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Nakazawa H, Okada I, Ito T, Ishigaki Y, Kumagai I, Umetsu M. Combinatorial optimization of the hybrid cellulase complex structure designed from modular libraries. Sci Rep 2024; 14:22429. [PMID: 39342015 PMCID: PMC11438973 DOI: 10.1038/s41598-024-73541-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 09/18/2024] [Indexed: 10/01/2024] Open
Abstract
Cellulase selectively recognizes cellulose surfaces and cleaves their β-1,4-glycosidic bonds. Combining hydrolysis using cellulase and fermentation can produce alternative fuels and chemical products. However, anaerobic bacteria produce only low levels of highly active cellulase complexes so-called cellulosomes. Therefore, we designed hybrid cellulase complexes from 49 biotinylated catalytic domain (CD) and 30 biotinylated cellulose-binding domain (CBD) libraries on streptavidin-conjugated nanoparticles to enhance cellulose hydrolysis by mimicking the cellulosome structure. The hybrid cellulase complex, incorporating both native CD and CBD, significantly improved reducing sugar production from cellulose compared to free native modular enzymes. The optimal CBD for each hybrid cellulase complex differed from that of the native enzyme. The most effective hybrid cellulase complex was observed with the combination of CD6-4 from Thermobifida fusca YX and CBD46 from the Bacillus halodurans C-125. The hybrid cellulase complex/CD6-4-CBD46 and -CD6-4-CBD2-5 combinations showed increased reducing sugar production. Similar results were also observed in microcrystalline cellulose degradation. Furthermore, clustering on nanoparticles enhanced enzyme thermostability. Our results demonstrate that hybrid cellulase complex structures improve enzyme function through synergistic effects and extend the lifespan of the enzyme.
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Affiliation(s)
- Hikaru Nakazawa
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-1, Aramaki, Aoba-Ku, Sendai, 980-8579, Japan.
| | - Izumi Okada
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-1, Aramaki, Aoba-Ku, Sendai, 980-8579, Japan
| | - Tomoyuki Ito
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-1, Aramaki, Aoba-Ku, Sendai, 980-8579, Japan
| | - Yuri Ishigaki
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-1, Aramaki, Aoba-Ku, Sendai, 980-8579, Japan
| | - Izumi Kumagai
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-1, Aramaki, Aoba-Ku, Sendai, 980-8579, Japan
| | - Mitsuo Umetsu
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-1, Aramaki, Aoba-Ku, Sendai, 980-8579, Japan.
- Center for Advanced Intelligence Project, RIKEN, Tokyo, Japan.
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2
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Zheng F, Yang J, Luo H, Sun Q, Zhang X, Li R, He X, Zhao G. Hydrolysis Mechanism of Multimodular Endoglucanases with Distinctive Domain Composition in the Saccharification of Cellulosic Substrates. Biomacromolecules 2024; 25:6007-6016. [PMID: 39207087 DOI: 10.1021/acs.biomac.4c00660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Two multimodular endoglucanases in glycoside hydrolase family 5, ReCel5 and ElCel5, share 73% identity and exhibit similar modular structures: family 1 carbohydrate-binding module (CBM1); catalytic domain; CBMX2; module of unknown function. However, they differed in their biochemical properties and catalytic performance. ReCel5 showed optimal activity at pH 4.0 and 70 °C, maintaining stability at 70 °C (>80% activity). Conversely, ElCel5 is optimal at pH 3.0 and 50 °C (>50% activity at 50 °C). ElCel5 excels in degrading CMC-Na (256 U/mg vs 53 U/mg of ReCel5). Five domain-truncated (TM1-TM5) and four domain-replaced (RM1-RM4) mutants of ReCel5 with the counterparts of ElCel5 were constructed, and their enzymatic properties were compared with those of the wild type. Only RM1, with ElCel5-CBM1, displayed enhanced thermostability and activity. The hydrolysis of pretreated corn stover was reduced in most TM and RM mutants. Molecular dynamics simulations revealed interdomain interactions within the multimodular endoglucanase, potentially affecting its structural stability and complex biological catalytic processes.
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Affiliation(s)
- Fei Zheng
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
- Beijing Key Laboratory of Food Processing and Safety in Forestry, Beijing Forestry University, Beijing 100083, China
| | - Junzhao Yang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
- Beijing Key Laboratory of Food Processing and Safety in Forestry, Beijing Forestry University, Beijing 100083, China
| | - Huiying Luo
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Qingyang Sun
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
- Beijing Key Laboratory of Food Processing and Safety in Forestry, Beijing Forestry University, Beijing 100083, China
| | - Xinrui Zhang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
- Beijing Key Laboratory of Food Processing and Safety in Forestry, Beijing Forestry University, Beijing 100083, China
| | - Ruilin Li
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
- Beijing Key Laboratory of Food Processing and Safety in Forestry, Beijing Forestry University, Beijing 100083, China
| | - Xiangwei He
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
- Beijing Key Laboratory of Food Processing and Safety in Forestry, Beijing Forestry University, Beijing 100083, China
| | - Guozhu Zhao
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
- Beijing Key Laboratory of Food Processing and Safety in Forestry, Beijing Forestry University, Beijing 100083, China
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3
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Liu J, Shi J, Gao J, Shi R, Zhu J, Jensen MS, Li C, Yang J, Zhao S, Sun A, Sun D, Zhang Y, Liu C, Liu W. Functional studies on tandem carbohydrate-binding modules of a multimodular enzyme possessing two catalytic domains. Appl Environ Microbiol 2024; 90:e0088824. [PMID: 38940565 PMCID: PMC11267928 DOI: 10.1128/aem.00888-24] [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: 05/10/2024] [Accepted: 06/09/2024] [Indexed: 06/29/2024] Open
Abstract
Although functional studies on carbohydrate-binding module (CBM) have been carried out extensively, the role of tandem CBMs in the enzyme containing multiple catalytic domains (CDs) is unclear. Here, we identified a multidomain enzyme (Lc25986) with a novel modular structure from lignocellulolytic bacterial consortium. It consists of a mannanase domain, two CBM65 domains (LcCBM65-1/LcCBM65-2), and an esterase domain. To investigate CBM function and domain interactions, full-length Lc25986 and its variants were constructed and used for enzymatic activity, binding, and bioinformatic analyses. The results showed that LcCBM65-1 and LcCBM65-2 both bind mannan and xyloglucan but not cellulose or β-1,3-1,4-glucan, which differs from the ligand specificity of reported CBM65s. Compared to LcCBM65-2, LcCBM65-1 showed a stronger ligand affinity and a preference for acetylation sites. Both CBM65s stimulated the enzymatic activities of their respective neighboring CDs against acetylated mannan, but did not contribute to the activities of the distal CDs. The time course of mannan hydrolysis indicated that the full-length Lc25986 was more effective in the complete degradation of mixed acetyl/non-acetyl substrates than the mixture of single-CD mutants. When acting on complex substrates, LcCBM65-1 not only improved the enzymatic activity of the mannanase domain, but also directed the esterase domain to the acetylated polysaccharides. LcCBM65-2 adopted a low affinity to reduce interference with the catalysis of the mannanase domain. These results demonstrate the importance of CBMs for the synergism between the two CDs of a multidomain enzyme and suggest that they contribute to the adequate degradation of complex substrates such as plant cell walls. IMPORTANCE Lignocellulolytic enzymes, particularly those of bacterial origin, often harbor multiple carbohydrate-binding modules (CBMs). However, the function of CBM multivalency remains poorly understood. This is especially true for enzymes that contain more than one catalytic domain (CD), as the interactions between CDs, CBMs, and CDs and CBMs can be complex. Our research demonstrates that homogeneous CBMs can have distinct functions in a multimodular enzyme. The tandem CBMs coordinate the CDs in catalytic conflict through their differences in binding affinity, ligand preference, and arrangement within the full-length enzyme. Additionally, although the synergism between mannanase and esterase is widely acknowledged, our study highlights the benefits of integrating the two enzymes into a single entity for the degradation of complex substrates. In summary, these findings enhance our understanding of the intra-synergism of a multimodular enzyme and emphasize the significance of multiple CBMs in this context.
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Affiliation(s)
- Jiawen Liu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jiani Shi
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jiahui Gao
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Rui Shi
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jingrong Zhu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Marcus Sepo Jensen
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Chenchen Li
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jing Yang
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Siyi Zhao
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Aofei Sun
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Di Sun
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Ying Zhang
- School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Cong Liu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Weijie Liu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
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You Y, Kong H, Li C, Gu Z, Ban X, Li Z. Carbohydrate binding modules: Compact yet potent accessories in the specific substrate binding and performance evolution of carbohydrate-active enzymes. Biotechnol Adv 2024; 73:108365. [PMID: 38677391 DOI: 10.1016/j.biotechadv.2024.108365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 04/17/2024] [Accepted: 04/17/2024] [Indexed: 04/29/2024]
Abstract
Carbohydrate binding modules (CBMs) are independent non-catalytic domains widely found in carbohydrate-active enzymes (CAZymes), and they play an essential role in the substrate binding process of CAZymes by guiding the appended catalytic modules to the target substrates. Owing to their precise recognition and selective affinity for different substrates, CBMs have received increasing research attention over the past few decades. To date, CBMs from different origins have formed a large number of families that show a variety of substrate types, structural features, and ligand recognition mechanisms. Moreover, through the modification of specific sites of CBMs and the fusion of heterologous CBMs with catalytic domains, improved enzymatic properties and catalytic patterns of numerous CAZymes have been achieved. Based on cutting-edge technologies in computational biology, gene editing, and protein engineering, CBMs as auxiliary components have become portable and efficient tools for the evolution and application of CAZymes. With the aim to provide a theoretical reference for the functional research, rational design, and targeted utilization of novel CBMs in the future, we systematically reviewed the function-related characteristics and potentials of CAZyme-derived CBMs in this review, including substrate recognition and binding mechanisms, non-catalytic contributions to enzyme performances, module modifications, and innovative applications in various fields.
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Affiliation(s)
- Yuxian You
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Haocun Kong
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Caiming Li
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Zhengbiao Gu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Xiaofeng Ban
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Zhaofeng Li
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China.
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5
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Shi Q, Abdel-Hamid AM, Sun Z, Cheng Y, Tu T, Cann I, Yao B, Zhu W. Carbohydrate-binding modules facilitate the enzymatic hydrolysis of lignocellulosic biomass: Releasing reducing sugars and dissociative lignin available for producing biofuels and chemicals. Biotechnol Adv 2023; 65:108126. [PMID: 36921877 DOI: 10.1016/j.biotechadv.2023.108126] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/05/2023] [Accepted: 03/08/2023] [Indexed: 03/16/2023]
Abstract
The microbial decomposition and utilization of lignocellulosic biomass present in the plant tissues are driven by a series of carbohydrate active enzymes (CAZymes) acting in concert. As the non-catalytic domains widely found in the modular CAZymes, carbohydrate-binding modules (CBMs) are intimately associated with catalytic domains (CDs) that effect the diverse hydrolytic reactions. The CBMs function as auxiliary components for the recognition, adhesion, and depolymerization of the complex substrate mediated by the associated CDs. Therefore, CBMs are deemed as significant biotools available for enzyme engineering, especially to facilitate the enzymatic hydrolysis of dense and insoluble plant tissues to acquire more fermentable sugars. This review aims at presenting the taxonomies and biological properties of the CBMs currently curated in the CAZy database. The molecular mechanisms that CBMs use in assisting the enzymatic hydrolysis of plant polysaccharides and the regulatory factors of CBM-substrate interactions are outlined in detail. In addition, guidelines for the rational designs of CBM-fused CAZymes are proposed. Furthermore, the potential to harness CBMs for industrial applications, especially in enzymatic pretreatment of the recalcitrant lignocellulose, is evaluated. It is envisaged that the ideas outlined herein will aid in the engineering and production of novel CBM-fused enzymes to facilitate efficient degradation of lignocellulosic biomass to easily fermentable sugars for production of value-added products, including biofuels.
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Affiliation(s)
- Qicheng Shi
- Laboratory of Gastrointestinal Microbiology, National Center for International Research on Animal Gut Nutrition, Nanjing Agricultural University, Nanjing 210095, China
| | - Ahmed M Abdel-Hamid
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, IL 61801, USA
| | - Zhanying Sun
- Laboratory of Gastrointestinal Microbiology, National Center for International Research on Animal Gut Nutrition, Nanjing Agricultural University, Nanjing 210095, China
| | - Yanfen Cheng
- Laboratory of Gastrointestinal Microbiology, National Center for International Research on Animal Gut Nutrition, Nanjing Agricultural University, Nanjing 210095, China.
| | - Tao Tu
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| | - Isaac Cann
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, IL 61801, USA; Department of Animal Science, University of Illinois at Urbana-Champaign, IL 61801, USA; Department of Microbiology, University of Illinois at Urbana-Champaign, IL 61801, USA; Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, IL 61801, USA; Center for East Asian and Pacific Studies, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Bin Yao
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Weiyun Zhu
- Laboratory of Gastrointestinal Microbiology, National Center for International Research on Animal Gut Nutrition, Nanjing Agricultural University, Nanjing 210095, China
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Liu J, Zhu J, Xu Q, Shi R, Liu C, Sun D, Liu W. Functional identification of two novel carbohydrate-binding modules of glucuronoxylanase CrXyl30 and their contribution to the lignocellulose saccharification. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:40. [PMID: 36890582 PMCID: PMC9996879 DOI: 10.1186/s13068-023-02290-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 02/28/2023] [Indexed: 03/10/2023]
Abstract
BACKGROUND Glycoside hydrolase (GH) family 30 xylanases are a distinct group of xylanases, most of which have a highly specific catalytic activity for glucuronoxylan. Since GH30 xylanases do not normally carry carbohydrate-binding modules (CBMs), our knowledge of the function of their CBMs is lacking. RESULTS In this work, the CBM functions of CrXyl30 were investigated. CrXyl30 was a GH30 glucuronoxylanase containing tandem CBM13 (CrCBM13) and CBM2 (CrCBM2) at its C terminus, which was identified in a lignocellulolytic bacterial consortium previously. Both CBMs could bind insoluble and soluble xylan, with CrCBM13 having binding specificity for the xylan with L-arabinosyl substitutions, whereas CrCBM2 targeted L-arabinosyl side chains themselves. Such binding abilities of these two CBMs were completely different from other CBMs in their respective families. Phylogenetic analysis also suggested that both CrCBM13 and CrCBM2 belong to novel branches. Inspection of the simulated structure of CrCBM13 identified a pocket that just accommodates the side chain of 3(2)-alpha-L-arabinofuranosyl-xylotriose, which forms hydrogen bonds with three of the five amino acid residues involved in ligand interaction. The truncation of either CrCBM13 or CrCBM2 did not alter the substrate specificity and optimal reaction conditions of CrXyl30, whereas truncation of CrCBM2 decreased the kcat/Km value by 83% (± 0%). Moreover, the absence of CrCBM2 and CrCBM13 resulted in a 5% (± 1%) and a 7% (± 0%) decrease, respectively, in the amount of reducing sugar released by the synergistic hydrolysis of delignified corncob whose hemicellulose is arabinoglucuronoxylan, respectively. In addition, fusion of CrCBM2 with a GH10 xylanase enhanced its catalytic activity against the branched xylan and improved the synergistic hydrolysis efficiency by more than fivefold when delignified corncob was used as substrate. Such a strong stimulation of hydrolysis resulted from the enhancement of hemicellulose hydrolysis on the one hand, and the cellulose hydrolysis is also improved according to the lignocellulose conversion rate measured by HPLC. CONCLUSIONS This study identifies the functions of two novel CBMs in CrXyl30 and shows the good potential of such CBMs specific for branched ligands in the development of efficient enzyme preparations.
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Affiliation(s)
- Jiawen Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai Road, Tongshan New District, Xuzhou, 221116 Jiangsu China
| | - Jingrong Zhu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai Road, Tongshan New District, Xuzhou, 221116 Jiangsu China
| | - Qian Xu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai Road, Tongshan New District, Xuzhou, 221116 Jiangsu China
| | - Rui Shi
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai Road, Tongshan New District, Xuzhou, 221116 Jiangsu China
| | - Cong Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai Road, Tongshan New District, Xuzhou, 221116 Jiangsu China
| | - Di Sun
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai Road, Tongshan New District, Xuzhou, 221116 Jiangsu China
| | - Weijie Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai Road, Tongshan New District, Xuzhou, 221116 Jiangsu China
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Zhang Z, Dong M, Zallot R, Blackburn GM, Wang N, Wang C, Chen L, Baumann P, Wu Z, Wang Z, Fan H, Roth C, Jin Y, He Y. Mechanistic and Structural Insights into the Specificity and Biological Functions of Bacterial Sulfoglycosidases. ACS Catal 2022. [DOI: 10.1021/acscatal.2c05405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Zhen Zhang
- Key Laboratory of Synthetic and Natural Functional Molecule, College of Chemistry and Materials Science, Northwest University, Xi’an 710127, P. R. China
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, U.K
| | - Mochen Dong
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, U.K
| | - Rémi Zallot
- Institute of Life Sciences, Swansea University Medical School, Swansea SA2 8PP, U.K
| | - George Michael Blackburn
- School of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, U.K
| | - Nini Wang
- Key Laboratory of Synthetic and Natural Functional Molecule, College of Chemistry and Materials Science, Northwest University, Xi’an 710127, P. R. China
| | - Chengjian Wang
- Glycobiology and Glycotechnology Research Center, College of Food Science and Technology, Northwest University, Xi’an 710069, P. R. China
| | - Long Chen
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, U.K
| | - Patrick Baumann
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, U.K
| | - Zuyan Wu
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, U.K
| | - Zhongfu Wang
- Glycobiology and Glycotechnology Research Center, College of Food Science and Technology, Northwest University, Xi’an 710069, P. R. China
| | - Haiming Fan
- Key Laboratory of Synthetic and Natural Functional Molecule, College of Chemistry and Materials Science, Northwest University, Xi’an 710127, P. R. China
| | - Christian Roth
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Arnimallee 22, 14195 Berlin, German
| | - Yi Jin
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, U.K
| | - Yuan He
- Key Laboratory of Synthetic and Natural Functional Molecule, College of Chemistry and Materials Science, Northwest University, Xi’an 710127, P. R. China
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Liu J, Xu Q, Wu Y, Sun D, Zhu J, Liu C, Liu W. Carbohydrate-binding modules of ChiB and ChiC promote the chitinolytic system of Serratia marcescens BWL1001. Enzyme Microb Technol 2022; 162:110118. [DOI: 10.1016/j.enzmictec.2022.110118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022]
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9
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Metatranscriptome Profiling of a Specialized Microbial Consortium during the Degradation of Nixtamalized Maize Pericarp. Microbiol Spectr 2022; 10:e0231821. [PMID: 34985337 PMCID: PMC8729791 DOI: 10.1128/spectrum.02318-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Lignocellulose degradation by microbial consortia is multifactorial; hence, it must be analyzed from a holistic perspective. In this study, the temporal transcriptional activity of consortium PM-06, a nixtamalized maize pericarp (NMP) degrader, was determined and related to structural and physicochemical data to give insights into the mechanism used to degrade this substrate. Transcripts were described in terms of metabolic profile, carbohydrate-active enzyme (CAZyme) annotation, and taxonomic affiliation. The PM-06 gene expression pattern was closely related to the differential rates of degradation. The environmental and physiological conditions preceding high-degradation periods were crucial for CAZyme expression. The onset of degradation preceded the period with the highest degradation rate in the whole process, and in this time, several CAZymes were upregulated. Functional analysis of expressed CAZymes indicated that PM-06 overcomes NMP recalcitrance through modular enzymes operating at the proximity of the insoluble substrate. Increments in the diversity of expressed modular CAZymes occurred in the last stages of degradation where the substrate is more recalcitrant and environmental conditions are stressing. Taxonomic affiliation of CAZyme transcripts indicated that Paenibacillus macerans was fundamental for degradation. This microorganism established synergistic relationships with Bacillus thuringiensis for the degradation of cellulose and hemicellulose and with Microbacterium, Leifsonia, and Nocardia for the saccharification of oligosaccharides. IMPORTANCE Nixtamalized maize pericarp is an abundant residue of the tortilla industry. Consortium PM-06 efficiently degraded this substrate in 192 h. In this work, the temporal transcriptional profile of PM-06 was determined. Findings indicated that differential degradation rates are important sample selection criteria since they were closely related to the expression of carbohydrate-active enzymes (CAZymes). The initial times of degradation were crucial for the consumption of nixtamalized pericarp. A transcriptional profile at the onset of degradation is reported for the first time. Diverse CAZyme genes were rapidly transcribed after inoculation to produce different enzymes that participated in the stage with the highest degradation rate in the whole process. This study provides information about the regulation of gene expression and mechanisms used by PM-06 to overcome recalcitrance. These findings are useful in the design of processes and enzyme cocktails for the degradation of this abundant substrate.
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10
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Liu J, Sun D, Zhu J, Liu C, Liu W. Carbohydrate-binding modules targeting branched polysaccharides: overcoming side-chain recalcitrance in a non-catalytic approach. BIORESOUR BIOPROCESS 2021; 8:28. [PMID: 38650221 PMCID: PMC10992016 DOI: 10.1186/s40643-021-00381-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 04/07/2021] [Indexed: 12/25/2022] Open
Abstract
Extensive decoration of backbones is a major factor resulting in resistance of enzymatic conversion in hemicellulose and other branched polysaccharides. Employing debranching enzymes is the main strategy to overcome this kind of recalcitrance at present. A carbohydrate-binding module (CBM) is a contiguous amino acid sequence that can promote the binding of enzymes to various carbohydrates, thereby facilitating enzymatic hydrolysis. According to previous studies, CBMs can be classified into four types based on their preference in ligand type, where Type III and IV CBMs prefer to branched polysaccharides than the linear and thus are able to specifically enhance the hydrolysis of substrates containing side chains. With a role in dominating the hydrolysis of branched substrates, Type III and IV CBMs could represent a non-catalytic approach in overcoming side-chain recalcitrance.
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Affiliation(s)
- Jiawen Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No. 101, Shanghai Road, Tongshan New District, Xuzhou, 221116, Jiangsu, China
| | - Di Sun
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No. 101, Shanghai Road, Tongshan New District, Xuzhou, 221116, Jiangsu, China
| | - Jingrong Zhu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No. 101, Shanghai Road, Tongshan New District, Xuzhou, 221116, Jiangsu, China
| | - Cong Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No. 101, Shanghai Road, Tongshan New District, Xuzhou, 221116, Jiangsu, China.
| | - Weijie Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No. 101, Shanghai Road, Tongshan New District, Xuzhou, 221116, Jiangsu, China.
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11
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Glasgow EM, Kemna EI, Bingman CA, Ing N, Deng K, Bianchetti CM, Takasuka TE, Northen TR, Fox BG. A structural and kinetic survey of GH5_4 endoglucanases reveals determinants of broad substrate specificity and opportunities for biomass hydrolysis. J Biol Chem 2021; 295:17752-17769. [PMID: 33454012 DOI: 10.1074/jbc.ra120.015328] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 10/15/2020] [Indexed: 11/06/2022] Open
Abstract
Broad-specificity glycoside hydrolases (GHs) contribute to plant biomass hydrolysis by degrading a diverse range of polysaccharides, making them useful catalysts for renewable energy and biocommodity production. Discovery of new GHs with improved kinetic parameters or more tolerant substrate-binding sites could increase the efficiency of renewable bioenergy production even further. GH5 has over 50 subfamilies exhibiting selectivities for reaction with β-(1,4)-linked oligo- and polysaccharides. Among these, subfamily 4 (GH5_4) contains numerous broad-selectivity endoglucanases that hydrolyze cellulose, xyloglucan, and mixed-linkage glucans. We previously surveyed the whole subfamily and found over 100 new broad-specificity endoglucanases, although the structural origins of broad specificity remained unclear. A mechanistic understanding of GH5_4 substrate specificity would help inform the best protein design strategies and the most appropriate industrial application of broad-specificity endoglucanases. Here we report structures of 10 new GH5_4 enzymes from cellulolytic microbes and characterize their substrate selectivity using normalized reducing sugar assays and MS. We found that GH5_4 enzymes have the highest catalytic efficiency for hydrolysis of xyloglucan, glucomannan, and soluble β-glucans, with opportunistic secondary reactions on cellulose, mannan, and xylan. The positions of key aromatic residues determine the overall reaction rate and breadth of substrate tolerance, and they contribute to differences in oligosaccharide cleavage patterns. Our new composite model identifies several critical structural features that confer broad specificity and may be readily engineered into existing industrial enzymes. We demonstrate that GH5_4 endoglucanases can have broad specificity without sacrificing high activity, making them a valuable addition to the biomass deconstruction toolset.
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Affiliation(s)
- Evan M Glasgow
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA
| | - Elias I Kemna
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA
| | - Craig A Bingman
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA
| | - Nicole Ing
- Joint BioEnergy Institute, Emeryville, California, USA; Sandia National Laboratories, Livermore, California, USA
| | - Kai Deng
- Joint BioEnergy Institute, Emeryville, California, USA; Sandia National Laboratories, Livermore, California, USA
| | - Christopher M Bianchetti
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA
| | | | - Trent R Northen
- Joint BioEnergy Institute, Emeryville, California, USA; Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Brian G Fox
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA.
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12
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Li K, Jiang C, Tan H, Li J, Xu Y, Tang D, Zhao X, Liu Q, Li J, Yin H. Identification and characterization of a novel glucomannanase from Paenibacillus polymyxa. 3 Biotech 2021; 11:129. [PMID: 33680694 PMCID: PMC7892656 DOI: 10.1007/s13205-021-02676-0] [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: 11/05/2020] [Accepted: 02/01/2021] [Indexed: 10/22/2022] Open
Abstract
Konjac glucomannan oligosaccharide has attracted much attention due to its broad biological activities. Specific glucomannan degrading enzymes are effective tools for the production of oligosaccharides from konjac glucomannan. However, there are still few reports of commercial enzymes that can specifically degrade konjac glucomannan. The gene ppgluB encoding a glucomannanase consisting of 553 amino acids (61.5 kDa) from Paenibacillus polymyxa 3-3 was cloned and heterologous expressed in Escherichia coli BL21 (DE3). The recombinant PpGluB showed high specificity for the degradation of konjac glucomannan. Moreover, the hydrolytic products of PpGluB degrade konjac glucomannan were a series of oligosaccharides with degrees of polymerisation of 2-12. Furthermore, the biochemical properties indicated that PpGluB is the optimal active at 45 to 55 °C and pH 5.0-6.0, and shows highly pH stability over a very broad pH range. The present characteristics indicated that PpGluB is a potential tool to be used to produce oligosaccharides from konjac glucomannan.
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Affiliation(s)
- Kuikui Li
- Key Laboratory of Se-enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs, National-Local Joint Engineering Laboratory of Se-enriched Food Development, Ankang, 725000 Shaanxi China
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, CAS, Dalian, 116023 China
| | - Chaofeng Jiang
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, CAS, Dalian, 116023 China
| | - Haidong Tan
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, CAS, Dalian, 116023 China
| | - Junyan Li
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, CAS, Dalian, 116023 China
| | - Yali Xu
- Key Laboratory of Se-enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs, National-Local Joint Engineering Laboratory of Se-enriched Food Development, Ankang, 725000 Shaanxi China
| | - Dejian Tang
- Key Laboratory of Se-enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs, National-Local Joint Engineering Laboratory of Se-enriched Food Development, Ankang, 725000 Shaanxi China
| | - Xiaoming Zhao
- Key Laboratory of Se-enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs, National-Local Joint Engineering Laboratory of Se-enriched Food Development, Ankang, 725000 Shaanxi China
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, CAS, Dalian, 116023 China
| | - Qishun Liu
- Key Laboratory of Se-enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs, National-Local Joint Engineering Laboratory of Se-enriched Food Development, Ankang, 725000 Shaanxi China
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, CAS, Dalian, 116023 China
| | - Jianguo Li
- Key Laboratory of Se-enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs, National-Local Joint Engineering Laboratory of Se-enriched Food Development, Ankang, 725000 Shaanxi China
- Ankang Agro-Tech Extension and Service Center, Ankang, 725000 Shaanxi China
| | - Heng Yin
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, CAS, Dalian, 116023 China
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13
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Sidar A, Albuquerque ED, Voshol GP, Ram AFJ, Vijgenboom E, Punt PJ. Carbohydrate Binding Modules: Diversity of Domain Architecture in Amylases and Cellulases From Filamentous Microorganisms. Front Bioeng Biotechnol 2020; 8:871. [PMID: 32850729 PMCID: PMC7410926 DOI: 10.3389/fbioe.2020.00871] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/07/2020] [Indexed: 12/11/2022] Open
Abstract
Enzymatic degradation of abundant renewable polysaccharides such as cellulose and starch is a field that has the attention of both the industrial and scientific community. Most of the polysaccharide degrading enzymes are classified into several glycoside hydrolase families. They are often organized in a modular manner which includes a catalytic domain connected to one or more carbohydrate-binding modules. The carbohydrate-binding modules (CBM) have been shown to increase the proximity of the enzyme to its substrate, especially for insoluble substrates. Therefore, these modules are considered to enhance enzymatic hydrolysis. These properties have played an important role in many biotechnological applications with the aim to improve the efficiency of polysaccharide degradation. The domain organization of glycoside hydrolases (GHs) equipped with one or more CBM does vary within organisms. This review comprehensively highlights the presence of CBM as ancillary modules and explores the diversity of GHs carrying one or more of these modules that actively act either on cellulose or starch. Special emphasis is given to the cellulase and amylase distribution within the filamentous microorganisms from the genera of Streptomyces and Aspergillus that are well known to have a great capacity for secreting a wide range of these polysaccharide degrading enzyme. The potential of the CBM and other ancillary domains for the design of improved polysaccharide decomposing enzymes is discussed.
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Affiliation(s)
- Andika Sidar
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Department of Food Science and Agricultural Product Technology, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Erica D Albuquerque
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Sun Pharmaceutical Industries Europe BV., Hoofddorp, Netherlands
| | - Gerben P Voshol
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Dutch DNA Biotech B.V., Utrecht, Netherlands
| | - Arthur F J Ram
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands
| | - Erik Vijgenboom
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands
| | - Peter J Punt
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Dutch DNA Biotech B.V., Utrecht, Netherlands
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14
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Zhou S, Ko TP, Huang JW, Liu W, Zheng Y, Wu S, Wang Q, Xie Z, Liu Z, Chen CC, Guo RT. Structure of a gut microbial diltiazem-metabolizing enzyme suggests possible substrate binding mode. Biochem Biophys Res Commun 2020; 527:799-804. [PMID: 32423809 DOI: 10.1016/j.bbrc.2020.04.116] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 04/22/2020] [Indexed: 10/24/2022]
Abstract
When administrated orally, the vasodilating drug diltiazem can be metabolized into diacetyl diltiazem in the presence of Bacteroides thetaiotaomicron, a human gut microbe. The removal of acetyl group from the parent drug is carried out by the GDSL/SGNH-family hydrolase BT4096. Here the crystal structure of the enzyme was solved by mercury soaking and single-wavelength anomalous diffraction. The protein folds into two parts. The N-terminal part comprises the catalytic domain which is similar to other GDSL/SGNH hydrolases. The flanking C-terminal part is made up of a β-barrel subdomain and an α-helical subdomain. Structural comparison shows that the catalytic domain is most akin to acetyl-xylooligosaccharide esterase and allows a plausible binding mode of diltiazem to be proposed. The β-barrel subdomain is similar in topology to the immunoglobulin-like domains, including some carbohydrate-binding modules, of various bacterial glycoside hydrolases. Consequently, BT4096 might originally function as an oligosaccharide deacetylase with additional subdomains that could enhance substrate binding, and it acts on diltiazem just by accident.
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Affiliation(s)
- Shuyu Zhou
- School of Life Science, University of Science and Technology of China, Anhui, 230026, China; Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Tzu-Ping Ko
- Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan.
| | - Jian-Wen Huang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Weidong Liu
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Yingying Zheng
- Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Shan Wu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Qian Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Zhenzhen Xie
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Ziwei Liu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Chun-Chi Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China.
| | - Rey-Ting Guo
- School of Life Science, University of Science and Technology of China, Anhui, 230026, China; Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China.
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15
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Possible beneficial effects of xyloglucan from its degradation by gut microbiota. Trends Food Sci Technol 2020. [DOI: 10.1016/j.tifs.2020.01.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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16
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Ribeiro DO, Viegas A, Pires VMR, Medeiros‐Silva J, Bule P, Chai W, Marcelo F, Fontes CMGA, Cabrita EJ, Palma AS, Carvalho AL. Molecular basis for the preferential recognition of β1,3‐1,4‐glucans by the family 11 carbohydrate‐binding module from
Clostridium thermocellum. FEBS J 2019; 287:2723-2743. [DOI: 10.1111/febs.15162] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/09/2019] [Accepted: 11/29/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Diana O. Ribeiro
- UCIBIO Departamento de Química Faculdade de Ciências e Tecnologia Universidade NOVA de Lisboa Caparica Portugal
| | - Aldino Viegas
- UCIBIO Departamento de Química Faculdade de Ciências e Tecnologia Universidade NOVA de Lisboa Caparica Portugal
| | - Virgínia M. R. Pires
- CIISA ‐ Faculdade de Medicina Veterinária Universidade de Lisboa Avenida da Universidade Técnica Lisboa Portugal
| | - João Medeiros‐Silva
- UCIBIO Departamento de Química Faculdade de Ciências e Tecnologia Universidade NOVA de Lisboa Caparica Portugal
| | - Pedro Bule
- CIISA ‐ Faculdade de Medicina Veterinária Universidade de Lisboa Avenida da Universidade Técnica Lisboa Portugal
| | - Wengang Chai
- Glycosciences Laboratory Department of Medicine Imperial College London London UK
| | - Filipa Marcelo
- UCIBIO Departamento de Química Faculdade de Ciências e Tecnologia Universidade NOVA de Lisboa Caparica Portugal
| | - Carlos M. G. A. Fontes
- CIISA ‐ Faculdade de Medicina Veterinária Universidade de Lisboa Avenida da Universidade Técnica Lisboa Portugal
- NZYTech Genes & Enzymes Campus do Lumiar Estrada do Paço do Lumiar Edifício E Lisboa Portugal
| | - Eurico J. Cabrita
- UCIBIO Departamento de Química Faculdade de Ciências e Tecnologia Universidade NOVA de Lisboa Caparica Portugal
| | - Angelina S. Palma
- UCIBIO Departamento de Química Faculdade de Ciências e Tecnologia Universidade NOVA de Lisboa Caparica Portugal
- Glycosciences Laboratory Department of Medicine Imperial College London London UK
| | - Ana Luísa Carvalho
- UCIBIO Departamento de Química Faculdade de Ciências e Tecnologia Universidade NOVA de Lisboa Caparica Portugal
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17
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Liu T, Yi ZW, Zeng RY, Jiang W, Zhang G. The first characterization of a Ca2+-dependent carbohydrate-binding module of β-1,3-xylanase from Flammeovirga pacifica. Enzyme Microb Technol 2019; 131:109418. [DOI: 10.1016/j.enzmictec.2019.109418] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 12/19/2022]
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18
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Characterization of an alkali-stable xyloglucanase/mixed-linkage β-glucanase Pgl5A from Paenibacillus sp. S09. Int J Biol Macromol 2019; 140:1158-1166. [DOI: 10.1016/j.ijbiomac.2019.08.210] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/24/2019] [Accepted: 08/24/2019] [Indexed: 11/15/2022]
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19
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Ma J, Li Q, Tan H, Jiang H, Li K, Zhang L, Shi Q, Yin H. Unique N-glycosylation of a recombinant exo-inulinase from Kluyveromyces cicerisporus and its effect on enzymatic activity and thermostability. J Biol Eng 2019; 13:81. [PMID: 31737090 PMCID: PMC6844067 DOI: 10.1186/s13036-019-0215-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 10/16/2019] [Indexed: 01/05/2023] Open
Abstract
Background Inulinase can hydrolyze polyfructan into high-fructose syrups and fructoligosaccharides, which are widely used in food, the medical industry and the biorefinery of Jerusalem artichoke. In the present study, a recombinant exo-inulinase (rKcINU1), derived from Kluyveromyces cicerisporus CBS4857, was proven as an N-linked glycoprotein, and the removal of N-linked glycan chains led to reduced activity. Results Five N-glycosylation sites with variable high mannose-type oligosaccharides (Man3–9GlcNAc2) were confirmed in the rKcINU1. The structural modeling showed that all five glycosylation sites (Asn-362, Asn-370, Asn-399, Asn-467 and Asn-526) were located at the C-terminus β-sandwich domain, which has been proven to be more conducive to the occurrence of glycosylation modification than the N-terminus domain. Single-site N-glycosylation mutants with Asn substituted by Gln were obtained, and the Mut with all five N-glycosylation sites removed was constructed, which resulted in the loss of all enzyme activity. Interestingly, the N362Q led to an 18% increase in the specific activity against inulin, while a significant decrease in thermostability (2.91 °C decrease in Tm) occurred, and other single mutations resulted in the decrease in the specific activity to various extents, among which N467Q demonstrated the lowest enzyme activity. Conclusion The increased enzyme activity in N362Q, combined with thermostability testing, 3D modeling, kinetics data and secondary structure analysis, implied that the N-linked glycan chains at the Asn-362 position functioned negatively, mainly as a type of steric hindrance toward its adjacent N-glycans to bring rigidity. Meanwhile, the N-glycosylation at the other four sites positively regulated enzyme activity caused by altered substrate affinity by means of fine-tuning the β-sandwich domain configuration. This may have facilitated the capture and transfer of substrates to the enzyme active cavity, in a manner quite similar to that of carbohydrate binding modules (CBMs), i.e. the chains endowed the β-sandwich domain with the functions of CBM. This study discovered a unique C-terminal sequence which is more favorable to glycosylation, thereby casting a novel view for glycoengineering of enzymes from fungi via redesigning the amino acid sequence at the C-terminal domain, so as to optimize the enzymatic properties.
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Affiliation(s)
- Junyan Ma
- 1Natural Products and Glyco-Biotechnology Research Group, Liaoning Province Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China.,2Liaoning Province Key Laboratory of Bio-Organic Chemistry, Dalian University, Dalian, 116622 China
| | - Qian Li
- 2Liaoning Province Key Laboratory of Bio-Organic Chemistry, Dalian University, Dalian, 116622 China
| | - Haidong Tan
- 1Natural Products and Glyco-Biotechnology Research Group, Liaoning Province Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China
| | - Hao Jiang
- 3Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China
| | - Kuikui Li
- 1Natural Products and Glyco-Biotechnology Research Group, Liaoning Province Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China
| | - Lihua Zhang
- 3Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China
| | - Quan Shi
- 3Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China
| | - Heng Yin
- 1Natural Products and Glyco-Biotechnology Research Group, Liaoning Province Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China
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20
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Glasgow EM, Vander Meulen KA, Takasuka TE, Bianchetti CM, Bergeman LF, Deutsch S, Fox BG. Extent and Origins of Functional Diversity in a Subfamily of Glycoside Hydrolases. J Mol Biol 2019; 431:1217-1233. [PMID: 30685401 DOI: 10.1016/j.jmb.2019.01.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 10/19/2018] [Accepted: 01/16/2019] [Indexed: 12/16/2022]
Abstract
Some glycoside hydrolases have broad specificity for hydrolysis of glycosidic bonds, potentially increasing their functional utility and flexibility in physiological and industrial applications. To deepen the understanding of the structural and evolutionary driving forces underlying specificity patterns in glycoside hydrolase family 5, we quantitatively screened the activity of the catalytic core domains from subfamily 4 (GH5_4) and closely related enzymes on four substrates: lichenan, xylan, mannan, and xyloglucan. Phylogenetic analysis revealed that GH5_4 consists of three major clades, and one of these clades, referred to here as clade 3, displayed average specific activities of 4.2 and 1.2 U/mg on lichenan and xylan, approximately 1 order of magnitude larger than the average for active enzymes in clades 1 and 2. Enzymes in clade 3 also more consistently met assay detection thresholds for reaction with all four substrates. We also identified a subfamily-wide positive correlation between lichenase and xylanase activities, as well as a weaker relationship between lichenase and xyloglucanase. To connect these results to structural features, we used the structure of CelE from Hungateiclostridium thermocellum (PDB 4IM4) as an example clade 3 enzyme with activities on all four substrates. Comparison of the sequence and structure of this enzyme with others throughout GH5_4 and neighboring subfamilies reveals at least two residues (H149 and W203) that are linked to strong activity across the substrates. Placing GH5_4 in context with other related subfamilies, we highlight several possibilities for the ongoing evolutionary specialization of GH5_4 enzymes.
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Affiliation(s)
- Evan M Glasgow
- Great Lakes Bioenergy Research Center, Madison, WI 53706 USA; Department of Biochemistry, University of Wisconsin, Madison, WI 53706 USA
| | - Kirk A Vander Meulen
- Great Lakes Bioenergy Research Center, Madison, WI 53706 USA; Department of Biochemistry, University of Wisconsin, Madison, WI 53706 USA
| | - Taichi E Takasuka
- Great Lakes Bioenergy Research Center, Madison, WI 53706 USA; Department of Biochemistry, University of Wisconsin, Madison, WI 53706 USA; Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589 Japan
| | - Christopher M Bianchetti
- Great Lakes Bioenergy Research Center, Madison, WI 53706 USA; Department of Biochemistry, University of Wisconsin, Madison, WI 53706 USA; Department of Chemistry, University of Wisconsin, Oshkosh, 54901 USA
| | - Lai F Bergeman
- Great Lakes Bioenergy Research Center, Madison, WI 53706 USA; Department of Biochemistry, University of Wisconsin, Madison, WI 53706 USA
| | | | - Brian G Fox
- Great Lakes Bioenergy Research Center, Madison, WI 53706 USA; Department of Biochemistry, University of Wisconsin, Madison, WI 53706 USA.
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21
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A tri-enzyme co-immobilized magnetic complex: Process details, kinetics, thermodynamics and applications. Int J Biol Macromol 2018; 118:1781-1795. [DOI: 10.1016/j.ijbiomac.2018.07.022] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 06/14/2018] [Accepted: 07/07/2018] [Indexed: 01/09/2023]
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22
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Ben Hmad I, Gargouri A. Two Distinct Hydrolysis Mechanisms of the Neutral Endoglucanases EG1 and EG2 of Stachybotrys microspora. Catal Letters 2018. [DOI: 10.1007/s10562-018-2410-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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23
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Daas MJA, Nijsse B, van de Weijer AHP, Groenendaal BWAJ, Janssen F, van der Oost J, van Kranenburg R. Engineering Geobacillus thermodenitrificans to introduce cellulolytic activity; expression of native and heterologous cellulase genes. BMC Biotechnol 2018; 18:42. [PMID: 29945583 PMCID: PMC6020330 DOI: 10.1186/s12896-018-0453-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 06/14/2018] [Indexed: 11/28/2022] Open
Abstract
Background Consolidated bioprocessing (CBP) is a cost-effective approach for the conversion of lignocellulosic biomass to biofuels and biochemicals. The enzymatic conversion of cellulose to glucose requires the synergistic action of three types of enzymes: exoglucanases, endoglucanases and β-glucosidases. The thermophilic, hemicellulolytic Geobacillus thermodenitrificans T12 was shown to harbor desired features for CBP, although it lacks the desired endo and exoglucanases required for the conversion of cellulose. Here, we report the expression of both endoglucanase and exoglucanase encoding genes by G. thermodenitrificans T12, in an initial attempt to express cellulolytic enzymes that complement the enzymatic machinery of this strain. Results A metagenome screen was performed on 73 G. thermodenitrificans strains using HMM profiles of all known CAZy families that contain endo and/or exoglucanases. Two putative endoglucanases, GE39 and GE40, belonging to glucoside hydrolase family 5 (GH5) were isolated and expressed in both E. coli and G. thermodenitrificans T12. Structure modeling of GE39 revealed a folding similar to a GH5 exo-1,3-β-glucanase from S. cerevisiae. However, we determined GE39 to be a β-xylosidase having pronounced activity towards p-nitrophenyl-β-d-xylopyranoside. Structure modelling of GE40 revealed its protein architecture to be similar to a GH5 endoglucanase from B. halodurans, and its endoglucanase activity was confirmed by enzymatic activity against 2-hydroxyethylcellulose, carboxymethylcellulose and barley β-glucan. Additionally, we introduced expression constructs into T12 containing Geobacillus sp. 70PC53 endoglucanase gene celA and both endoglucanase genes (M1 and M2) from Geobacillus sp. WSUCF1. Finally, we introduced expression constructs into T12 containing the C. thermocellum exoglucanases celK and celS genes and the endoglucanase celC gene. Conclusions We identified a novel G. thermodenitrificans β-xylosidase (GE39) and a novel endoglucanase (GE40) using a metagenome screen based on multiple HMM profiles. We successfully expressed both genes in E. coli and functionally expressed the GE40 endoglucanase in G. thermodenitrificans T12. Additionally, the heterologous production of active CelK, a C. thermocellum derived exoglucanase, and CelA, a Geobacillus derived endoglucanase, was demonstrated with strain T12. The native hemicellulolytic activity and the heterologous cellulolytic activity described in this research provide a good basis for the further development of G. thermodenitrificans T12 as a host for consolidated bioprocessing. Electronic supplementary material The online version of this article (10.1186/s12896-018-0453-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Martinus J A Daas
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Bart Nijsse
- Laboratory of Systems and Synthetic Biology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | | | - Bart W A J Groenendaal
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Fons Janssen
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - John van der Oost
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Richard van Kranenburg
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands. .,Corbion, Arkelsedijk 46, 4206, AC, Gorinchem, The Netherlands.
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A flexible loop for mannan recognition and activity enhancement in a bifunctional glycoside hydrolase family 5. Biochim Biophys Acta Gen Subj 2018; 1862:513-521. [DOI: 10.1016/j.bbagen.2017.11.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 10/25/2017] [Accepted: 11/02/2017] [Indexed: 11/18/2022]
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25
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Carbohydrate active enzyme domains from extreme thermophiles: components of a modular toolbox for lignocellulose degradation. Extremophiles 2017; 22:1-12. [PMID: 29110088 DOI: 10.1007/s00792-017-0974-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/24/2017] [Indexed: 02/06/2023]
Abstract
Lignocellulosic biomass is a promising feedstock for the manufacture of biodegradable and renewable bioproducts. However, the complex lignocellulosic polymeric structure of woody tissue is difficult to access without extensive industrial pre-treatment. Enzyme processing of partly depolymerised biomass is an established technology, and there is evidence that high temperature (extremely thermophilic) lignocellulose degrading enzymes [carbohydrate active enzymes (CAZymes)] may enhance processing efficiency. However, wild-type thermophilic CAZymes will not necessarily be functionally optimal under industrial pre-treatment conditions. With recent advances in synthetic biology, it is now potentially possible to build CAZyme constructs from individual protein domains, tailored to the conditions of specific industrial processes. In this review, we identify a 'toolbox' of thermostable CAZyme domains from extremely thermophilic organisms and highlight recent advances in CAZyme engineering which will allow for the rational design of CAZymes tailored to specific aspects of lignocellulose digestion.
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Impact of Module-X2 and Carbohydrate Binding Module-3 on the catalytic activity of associated glycoside hydrolases towards plant biomass. Sci Rep 2017. [PMID: 28623337 PMCID: PMC5473887 DOI: 10.1038/s41598-017-03927-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Cellulolytic enzymes capable of hydrolyzing plant biomass are secreted by microbial cells specifically in response to the carbon substrate present in the environment. These enzymes consist of a catalytic domain, generally appended to one or more non-catalytic Carbohydrate Binding Module (CBM), which enhances their activity towards recalcitrant biomass. In the present study, the genome of a cellulolytic microbe Paenibacillus polymyxa A18 was annotated for the presence of CBMs and analyzed their expression in response to the plant biomass and model polysaccharides Avicel, CMC and xylan using quantitative PCR. A gene that encodes X2-CBM3 was found to be maximally induced in response to the biomass and crystalline substrate Avicel. Association of X2-CBM3 with xyloglucanase and endoglucanase led to up to 4.6-fold increase in activity towards insoluble substrates. In the substrate binding study, module X2 showed a higher affinity towards biomass and phosphoric acid swollen cellulose, whereas CBM3 showed a higher affinity towards Avicel. Further structural modeling of X2 also indicated its potential role in substrate binding. Our findings highlighted the role of module X2 along with CBM3 in assisting the enzyme catalysis of agricultural residue and paved the way to engineer glycoside hydrolases for superior activity.
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27
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Han YB, Chen LQ, Li Z, Tan YM, Feng Y, Yang GY. Structural Insights into the Broad Substrate Specificity of a Novel Endoglycoceramidase I Belonging to a New Subfamily of GH5 Glycosidases. J Biol Chem 2017; 292:4789-4800. [PMID: 28179425 DOI: 10.1074/jbc.m116.763821] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 01/11/2017] [Indexed: 01/27/2023] Open
Abstract
Endoglycoceramidases (EGCases) specifically hydrolyze the glycosidic linkage between the oligosaccharide and the ceramide moieties of various glycosphingolipids, and they have received substantial attention in the emerging field of glycosphingolipidology. However, the mechanism regulating the strict substrate specificity of these GH5 glycosidases has not been identified. In this study, we report a novel EGCase I from Rhodococcus equi 103S (103S_EGCase I) with remarkably broad substrate specificity. Based on phylogenetic analyses, the enzyme may represent a new subfamily of GH5 glycosidases. The X-ray crystal structures of 103S_EGCase I alone and in complex with its substrates monosialodihexosylganglioside (GM3) and monosialotetrahexosylganglioside (GM1) enabled us to identify several structural features that may account for its broad specificity. Compared with EGCase II from Rhodococcus sp. M-777 (M777_EGCase II), which possesses strict substrate specificity, 103S_EGCase I possesses a longer α7-helix and a shorter loop 4, which forms a larger substrate-binding pocket that could accommodate more extended oligosaccharides. In addition, loop 2 and loop 8 of the enzyme adopt a more open conformation, which also enlarges the oligosaccharide-binding cavity. Based on this knowledge, a rationally designed experiment was performed to examine the substrate specificity of EGCase II. The truncation of loop 4 in M777_EGCase II increased its activity toward GM1 (163%). Remarkably, the S63G mutant of M777_EGCase II showed a broader substrate spectra and significantly increased activity toward bulky substrates (up to >1370-fold for fucosyl-GM1). Collectively, the results presented here reveal the exquisite substrate recognition mechanism of EGCases and provide an opportunity for further engineering of these enzymes.
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Affiliation(s)
- Yun-Bin Han
- From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.,the Shanghai Institute for Advanced Immunological Studies, ShanghaiTech University, Shanghai 200031, China, and
| | - Liu-Qing Chen
- From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhuo Li
- From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yu-Meng Tan
- From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yan Feng
- From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Guang-Yu Yang
- From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China, .,the Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), East China University of Science and Technology, Shanghai 200237, China
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28
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Verhertbruggen Y, Walker JL, Guillon F, Scheller HV. A Comparative Study of Sample Preparation for Staining and Immunodetection of Plant Cell Walls by Light Microscopy. FRONTIERS IN PLANT SCIENCE 2017; 8:1505. [PMID: 28900439 PMCID: PMC5581911 DOI: 10.3389/fpls.2017.01505] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 08/14/2017] [Indexed: 05/02/2023]
Abstract
Staining and immunodetection by light microscopy are methods widely used to investigate plant cell walls. The two techniques have been crucial to study the cell wall architecture in planta, its deconstruction by chemicals or cell wall-degrading enzymes. They have been instrumental in detecting the presence of cell types, in deciphering plant cell wall evolution and in characterizing plant mutants and transformants. The success of immunolabeling relies on how plant materials are embedded and sectioned. Agarose coating, wax and resin embedding are, respectively, associated with vibratome, microtome and ultramicrotome sectioning. Here, we have systematically carried out a comparative analysis of these three methods of sample preparation when they are applied for cell wall staining and cell wall immunomicroscopy. In order to help the plant community in understanding and selecting adequate methods of embedding and sectioning for cell wall immunodetection, we review in this article the advantages and limitations of these three methods. Moreover, we offer detailed protocols of embedding for studying plant materials through microscopy.
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Affiliation(s)
- Yves Verhertbruggen
- Joint BioEnergy Institute, Lawrence Berkeley National LaboratoryEmeryville, CA, United States
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National LaboratoryBerkeley, CA, United States
- Institut National de la Recherche Agronomique, UR 1268Nantes, France
- *Correspondence: Yves Verhertbruggen
| | - Jesse L. Walker
- Joint BioEnergy Institute, Lawrence Berkeley National LaboratoryEmeryville, CA, United States
- Department of Plant and Microbial Biology, University of California, BerkeleyBerkeley, CA, United States
| | - Fabienne Guillon
- Institut National de la Recherche Agronomique, UR 1268Nantes, France
| | - Henrik V. Scheller
- Joint BioEnergy Institute, Lawrence Berkeley National LaboratoryEmeryville, CA, United States
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National LaboratoryBerkeley, CA, United States
- Department of Plant and Microbial Biology, University of California, BerkeleyBerkeley, CA, United States
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29
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Rai R, Kaur B, Singh S, Di Falco M, Tsang A, Chadha BS. Evaluation of secretome of highly efficient lignocellulolytic Penicillium sp. Dal 5 isolated from rhizosphere of conifers. BIORESOURCE TECHNOLOGY 2016; 216:958-67. [PMID: 27341464 DOI: 10.1016/j.biortech.2016.06.040] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/04/2016] [Accepted: 06/06/2016] [Indexed: 05/23/2023]
Abstract
Penicillium sp. (Dal 5) isolated from rhizosphere of conifers from Dalhousie (Himachal Pradesh, India) was found to be an efficient cellulolytic strain. The culture under shake flask on CWR (cellulose, wheat bran and rice straw) medium produced appreciably higher levels of endoglucanase (35.69U/ml), β-glucosidase (4.20U/ml), cellobiohydrolase (2.86U/ml), FPase (1.2U/ml) and xylanase (115U/ml) compared to other Penicillium strains reported in literature. The mass spectroscopy analysis of Penicillium sp. Dal 5 secretome identified 108 proteins constituting an array of CAZymes including glycosyl hydrolases (GH) belonging to 24 different families, polysaccharide lyases (PL), carbohydrate esterases (CE), lytic polysaccharide mono-oxygenases (LPMO) in addition to swollenin and a variety of carbohydrate binding modules (CBM) indicating an elaborate genetic potential of this strain for hydrolysis of lignocellulosics. Further, the culture extract was evaluated for hydrolysis of alkali treated rice straw, wheat straw, bagasse and corn cob at 10% substrate loading rate.
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Affiliation(s)
- Rohit Rai
- Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, Punjab, India
| | - Baljit Kaur
- Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, Punjab, India
| | - Surender Singh
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Macros Di Falco
- Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada
| | - Adrian Tsang
- Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada
| | - B S Chadha
- Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, Punjab, India.
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30
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Labourel A, Crouch LI, Brás JLA, Jackson A, Rogowski A, Gray J, Yadav MP, Henrissat B, Fontes CMGA, Gilbert HJ, Najmudin S, Baslé A, Cuskin F. The Mechanism by Which Arabinoxylanases Can Recognize Highly Decorated Xylans. J Biol Chem 2016; 291:22149-22159. [PMID: 27531750 PMCID: PMC5063996 DOI: 10.1074/jbc.m116.743948] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Indexed: 12/15/2022] Open
Abstract
The enzymatic degradation of plant cell walls is an important biological process of increasing environmental and industrial significance. Xylan, a major component of the plant cell wall, consists of a backbone of β-1,4-xylose (Xylp) units that are often decorated with arabinofuranose (Araf) side chains. A large penta-modular enzyme, CtXyl5A, was shown previously to specifically target arabinoxylans. The mechanism of substrate recognition displayed by the enzyme, however, remains unclear. Here we report the crystal structure of the arabinoxylanase and the enzyme in complex with ligands. The data showed that four of the protein modules adopt a rigid structure, which stabilizes the catalytic domain. The C-terminal non-catalytic carbohydrate binding module could not be observed in the crystal structure, suggesting positional flexibility. The structure of the enzyme in complex with Xylp-β-1,4-Xylp-β-1,4-Xylp-[α-1,3-Araf]-β-1,4-Xylp showed that the Araf decoration linked O3 to the xylose in the active site is located in the pocket (−2* subsite) that abuts onto the catalytic center. The −2* subsite can also bind to Xylp and Arap, explaining why the enzyme can utilize xylose and arabinose as specificity determinants. Alanine substitution of Glu68, Tyr92, or Asn139, which interact with arabinose and xylose side chains at the −2* subsite, abrogates catalytic activity. Distal to the active site, the xylan backbone makes limited apolar contacts with the enzyme, and the hydroxyls are solvent-exposed. This explains why CtXyl5A is capable of hydrolyzing xylans that are extensively decorated and that are recalcitrant to classic endo-xylanase attack.
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Affiliation(s)
- Aurore Labourel
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Lucy I Crouch
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Joana L A Brás
- CIISA-Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal, NZYTech Genes & Enzymes, 1649-038 Lisboa, Portugal
| | - Adam Jackson
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Artur Rogowski
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Joseph Gray
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Madhav P Yadav
- the Eastern Regional Research Center, United States Department of Agriculture-Agricultural Research Service, Wyndmoor, Pennsylvania 19038
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques, UMR7857 CNRS, Aix-Marseille University, F-13288 Marseille, France, USC1408 Architecture et Fonction des Macromolécules Biologiques, INRA, F-13288 Marseille, France, and the Department of Biological Sciences, King Abdulaziz University, Jedda 21589, Saudi Arabia
| | - Carlos M G A Fontes
- CIISA-Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal, NZYTech Genes & Enzymes, 1649-038 Lisboa, Portugal
| | - Harry J Gilbert
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Shabir Najmudin
- CIISA-Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal,
| | - Arnaud Baslé
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom,
| | - Fiona Cuskin
- From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom,
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31
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Molecular characterization of a family 5 glycoside hydrolase suggests an induced-fit enzymatic mechanism. Sci Rep 2016; 6:23473. [PMID: 27032335 PMCID: PMC4817029 DOI: 10.1038/srep23473] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 02/25/2016] [Indexed: 11/25/2022] Open
Abstract
Glycoside hydrolases (GHs) play fundamental roles in the decomposition of lignocellulosic biomaterials. Here, we report the full-length structure of a cellulase from Bacillus licheniformis (BlCel5B), a member of the GH5 subfamily 4 that is entirely dependent on its two ancillary modules (Ig-like module and CBM46) for catalytic activity. Using X-ray crystallography, small-angle X-ray scattering and molecular dynamics simulations, we propose that the C-terminal CBM46 caps the distal N-terminal catalytic domain (CD) to establish a fully functional active site via a combination of large-scale multidomain conformational selection and induced-fit mechanisms. The Ig-like module is pivoting the packing and unpacking motions of CBM46 relative to CD in the assembly of the binding subsite. This is the first example of a multidomain GH relying on large amplitude motions of the CBM46 for assembly of the catalytically competent form of the enzyme.
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Abstract
The enzyme-catalysed degradation of oligo and polysaccharides is of considerable interest in many fields ranging from the fundamental–understanding the intrinsic chemical beauty–through to the applied, including diverse practical applications in medicine and biotechnology. Carbohydrates are the most stereochemically-complex biopolymer, and myriad different natural polysaccharides have led to evolution of multifaceted enzyme consortia for their degradation. The glycosidic bonds that link sugar monomers are among the most chemically-stable, yet enzymatically-labile, bonds in the biosphere. That glycoside hydrolases can achieve a rate enhancement (kcat/kuncat) >1017-fold provides testament to their remarkable proficiency and the sophistication of their catalysis reaction mechanisms. The last two decades have seen significant advances in the discovery of new glycosidase sequences, sequence-based classification into families and clans, 3D structures and reaction mechanisms, providing new insights into enzymatic catalysis. New impetus to these studies has been provided by the challenges inherent in plant and microbial polysaccharide degradation, both in the context of environmentally-sustainable routes to foods and biofuels, and increasingly in human nutrition. Study of the reaction mechanism of glycoside hydrolases has also inspired the development of enzyme inhibitors, both as mechanistic probes and increasingly as therapeutic agents. We are on the cusp of a new era where we are learning how to dovetail powerful computational techniques with structural and kinetic data to provide an unprecedented view of conformational details of enzyme action.
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33
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Crouch LI, Labourel A, Walton PH, Davies GJ, Gilbert HJ. The Contribution of Non-catalytic Carbohydrate Binding Modules to the Activity of Lytic Polysaccharide Monooxygenases. J Biol Chem 2016; 291:7439-49. [PMID: 26801613 PMCID: PMC4817175 DOI: 10.1074/jbc.m115.702365] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Indexed: 01/23/2023] Open
Abstract
Lignocellulosic biomass is a sustainable industrial substrate. Copper-dependent lytic polysaccharide monooxygenases (LPMOs) contribute to the degradation of lignocellulose and increase the efficiency of biofuel production. LPMOs can contain non-catalytic carbohydrate binding modules (CBMs), but their role in the activity of these enzymes is poorly understood. Here we explored the importance of CBMs in LPMO function. The family 2a CBMs of two monooxygenases,CfLPMO10 andTbLPMO10 fromCellulomonas fimiandThermobispora bispora, respectively, were deleted and/or replaced with CBMs from other proteins. The data showed that the CBMs could potentiate and, surprisingly, inhibit LPMO activity, and that these effects were both enzyme-specific and substrate-specific. Removing the natural CBM or introducingCtCBM3a, from theClostridium thermocellumcellulosome scaffoldin CipA, almost abolished the catalytic activity of the LPMOs against the cellulosic substrates. The deleterious effect of CBM removal likely reflects the importance of prolonged presentation of the enzyme on the surface of the substrate for efficient catalytic activity, as only LPMOs appended to CBMs bound tightly to cellulose. The negative impact ofCtCBM3a is in sharp contrast with the capacity of this binding module to potentiate the activity of a range of glycoside hydrolases including cellulases. The deletion of the endogenous CBM fromCfLPMO10 or the introduction of a family 10 CBM fromCellvibrio japonicusLPMO10B intoTbLPMO10 influenced the quantity of non-oxidized products generated, demonstrating that CBMs can modulate the mode of action of LPMOs. This study demonstrates that engineered LPMO-CBM hybrids can display enhanced industrially relevant oxygenations.
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Affiliation(s)
- Lucy I Crouch
- From the Institute for Cell and Molecular Biosciences, The Medical School Newcastle University, Newcastle upon Tyne NE2 4HH and
| | - Aurore Labourel
- From the Institute for Cell and Molecular Biosciences, The Medical School Newcastle University, Newcastle upon Tyne NE2 4HH and
| | - Paul H Walton
- the York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Gideon J Davies
- the York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Harry J Gilbert
- From the Institute for Cell and Molecular Biosciences, The Medical School Newcastle University, Newcastle upon Tyne NE2 4HH and
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Structural Insight of a Trimodular Halophilic Cellulase with a Family 46 Carbohydrate-Binding Module. PLoS One 2015; 10:e0142107. [PMID: 26562160 PMCID: PMC4643050 DOI: 10.1371/journal.pone.0142107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 10/16/2015] [Indexed: 01/08/2023] Open
Abstract
Cellulases are the key enzymes used in the biofuel industry. A typical cellulase contains a catalytic domain connected to a carbohydrate-binding module (CBM) through a flexible linker. Here we report the structure of an atypical trimodular cellulase which harbors a catalytic domain, a CBM46 domain and a rigid CBM_X domain between them. The catalytic domain shows the features of GH5 family, while the CBM46 domain has a sandwich-like structure. The catalytic domain and the CBM46 domain form an extended substrate binding cleft, within which several tryptophan residues are well exposed. Mutagenesis assays indicate that these residues are essential for the enzymatic activities. Gel affinity electrophoresis shows that these tryptophan residues are involved in the polysaccharide substrate binding. Also, electrostatic potential analysis indicates that almost the entire solvent accessible surface of CelB is negatively charged, which is consistent with the halophilic nature of this enzyme.
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McGregor N, Morar M, Fenger TH, Stogios P, Lenfant N, Yin V, Xu X, Evdokimova E, Cui H, Henrissat B, Savchenko A, Brumer H. Structure-Function Analysis of a Mixed-linkage β-Glucanase/Xyloglucanase from the Key Ruminal Bacteroidetes Prevotella bryantii B(1)4. J Biol Chem 2015; 291:1175-97. [PMID: 26507654 DOI: 10.1074/jbc.m115.691659] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Indexed: 11/06/2022] Open
Abstract
The recent classification of glycoside hydrolase family 5 (GH5) members into subfamilies enhances the prediction of substrate specificity by phylogenetic analysis. However, the small number of well characterized members is a current limitation to understanding the molecular basis of the diverse specificity observed across individual GH5 subfamilies. GH5 subfamily 4 (GH5_4) is one of the largest, with known activities comprising (carboxymethyl)cellulases, mixed-linkage endo-glucanases, and endo-xyloglucanases. Through detailed structure-function analysis, we have revisited the characterization of a classic GH5_4 carboxymethylcellulase, PbGH5A (also known as Orf4, carboxymethylcellulase, and Cel5A), from the symbiotic rumen Bacteroidetes Prevotella bryantii B14. We demonstrate that carboxymethylcellulose and phosphoric acid-swollen cellulose are in fact relatively poor substrates for PbGH5A, which instead exhibits clear primary specificity for the plant storage and cell wall polysaccharide, mixed-linkage β-glucan. Significant activity toward the plant cell wall polysaccharide xyloglucan was also observed. Determination of PbGH5A crystal structures in the apo-form and in complex with (xylo)glucan oligosaccharides and an active-site affinity label, together with detailed kinetic analysis using a variety of well defined oligosaccharide substrates, revealed the structural determinants of polysaccharide substrate specificity. In particular, this analysis highlighted the PbGH5A active-site motifs that engender predominant mixed-linkage endo-glucanase activity vis à vis predominant endo-xyloglucanases in GH5_4. However the detailed phylogenetic analysis of GH5_4 members did not delineate particular clades of enzymes sharing these sequence motifs; the phylogeny was instead dominated by bacterial taxonomy. Nonetheless, our results provide key enzyme functional and structural reference data for future bioinformatics analyses of (meta)genomes to elucidate the biology of complex gut ecosystems.
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Affiliation(s)
- Nicholas McGregor
- From the Michael Smith Laboratories and Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Mariya Morar
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5G 1L6, Canada
| | - Thomas Hauch Fenger
- From the Michael Smith Laboratories and Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Peter Stogios
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5G 1L6, Canada
| | - Nicolas Lenfant
- the Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille Université, Marseille 13288, France
| | - Victor Yin
- From the Michael Smith Laboratories and Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Xiaohui Xu
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5G 1L6, Canada
| | - Elena Evdokimova
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5G 1L6, Canada
| | - Hong Cui
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5G 1L6, Canada
| | - Bernard Henrissat
- the Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille Université, Marseille 13288, France, the Department of Biological Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia, and INRA, USC 1408 AFMB, F-13288 Marseille, France
| | - Alexei Savchenko
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5G 1L6, Canada,
| | - Harry Brumer
- From the Michael Smith Laboratories and Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada,
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36
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Petkun S, Rozman Grinberg I, Lamed R, Jindou S, Burstein T, Yaniv O, Shoham Y, Shimon LJ, Bayer EA, Frolow F. Reassembly and co-crystallization of a family 9 processive endoglucanase from its component parts: structural and functional significance of the intermodular linker. PeerJ 2015; 3:e1126. [PMID: 26401442 PMCID: PMC4579020 DOI: 10.7717/peerj.1126] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/04/2015] [Indexed: 11/22/2022] Open
Abstract
Non-cellulosomal processive endoglucanase 9I (Cel9I) from Clostridium thermocellum is a modular protein, consisting of a family-9 glycoside hydrolase (GH9) catalytic module and two family-3 carbohydrate-binding modules (CBM3c and CBM3b), separated by linker regions. GH9 does not show cellulase activity when expressed without CBM3c and CBM3b and the presence of the CBM3c was previously shown to be essential for endoglucanase activity. Physical reassociation of independently expressed GH9 and CBM3c modules (containing linker sequences) restored 60-70% of the intact Cel9I endocellulase activity. However, the mechanism responsible for recovery of activity remained unclear. In this work we independently expressed recombinant GH9 and CBM3c with and without their interconnecting linker in Escherichia coli. We crystallized and determined the molecular structure of the GH9/linker-CBM3c heterodimer at a resolution of 1.68 Å to understand the functional and structural importance of the mutual spatial orientation of the modules and the role of the interconnecting linker during their re-association. Enzyme activity assays and isothermal titration calorimetry were performed to study and compare the effect of the linker on the re-association. The results indicated that reassembly of the modules could also occur without the linker, albeit with only very low recovery of endoglucanase activity. We propose that the linker regions in the GH9/CBM3c endoglucanases are important for spatial organization and fixation of the modules into functional enzymes.
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Affiliation(s)
- Svetlana Petkun
- Department of Molecular Microbiology and Biotechnology, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv, Israel
| | - Inna Rozman Grinberg
- Department of Molecular Microbiology and Biotechnology, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv, Israel
| | - Raphael Lamed
- Department of Molecular Microbiology and Biotechnology, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv, Israel
| | - Sadanari Jindou
- Department of Life Sciences, Meijo University, Nagoya, Japan
| | - Tal Burstein
- Department of Molecular Microbiology and Biotechnology, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv, Israel
| | - Oren Yaniv
- Department of Molecular Microbiology and Biotechnology, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv, Israel
| | - Yuval Shoham
- Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Linda J.W. Shimon
- Department of Chemical Research Support, The Weizmann Institute of Science, Rehovot, Israel
| | - Edward A. Bayer
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
| | - Felix Frolow
- Department of Molecular Microbiology and Biotechnology, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv, Israel
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