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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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2
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Fu Z, Zhang F, Wang H, Tang L, Yu W, Han F. A "Pro-Asp-Thr" Amino Acid Repeat from Vibrio sp. QY108 Alginate Lyase Exhibits Alginate-Binding Capacity and Enhanced Soluble Expression and Thermostability. Int J Mol Sci 2024; 25:5801. [PMID: 38891987 PMCID: PMC11171654 DOI: 10.3390/ijms25115801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/10/2024] [Accepted: 05/16/2024] [Indexed: 06/21/2024] Open
Abstract
Alginate lyases cleave the 1,4-glycosidic bond of alginate by eliminating sugar molecules from its bond. While earlier reported alginate lyases were primarily single catalytic domains, research on multi-module alginate lyases has been lfiguimited. This study identified VsAly7A, a multi-module alginate lyase present in Vibrio sp. QY108, comprising a "Pro-Asp-Thr(PDT)" fragment and two PL-7 catalytic domains (CD I and CD II). The "PDT" fragment enhances the soluble expression level and increases the thermostability and binding affinity to the substrate. Moreover, CD I exhibited greater catalytic efficiency than CD II. The incorporation of PDT-CD I resulted in an increase in the optimal temperature of VsAly7A, whereas CD II displayed a preference for polyG degradation. The multi-domain structure of VsAly7A provides a new idea for the rational design of alginate lyase, whilst the "PDT" fragment may serve as a fusion tag in the soluble expression of recombinant proteins.
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Affiliation(s)
- Zheng Fu
- Key Laboratory of Marine Drugs (Ministry of Education), Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Fengchao Zhang
- Key Laboratory of Marine Drugs (Ministry of Education), Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Hainan Wang
- Key Laboratory of Marine Drugs (Ministry of Education), Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Luyao Tang
- Key Laboratory of Marine Drugs (Ministry of Education), Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Wengong Yu
- Key Laboratory of Marine Drugs (Ministry of Education), Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Feng Han
- Key Laboratory of Marine Drugs (Ministry of Education), Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
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3
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Monica P, Ranjan R, Kapoor M. Family 3 CBM improves the biochemical properties, substrate hydrolysis and coconut oil extraction by hemicellulolytic and holocellulolytic chimeras. Enzyme Microb Technol 2024; 174:110375. [PMID: 38157781 DOI: 10.1016/j.enzmictec.2023.110375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 11/10/2023] [Accepted: 12/07/2023] [Indexed: 01/03/2024]
Abstract
To understand the influence of family 3 Carbohydrate Binding Module (hereafter CBM3), single (GH5 cellulase; CelB, CelBΔCBM), bi-chimeric [GH26 endo-mannanase (ManB-1601) and GH11 endo-xylanase (XynB); ManB-XynB [1], ManB-XynB-CBM] and tri-chimeric [ManB-XynB-CelB [1], ManB-XynB-CelBΔCBM] enzyme variants (fused or deleted of CBM) were produced and purified to homogeneity. CBM3 did not alter the pH and temperature optima of bi- and tri-chimeric enzymes but improved the pH and temperature stability of ManB in CBM variants of bi-/tri-chimeric enzymes. Truncation of CBM in CelB shifted the pH optimum and increased the melting temperature (Tm 65 ℃). CBM3 improved both substrate affinity (Km) and catalytic efficiency (kcat/Km) of fused enzymes in tri-chimera and CelB but only Km for bi-chimera. Far-UV CD of CelB and bi- and tri-chimeric enzymes suggested that CBM3 improved the α-helical content and compactness in the native state but did not prevent disintegration of secondary structural contents at acidic pH. Steady-state fluorescence studies suggested that under acidic conditions CBM3 prevented the exposure of hydrophobic patches in bi-chimeric protein but could not avert the opening up of chimeric enzyme structure. Aqueous enzyme assisted treatment of mature coconut kernel using single, bi- and tri-chimeric enzymes led to cracks, peeling and fracturing of the matrix and improved the oil yield by up to 22%.
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Affiliation(s)
- P Monica
- Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysuru 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, UP, India
| | - Ritesh Ranjan
- Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysuru 570 020, India
| | - Mukesh Kapoor
- Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysuru 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, UP, India.
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4
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Soong YHV, Abid U, Chang AC, Ayafor C, Patel A, Qin J, Xu J, Lawton C, Wong HW, Sobkowicz MJ, Xie D. Enzyme selection, optimization, and production toward biodegradation of post-consumer poly(ethylene terephthalate) at scale. Biotechnol J 2023; 18:e2300119. [PMID: 37594123 DOI: 10.1002/biot.202300119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 08/07/2023] [Accepted: 08/11/2023] [Indexed: 08/19/2023]
Abstract
Poly(ethylene terephthalate) (PET) is one of the world's most widely used polyester plastics. Due to its chemical stability, PET is extremely difficult to hydrolyze in a natural environment. Recent discoveries in new polyester hydrolases and breakthroughs in enzyme engineering strategies have inspired enormous research on biorecycling of PET. This study summarizes our research efforts toward large-scale, efficient, and economical biodegradation of post-consumer waste PET, including PET hydrolase selection and optimization, high-yield enzyme production, and high-capacity enzymatic degradation of post-consumer waste PET. First, genes encoding PETase and MHETase from Ideonella sakaiensis and the ICCG variant of leaf-branch compost cutinase (LCCICCG ) were codon-optimized and expressed in Escherichia coli BL21(DE3) for high-yield production. To further lower the enzyme production cost, a pelB leader sequence was fused to LCCICCG so that the enzyme can be secreted into the medium to facilitate recovery. To help bind the enzyme on the hydrophobic surface of PET, a substrate-binding module in a polyhydroxyalkanoate depolymerase from Alcaligenes faecalis (PBM) was fused to the C-terminus of LCCICCG . The resulting four different LCCICCG variants (LCC, PelB-LCC, LCC-PBM, and PelB-LCC-PBM), together with PETase and MHETase, were compared for PET degradation efficiency. A fed-batch fermentation process was developed to produce the target enzymes up to 1.2 g L-1 . Finally, the best enzyme, PelB-LCC, was selected and used for the efficient degradation of 200 g L-1 recycled PET in a well-controlled, stirred-tank reactor. The results will help develop an economical and scalable biorecycling process toward a circular PET economy.
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Affiliation(s)
- Ya-Hue Valerie Soong
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Umer Abid
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Allen C Chang
- Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Christian Ayafor
- Energy Engineering Program, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Akanksha Patel
- Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Jiansong Qin
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Jin Xu
- Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Carl Lawton
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Hsi-Wu Wong
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Margaret J Sobkowicz
- Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Dongming Xie
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
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Suryawanshi PR, Badapanda C, Singh KM, Rathore A. Exploration of the rumen microbial diversity and carbohydrate active enzyme profile of black Bengal goat using metagenomic approach. Anim Biotechnol 2023; 34:761-774. [PMID: 31081473 DOI: 10.1080/10495398.2019.1609489] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Black Bengal goats possess a rich source of rumen microbiota that helps them to adapt for the better utilization of plant biomaterial into energy and nutrients, a task largely performed by enzymes encoded by the rumen microbiota. Therefore the study was designed in order to explore the taxonomic profile of rumen microbial communities and potential biomass degradation enzymes present in the rumen of back Bengal goat using Illumina Nextseq-500 platform. A total of 83.18 million high-quality reads were generated and bioinformatics analysis was performed using various tools and subsequently, the predicted ORFs along with the rRNA containing contigs were then uploaded to MG-RAST to analyze taxonomic and functional profiling. The results highlighted that Bacteriodetes (41.38-59.74%) were the most abundant phyla followed by Firmicutes (30.59-39.96%), Proteobacteria (5.07-7.61%), Euryarcheaota (0.71-7.41%), Actinobacteria (2.05-2.75%). Genes that encode glycoside hydrolases (GHs) had the highest number of CAZymes, and accounted for (39.73-37.88%) of all CAZymes in goat rumen. The GT families were the second-most abundant in CAZymes (23.73-23.11%) and followed by Carbohydrate Binding module Domain (17.65-15.61%), Carbohydrate Esterase (12.90-11.95%). This study indicated that goat rumen had complex functional microorganisms produce numerous CAZymes, and that can be further effectively utilised for applied ruminant research and industry based applications.
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Affiliation(s)
- Prashant R Suryawanshi
- Department of Veterinary Microbiology, College of Veterinary Sciences & Animal Husbandry, Agartala, India
| | | | - Krishna M Singh
- Molecular Biology Department, Unipath Specialty Laboratory Ltd., Ahmedabad, India
| | - Ankita Rathore
- Bioinformatics Division, Xcelris Labs Limited, Ahmedabad, India
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6
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An Insight into the Essential Role of Carbohydrate-Binding Modules in Enzymolysis of Xanthan. Int J Mol Sci 2023; 24:ijms24065480. [PMID: 36982553 PMCID: PMC10049358 DOI: 10.3390/ijms24065480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/16/2023] Open
Abstract
To date, due to the low accessibility of enzymes to xanthan substrates, the enzymolysis of xanthan remains deficient, which hinders the industrial production of functional oligoxanthan. To enhance the enzymatic affinity against xanthan, the essential role of two carbohydrate binding modules—MiCBMx and PspCBM84, respectively, derived from Microbacterium sp. XT11 and Paenibacillus sp. 62047—in catalytic properties of endotype xanthanase MiXen were investigated for the first time. Basic characterizations and kinetic parameters of different recombinants revealed that, compared with MiCBMx, PspCBM84 dramatically increased the thermostability of endotype xanthanase, and endowed the enzyme with higher substrate affinity and catalytic efficiency. Notably, the activity of endotype xanthanase was increased by 16 times after being fused with PspCBM84. In addition, the presence of both CBMs obviously enabled endotype xanthanase to produce more oligoxanthan, and xanthan digests prepared by MiXen-CBM84 showed better antioxidant activity due to the higher content of active oligosaccharides. The results of this work lay a foundation for the rational design of endotype xanthanase and the industrial production of oligoxanthan in the future.
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7
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On the impact of carbohydrate-binding modules (CBMs) in lytic polysaccharide monooxygenases (LPMOs). Essays Biochem 2022; 67:561-574. [PMID: 36504118 PMCID: PMC10154629 DOI: 10.1042/ebc20220162] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 11/18/2022] [Accepted: 11/21/2022] [Indexed: 12/14/2022]
Abstract
Abstract
Lytic polysaccharide monooxygenases (LPMOs) have revolutionized our understanding of how enzymes degrade insoluble polysaccharides. Compared with the substantial knowledge developed on the structure and mode of action of the catalytic LPMO domains, the (multi)modularity of LPMOs has received less attention. The presence of other domains, in particular carbohydrate-binding modules (CBMs), tethered to LPMOs has profound implications for the catalytic performance of the full-length enzymes. In the last few years, studies on LPMO modularity have led to advancements in elucidating how CBMs, other domains, and linker regions influence LPMO structure and function. This mini review summarizes recent literature, with particular focus on comparative truncation studies, to provide an overview of the diversity in LPMO modularity and the functional implications of this diversity.
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8
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Brown JL, Swift CL, Mondo SJ, Seppala S, Salamov A, Singan V, Henrissat B, Drula E, Henske JK, Lee S, LaButti K, He G, Yan M, Barry K, Grigoriev IV, O'Malley MA. Co‑cultivation of the anaerobic fungus Caecomyces churrovis with Methanobacterium bryantii enhances transcription of carbohydrate binding modules, dockerins, and pyruvate formate lyases on specific substrates. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:234. [PMID: 34893091 PMCID: PMC8665504 DOI: 10.1186/s13068-021-02083-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/19/2021] [Indexed: 05/12/2023]
Abstract
Anaerobic fungi and methanogenic archaea are two classes of microorganisms found in the rumen microbiome that metabolically interact during lignocellulose breakdown. Here, stable synthetic co-cultures of the anaerobic fungus Caecomyces churrovis and the methanogen Methanobacterium bryantii (not native to the rumen) were formed, demonstrating that microbes from different environments can be paired based on metabolic ties. Transcriptional and metabolic changes induced by methanogen co-culture were evaluated in C. churrovis across a variety of substrates to identify mechanisms that impact biomass breakdown and sugar uptake. A high-quality genome of C. churrovis was obtained and annotated, which is the first sequenced genome of a non-rhizoid-forming anaerobic fungus. C. churrovis possess an abundance of CAZymes and carbohydrate binding modules and, in agreement with previous studies of early-diverging fungal lineages, N6-methyldeoxyadenine (6mA) was associated with transcriptionally active genes. Co-culture with the methanogen increased overall transcription of CAZymes, carbohydrate binding modules, and dockerin domains in co-cultures grown on both lignocellulose and cellulose and caused upregulation of genes coding associated enzymatic machinery including carbohydrate binding modules in family 18 and dockerin domains across multiple growth substrates relative to C. churrovis monoculture. Two other fungal strains grown on a reed canary grass substrate in co-culture with the same methanogen also exhibited high log2-fold change values for upregulation of genes encoding carbohydrate binding modules in families 1 and 18. Transcriptional upregulation indicated that co-culture of the C. churrovis strain with a methanogen may enhance pyruvate formate lyase (PFL) function for growth on xylan and fructose and production of bottleneck enzymes in sugar utilization pathways, further supporting the hypothesis that co-culture with a methanogen may enhance certain fungal metabolic functions. Upregulation of CBM18 may play a role in fungal-methanogen physical associations and fungal cell wall development and remodeling.
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Affiliation(s)
- Jennifer L Brown
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Candice L Swift
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Stephen J Mondo
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Susanna Seppala
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Asaf Salamov
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Vasanth Singan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Bernard Henrissat
- DTU Bioengineering, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Elodie Drula
- Architecture Et Fonction Des Macromolécules Biologiques, CNRS/Aix-Marseille University, Marseille, France
- INRAE USC1408, AFMB, 13009, Marseille, France
| | - John K Henske
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Samantha Lee
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Kurt LaButti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Guifen He
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Mi Yan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Michelle A O'Malley
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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Thakur K, Shlain MA, Marianski M, Braunschweig AB. Regiochemical Effects on the Carbohydrate Binding and Selectivity of Flexible Synthetic Carbohydrate Receptors with Indole and Quinoline Heterocyclic Groups. European J Org Chem 2021; 2021:5262-5274. [PMID: 35694139 PMCID: PMC9186342 DOI: 10.1002/ejoc.202100763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Indexed: 08/07/2023]
Abstract
Synthetic carbohydrate receptors (SCRs) that bind cell-surface carbohydrates could be used for disease detection, drug-delivery, and therapeutics, or for the site-selective modification of complex carbohydrates but their potential has not been realized because of remaining challenges associated with binding affinity and substrate selectivity. We have reported recently a series of flexible SCRs based upon a biaryl core with four pendant heterocyclic groups that bind glycans selectively through noncovalent interactions. Here we continue to explore the role of heterocycles on substrate selectivity by expanding our library to include a series of indole and quinoline heterocycles that vary in their regiochemistry of attachment to the biaryl core. The binding of these SCRs to a series of biologically-relevant carbohydrates was studied by 1H NMR titrations in CD2Cl2 and density-functional theory calculations. We find SCR030, SCR034 and SCR037 are selective, SCR031, SCR032, and SCR039 are strong binders, and SCR033, SCR035, SCR036, and SCR038 are promiscuous and bind weakly. Computational analysis reveals the importance of C-H⋯π and H-bonding interactions in defining the binding properties of these new receptors. By combining these data with those obtained from our previous studies on this class of flexible SCRs, we develop a series of design rules that account for the binding of all SCRs of this class and anticipate the binding of future, not-yet imagined tetrapodal SCRs.
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Affiliation(s)
- Khushabu Thakur
- Nanoscience Initiative, Advanced Science Research Center at The Graduate Center of the City University of New York 85 St Nicholas Terrace, New York, NY 10031 (USA)
- Department of Chemistry and Biochemistry, Hunter College 695 Park Ave, New York, NY 10065 (USA)
| | - Milan A Shlain
- Nanoscience Initiative, Advanced Science Research Center at The Graduate Center of the City University of New York 85 St Nicholas Terrace, New York, NY 10031 (USA)
- Department of Chemistry and Biochemistry, Hunter College 695 Park Ave, New York, NY 10065 (USA)
| | - Mateusz Marianski
- Nanoscience Initiative, Advanced Science Research Center at The Graduate Center of the City University of New York 85 St Nicholas Terrace, New York, NY 10031 (USA)
- Department of Chemistry and Biochemistry, Hunter College 695 Park Ave, New York, NY 10065 (USA)
- The PhD Program in Chemistry, The Graduate Center of the City University of New York, 365 5 Ave, New York, NY 10016 (USA)
- The PhD Program in Biochemistry, The Graduate Center of the City University of New York, 365 5 Ave, New York, NY 10016 (USA)
| | - Adam B Braunschweig
- Nanoscience Initiative, Advanced Science Research Center at The Graduate Center of the City University of New York 85 St Nicholas Terrace, New York, NY 10031 (USA)
- Department of Chemistry and Biochemistry, Hunter College 695 Park Ave, New York, NY 10065 (USA)
- The PhD Program in Chemistry, The Graduate Center of the City University of New York, 365 5 Ave, New York, NY 10016 (USA)
- The PhD Program in Biochemistry, The Graduate Center of the City University of New York, 365 5 Ave, New York, NY 10016 (USA)
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10
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Sauvaitre T, Etienne-Mesmin L, Sivignon A, Mosoni P, Courtin CM, Van de Wiele T, Blanquet-Diot S. Tripartite relationship between gut microbiota, intestinal mucus and dietary fibers: towards preventive strategies against enteric infections. FEMS Microbiol Rev 2021; 45:5918835. [PMID: 33026073 DOI: 10.1093/femsre/fuaa052] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 10/05/2020] [Indexed: 02/06/2023] Open
Abstract
The human gut is inhabited by a large variety of microorganims involved in many physiological processes and collectively referred as to gut microbiota. Disrupted microbiome has been associated with negative health outcomes and especially could promote the onset of enteric infections. To sustain their growth and persistence within the human digestive tract, gut microbes and enteric pathogens rely on two main polysaccharide compartments, namely dietary fibers and mucus carbohydrates. Several evidences suggest that the three-way relationship between gut microbiota, dietary fibers and mucus layer could unravel the capacity of enteric pathogens to colonise the human digestive tract and ultimately lead to infection. The review starts by shedding light on similarities and differences between dietary fibers and mucus carbohydrates structures and functions. Next, we provide an overview of the interactions of these two components with the third partner, namely, the gut microbiota, under health and disease situations. The review will then provide insights into the relevance of using dietary fibers interventions to prevent enteric infections with a focus on gut microbial imbalance and impaired-mucus integrity. Facing the numerous challenges in studying microbiota-pathogen-dietary fiber-mucus interactions, we lastly describe the characteristics and potentialities of currently available in vitro models of the human gut.
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Affiliation(s)
- Thomas Sauvaitre
- Université Clermont Auvergne, UMR 454 INRAe, Microbiology, Digestive Environment and Health (MEDIS), Clermont-Ferrand, France.,Ghent University, Faculty of Bioscience Engineering, Center for Microbial Ecology and Technology (CMET), Ghent, Belgium
| | - Lucie Etienne-Mesmin
- Université Clermont Auvergne, UMR 454 INRAe, Microbiology, Digestive Environment and Health (MEDIS), Clermont-Ferrand, France
| | - Adeline Sivignon
- Université Clermont Auvergne, UMR 1071 Inserm, USC-INRAe 2018, Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte (M2iSH), Clermont-Ferrand, France
| | - Pascale Mosoni
- Université Clermont Auvergne, UMR 454 INRAe, Microbiology, Digestive Environment and Health (MEDIS), Clermont-Ferrand, France
| | - Christophe M Courtin
- KU Leuven, Faculty of Bioscience Engineering, Laboratory of Food Chemistry and Biochemistry & Leuven Food Science and Nutrition Research Centre (LFoRCe), Leuven, Belgium
| | - Tom Van de Wiele
- Ghent University, Faculty of Bioscience Engineering, Center for Microbial Ecology and Technology (CMET), Ghent, Belgium
| | - Stéphanie Blanquet-Diot
- Université Clermont Auvergne, UMR 454 INRAe, Microbiology, Digestive Environment and Health (MEDIS), Clermont-Ferrand, France
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11
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Furtado GP, Carli S, Meleiro LP, Salgado JCS, Ward RJ. Enhanced hydrolytic efficiency of an engineered CBM11-glucanase enzyme chimera against barley β-d-glucan extracts. Food Chem 2021; 365:130460. [PMID: 34237573 DOI: 10.1016/j.foodchem.2021.130460] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 06/01/2021] [Accepted: 06/23/2021] [Indexed: 11/25/2022]
Abstract
The β-d-glucans are abundant cell wall polysaccharides in many cereals and contain both (1,3)- and (1,4)-bonds. The β-1,3-1,4-glucanases (EC 3.2.1.73) hydrolyze β-(1,4)-d-glucosidic linkages in glucans, and have applications in both animal and human food industries. A chimera between the family 11 carbohydrate-binding module from Ruminoclostridium (Clostridium)thermocellumcelH (RtCBM11), with the β-1,3-1,4-glucanase from Bacillus subtilis (BglS) was constructed by end-to-end fusion (RtCBM11-BglS) to evaluate the effects on the catalytic function and its application in barley β-glucan degradation for the brewing industry. The parental and chimeric BglS presented the same optimum pH (6.0) and temperature (50 °C) for maximum activity. The RtCBM11-BglS showed increased thermal stability and 30% higher hydrolytic efficiency against purified barley β-glucan, and the rate of hydrolysis of β-1,3-1,4-glucan in crude barley extracts was significantly increased. The enhanced catalytic performance of the RtCBM11-BglS may be useful for the treatment of crude barley extracts in the brewing industry.
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Affiliation(s)
| | - Sibeli Carli
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida dos Bandeirantes 3900, Ribeirão Preto, São Paulo, Brazil
| | - Luana Parras Meleiro
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida dos Bandeirantes 3900, Ribeirão Preto, São Paulo, Brazil
| | - José Carlos Santos Salgado
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida dos Bandeirantes 3900, Ribeirão Preto, São Paulo, Brazil
| | - Richard John Ward
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida dos Bandeirantes 3900, Ribeirão Preto, São Paulo, Brazil.
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12
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An insight into transcriptome of Cyathus bulleri for lignocellulase expression on wheat bran. Arch Microbiol 2021; 203:3727-3736. [PMID: 33877388 DOI: 10.1007/s00203-021-02326-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 04/06/2021] [Accepted: 04/09/2021] [Indexed: 10/21/2022]
Abstract
To identify enzymes that can be effectively used for hydrolysis of lignocellulosic biomass, an attractive carbon source in biorefineries, transcriptome analysis was carried out of wheat bran grown fungus, Cyathus bulleri. A comprehensive set of transcripts, encoding carbohydrate active enzymes, were identified. These belonged to 55, 32, 12, 11 and 7 different families of the enzyme classes of Glycoside Hydrolases (GHs), Glycosyl Transferases (GTs), Auxiliary Activities (AAs), Carbohydrate Esterases (CEs) and Polysaccharide Lyases (PLs) respectively. Higher levels of transcripts were obtained for proteins encoding cellulose and hemicellulose degrading activities (of the GH class) with the highest diversity found in the transcripts encoding the hemicellulases. Several transcripts encoding pectin degrading activity were also identified indicating close association of the pectin with the cellulose/hemicellulose in the cell wall of this fungus. Transcripts encoding ligninases were categorized into Cu radical oxidase, Glucose-Methanol-Choline oxidoreductase (with 37 different transcripts in the AA3 sub-family), Laccase and Manganese peroxidases. Temporal gene expression profile for laccase isoforms was studied to understand their role in lignin degradation. To our knowledge, this is the first analysis of the transcriptome of a member belonging to the family Nidulariaceae.
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13
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Rai A, Bhattacharjee A. Molecular profiling of microbial community structure and their CAZymes via metagenomics, from Tsomgo lake in the Eastern Himalayas. Arch Microbiol 2021; 203:3135-3146. [PMID: 33813595 DOI: 10.1007/s00203-021-02278-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 03/09/2021] [Accepted: 03/11/2021] [Indexed: 02/01/2023]
Abstract
The present study is the first of its kind which is focused on Tsomgo lake, a high-altitude lake, located in the Eastern Himalayas of Sikkim. To get a major insight into the bacterial diversity, the shotgun sequencing was carried out in Illumina platform. Our results showed that both the samples TLSS1 (soil) and TLSW1 (water), had Proteobacteria as the most abundant taxa. Cluster of Orthologous group (COG) functional category of TLSS1 has 1,46,965 predicted functions. Cluster of Orthologous Group (COG) functional category of TLSW1 has 1,34,773 predicted functions. Kyoto Encyclopedia of Gene and Genomes (KEGG) functional category of TLSS1 has 1,76,825 predicted functions, most of the sequence fall in metabolism followed by Environmental information processing function. (KEGG) functional category of TLSW1 has 1,62,696 predicted functions and it follows the same pattern as TLSS1. Our studies also provide insight into the presence of distribution of different carbohydrate-active enzymes (CAZymes) present in Tsomgo lake. We have found that in case of both the samples TLSW1 and TLSS1, GlycosylTransferases were active followed by GlycosylHydrolase. The result found, represents for the first time very important findings related to the microbial diversity and the abundance of CAZymes in Tsomgo lake one of the pristine high-altitude lakes in Sikkim.
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Affiliation(s)
- Aditi Rai
- Department of Microbiology, University of North Bengal, Darjeeling, 734013, West Bengal, India
| | - Arindam Bhattacharjee
- Department of Microbiology, University of North Bengal, Darjeeling, 734013, West Bengal, India.
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14
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Zhang H, Wang Y, Brunecky R, Yao B, Xie X, Zheng F, Luo H. A Swollenin From Talaromyces leycettanus JCM12802 Enhances Cellulase Hydrolysis Toward Various Substrates. Front Microbiol 2021; 12:658096. [PMID: 33854492 PMCID: PMC8039133 DOI: 10.3389/fmicb.2021.658096] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 03/10/2021] [Indexed: 12/02/2022] Open
Abstract
Swollenins exist within some fungal species and are candidate accessory proteins for the biodegradation of cellulosic substrates. Here, we describe the identification of a swollenin gene, Tlswo, in Talaromyces leycettanus JCM12802. Tlswo was successfully expressed in both Trichoderma reesei and Pichia pastoris. Assay results indicate that TlSWO is capable of releasing reducing sugars from lichenan, barley β-glucan, carboxymethyl cellulose sodium (CMC-Na) and laminarin. The specific activity of TlSWO toward lichenan, barley β-glucan, carboxymethyl cellulose sodium (CMC-Na) and laminarin is 9.0 ± 0.100, 8.9 ± 0.100, 2.3 ± 0.002 and 0.79 ± 0.002 U/mg, respectively. Additionally, TlSWO had disruptive activity on Avicel and a synergistic effect with cellobiohydrolases, increasing the activity on pretreated corn stover by up to 72.2%. The functional diversity of TlSWO broadens its applicability in experimental settings, and indicating that it may be a promising candidate for future industrial applications.
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Affiliation(s)
- Honghai Zhang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuan Wang
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Roman Brunecky
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, United States
| | - Bin Yao
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiangming Xie
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Fei Zheng
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Huiying Luo
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
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15
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New Family of Carbohydrate-Binding Modules Defined by a Galactosyl-Binding Protein Module from a Cellvibrio japonicus Endo-Xyloglucanase. Appl Environ Microbiol 2021; 87:e0263420. [PMID: 33355108 DOI: 10.1128/aem.02634-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Carbohydrate-binding modules (CBMs) are usually appended to carbohydrate-active enzymes (CAZymes) and serve to potentiate catalytic activity, for example, by increasing substrate affinity. The Gram-negative soil saprophyte Cellvibrio japonicus is a valuable source for CAZyme and CBM discovery and characterization due to its innate ability to degrade a wide array of plant polysaccharides. Bioinformatic analysis of the CJA_2959 gene product from C. japonicus revealed a modular architecture consisting of a fibronectin type III (Fn3) module, a cryptic module of unknown function (X181), and a glycoside hydrolase family 5 subfamily 4 (GH5_4) catalytic module. We previously demonstrated that the last of these, CjGH5F, is an efficient and specific endo-xyloglucanase (M. A. Attia, C. E. Nelson, W. A. Offen, N. Jain, et al., Biotechnol Biofuels 11:45, 2018, https://doi.org/10.1186/s13068-018-1039-6). In the present study, C-terminal fusion of superfolder green fluorescent protein in tandem with the Fn3-X181 modules enabled recombinant production and purification from Escherichia coli. Native affinity gel electrophoresis revealed binding specificity for the terminal galactose-containing plant polysaccharides galactoxyloglucan and galactomannan. Isothermal titration calorimetry further evidenced a preference for galactoxyloglucan polysaccharide over short oligosaccharides comprising the limit-digest products of CjGH5F. Thus, our results identify the X181 module as the defining member of a new CBM family, CBM88. In addition to directly revealing the function of this CBM in the context of xyloglucan metabolism by C. japonicus, this study will guide future bioinformatic and functional analyses across microbial (meta)genomes. IMPORTANCE This study reveals carbohydrate-binding module family 88 (CBM88) as a new family of galactose-binding protein modules, which are found in series with diverse microbial glycoside hydrolases, polysaccharide lyases, and carbohydrate esterases. The definition of CBM88 in the carbohydrate-active enzymes classification (http://www.cazy.org/CBM88.html) will significantly enable future microbial (meta)genome analysis and functional studies.
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16
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Ji Y, Lu Y, Puetz H, Schwaneberg U. Anchor peptides promote degradation of mixed plastics for recycling. Methods Enzymol 2021; 648:271-292. [PMID: 33579408 DOI: 10.1016/bs.mie.2020.12.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Resource stewardship and sustainable use of natural resources is mandatory for a circular plastic economy. The discovery of microbes and enzymes that can selectively degrade mixed-plastic waste enables to recycle plastics. Knowledge on how to achieve efficient and selective enzymatic plastic degradation is a key prerequisite for biocatalytic recycling of plastics. Wild-type natural polymer degrading enzymes such as cellulases pose often selective non-catalytic binding domains that facilitate a targeting and efficient degradation of polymeric substrates. Recently identified polyester hydrolases with synthetic polymer degrading activities, however, lack in general such selective domains. Inspired by nature, we herein report a protocol for the identification and engineering of anchor peptides which serve as non-catalytic binding domains specifically toward synthetic plastics. The identified anchor peptides hold the promise to be fused to known plastic degrading enzymes and thereby enhance the efficiency of biocatalytic plastic recycling processes.
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Affiliation(s)
- Yu Ji
- Institute of Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Yi Lu
- Institute of Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Hendrik Puetz
- Institute of Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Ulrich Schwaneberg
- Institute of Biotechnology, RWTH Aachen University, Aachen, Germany; DWI-Leibniz Institute for Interactive Materials, Aachen, Germany.
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17
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Multimodularity of a GH10 Xylanase Found in the Termite Gut Metagenome. Appl Environ Microbiol 2021; 87:AEM.01714-20. [PMID: 33187992 PMCID: PMC7848910 DOI: 10.1128/aem.01714-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 11/03/2020] [Indexed: 01/01/2023] Open
Abstract
Xylan is the major hemicellulosic polysaccharide in cereals and contributes to the recalcitrance of the plant cell wall toward degradation. Bacteroidetes, one of the main phyla in rumen and human gut microbiota, have been shown to encode polysaccharide utilization loci dedicated to the degradation of xylan. Here, we present the biochemical characterization of a xylanase encoded by a bacteroidetes strain isolated from the termite gut metagenome. The functional screening of a Pseudacanthotermes militaris termite gut metagenomic library revealed an array of xylan-degrading enzymes, including P. militaris 25 (Pm25), a multimodular glycoside hydrolase family 10 (GH10). Sequence analysis showed details of the unusual domain organization of this enzyme. It consists of one catalytic domain, which is intercalated by two carbohydrate binding modules (CBMs) from family 4. The genes upstream of the genes encoding Pm25 are susC-susD-unk, suggesting Pm25 is a Xyn10C-like enzyme belonging to a polysaccharide utilization locus. The majority of Xyn10C-like enzymes shared the same interrupted domain architecture and were vastly distributed in different xylan utilization loci found in gut Bacteroidetes, indicating the importance of this enzyme in glycan acquisition for gut microbiota. To understand its unusual multimodularity and the possible role of the CBMs, a detailed characterization of the full-length Pm25 and truncated variants was performed. Results revealed that the GH10 catalytic module is specific toward the hydrolysis of xylan. Ligand binding results indicate that the GH10 module and the CBMs act independently, whereas the tandem CBM4s act synergistically with each other and improve enzymatic activity when assayed on insoluble polysaccharides. In addition, we show that the UNK protein upstream of Pm25 is able to bind arabinoxylan. Altogether, these findings contribute to a better understanding of the potential role of Xyn10C-like proteins in xylan utilization systems of gut bacteria. IMPORTANCE Xylan is the major hemicellulosic polysaccharide in cereals and contributes to the recalcitrance of the plant cell wall toward degradation. Members of the Bacteroidetes, one of the main phyla in rumen and human gut microbiota, have been shown to encode polysaccharide utilization loci dedicated to the degradation of xylan. Here, we present the biochemical characterization of a xylanase encoded by a Bacteroidetes strain isolated from the termite gut metagenome. This xylanase is a multimodular enzyme, the sequence of which is interrupted by the insertion of two CBMs from family 4. Our results show that this enzyme resembles homologues that were shown to be important for xylan degradation in rumen or human diet and show that the CBM insertion in the middle of the sequence seems to be a common feature in xylan utilization systems. This study shed light on our understanding of xylan degradation and plant cell wall deconstruction, which can be applied to several applications in food, feed, and bioeconomy.
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18
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Abstract
Cellulosomes are elaborate multienzyme complexes capable of efficiently deconstructing lignocellulosic substrates, produced by cellulolytic anaerobic microorganisms, colonizing a large variety of ecological niches. These macromolecular structures have a modular architecture and are composed of two main elements: the cohesin-bearing scaffoldins, which are non-catalytic structural proteins, and the various dockerin-bearing enzymes that tenaciously bind to the scaffoldins. Cellulosome assembly is mediated by strong and highly specific interactions between the cohesin modules, present in the scaffoldins, and the dockerin modules, present in the catalytic units. Cellulosomal architecture and composition varies between species and can even change within the same organism. These differences seem to be largely influenced by external factors, including the nature of the available carbon-source. Even though cellulosome producing organisms are relatively few, the development of new genomic and proteomic technologies has allowed the identification of cellulosomal components in many archea, bacteria and even some primitive eukaryotes. This reflects the importance of this cellulolytic strategy and suggests that cohesin-dockerin interactions could be involved in other non-cellulolytic processes. Due to their building-block nature and highly cellulolytic capabilities, cellulosomes hold many potential biotechnological applications, such as the conversion of lignocellulosic biomass in the production of biofuels or the development of affinity based technologies.
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Affiliation(s)
- Victor D Alves
- CIISA, Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477, Lisbon, Portugal
| | - Carlos M G A Fontes
- CIISA, Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477, Lisbon, Portugal
| | - Pedro Bule
- CIISA, Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477, Lisbon, Portugal.
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19
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Guerrero EB, de Villegas RMD, Soria MA, Santangelo MP, Campos E, Talia PM. Characterization of two GH5 endoglucanases from termite microbiome using synthetic metagenomics. Appl Microbiol Biotechnol 2020; 104:8351-8366. [DOI: 10.1007/s00253-020-10831-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/05/2020] [Accepted: 08/11/2020] [Indexed: 02/07/2023]
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20
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Enhanced Thermostability and Enzymatic Activity of Cel6A Variants from Thermobifida fusca by Empirical Domain Engineering (Short Title: Domain Engineering of Cel6A). BIOLOGY 2020; 9:biology9080214. [PMID: 32784797 PMCID: PMC7464639 DOI: 10.3390/biology9080214] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/29/2020] [Accepted: 08/02/2020] [Indexed: 02/07/2023]
Abstract
Cellulases are a set of lignocellulolytic enzymes, capable of producing eco-friendly low-cost renewable bioethanol. However, low stability and hydrolytic activity limit their wide-scale applicability at the industrial scale. In this work, we report the domain engineering of endoglucanase (Cel6A) of Thermobifida fusca to improve their catalytic activity and thermal stability. Later, enzymatic activity and thermostability of the most efficient variant named as Cel6A.CBC was analyzed by molecular dynamics simulations. This variant demonstrated profound activity against soluble and insoluble cellulosic substrates like filter paper, alkali-treated bagasse, regenerated amorphous cellulose (RAC), and bacterial microcrystalline cellulose. The variant Cel6A.CBC showed the highest catalysis of carboxymethyl cellulose (CMC) and other related insoluble substrates at a pH of 6.0 and a temperature of 60 °C. Furthermore, a sound rationale was observed between experimental findings and molecular modeling of Cel6A.CBC which revealed thermostability of Cel6A.CBC at 26.85, 60.85, and 74.85 °C as well as structural flexibility at 126.85 °C. Therefore, a thermostable derivative of Cel6A engineered in the present work has enhanced biological performance and can be a useful construct for the mass production of bioethanol from plant biomass.
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21
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Madland E, Crasson O, Vandevenne M, Sørlie M, Aachmann FL. NMR and Fluorescence Spectroscopies Reveal the Preorganized Binding Site in Family 14 Carbohydrate-Binding Module from Human Chitotriosidase. ACS OMEGA 2019; 4:21975-21984. [PMID: 31891077 PMCID: PMC6933781 DOI: 10.1021/acsomega.9b03043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 11/26/2019] [Indexed: 05/02/2023]
Abstract
Carbohydrate-binding modules (CBM) play important roles in targeting and increasing the concentration of carbohydrate active enzymes on their substrates. Using NMR to get the solution structure of CBM14, we can gain insight into secondary structure elements and intramolecular interactions with our assigned nuclear overhauser effect peaks. This reveals that two conserved aromatic residues (Phe437 and Phe456) make up the hydrophobic core of the CBM. These residues are also responsible for connecting the two β-sheets together, by being part of β2 and β4, respectively, and together with disulfide bridges, they create CBM14's characteristic "hevein-like" fold. Most CBMs rely on aromatic residues for substrate binding; however, CBM14 contains just a single tryptophan (Trp465) that together with Asn466 enables substrate binding. Interestingly, an alanine mutation of a single residue (Leu454) located behind Trp465 renders the CBM incapable of binding. Fluorescence spectroscopy performed on this mutant reveals a significant blue shift, as well as a minor blue shift for its neighbor Val455. The reduction in steric hindrance causes the tryptophan to be buried into the hydrophobic core of the structure and therefore suggests a preorganized binding site for this CBM. Our results show that both Trp465 and Asn466 are affected when CBM14 interacts with both (GlcNAc)3 and β-chitin, that the binding interactions are weak, and that CBM14 displays a slightly higher affinity toward β-chitin.
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Affiliation(s)
- Eva Madland
- Department
of Biotechnology and Food Science, Norwegian Biopolymer Laboratory
(NOBIPOL), NTNU Norwegian University of
Science and Technology, Trondheim 7491, Norway
| | - Oscar Crasson
- InBioS—Center
for Protein Engineering, Institut de Chimie B6a, Université de Liège, Sart-Tilman, Liège 4000, Belgium
| | - Maryléne Vandevenne
- InBioS—Center
for Protein Engineering, Institut de Chimie B6a, Université de Liège, Sart-Tilman, Liège 4000, Belgium
| | - Morten Sørlie
- Department
of Chemistry, Biotechnology and Food Science, NMBU Norwegian University of Life Sciences, Ås 1430, Norway
| | - Finn L. Aachmann
- Department
of Biotechnology and Food Science, Norwegian Biopolymer Laboratory
(NOBIPOL), NTNU Norwegian University of
Science and Technology, Trondheim 7491, Norway
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22
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Krishnan B, Srivastava SS, Sankeshi V, Garg R, Srivastava S, Sankaranarayanan R, Sharma Y. βγ-Crystallination Endows a Novel Bacterial Glycoside Hydrolase 64 with Ca 2+-Dependent Activity Modulation. J Bacteriol 2019; 201:e00392-19. [PMID: 31527113 PMCID: PMC6832075 DOI: 10.1128/jb.00392-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 09/05/2019] [Indexed: 01/10/2023] Open
Abstract
The prokaryotic βγ-crystallins are a large group of uncharacterized domains with Ca2+-binding motifs. We have observed that a vast number of these domains are found appended to other domains, in particular, the carbohydrate-active enzyme (CAZy) domains. To elucidate the functional significance of these prospective Ca2+ sensors in bacteria and this widespread domain association, we have studied one typical example from Clostridium beijerinckii, a bacterium known for its ability to produce acetone, butanol, and ethanol through fermentation of several carbohydrates. This novel glycoside hydrolase of family 64 (GH64), which we named glucanallin, is composed of a βγ-crystallin domain, a GH64 domain, and a carbohydrate-binding module 56 (CBM56). The substrates of GH64, β-1,3-glucans, are the targets for industrial biofuel production due to their plenitude. We have examined the Ca2+-binding properties of this protein, assayed its enzymatic activity, and analyzed the structural features of the β-1,3-glucanase domain through its high-resolution crystal structure. The reaction products resulting from the enzyme reaction of glucanallin reinforce the mixed nature of GH64 enzymes, in contrast to the prevailing notion of them being an exotype. Upon disabling Ca2+ binding and comparing different domain combinations, we demonstrate that the βγ-crystallin domain in glucanallin acts as a Ca2+ sensor and enhances the glycolytic activity of glucanallin through Ca2+ binding. We also compare the structural peculiarities of this new member of the GH64 family to two previously studied members.IMPORTANCE We have biochemically and structurally characterized a novel glucanase from the less studied GH64 family in a bacterium significant for fermentation of carbohydrates into biofuels. This enzyme displays a peculiar property of being distally modulated by Ca2+ via assistance from a neighboring βγ-crystallin domain, likely through changes in the domain interface. In addition, this enzyme is found to be optimized for functioning in an acidic environment, which is in line with the possibility of its involvement in biofuel production. Multiple occurrences of a similar domain architecture suggest that such a "βγ-crystallination"-mediated Ca2+ sensitivity may be widespread among bacterial proteins.
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Affiliation(s)
- Bal Krishnan
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
- Indian Institute of Science Education and Research Berhampur, Odisha, India
| | | | - Venu Sankeshi
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Rupsi Garg
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | | | - Yogendra Sharma
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
- Indian Institute of Science Education and Research Berhampur, Odisha, India
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23
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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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24
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Badur AH, Ammar EM, Yalamanchili G, Hehemann JH, Rao CV. Characterization of the GH16 and GH17 laminarinases from Vibrio breoganii 1C10. Appl Microbiol Biotechnol 2019; 104:161-171. [PMID: 31754764 DOI: 10.1007/s00253-019-10243-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/28/2019] [Accepted: 11/04/2019] [Indexed: 10/25/2022]
Abstract
Laminarin is an abundant glucose polymer used as an energy reserve by micro- and macroalgae. Bacteria digest and consume laminarin with laminarinases. Their genomes frequently contain multiple homologs; however, the biological role for this replication remains unclear. We investigated the four laminarinases of glycoside hydrolase families GH16 and GH17 from the marine bacterium Vibrio breoganii 1C10, which can use laminarin as its sole carbon source. All four laminarinases employ an endolytic mechanism and specifically cleave the β-1,3-glycosidic bond. Two primarily produce low-molecular weight laminarin oligomers (DP 3-4) whereas the others primarily produce high-molecular weight oligomers (DP > 8), which suggests that these enzymes sequentially degrade laminarin. The results from this work provide an overview of the laminarinases from a single marine bacterium and also provide insights regarding how multiple laminarinases are used to degrade laminarin.
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Affiliation(s)
- Ahmet H Badur
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL, 61801, USA
| | - Ehab M Ammar
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL, 61801, USA.,Genetic Engineering and Biotechnology Research Institute, University of Sadat City, El Sadat City, Egypt
| | - Geethika Yalamanchili
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL, 61801, USA
| | - Jan-Hendrik Hehemann
- MARUM MPG Bridge Group Marine Glycobiology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Christopher V Rao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave, Urbana, IL, 61801, USA.
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25
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Gonzalez-Delgado LS, Walters-Morgan H, Salamaga B, Robertson AJ, Hounslow AM, Jagielska E, Sabała I, Williamson MP, Lovering AL, Mesnage S. Two-site recognition of Staphylococcus aureus peptidoglycan by lysostaphin SH3b. Nat Chem Biol 2019; 16:24-30. [PMID: 31686030 PMCID: PMC6920042 DOI: 10.1038/s41589-019-0393-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/21/2019] [Indexed: 11/09/2022]
Abstract
Lysostaphin is a bacteriolytic enzyme targeting peptidoglycan, the essential component of the bacterial cell envelope. It displays a very potent and specific activity toward staphylococci, including methicillin-resistant Staphylococcus aureus. Lysostaphin causes rapid cell lysis and disrupts biofilms, and is therefore a therapeutic agent of choice to eradicate staphylococcal infections. The C-terminal SH3b domain of lysostaphin recognizes peptidoglycans containing a pentaglycine crossbridge and has been proposed to drive the preferential digestion of staphylococcal cell walls. Here we elucidate the molecular mechanism underpinning recognition of staphylococcal peptidoglycan by the lysostaphin SH3b domain. We show that the pentaglycine crossbridge and the peptide stem are recognized by two independent binding sites located on opposite sides of the SH3b domain, thereby inducing a clustering of SH3b domains. We propose that this unusual binding mechanism allows synergistic and structurally dynamic recognition of S. aureus peptidoglycan and underpins the potent bacteriolytic activity of this enzyme.
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Affiliation(s)
- Luz S Gonzalez-Delgado
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK.,Krebs Institute, University of Sheffield, Sheffield, UK
| | - Hannah Walters-Morgan
- Institute of Microbiology and Infection, and School of Biosciences, University of Birmingham, Birmingham, UK
| | - Bartłomiej Salamaga
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK.,Krebs Institute, University of Sheffield, Sheffield, UK
| | - Angus J Robertson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK.,Krebs Institute, University of Sheffield, Sheffield, UK
| | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK.,Krebs Institute, University of Sheffield, Sheffield, UK
| | | | - Izabela Sabała
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Mike P Williamson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK. .,Krebs Institute, University of Sheffield, Sheffield, UK.
| | - Andrew L Lovering
- Institute of Microbiology and Infection, and School of Biosciences, University of Birmingham, Birmingham, UK.
| | - Stéphane Mesnage
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK. .,Krebs Institute, University of Sheffield, Sheffield, UK.
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26
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Wang R, Xu D. Molecular dynamics investigations of oligosaccharides recognized by family 16 and 22 carbohydrate binding modules. Phys Chem Chem Phys 2019; 21:21485-21496. [PMID: 31535114 DOI: 10.1039/c9cp04673a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
As a non-catalytic domain, carbohydrate binding modules (CBMs) are often considered to play some key roles in the degradation and recognition of polysaccharides catalyzed by cellulases. In this work, we investigated the recognition dynamics of cello- or xylo-saccharides by two typical CBMs (CBM16-1 and CBM22-2), which are grouped into Type B CBMs. By combining extensive molecular dynamics, principle component analysis, and binding free energy calculations, we constructed several complex models of the two CBMs in both complex cello- and xylo-oligosaccharides. The corresponding substrate recognition affinity and critical residues having significant contributions were systematically investigated. The residues containing aromatic side chain groups were shown to contribute significantly to substrate binding. The calculated binding free energies were in fairly good agreement with the experimental measurements with the absolute mean error of 0.69 kcal mol-1. The overall electrostatic interactions were shown to have negative effects on substrate recognition. Further metadynamics simulations revealed the substrate dissociation process.
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Affiliation(s)
- Ruihan Wang
- MOE Key Laboratory of Green Chemistry and Technology, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China.
| | - Dingguo Xu
- MOE Key Laboratory of Green Chemistry and Technology, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China. and Research Center for Materials Genome Engineering, Sichuan University, Chengdu, Sichuan 610065, P. R. China
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27
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Bishnoi R, Mahajan S, Ramya TNC. An F-type lectin domain directs the activity of Streptosporangium roseum alpha-l-fucosidase. Glycobiology 2019; 28:860-875. [PMID: 30169639 DOI: 10.1093/glycob/cwy079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 08/29/2018] [Indexed: 11/13/2022] Open
Abstract
F-type lectins are phylogenetically widespread but selectively distributed fucose-binding lectins with L-fucose- and calcium-binding sequence motifs and an F-type lectin fold. Bacterial F-type lectin domains frequently occur in tandem with various protein domains in diverse architectures, indicating a possible role in directing enzyme activities or other biological functions to distinct fucosylated niches. Here, we report the biochemical characterization of a Streptosporangium roseum protein containing an F-type lectin domain in tandem with an NPCBM-associated domain and a family GH 29A alpha-l-fucosidase domain. We show that the F-type lectin domain of this protein recognizes fucosylated glycans in both α and β linkages but has high affinity for a Fuc-α-1,2-Gal motif and that the alpha-l-fucosidase domain displays hydrolytic activity on glycan substrates with α1-2 and α1-4 linked fucose. We also show that the F-type lectin domain does not have any effect on the activity of the cis-positioned alpha-l-fucosidase domain with the synthetic substrate, 4-Methylumbelliferyl-alpha-l-fucopyranoside or on inhibition of this activity by l-fucose or deoxyfuconojirimycin hydrochloride. However, the F-type lectin domain together with the NPCBM-associated domain enhances the activity of the cis-positioned alpha-l-fucosidase domain for soluble fucosylated oligosaccharide substrates. While there are many reports of glycoside hydrolase activity towards insoluble and soluble polysaccharides being enhanced by cis-positioned carbohydrate binding modules on the polypeptide, this is the first report, to our knowledge, of enhancement of activity towards aqueous, freely diffusible, small oligosaccharides. We propose a model involving structural stabilization and a bind-and-jump action mediated by the F-type lectin domain to rationalize our findings.
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Affiliation(s)
- Ritika Bishnoi
- Institute of Microbial Technology, Sector 39-A, Chandigarh, India
| | - Sonal Mahajan
- Institute of Microbial Technology, Sector 39-A, Chandigarh, India
| | - T N C Ramya
- Institute of Microbial Technology, Sector 39-A, Chandigarh, India
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28
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Islam S, Apitius L, Jakob F, Schwaneberg U. Targeting microplastic particles in the void of diluted suspensions. ENVIRONMENT INTERNATIONAL 2019; 123:428-435. [PMID: 30622067 DOI: 10.1016/j.envint.2018.12.029] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 12/10/2018] [Accepted: 12/13/2018] [Indexed: 05/22/2023]
Abstract
Accumulation of microplastic in the environment and food chain will be a grand challenge for our society. Polyurethanes are widely used synthetic polymers in medical (e.g. catheters) and industrial products (especially as foams). Polyurethane is not abundant in nature and only a few microbial strains (fungi and bacteria) and enzymes (polyurethaneases and cutinases) have been reported to efficiently degrade polyurethane. Notably, in nature a long period of time (from 50 to >100 years depending on the literature) is required for degradation of plastics. Material binding peptides (e.g. anchor peptides) bind strongly to polymers such as polypropylene, polyethylene terephthalate, and polyurethane and can target specifically polymers. In this study we report the fusion of the anchor peptide Tachystatin A2 to the bacterial cutinase Tcur1278 which accelerated the degradation of polyester-polyurethane nanoparticles by a factor of 6.6 in comparison to wild-type Tcur1278. Additionally, degradation half-lives of polyester-polyurethane nanoparticles were reduced from 41.8 h to 6.2 h (6.7-fold) in a diluted polyester-polyurethane suspension (0.04% w/v).
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Affiliation(s)
- Shohana Islam
- DWI - Leibniz-Institut für Interaktive Materialien e.V., Forckenbeckstraße 50, 52056 Aachen, Germany; Lehrstuhl für Biotechnologie, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany.
| | - Lina Apitius
- DWI - Leibniz-Institut für Interaktive Materialien e.V., Forckenbeckstraße 50, 52056 Aachen, Germany; Lehrstuhl für Biotechnologie, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany.
| | - Felix Jakob
- DWI - Leibniz-Institut für Interaktive Materialien e.V., Forckenbeckstraße 50, 52056 Aachen, Germany; Lehrstuhl für Biotechnologie, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany.
| | - Ulrich Schwaneberg
- DWI - Leibniz-Institut für Interaktive Materialien e.V., Forckenbeckstraße 50, 52056 Aachen, Germany; Lehrstuhl für Biotechnologie, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany.
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29
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Kognole AA, Payne CM. Cellulose-specific Type B carbohydrate binding modules: understanding oligomeric and non-crystalline substrate recognition mechanisms. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:319. [PMID: 30519283 PMCID: PMC6267901 DOI: 10.1186/s13068-018-1321-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Accepted: 11/22/2018] [Indexed: 05/29/2023]
Abstract
BACKGROUND Effective enzymatic degradation of crystalline polysaccharides requires a synergistic cocktail of hydrolytic enzymes tailored to the wide-ranging degree of substrate crystallinity. To accomplish this type of targeted carbohydrate recognition, nature produces multi-modular enzymes, having at least one catalytic domain appended to one or more carbohydrate binding modules (CBMs). The Type B CBM categorization encompasses several families (i.e., protein folds) of CBMs that are generally thought to selectively bind oligomeric polysaccharides; however, a subset of cellulose-specific CBM families (17 and 28) appear to bind non-crystalline cellulose more tightly than oligomers and in a manner that discriminates between surface topology. RESULTS To provide insight into this unexplained phenomenon, we investigated the molecular-level origins of oligomeric and non-crystalline carbohydrate recognition in cellulose-specific Type B CBMs using molecular dynamics (MD) simulation and free energy calculations. Examining two CBMs from three different families (4, 17, and 28), we describe how protein-ligand dynamics contribute to observed variations in binding affinity of oligomers within the same CBM family. Comparisons across the three CBM families identified factors leading to modified functionality prohibiting competitive binding, despite similarity in sequence and specificity. Using free energy perturbation with Hamiltonian replica exchange MD, we also examined the hypothesis that the open topology of the binding grooves in families 17 and 28 necessitates tight binding of an oligomer, while the more confined family 4 binding groove does not require the same degree of tight binding. Finally, we elucidated the mechanisms of non-crystalline carbohydrate recognition by modeling CBMs complexed with a partially decrystallized cellulose substrate. Molecular simulation provided structural and dynamic data for direct comparison to oligomeric modes of carbohydrate recognition, and umbrella sampling MD was used to determine ligand binding free energy. Comparing both protein-carbohydrate interactions and ligand binding free energies, which were in good agreement with experimental values, we confirmed the hypothesis that family 17 and 28 CBMs bind non-crystalline cellulose and oligomers with different affinities (i.e., high and low). CONCLUSIONS Our study provides an unprecedented level of insight into the complex solid and soluble carbohydrate substrate recognition mechanisms of Type B CBMs, the findings of which hold considerable promise for enhancing lignocellulosic biomass conversion technology and development of plant cell wall probes.
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Affiliation(s)
- Abhishek A. Kognole
- Department of Chemical and Materials Engineering, University of Kentucky, 177 F Paul Anderson Tower, Lexington, KY 40506 USA
| | - Christina M. Payne
- Department of Chemical and Materials Engineering, University of Kentucky, 177 F Paul Anderson Tower, Lexington, KY 40506 USA
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30
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Meier KK, Jones SM, Kaper T, Hansson H, Koetsier MJ, Karkehabadi S, Solomon EI, Sandgren M, Kelemen B. Oxygen Activation by Cu LPMOs in Recalcitrant Carbohydrate Polysaccharide Conversion to Monomer Sugars. Chem Rev 2018; 118:2593-2635. [PMID: 29155571 PMCID: PMC5982588 DOI: 10.1021/acs.chemrev.7b00421] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Natural carbohydrate polymers such as starch, cellulose, and chitin provide renewable alternatives to fossil fuels as a source for fuels and materials. As such, there is considerable interest in their conversion for industrial purposes, which is evidenced by the established and emerging markets for products derived from these natural polymers. In many cases, this is achieved via industrial processes that use enzymes to break down carbohydrates to monomer sugars. One of the major challenges facing large-scale industrial applications utilizing natural carbohydrate polymers is rooted in the fact that naturally occurring forms of starch, cellulose, and chitin can have tightly packed organizations of polymer chains with low hydration levels, giving rise to crystalline structures that are highly recalcitrant to enzymatic degradation. The topic of this review is oxidative cleavage of carbohydrate polymers by lytic polysaccharide mono-oxygenases (LPMOs). LPMOs are copper-dependent enzymes (EC 1.14.99.53-56) that, with glycoside hydrolases, participate in the degradation of recalcitrant carbohydrate polymers. Their activity and structural underpinnings provide insights into biological mechanisms of polysaccharide degradation.
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Affiliation(s)
- Katlyn K. Meier
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Stephen M. Jones
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Thijs Kaper
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, California 94304, United States
| | - Henrik Hansson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Martijn J. Koetsier
- DuPont Industrial Biosciences, Netherlands, Nieuwe Kanaal 7-S, 6709 PA Wageningen, The Netherlands
| | - Saeid Karkehabadi
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Edward I. Solomon
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, SE-750 07 Uppsala, Sweden
| | - Bradley Kelemen
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, California 94304, United States
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31
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Enhanced features of Dictyoglomus turgidum Cellulase A engineered with carbohydrate binding module 11 from Clostridium thermocellum. Sci Rep 2018. [PMID: 29535356 PMCID: PMC5849603 DOI: 10.1038/s41598-018-22769-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Lignocellulosic biomass (LCB) is a low-cost and abundant source of fermentable sugars. Enzymatic hydrolysis is one of the main ways to obtain sugars from biomass, but most of the polysaccharide-degrading enzymes are poorly efficient on LCB and cellulases with higher performances are required. In this study, we designed a chimeric protein by adding the carbohydrate binding module (CBM) of the cellulosomal enzyme CtLic26A-Cel5E (endoglucanase H or CelH) from Clostridium (Ruminiclostridium) thermocellum to the C-terminus of Dtur CelA, an interesting hyperthermostable endoglucanase from Dictyoglomus turgidum. The activity and binding rate of both native and chimeric enzyme were evaluated on soluble and insoluble polysaccharides. The addition of a CBM resulted in a cellulase with enhanced stability at extreme pHs, higher affinity and activity on insoluble cellulose.
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32
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Hoßbach J, Bußwinkel F, Kranz A, Wattjes J, Cord-Landwehr S, Moerschbacher BM. A chitin deacetylase of Podospora anserina has two functional chitin binding domains and a unique mode of action. Carbohydr Polym 2018; 183:1-10. [DOI: 10.1016/j.carbpol.2017.11.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 11/02/2017] [Accepted: 11/02/2017] [Indexed: 02/06/2023]
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33
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Orłowski A, Artzi L, Cazade PA, Gunnoo M, Bayer EA, Thompson D. On the distinct binding modes of expansin and carbohydrate-binding module proteins on crystalline and nanofibrous cellulose: implications for cellulose degradation by designer cellulosomes. Phys Chem Chem Phys 2018. [DOI: 10.1039/c7cp07764e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Transformation of cellulose into monosaccharides can be achieved by hydrolysis of the cellulose chains, carried out by a special group of enzymes known as cellulases.
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Affiliation(s)
- Adam Orłowski
- Department of Physics
- Bernal Institute
- University of Limerick
- Ireland
| | - Lior Artzi
- Department of Biomolecular Sciences
- The Weizmann Institute of Science
- Rehovot
- Israel
| | | | | | - Edward A. Bayer
- Department of Biomolecular Sciences
- The Weizmann Institute of Science
- Rehovot
- Israel
| | - Damien Thompson
- Department of Physics
- Bernal Institute
- University of Limerick
- Ireland
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34
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Hettle A, Fillo A, Abe K, Massel P, Pluvinage B, Langelaan DN, Smith SP, Boraston AB. Properties of a family 56 carbohydrate-binding module and its role in the recognition and hydrolysis of β-1,3-glucan. J Biol Chem 2017; 292:16955-16968. [PMID: 28827308 DOI: 10.1074/jbc.m117.806711] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 08/11/2017] [Indexed: 11/06/2022] Open
Abstract
BH0236 from Bacillus halodurans is a multimodular β-1,3-glucanase comprising an N-terminal family 81 glycoside hydrolase catalytic module, an internal family 6 carbohydrate-binding module (CBM) that binds the nonreducing end of β-1,3-glucan chains, and an uncharacterized C-terminal module classified into CBM family 56. Here, we determined that this latter CBM, BhCBM56, bound the soluble β-1,3-glucan laminarin with a dissociation constant (Kd ) of ∼26 μm and displayed higher affinity for insoluble β-1,3-glucans with Kd values of ∼2-10 μm but lacked affinity for β-1,3-glucooligosaccharides. The X-ray crystal structure of BhCBM56 and NMR-derived chemical shift mapping of the binding site revealed a β-sandwich fold, with the face of one β-sheet possessing the β-1,3-glucan-binding surface. On the basis of the functional and structural properties of BhCBM56, we propose that it binds a quaternary polysaccharide structure, most likely the triple helix adopted by polymerized β-1,3-glucans. Consistent with the BhCBM56 and BhCBM6/56 binding profiles, deletion of the CBM56 from BH0236 decreased activity of the enzyme on the insoluble β-1,3-glucan curdlan but not on soluble laminarin; additional deletion of the CBM6 also did not affect laminarin degradation but further decreased curdlan hydrolysis. The pseudo-atomic solution structure of BH0236 determined by small-angle X-ray scattering revealed structural insights into the nature of avid binding by the BhCBM6/56 pair and how the orientation of the active site in the catalytic module factors into recognition and degradation of β-1,3-glucans. Our findings reinforce the notion that catalytic modules and their cognate CBMs have complementary specificities, including targeting of polysaccharide quaternary structure.
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Affiliation(s)
- Andrew Hettle
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada and
| | - Alexander Fillo
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada and
| | - Kento Abe
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada and
| | - Patricia Massel
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada and
| | - Benjamin Pluvinage
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada and
| | - David N Langelaan
- the Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Steven P Smith
- the Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Alisdair B Boraston
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada and
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35
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Duan CJ, Huang MY, Pang H, Zhao J, Wu CX, Feng JX. Characterization of a novel theme C glycoside hydrolase family 9 cellulase and its CBM-chimeric enzymes. Appl Microbiol Biotechnol 2017; 101:5723-5737. [DOI: 10.1007/s00253-017-8320-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/09/2017] [Accepted: 04/29/2017] [Indexed: 01/27/2023]
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36
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Functional analysis of arabinofuranosidases and a xylanase of Corynebacterium alkanolyticum for arabinoxylan utilization in Corynebacterium glutamicum. Appl Microbiol Biotechnol 2017; 101:5019-5032. [DOI: 10.1007/s00253-017-8280-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 03/22/2017] [Accepted: 03/29/2017] [Indexed: 11/27/2022]
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37
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Pires VMR, Pereira PMM, Brás JLA, Correia M, Cardoso V, Bule P, Alves VD, Najmudin S, Venditto I, Ferreira LMA, Romão MJ, Carvalho AL, Fontes CMGA, Prazeres DM. Stability and Ligand Promiscuity of Type A Carbohydrate-binding Modules Are Illustrated by the Structure of Spirochaeta thermophila StCBM64C. J Biol Chem 2017; 292:4847-4860. [PMID: 28179427 DOI: 10.1074/jbc.m116.767541] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/07/2017] [Indexed: 11/06/2022] Open
Abstract
Deconstruction of cellulose, the most abundant plant cell wall polysaccharide, requires the cooperative activity of a large repertoire of microbial enzymes. Modular cellulases contain non-catalytic type A carbohydrate-binding modules (CBMs) that specifically bind to the crystalline regions of cellulose, thus promoting enzyme efficacy through proximity and targeting effects. Although type A CBMs play a critical role in cellulose recycling, their mechanism of action remains poorly understood. Here we produced a library of recombinant CBMs representative of the known diversity of type A modules. The binding properties of 40 CBMs, in fusion with an N-terminal GFP domain, revealed that type A CBMs possess the ability to recognize different crystalline forms of cellulose and chitin over a wide range of temperatures, pH levels, and ionic strengths. A Spirochaeta thermophila CBM64, in particular, displayed plasticity in its capacity to bind both crystalline and soluble carbohydrates under a wide range of extreme conditions. The structure of S. thermophila StCBM64C revealed an untwisted, flat, carbohydrate-binding interface comprising the side chains of four tryptophan residues in a co-planar linear arrangement. Significantly, two highly conserved asparagine side chains, each one located between two tryptophan residues, are critical to insoluble and soluble glucan recognition but not to bind xyloglucan. Thus, CBM64 compact structure and its extended and versatile ligand interacting platform illustrate how type A CBMs target their appended plant cell wall-degrading enzymes to a diversity of recalcitrant carbohydrates under a wide range of environmental conditions.
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Affiliation(s)
- Virgínia M R Pires
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal
| | - Pedro M M Pereira
- the Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Joana L A Brás
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal.,NZYTech Genes Enzymes, 1649-038 Lisboa, Portugal, and
| | - Márcia Correia
- the UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Vânia Cardoso
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal.,NZYTech Genes Enzymes, 1649-038 Lisboa, Portugal, and
| | - Pedro Bule
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal
| | - Victor D Alves
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal
| | - Shabir Najmudin
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal
| | - Immacolata Venditto
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal
| | - Luís M A Ferreira
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal.,NZYTech Genes Enzymes, 1649-038 Lisboa, Portugal, and
| | - Maria João Romão
- the UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Ana Luísa Carvalho
- the UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Carlos M G A Fontes
- From the CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Pólo Universitário da Ajuda, 1300-477 Lisboa, Portugal, .,NZYTech Genes Enzymes, 1649-038 Lisboa, Portugal, and
| | - Duarte Miguel Prazeres
- the Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal,
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38
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Grisolia MJ, Peralta DA, Valdez HA, Barchiesi J, Gomez-Casati DF, Busi MV. The targeting of starch binding domains from starch synthase III to the cell wall alters cell wall composition and properties. PLANT MOLECULAR BIOLOGY 2017; 93:121-135. [PMID: 27770231 DOI: 10.1007/s11103-016-0551-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 10/13/2016] [Indexed: 05/11/2023]
Abstract
Starch binding domains of starch synthase III from Arabidopsis thaliana (SBD123) binds preferentially to cell wall polysaccharides rather than to starch in vitro. Transgenic plants overexpressing SBD123 in the cell wall are larger than wild type. Cell wall components are altered in transgenic plants. Transgenic plants are more susceptible to digestion than wild type and present higher released glucose content. Our results suggest that the transgenic plants have an advantage for the production of bioethanol in terms of saccharification of essential substrates. The plant cell wall, which represents a major source of biomass for biofuel production, is composed of cellulose, hemicelluloses, pectins and lignin. A potential biotechnological target for improving the production of biofuels is the modification of plant cell walls. This modification is achieved via several strategies, including, among others, altering biosynthetic pathways and modifying the associations and structures of various cell wall components. In this study, we modified the cell wall of A. thaliana by targeting the starch-binding domains of A. thaliana starch synthase III to this structure. The resulting transgenic plants (E8-SDB123) showed an increased biomass, higher levels of both fermentable sugars and hydrolyzed cellulose and altered cell wall properties such as higher laxity and degradability, which are valuable characteristics for the second-generation biofuels industry. The increased biomass and degradability phenotype of E8-SBD123 plants could be explained by the putative cell-wall loosening effect of the in tandem starch binding domains. Based on these results, our approach represents a promising biotechnological tool for reducing of biomass recalcitrance and therefore, the need for pretreatments.
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Affiliation(s)
- Mauricio J Grisolia
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas (CEFOBI - CONICET), Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Diego A Peralta
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas (CEFOBI - CONICET), Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Hugo A Valdez
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martin, Chascomús, Buenos Aires, Argentina
- Centro de Investigación y Desarrollo en Fermentaciones Industriales (CINDEFI), 50 y 115, 1900, La Plata, Buenos Aires, Argentina
| | - Julieta Barchiesi
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas (CEFOBI - CONICET), Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Diego F Gomez-Casati
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas (CEFOBI - CONICET), Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martin, Chascomús, Buenos Aires, Argentina
| | - María V Busi
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas (CEFOBI - CONICET), Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina.
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martin, Chascomús, Buenos Aires, Argentina.
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Abstract
For modern biotechnology there is a steady need to identify novel enzymes. In biotechnological applications, however, enzymes often must function under extreme and nonnatural conditions (i.e., in the presence of solvents, high temperature and/or at extreme pH values). Cellulases have many industrial applications from the generation of bioethanol, a realistic long-term energy source, to the finishing of textiles. These industrial processes require cellulolytic activity under a wide range of pH, temperature, and ionic conditions, and they are usually carried out by mixtures of cellulases. Investigation of the broad diversity of cellulolytic enzymes involved in the natural degradation of cellulose is necessary for optimizing these processes.
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Affiliation(s)
- Nele Ilmberger
- Microbiology & Biotechnology, Biocenter Klein Flottbek, University of Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Wolfgang R Streit
- Microbiology & Biotechnology, Biocenter Klein Flottbek, University of Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany.
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40
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Meirovitch S, Shtein Z, Ben-Shalom T, Lapidot S, Tamburu C, Hu X, Kluge JA, Raviv U, Kaplan DL, Shoseyov O. Spider Silk-CBD-Cellulose Nanocrystal Composites: Mechanism of Assembly. Int J Mol Sci 2016; 17:E1573. [PMID: 27649169 PMCID: PMC5037840 DOI: 10.3390/ijms17091573] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/22/2016] [Accepted: 09/08/2016] [Indexed: 11/17/2022] Open
Abstract
The fabrication of cellulose-spider silk bio-nanocomposites comprised of cellulose nanocrystals (CNCs) and recombinant spider silk protein fused to a cellulose binding domain (CBD) is described. Silk-CBD successfully binds cellulose, and unlike recombinant silk alone, silk-CBD self-assembles into microfibrils even in the absence of CNCs. Silk-CBD-CNC composite sponges and films show changes in internal structure and CNC alignment related to the addition of silk-CBD. The silk-CBD sponges exhibit improved thermal and structural characteristics in comparison to control recombinant spider silk sponges. The glass transition temperature (Tg) of the silk-CBD sponge was higher than the control silk sponge and similar to native dragline spider silk fibers. Gel filtration analysis, dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and cryo-transmission electron microscopy (TEM) indicated that silk-CBD, but not the recombinant silk control, formed a nematic liquid crystalline phase similar to that observed in native spider silk during the silk spinning process. Silk-CBD microfibrils spontaneously formed in solution upon ultrasonication. We suggest a model for silk-CBD assembly that implicates CBD in the central role of driving the dimerization of spider silk monomers, a process essential to the molecular assembly of spider-silk nanofibers and silk-CNC composites.
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Affiliation(s)
- Sigal Meirovitch
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
| | - Zvi Shtein
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
| | - Tal Ben-Shalom
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
| | - Shaul Lapidot
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
| | - Carmen Tamburu
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 91904, Israel.
| | - Xiao Hu
- Department of Biomedical Engineering, 4 Colby Street, Tufts University, Medford, MA 02155, USA.
- Department of Physics and Astronomy, Rowan University, Glassboro, NJ 08028, USA.
| | - Jonathan A Kluge
- Department of Biomedical Engineering, 4 Colby Street, Tufts University, Medford, MA 02155, USA.
| | - Uri Raviv
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 91904, Israel.
| | - David L Kaplan
- Department of Biomedical Engineering, 4 Colby Street, Tufts University, Medford, MA 02155, USA.
| | - Oded Shoseyov
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
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41
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Tanimoto S, Higashi M, Yoshida N, Nakano H. The ion dependence of carbohydrate binding of CBM36: an MD and 3D-RISM study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:344005. [PMID: 27366974 DOI: 10.1088/0953-8984/28/34/344005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The molecular recognition process of the carbohydrate-binding module family 36 (CBM36) was examined theoretically. The mechanism of xylan binding by CBM36 and the role of Ca(2+) were investigated by the combined use of molecular dynamics simulations and the 3D reference interaction site model method. The CBM36 showed affinity for xylan after Ca(2+) binding, but not after Mg(2+) binding. Free-energy component analysis of the xylan-binding process revealed that the major factor for xylan-binding affinity is the electrostatic interaction between the Ca(2+) and the hydroxyl oxygens of xylan. The van der Waals interaction between the hydrophobic side chain of CBM36 and the glucopyranose ring of xylan also contributes to the stabilization of the xylan-binding state. Dehydration on the formation of the complex has the opposite effect on these interactions. The affinity of CBM36 for xylan results from a balance of the interactions between the binding ion and solvents, hydrophilic residues around xylan, and the hydroxyl oxygens of xylan. When CBM binds Ca(2+), these interactions are well balanced; in contrast, when CBM binds Mg(2+), the dehydration penalty is excessively large.
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Affiliation(s)
- Shoichi Tanimoto
- Department of Chemistry, Graduate School of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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Das SN, Wagenknecht M, Nareddy PK, Bhuvanachandra B, Niddana R, Balamurugan R, Swamy MJ, Moerschbacher BM, Podile AR. Amino Groups of Chitosan Are Crucial for Binding to a Family 32 Carbohydrate Binding Module of a Chitosanase from Paenibacillus elgii. J Biol Chem 2016; 291:18977-90. [PMID: 27405759 DOI: 10.1074/jbc.m116.721332] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Indexed: 11/06/2022] Open
Abstract
We report here the role and mechanism of specificity of a family 32 carbohydrate binding module (CBM32) of a glycoside hydrolase family 8 chitosanase from Paenibacillus elgii (PeCsn). Both the activity and mode of action of PeCsn toward soluble chitosan polymers were not different with/without the CBM32 domain of P. elgii (PeCBM32). The decreased activity of PeCsn without PeCBM32 on chitosan powder suggested that PeCBM32 increases the relative concentration of enzyme on the substrate and thereby enhanced enzymatic activity. PeCBM32 specifically bound to polymeric and oligomeric chitosan and showed very weak binding to chitin and cellulose. In isothermal titration calorimetry, the binding stoichiometry of 2 and 1 for glucosamine monosaccharide (GlcN) and disaccharide (GlcN)2, respectively, was indicative of two binding sites in PeCBM32. A three-dimensional model-guided site-directed mutagenesis and the use of defined disaccharides varying in the pattern of acetylation suggested that the amino groups of chitosan and the polar residues Glu-16 and Glu-38 of PeCBM32 play a crucial role for the observed binding. The specificity of CBM32 has been further elucidated by a generated fusion protein PeCBM32-eGFP that binds to the chitosan exposing endophytic infection structures of Puccinia graminis f. sp. tritici Phylogenetic analysis showed that CBM32s appended to chitosanases are highly conserved across different chitosanase families suggesting their role in chitosan recognition and degradation. We have identified and characterized a chitosan-specific CBM32 useful for in situ staining of chitosans in the fungal cell wall during plant-fungus interaction.
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Affiliation(s)
| | - Martin Wagenknecht
- the Institute of Plant Biology and Biotechnology, Westphalian Wilhelms-University of Münster, 48143 Münster, Germany
| | | | | | - Ramana Niddana
- School of Chemistry, University of Hyderabad, 500046-Hyderabad, India and
| | | | - Musti J Swamy
- School of Chemistry, University of Hyderabad, 500046-Hyderabad, India and
| | - Bruno M Moerschbacher
- the Institute of Plant Biology and Biotechnology, Westphalian Wilhelms-University of Münster, 48143 Münster, Germany
| | - Appa Rao Podile
- From the Department of Plant Sciences, School of Life Sciences,
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43
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Tuveng TR, Arntzen MØ, Bengtsson O, Gardner JG, Vaaje-Kolstad G, Eijsink VG. Proteomic investigation of the secretome ofCellvibrio japonicusduring growth on chitin. Proteomics 2016; 16:1904-14. [DOI: 10.1002/pmic.201500419] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 04/05/2016] [Accepted: 05/09/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Tina Rise Tuveng
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences (NMBU); Aas Norway
| | - Magnus Øverlie Arntzen
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences (NMBU); Aas Norway
| | - Oskar Bengtsson
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences (NMBU); Aas Norway
| | - Jeffrey G. Gardner
- Department of Biological Sciences; University of Maryland - Baltimore County; Baltimore MD USA
| | - Gustav Vaaje-Kolstad
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences (NMBU); Aas Norway
| | - Vincent G.H. Eijsink
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences (NMBU); Aas Norway
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44
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Fadel F, Zhao Y, Cousido-Siah A, Ruiz FX, Mitschler A, Podjarny A. X-Ray Crystal Structure of the Full Length Human Chitotriosidase (CHIT1) Reveals Features of Its Chitin Binding Domain. PLoS One 2016; 11:e0154190. [PMID: 27111557 PMCID: PMC4844120 DOI: 10.1371/journal.pone.0154190] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 04/11/2016] [Indexed: 12/15/2022] Open
Abstract
Chitinases are enzymes that catalyze the hydrolysis of chitin. Human chitotriosidase (CHIT1) is one of the two active human chitinases, involved in the innate immune response and highly expressed in a variety of diseases. CHIT1 is composed of a catalytic domain linked by a hinge to its chitin binding domain (ChBD). This latter domain belongs to the carbohydrate-binding module family 14 (CBM14 family) and facilitates binding to chitin. So far, the available crystal structures of the human chitinase CHIT1 and the Acidic Mammalian Chitinase (AMCase) comprise only their catalytic domain. Here, we report a crystallization strategy combining cross-seeding and micro-seeding cycles which allowed us to obtain the first crystal structure of the full length CHIT1 (CHIT1-FL) at 1.95 Å resolution. The CHIT1 chitin binding domain (ChBDCHIT1) structure shows a distorted β-sandwich 3D fold, typical of CBM14 family members. Accordingly, ChBDCHIT1 presents six conserved cysteine residues forming three disulfide bridges and several exposed aromatic residues that probably are involved in chitin binding, including the highly conserved Trp465 in a surface- exposed conformation. Furthermore, ChBDCHIT1 presents a positively charged surface which may be involved in electrostatic interactions. Our data highlight the strong structural conservation of CBM14 family members and uncover the structural similarity between the human ChBDCHIT1, tachycitin and house mite dust allergens. Overall, our new CHIT1-FL structure, determined with an adapted crystallization approach, is one of the few complete bi-modular chitinase structures available and reveals the structural features of a human CBM14 domain.
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Affiliation(s)
- Firas Fadel
- Department of Integrative Biology, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104, INSERM U 964, Université de Strasbourg, Illkirch, France
- * E-mail: (FF); (AP)
| | - Yuguang Zhao
- Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford, United Kingdom
| | - Alexandra Cousido-Siah
- Department of Integrative Biology, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104, INSERM U 964, Université de Strasbourg, Illkirch, France
| | - Francesc X. Ruiz
- Department of Integrative Biology, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104, INSERM U 964, Université de Strasbourg, Illkirch, France
| | - André Mitschler
- Department of Integrative Biology, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104, INSERM U 964, Université de Strasbourg, Illkirch, France
| | - Alberto Podjarny
- Department of Integrative Biology, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104, INSERM U 964, Université de Strasbourg, Illkirch, France
- * E-mail: (FF); (AP)
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45
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Rosales-Mendoza S, Salazar-González JA, Decker EL, Reski R. Implications of plant glycans in the development of innovative vaccines. Expert Rev Vaccines 2016; 15:915-25. [DOI: 10.1586/14760584.2016.1155987] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Sergio Rosales-Mendoza
- Laboratorio de Biofarmacéuticos Recombinantes, Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, Av. Dr. Manuel Nava 6, SLP, Mexico
| | - Jorge A. Salazar-González
- Laboratorio de Biofarmacéuticos Recombinantes, Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, Av. Dr. Manuel Nava 6, SLP, Mexico
| | - Eva L. Decker
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Schaenzlestr. 1, Freiburg, Germany
| | - Ralf Reski
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Schaenzlestr. 1, Freiburg, Germany
- BIOSS – Centre for Biological Signalling Studies, Freiburg, Germany
- FRIAS – Freiburg Institute for Advanced Studies, Freiburg, Germany
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46
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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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47
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Goldstone DC, Metcalf P, Baker EN. Structure of the ectodomain of the electron transporter Rv2874 fromMycobacterium tuberculosisreveals a thioredoxin-like domain combined with a carbohydrate-binding module. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2016; 72:40-8. [DOI: 10.1107/s2059798315021488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 11/12/2015] [Indexed: 11/10/2022]
Abstract
The members of the CcdA family are integral membrane proteins that use a disulfide cascade to transport electrons from the thioredoxin–thioredoxin reductase system in the interior of the cell into the extracytoplasmic space. The core transmembrane portion of this family is often elaborated with additional hydrophilic domains that act as adapters to deliver reducing potential to targets outside the cellular membrane. To investigate the function of family members inMycobacterium tuberculosis, the structure of the C-terminal ectodomain from Rv2874, one of three CcdA-family members present in the genome, was determined. The crystal structure, which was refined at 1.9 Å resolution withR= 0.195 andRfree= 0.219, reveals the predicted thioredoxin-like domain with its conserved Cys-X-X-Cys active-site motif. Unexpectedly, this domain is combined with a second domain with a carbohydrate-binding module (CBM) fold, this being the first reported example of a CBM in association with a thioredoxin-like domain fold. A cavity in the CBM adjacent to the thioredoxin active site suggests a likely carbohydrate-binding site, representing a broadening of the substrate range for CcdA-family members and an expansion of the thioredoxin-domain functionality to carbohydrate modification.
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48
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Kumar A, Zhang S, Wu G, Wu CC, Chen J, Baskaran R, Liu Z. Cellulose binding domain assisted immobilization of lipase (GSlip–CBD) onto cellulosic nanogel: characterization and application in organic medium. Colloids Surf B Biointerfaces 2015; 136:1042-50. [DOI: 10.1016/j.colsurfb.2015.11.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 10/31/2015] [Accepted: 11/02/2015] [Indexed: 01/18/2023]
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49
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Perz V, Zumstein MT, Sander M, Zitzenbacher S, Ribitsch D, Guebitz GM. Biomimetic Approach to Enhance Enzymatic Hydrolysis of the Synthetic Polyester Poly(1,4-butylene adipate): Fusing Binding Modules to Esterases. Biomacromolecules 2015; 16:3889-96. [DOI: 10.1021/acs.biomac.5b01219] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Veronika Perz
- Austrian Centre of Industrial Biotechnology, ACIB, Konrad Lorenz Strasse 20, 3430 Tulln, Austria
| | - Michael Thomas Zumstein
- Department
of Environmental Systems Science, Institute of Biogeochemistry and
Pollutant Dynamics, Swiss Federal Institute of Technology Zurich (ETHZ), Universitätstrasse 16, 8092 Zurich, Switzerland
| | - Michael Sander
- Department
of Environmental Systems Science, Institute of Biogeochemistry and
Pollutant Dynamics, Swiss Federal Institute of Technology Zurich (ETHZ), Universitätstrasse 16, 8092 Zurich, Switzerland
| | - Sabine Zitzenbacher
- Austrian Centre of Industrial Biotechnology, ACIB, Petersgasse 14/V, 8010 Graz, Austria
| | - Doris Ribitsch
- Austrian Centre of Industrial Biotechnology, ACIB, Konrad Lorenz Strasse 20, 3430 Tulln, Austria
- Institute
of Environmental Biotechnology, University of Natural Resources and Life Sciences, Vienna, Konrad Lorenz Strasse 20, 3430 Tulln, Austria
| | - Georg M. Guebitz
- Austrian Centre of Industrial Biotechnology, ACIB, Konrad Lorenz Strasse 20, 3430 Tulln, Austria
- Institute
of Environmental Biotechnology, University of Natural Resources and Life Sciences, Vienna, Konrad Lorenz Strasse 20, 3430 Tulln, Austria
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50
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Pattathil S, Avci U, Zhang T, Cardenas CL, Hahn MG. Immunological Approaches to Biomass Characterization and Utilization. Front Bioeng Biotechnol 2015; 3:173. [PMID: 26579515 PMCID: PMC4623462 DOI: 10.3389/fbioe.2015.00173] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 10/12/2015] [Indexed: 11/13/2022] Open
Abstract
Plant biomass is the major renewable feedstock resource for sustainable generation of alternative transportation fuels to replace fossil carbon-derived fuels. Lignocellulosic cell walls are the principal component of plant biomass. Hence, a detailed understanding of plant cell wall structure and biosynthesis is an important aspect of bioenergy research. Cell walls are dynamic in their composition and structure, varying considerably among different organs, cells, and developmental stages of plants. Hence, tools are needed that are highly efficient and broadly applicable at various levels of plant biomass-based bioenergy research. The use of plant cell wall glycan-directed probes has seen increasing use over the past decade as an excellent approach for the detailed characterization of cell walls. Large collections of such probes directed against most major cell wall glycans are currently available worldwide. The largest and most diverse set of such probes consists of cell wall glycan-directed monoclonal antibodies (McAbs). These McAbs can be used as immunological probes to comprehensively monitor the overall presence, extractability, and distribution patterns among cell types of most major cell wall glycan epitopes using two mutually complementary immunological approaches, glycome profiling (an in vitro platform) and immunolocalization (an in situ platform). Significant progress has been made recently in the overall understanding of plant biomass structure, composition, and modifications with the application of these immunological approaches. This review focuses on such advances made in plant biomass analyses across diverse areas of bioenergy research.
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Affiliation(s)
- Sivakumar Pattathil
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
- Oak Ridge National Laboratory, BioEnergy Science Center (BESC), Oak Ridge, TN, USA
| | - Utku Avci
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
- Oak Ridge National Laboratory, BioEnergy Science Center (BESC), Oak Ridge, TN, USA
| | - Tiantian Zhang
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Claudia L. Cardenas
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Michael G. Hahn
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
- Oak Ridge National Laboratory, BioEnergy Science Center (BESC), Oak Ridge, TN, USA
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