uruguay
| | - Susana Castro-Sowinski
- Biochemistry and Molecular Biology, Faculty of Sciences, Universidad de la República (UdelaR), Iguá 4225, 11400, Montevideo, Uruguay; Molecular Microbiology, Institute Clemente Estable, Av. Italia 3318, 11600, Montevideo, Uruguay.
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Cloning, expression, and characterization of novel GH5 endoglucanases from Thermobifida alba AHK119. J Biosci Bioeng 2019; 127:554-562. [DOI: 10.1016/j.jbiosc.2018.10.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 10/13/2018] [Accepted: 10/16/2018] [Indexed: 01/01/2023]
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Hamre AG, Kaupang A, Payne CM, Väljamäe P, Sørlie M. Thermodynamic Signatures of Substrate Binding for Three Thermobifida fusca Cellulases with Different Modes of Action. Biochemistry 2019; 58:1648-1659. [PMID: 30785271 DOI: 10.1021/acs.biochem.9b00014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The enzymatic breakdown of recalcitrant polysaccharides is achieved by synergistic enzyme cocktails of glycoside hydrolases (GHs) and accessory enzymes. Many GHs are processive, meaning that they stay bound to the substrate between subsequent catalytic interactions. Cellulases are GHs that catalyze the hydrolysis of cellulose [β-1,4-linked glucose (Glc)]. Here, we have determined the relative subsite binding affinity for a glucose moiety as well as the thermodynamic signatures for (Glc)6 binding to three of the seven cellulases produced by the bacterium Thermobifida fusca. TfCel48A is exo-processive, TfCel9A endo-processive, and TfCel5A endo-nonprocessive. Initial hydrolysis of (Glc)5 and (Glc)6 was performed in H218O enabling the incorporation of an 18O atom at the new reducing end anomeric carbon. A matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the products reveals the intensity ratios of otherwise identical 18O- and 16O-containing products to provide insight into how the substrate is placed during productive binding. The two processive cellulases have significant binding affinity in subsites where products dissociate during processive hydrolysis, aligned with a need to have a pushing potential to remove obstacles on the substrate. Moreover, we observed a correlation between processive ability and favorable binding free energy, as previously postulated. Upon ligand binding, the largest contribution to the binding free energy is desolvation for all three cellulases as determined by isothermal titration calorimetry. The two endo-active cellulases show a more favorable solvation entropy change compared to the exo-active cellulase, while the two processive cellulases have less favorable changes in binding enthalpy compared to the nonprocessive TfCel5A.
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Affiliation(s)
- Anne Grethe Hamre
- Department of Chemistry, Biotechnology and Food Science , Norwegian University of Life Sciences , P.O. Box 5003, N-1432 Ås , Norway
| | - Anita Kaupang
- Department of Chemistry, Biotechnology and Food Science , Norwegian University of Life Sciences , P.O. Box 5003, N-1432 Ås , Norway
| | - Christina M Payne
- Department of Chemical and Materials Engineering , University of Kentucky , 177 F. Paul Anderson Tower , Lexington , Kentucky 40506 , United States
| | - Priit Väljamäe
- Institute of Molecular and Cell Biology , University of Tartu , 50090 Tartu , Estonia
| | - Morten Sørlie
- Department of Chemistry, Biotechnology and Food Science , Norwegian University of Life Sciences , P.O. Box 5003, N-1432 Ås , Norway
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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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Jeng WY, Liu CI, Lu TJ, Lin HJ, Wang NC, Wang AHJ. Crystal Structures of the C-Terminally Truncated Endoglucanase Cel9Q from Clostridium thermocellum Complexed with Cellodextrins and Tris. Chembiochem 2019; 20:295-307. [PMID: 30609216 DOI: 10.1002/cbic.201800789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Indexed: 11/11/2022]
Abstract
Endoglucanase CtCel9Q is one of the enzyme components of the cellulosome, which is an active cellulase system in the thermophile Clostridium thermocellum. The precursor form of CtCel9Q comprises a signal peptide, a glycoside hydrolase family 9 catalytic domain, a type 3c carbohydrate-binding module (CBM), and a type I dockerin domain. Here, we report the crystal structures of C-terminally truncated CtCel9Q (CtCel9QΔc) complexed with Tris, Tris+cellobiose, cellobiose+cellotriose, cellotriose, and cellotetraose at resolutions of 1.50, 1.70, 2.05, 2.05 and 1.75 Å, respectively. CtCel9QΔc forms a V-shaped homodimer through residues Lys529-Glu542 on the type 3c CBM, which pairs two β-strands (β4 and β5 of the CBM). In addition, a disulfide bond was formed between the two Cys535 residues of the protein monomers in the asymmetric unit. The structures allow the identification of four minus (-) subsites and two plus (+) subsites; this is important for further understanding the structural basis of cellulose binding and hydrolysis. In the oligosaccharide-free and cellobiose-bound CtCel9QΔc structures, a Tris molecule was found to be bound to three catalytic residues of CtCel9Q and occupied subsite -1 of the CtCel9Q active-site cleft. Moreover, the enzyme activity assay in the presence of 100 mm Tris showed that the Tris almost completely suppressed CtCel9Q hydrolase activity.
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Affiliation(s)
- Wen-Yih Jeng
- University Center for Bioscience and Biotechnology, National Cheng Kung University, 1 University Road, Tainan, 701, Taiwan.,Department of Biochemistry and Molecular Biology, National Cheng Kung University, 1 University Road, Tainan, 701, Taiwan
| | - Chia-I Liu
- School of Medical Laboratory Science and Biotechnology, Taipei Medical University, 250 Wuxing Street, Taipei, 110, Taiwan
| | - Te-Jung Lu
- Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology, 89 Wenhua 1st Street, Tainan, 717, Taiwan
| | - Hong-Jie Lin
- University Center for Bioscience and Biotechnology, National Cheng Kung University, 1 University Road, Tainan, 701, Taiwan
| | - Nai-Chen Wang
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Sec. 2, Taipei, 115, Taiwan
| | - Andrew H-J Wang
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Sec 2, Taipei, 115, Taiwan
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38
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de Araújo EA, de Oliveira Neto M, Polikarpov I. Biochemical characterization and low-resolution SAXS structure of two-domain endoglucanase BlCel9 from Bacillus licheniformis. Appl Microbiol Biotechnol 2018; 103:1275-1287. [PMID: 30547217 DOI: 10.1007/s00253-018-9508-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 10/03/2018] [Accepted: 11/07/2018] [Indexed: 12/16/2022]
Abstract
Lignocellulose feedstock constitutes the most abundant carbon source in the biosphere; however, its recalcitrance remains a challenge for microbial conversion into biofuel and bioproducts. Bacillus licheniformis is a microbial mesophilic bacterium capable of secreting a large number of glycoside hydrolase (GH) enzymes, including a glycoside hydrolase from GH family 9 (BlCel9). Here, we conducted biochemical and biophysical studies of recombinant BlCel9, and its low-resolution molecular shape was retrieved from small angle X-ray scattering (SAXS) data. BlCel9 is an endoglucanase exhibiting maximum catalytic efficiency at pH 7.0 and 60 °C. Furthermore, it retains 80% of catalytic activity within a broad range of pH values (5.5-8.5) and temperatures (up to 50 °C) for extended periods of time (over 48 h). It exhibits the highest hydrolytic activity against phosphoric acid swollen cellulose (PASC), followed by bacterial cellulose (BC), filter paper (FP), and to a lesser extent carboxymethylcellulose (CMC). The HPAEC-PAD analysis of the hydrolytic products demonstrated that the end product of the enzymatic hydrolysis is primarily cellobiose, and also small amounts of glucose, cellotriose, and cellotetraose are produced. SAXS data analysis revealed that the enzyme adopts a monomeric state in solution and has a molecular mass of 65.8 kDa as estimated from SAXS data. The BlCel9 has an elongated shape composed of an N-terminal family 3 carbohydrate-binding module (CBM3c) and a C-terminal GH9 catalytic domain joined together by 20 amino acid residue long linker peptides. The domains are closely juxtaposed in an extended conformation and form a relatively rigid structure in solution, indicating that the interactions between the CBM3c and GH9 catalytic domains might play a key role in cooperative cellulose biomass recognition and hydrolysis.
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Affiliation(s)
- Evandro Ares de Araújo
- Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador Saocarlense 400, São Carlos, SP, 13560-970, Brazil
| | - Mário de Oliveira Neto
- Departmento de Física e Biofísica, Universidade Estadual Paulista "Júlio de Mesquita Filho", R. Prof. Dr. Antonio Celso Wagner Zanin 689, Jardim Sao Jose, Botucatu, SP, 18618-970, Brazil
| | - Igor Polikarpov
- Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador Saocarlense 400, São Carlos, SP, 13560-970, Brazil.
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39
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Han F, Liu Y, E J, Guan S, Han W, Shan Y, Wang S, Zhang H. Effects of Tyr555 and Trp678 on the processivity of cellobiohydrolase A from Ruminiclostridium thermocellum: A simulation study. Biopolymers 2018; 109:e23238. [PMID: 30484856 DOI: 10.1002/bip.23238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/21/2018] [Accepted: 10/01/2018] [Indexed: 12/12/2022]
Abstract
Cellobiohydrolase A from Ruminiclostridium thermocellum (Cbh9A) is a processive exoglucanase from family 9 and is an important cellobiohydrolase that hydrolyzes cello-oligosaccharide into cellobiose. Residues Tyr555 and Trp678 considerably affect catalytic activity, but their mechanisms are still unknown. To investigate how the Tyr555 and Trp678 affect the processivity of Cbh9A, conventional molecular dynamics, steered molecular dynamics, and free energy calculation were performed to simulate the processive process of wild type (WT)-Cbh9A, Y555S mutant, and W678G mutant. Analysis of simulation results suggests that the binding free energies between the substrate and WT-Cbh9A are lower than those of Y555S and W678G mutants. The pull forces and energy barrier in Y555S and W678G mutants also reduced significantly during the steered molecular dynamics (SMD) simulation compared with that of the WT-Cbh9A. And the potential mean force calculations showed that the pulling energy barrier of Y555S and W678G mutants is much lower than that of WT-Cbh9A.
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Affiliation(s)
- Fei Han
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China
| | - Ye Liu
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, National Engineering Laboratory of AIDS Vaccine, College of Life Science, Jilin University, Changchun, China
| | - Jingwen E
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China
| | - Shanshan Guan
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, National Engineering Laboratory of AIDS Vaccine, College of Life Science, Jilin University, Changchun, China
| | - Weiwei Han
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, National Engineering Laboratory of AIDS Vaccine, College of Life Science, Jilin University, Changchun, China
| | - Yaming Shan
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, National Engineering Laboratory of AIDS Vaccine, College of Life Science, Jilin University, Changchun, China
| | - Song Wang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China
| | - Hao Zhang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, China
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40
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Lu X, Feng X, Li X, Zhao J. Binding and hydrolysis properties of engineered cellobiohydrolases and endoglucanases. BIORESOURCE TECHNOLOGY 2018; 267:235-241. [PMID: 30025319 DOI: 10.1016/j.biortech.2018.06.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 06/14/2018] [Accepted: 06/17/2018] [Indexed: 05/03/2023]
Abstract
Because cellulase was the main enzyme used in bioconversion of lignocellulose, it was a valid way to reduce the hydrolysis cost by increasing the adsorption and hydrolysis efficiency of cellulase. In this study, modified cellobiohydrolases (CBHs) and endoglucanases (EGs) were constructed. Two engineered cellulases CBH-TrCBMV27E,P30D,Link1 and EG-TrCBMV27E,P30D,Link1 well-performed during hydrolysis. Compared to wild-type enzymes, EG-TrCBMV27E,P30D,Link1 had relatively less adsorption ability to lignin and greater affinity to cellulose, especially Avicel. However, for CBH-TrCBMV27E,P30D,Link1, the hydrolysis manner was changed and in favor to hydrolysis process, although the adsorption properties were unexpected. It suggested that various binding conformations of polysaccharide on CBMs hypothetically resulted in different functions of CBMs, including binding ability, processive and digestive properties on fiber surface. Fusion of T. r-CBMV27E,P30D,Link1 to cellulase, both CBH and EG, gave the destruction ability of enzyme and increased the accessible surface of substrate to cellulase, enhanced the adsorption and hydrolysis efficiency of cellulase.
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Affiliation(s)
- Xianqin Lu
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Xiaoting Feng
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China.
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41
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Tamayo‐Ordóñez MC, Ayil‐Gutiérrez BA, Tamayo‐Ordóñez YJ, Rodríguez‐Zapata LC, Monforte‐González M, De la Cruz‐Arguijo EA, García‐Castillo MJ, Sánchez‐Teyer LF. Review and in silico analysis of fermentation, bioenergy, fiber, and biopolymer genes of biotechnological interest in
Agave
L. for genetic improvement and biocatalysis. Biotechnol Prog 2018; 34:1314-1334. [DOI: 10.1002/btpr.2689] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 06/04/2018] [Accepted: 06/26/2018] [Indexed: 12/17/2022]
Affiliation(s)
- M. C. Tamayo‐Ordóñez
- Unidad de Biotecnología. Centro de Investigación Científica de Yucatán, Calle 43 No. 130, Colonia Chuburná de Hidalgo, CP. 97200, Mérida Yucatán Mexico
| | - B. A. Ayil‐Gutiérrez
- CONACYT‐ Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Blvd. del Maestro, s/n, Esq. Elías Piña Reynosa 88710 Mexico
| | - Y. J. Tamayo‐Ordóñez
- Unidad de Biotecnología. Centro de Investigación Científica de Yucatán, Calle 43 No. 130, Colonia Chuburná de Hidalgo, CP. 97200, Mérida Yucatán Mexico
| | - L. C. Rodríguez‐Zapata
- Unidad de Biotecnología. Centro de Investigación Científica de Yucatán, Calle 43 No. 130, Colonia Chuburná de Hidalgo, CP. 97200, Mérida Yucatán Mexico
| | - M. Monforte‐González
- Unidad de Bioquímica Centro de Investigación Científica de Yucatán, Calle 43 No. 130, Colonia Chuburná de Hidalgo, CP. 97200, Mérida Yucatán Mexico
| | - E. A. De la Cruz‐Arguijo
- Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Blvd. del Maestro, s/n, Esq. Elías Piña Reynosa 88710 Mexico
| | - M. J. García‐Castillo
- Unidad de Biotecnología. Centro de Investigación Científica de Yucatán, Calle 43 No. 130, Colonia Chuburná de Hidalgo, CP. 97200, Mérida Yucatán Mexico
| | - L. F. Sánchez‐Teyer
- Unidad de Biotecnología. Centro de Investigación Científica de Yucatán, Calle 43 No. 130, Colonia Chuburná de Hidalgo, CP. 97200, Mérida Yucatán Mexico
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42
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Fu Y, Yeom SJ, Kwon KK, Hwang J, Kim H, Woo EJ, Lee DH, Lee SG. Structural and functional analyses of the cellulase transcription regulator CelR. FEBS Lett 2018; 592:2776-2785. [PMID: 30062758 DOI: 10.1002/1873-3468.13206] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 07/05/2018] [Accepted: 07/19/2018] [Indexed: 11/10/2022]
Abstract
CelR is a transcriptional regulator that controls the expression of cellulases catalyzing cellulose hydrolysis. However, the structural mechanism of its regulation has remained unclear. Here, we report the first structure of CelR, in this case with cellobiose bound. CelR consists of a DNA-binding domain (DBD) and a regulatory domain (RD), and homodimerizes with each monomer bound to cellobiose. A hinge region (HR) in CelR connects the DBD with the RD, and Leu59 in the HR acts as a 'leucine lever' that transduces a transcriptional activation signal. Furthermore, an α4 helix mediates the ligand-binding signal for transcriptional activation. Tyr84 and Gln301 can potentially alter the ligand specificity of CelR. This study provides a pivotal step toward understanding transcription of the cellulases.
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Affiliation(s)
- Yaoyao Fu
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea.,The Key Laboratory of Biotechnology for Medicinal Plant of Jiangsu Province, Jiangsu Normal University, China
| | - Soo-Jin Yeom
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea
| | - Kil Koang Kwon
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea
| | - Jungwon Hwang
- Infection and Immunity Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea
| | - Haseong Kim
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea.,Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, Korea
| | - Eui-Jeon Woo
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea.,Department of Bio-Analytical Science, KRIBB School of Bioscience, University of Science and Technology (UST), Daejeon, Korea
| | - Dae-Hee Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea.,Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, Korea
| | - Seung-Goo Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea.,Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, Korea
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43
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Wu L, Davies GJ. Structure of the GH9 glucosidase/glucosaminidase from Vibrio cholerae. Acta Crystallogr F Struct Biol Commun 2018; 74:512-523. [PMID: 30084401 PMCID: PMC6096475 DOI: 10.1107/s2053230x18011019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/01/2018] [Indexed: 03/30/2024] Open
Abstract
Glycoside hydrolase family 9 (GH9) of carbohydrate-processing enzymes primarily consists of inverting endoglucanases. A subgroup of GH9 enzymes are believed to act as exo-glucosidases or exo-glucosaminidases, with many being found in organisms of the family Vibrionaceae, where they are proposed to function within the chitin-catabolism pathway. Here, it is shown that the GH9 enzyme from the pathogen Vibrio cholerae (hereafter referred to as VC0615) is active on both chitosan-derived and β-glucoside substrates. The structure of VC0615 at 3.17 Å resolution is reported from a crystal form with poor diffraction and lattice disorder. VC0615 was highly refractory to crystallization efforts, with crystals only appearing using a high protein concentration under conditions containing the precipitant poly-γ-glutamic acid (PGA). The structure is highly mobile within the crystal lattice, which is likely to reflect steric clashes between symmetry molecules which destabilize crystal packing. The overall tertiary structure of VC0615 is well resolved even at 3.17 Å resolution, which has allowed the structural basis for the exo-glucosidase/glucosaminidase activity of this enzyme to be investigated.
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Affiliation(s)
- Liang Wu
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Gideon J. Davies
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
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44
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Ellinghaus TL, Pereira JH, McAndrew RP, Welner DH, DeGiovanni AM, Guenther JM, Tran HM, Feldman T, Simmons BA, Sale KL, Adams PD. Engineering glycoside hydrolase stability by the introduction of zinc binding. Acta Crystallogr D Struct Biol 2018; 74:702-710. [PMID: 29968680 PMCID: PMC6038386 DOI: 10.1107/s2059798318006678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 05/01/2018] [Indexed: 02/04/2023] Open
Abstract
The development of robust enzymes, in particular cellulases, is a key step in the success of biological routes to `second-generation' biofuels. The typical sources of the enzymes used to degrade biomass include mesophilic and thermophilic organisms. The endoglucanase J30 from glycoside hydrolase family 9 was originally identified through metagenomic analyses of compost-derived bacterial consortia. These studies, which were tailored to favor growth on targeted feedstocks, have already been shown to identify cellulases with considerable thermal tolerance. The amino-acid sequence of J30 shows comparably low identity to those of previously analyzed enzymes. As an enzyme that combines a well measurable activity with a relatively low optimal temperature (50°C) and a modest thermal tolerance, it offers the potential for structural optimization aimed at increased stability. Here, the crystal structure of wild-type J30 is presented along with that of a designed triple-mutant variant with improved characteristics for industrial applications. Through the introduction of a structural Zn2+ site, the thermal tolerance was increased by more than 10°C and was paralleled by an increase in the catalytic optimum temperature by more than 5°C.
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Affiliation(s)
- Thomas L. Ellinghaus
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jose H. Pereira
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ryan P. McAndrew
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ditte H. Welner
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Andy M. DeGiovanni
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Joel M. Guenther
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Biological and Engineering Sciences Center, Sandia National Laboratories, Livermore, CA 94551, USA
| | - Huu M. Tran
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Biological and Engineering Sciences Center, Sandia National Laboratories, Livermore, CA 94551, USA
| | - Taya Feldman
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Biological and Engineering Sciences Center, Sandia National Laboratories, Livermore, CA 94551, USA
| | - Blake A. Simmons
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Kenneth L. Sale
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Biological and Engineering Sciences Center, Sandia National Laboratories, Livermore, CA 94551, USA
| | - Paul D. Adams
- Joint BioEnergy Institute, Emeryville, CA 94608, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Bioengineering, University of California, Berkeley, CA 94720, USA
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45
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Guerriero G, Sergeant K, Legay S, Hausman JF, Cauchie HM, Ahmad I, Siddiqui KS. Novel Insights from Comparative In Silico Analysis of Green Microalgal Cellulases. Int J Mol Sci 2018; 19:E1782. [PMID: 29914107 PMCID: PMC6032398 DOI: 10.3390/ijms19061782] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/08/2018] [Accepted: 06/08/2018] [Indexed: 11/24/2022] Open
Abstract
The assumption that cellulose degradation and assimilation can only be carried out by heterotrophic organisms was shattered in 2012 when it was discovered that the unicellular green alga, Chlamydomonas reinhardtii (Cr), can utilize cellulose for growth under CO₂-limiting conditions. Publications of genomes/transcriptomes of the colonial microalgae, Gonium pectorale (Gp) and Volvox carteri (Vc), between 2010⁻2016 prompted us to look for cellulase genes in these algae and to compare them to cellulases from bacteria, fungi, lower/higher plants, and invertebrate metazoans. Interestingly, algal catalytic domains (CDs), belonging to the family GH9, clustered separately and showed the highest (33⁻42%) and lowest (17⁻36%) sequence identity with respect to cellulases from invertebrate metazoans and bacteria, respectively, whereas the identity with cellulases from plants was only 27⁻33%. Based on comparative multiple alignments and homology models, the domain arrangement and active-site architecture of algal cellulases are described in detail. It was found that all algal cellulases are modular, consisting of putative novel cysteine-rich carbohydrate-binding modules (CBMs) and proline/serine-(PS) rich linkers. Two genes were found to encode a protein with a putative Ig-like domain and a cellulase with an unknown domain, respectively. A feature observed in one cellulase homolog from Gp and shared by a spinach cellulase is the existence of two CDs separated by linkers and with a C-terminal CBM. Dockerin and Fn-3-like domains, typically found in bacterial cellulases, are absent in algal enzymes. The targeted gene expression analysis shows that two Gp cellulases consisting, respectively, of a single and two CDs were upregulated upon filter paper addition to the medium.
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Affiliation(s)
- Gea Guerriero
- Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg.
| | - Kjell Sergeant
- Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg.
| | - Sylvain Legay
- Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg.
| | - Jean-Francois Hausman
- Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg.
| | - Henry-Michel Cauchie
- Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg.
| | - Irshad Ahmad
- Life Sciences Department, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.
| | - Khawar Sohail Siddiqui
- Life Sciences Department, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.
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46
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Zhang KD, Li W, Wang YF, Zheng YL, Tan FC, Ma XQ, Yao LS, Bayer EA, Wang LS, Li FL. Processive Degradation of Crystalline Cellulose by a Multimodular Endoglucanase via a Wirewalking Mode. Biomacromolecules 2018; 19:1686-1696. [DOI: 10.1021/acs.biomac.8b00340] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kun-Di Zhang
- Shandong Provincial Key Laboratory of Energy Genetics, Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101 Qingdao, People’s Republic of China
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People’s Republic of China
| | - Wen Li
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People’s Republic of China
| | - Ye-Fei Wang
- Shandong Provincial Key Laboratory of Energy Genetics, Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101 Qingdao, People’s Republic of China
| | - Yan-Lin Zheng
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, 266590, People’s Republic of China
| | - Fang-Cheng Tan
- Shandong Provincial Key Laboratory of Energy Genetics, Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101 Qingdao, People’s Republic of China
| | - Xiao-Qing Ma
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong, 266101, People’s Republic of China
| | - Li-Shan Yao
- Shandong Provincial Key Laboratory of Energy Genetics, Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101 Qingdao, People’s Republic of China
| | - Edward A. Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Lu-Shan Wang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People’s Republic of China
| | - Fu-Li Li
- Shandong Provincial Key Laboratory of Energy Genetics, Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101 Qingdao, People’s Republic of China
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47
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Burgin T, Ståhlberg J, Mayes HB. Advantages of a distant cellulase catalytic base. J Biol Chem 2018; 293:4680-4687. [PMID: 29321205 PMCID: PMC5880141 DOI: 10.1074/jbc.ra117.001186] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/02/2018] [Indexed: 11/06/2022] Open
Abstract
The inverting glycoside hydrolase Trichoderma reesei (Hypocrea jecorina) Cel6A is a promising candidate for protein engineering for more economical production of biofuels. Until recently, its catalytic mechanism had been uncertain: The best candidate residue to serve as a catalytic base, Asp-175, is farther from the glycosidic cleavage site than in other glycoside hydrolase enzymes. Recent unbiased transition path sampling simulations revealed the hydrolytic mechanism for this more distant base, employing a water wire; however, it is not clear why the enzyme employs a more distant catalytic base, a highly conserved feature among homologs across different kingdoms. In this work, we describe molecular dynamics simulations designed to uncover how a base with a longer side chain, as in a D175E mutant, affects procession and active site alignment in the Michaelis complex. We show that the hydrogen bond network is tuned to the shorter aspartate side chain, and that a longer glutamate side chain inhibits procession as well as being less likely to adopt a catalytically productive conformation. Furthermore, we draw comparisons between the active site in Trichoderma reesei Cel6A and another inverting, processive cellulase to deduce the contribution of the water wire to the overall enzyme function, revealing that the more distant catalytic base enhances product release. Our results can inform efforts in the study and design of enzymes by demonstrating how counterintuitive sacrifices in chemical reactivity can have worthwhile benefits for other steps in the catalytic cycle.
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Affiliation(s)
- Tucker Burgin
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan, 48109
| | - Jerry Ståhlberg
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden
| | - Heather B Mayes
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan, 48109.
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48
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Meier KK, Jones SM, Kaper T, Hansson H, Koetsier MJ, Karkehabadi S, Solomon EI, Sandgren M, Kelemen B. Oxygen Activation by Cu LPMOs in Recalcitrant Carbohydrate Polysaccharide Conversion to Monomer Sugars. Chem Rev 2018; 118:2593-2635. [PMID: 29155571 PMCID: PMC5982588 DOI: 10.1021/acs.chemrev.7b00421] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Natural carbohydrate polymers such as starch, cellulose, and chitin provide renewable alternatives to fossil fuels as a source for fuels and materials. As such, there is considerable interest in their conversion for industrial purposes, which is evidenced by the established and emerging markets for products derived from these natural polymers. In many cases, this is achieved via industrial processes that use enzymes to break down carbohydrates to monomer sugars. One of the major challenges facing large-scale industrial applications utilizing natural carbohydrate polymers is rooted in the fact that naturally occurring forms of starch, cellulose, and chitin can have tightly packed organizations of polymer chains with low hydration levels, giving rise to crystalline structures that are highly recalcitrant to enzymatic degradation. The topic of this review is oxidative cleavage of carbohydrate polymers by lytic polysaccharide mono-oxygenases (LPMOs). LPMOs are copper-dependent enzymes (EC 1.14.99.53-56) that, with glycoside hydrolases, participate in the degradation of recalcitrant carbohydrate polymers. Their activity and structural underpinnings provide insights into biological mechanisms of polysaccharide degradation.
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Affiliation(s)
- Katlyn K. Meier
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Stephen M. Jones
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Thijs Kaper
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, California 94304, United States
| | - Henrik Hansson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Martijn J. Koetsier
- DuPont Industrial Biosciences, Netherlands, Nieuwe Kanaal 7-S, 6709 PA Wageningen, The Netherlands
| | - Saeid Karkehabadi
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Edward I. Solomon
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Bradley Kelemen
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, California 94304, United States
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49
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cDNA sequences of GHF9 endo-β-1,4-glucanases in terrestrial Crustacea. Gene 2018; 642:408-422. [DOI: 10.1016/j.gene.2017.11.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 10/25/2017] [Accepted: 11/09/2017] [Indexed: 12/25/2022]
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50
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Costa MGS, Silva YF, Batista PR. Computational engineering of cellulase Cel9A-68 functional motions through mutations in its linker region. Phys Chem Chem Phys 2018; 20:7643-7652. [DOI: 10.1039/c7cp07073j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cellulase collective motions design through linker mutations leads to the enhancement of protein flexibility and function.
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Affiliation(s)
- M. G. S. Costa
- Programa de Computação Científica (PROCC)
- Fundação Oswaldo Cruz
- Rio de Janeiro
- Brazil
| | - Y. F. Silva
- Programa de Computação Científica (PROCC)
- Fundação Oswaldo Cruz
- Rio de Janeiro
- Brazil
| | - P. R. Batista
- Programa de Computação Científica (PROCC)
- Fundação Oswaldo Cruz
- Rio de Janeiro
- Brazil
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