1
|
Talbot SC, Vining KJ, Snelling JW, Clevenger J, Mehlenbacher SA. A haplotype-resolved chromosome-level assembly and annotation of European hazelnut (C. avellana cv. Jefferson) provides insight into mechanisms of eastern filbert blight resistance. G3 (BETHESDA, MD.) 2024; 14:jkae021. [PMID: 38325326 DOI: 10.1093/g3journal/jkae021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 12/11/2023] [Accepted: 01/05/2024] [Indexed: 02/09/2024]
Abstract
European hazelnut (Corylus avellana L.) is an important tree nut crop. Hazelnut production in North America is currently limited in scalability due to Anisogramma anomala, a fungal pathogen that causes Eastern Filbert Blight (EFB) disease in hazelnut. Successful deployment of EFB resistant cultivars has been limited to the state of Oregon, where the breeding program at Oregon State University (OSU) has released cultivars with a dominant allele at a single resistance locus identified by classical breeding, linkage mapping, and molecular markers. C. avellana cultivar "Jefferson" is resistant to the predominant EFB biotype in Oregon and has been selected by the OSU breeding program as a model for hazelnut genetic and genomic research. Here, we present a near complete, haplotype-resolved chromosome-level hazelnut genome assembly for "Jefferson". This new assembly is a significant improvement over a previously published genome draft. Analysis of genomic regions linked to EFB resistance and self-incompatibility confirmed haplotype splitting and identified new gene candidates that are essential for downstream molecular marker development, thereby facilitating breeding efforts.
Collapse
Affiliation(s)
- Samuel C Talbot
- Department of Horticulture, Oregon State University, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331, USA
| | - Kelly J Vining
- Department of Horticulture, Oregon State University, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331, USA
| | - Jacob W Snelling
- Department of Horticulture, Oregon State University, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331, USA
| | - Josh Clevenger
- Hudson Alpha Institute for Biotechnology, 601 Genome Way Northwest, Huntsville, AL 35806, USA
| | - Shawn A Mehlenbacher
- Department of Horticulture, Oregon State University, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331, USA
| |
Collapse
|
2
|
Mu Y, Meng F, Ju X, Li L. Inactivation and process intensification of β-glucosidase in biomass utilization. Appl Microbiol Biotechnol 2023; 107:3191-3204. [PMID: 37058231 DOI: 10.1007/s00253-023-12483-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/07/2023] [Accepted: 03/12/2023] [Indexed: 04/15/2023]
Abstract
Lignocellulosic biomass has emerged as a promising environmental resource. Enzyme catalysis, as one of the most environmentally friendly and efficient tools among various treatments, is used for the conversion of biomass into chemicals and fuels. Cellulase is a complex enzyme composed of β-glucosidase (BGL), endo-β-1,4-glucanase (EG), and exo-β-1,4-glucanase (CBH), which synergistically hydrolyzes cellulose into monosaccharides. BGL, which further deconstructs cellobiose and short-chain cellooligosaccharides obtained by EG and CBH catalysis into glucose, is the most sensitive component of the synergistic enzyme system constituted by the three enzymes and is highly susceptible to inactivation by external conditions, becoming the rate-limiting component in biomass conversion. This paper firstly introduces the source and catalytic mechanism of BGL used in the process of biomass resource utilization. The focus is on the review of various factors affecting BGL activity during hydrolysis, including competitive adsorption of lignin, gas-liquid interface inactivation, thermal inactivation, and solvent effect. And the methods to improve BGL inactivation are proposed from two aspects-substrate initiation and enzyme initiation. In particular, the screening, modification, and alteration of the enzyme molecules themselves are discussed with emphasis. This review can provide novel ideas for studies of BGL inactivation mechanism, containment of inactivation, and activity enhancement. KEY POINTS: • Factors affecting β-glucosidase inactivation are described. • Process intensification is presented in terms of substrate and enzyme. • Solvent selection, protein engineering, and immobilization remain topics of interest.
Collapse
Affiliation(s)
- Yinghui Mu
- School of Chemistry and Life Science, Suzhou University of Science and Technology, Suzhou, 215009, People's Republic of China
| | - Fanjin Meng
- School of Chemistry and Life Science, Suzhou University of Science and Technology, Suzhou, 215009, People's Republic of China
| | - Xin Ju
- School of Chemistry and Life Science, Suzhou University of Science and Technology, Suzhou, 215009, People's Republic of China
| | - Liangzhi Li
- School of Chemistry and Life Science, Suzhou University of Science and Technology, Suzhou, 215009, People's Republic of China.
| |
Collapse
|
3
|
Gadallah EE, El-Borai AM, El-Aassar SA, Beltagy EA. Purification, characterization, immobilization and applications of an enzybiotic β-1,3-1,4-glucanase produced from halotolerant marine Halomonas meridiana ES021. World J Microbiol Biotechnol 2023; 39:89. [PMID: 36740637 PMCID: PMC9899757 DOI: 10.1007/s11274-023-03527-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 01/17/2023] [Indexed: 02/07/2023]
Abstract
Extracellular β-1,3-1,4-glucanase-producing strain Halomonas meridiana ES021 was isolated from Gabal El-Zeit off shore, Red Sea, Egypt. The Extracellular enzyme was partially purified by precipitation with 75% acetone followed by anion exchange chromatography on DEAE-cellulose, where a single protein band was determined with molecular mass of approximately 72 kDa. The Km value was 0.62 mg β-1,3-1,4-glucan/mL and Vmax value was 7936 U/mg protein. The maximum activity for the purified enzyme was observed at 40 °C, pH 5.0, and after 10 min of the reaction. β-1,3-1,4-glucanase showed strong antibacterial effect against Bacillus subtilis, Streptococcus agalactiae and Vibrio damsela. It also showed antifungal effect against Penicillium sp. followed by Aspergillus niger. No toxicity was observed when tested on Artemia salina. Semi-purified β-1,3-1,4-glucanase was noticed to be effective in clarification of different juices at different pH values and different time intervals. The maximum clarification yields were 51.61% and 66.67% on mango juice at 40 °C and pH 5.3 for 2 and 4 h, respectively. To our knowledge, this is the first report of β-1,3-1,4-glucanase enzyme from halotolerant Halomonas species.
Collapse
Affiliation(s)
- Eman E Gadallah
- Botany and Microbiology Department, Faculty of Science, Alexandria University, Alexandria, Egypt.
| | - Aliaa M El-Borai
- Botany and Microbiology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Samy A El-Aassar
- Botany and Microbiology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Ehab A Beltagy
- National Institute of Oceanography and Fisheries (NIOF), Cairo, Egypt
| |
Collapse
|
4
|
The evolutionary advantage of an aromatic clamp in plant family 3 glycoside exo-hydrolases. Nat Commun 2022; 13:5577. [PMID: 36151080 PMCID: PMC9508125 DOI: 10.1038/s41467-022-33180-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/03/2022] [Indexed: 11/08/2022] Open
Abstract
In the barley β-D-glucan glucohydrolase, a glycoside hydrolase family 3 (GH3) enzyme, the Trp286/Trp434 clamp ensures β-D-glucosides binding, which is fundamental for substrate hydrolysis during plant growth and development. We employ mutagenesis, high-resolution X-ray crystallography, and multi-scale molecular modelling methods to examine the binding and conformational behaviour of isomeric β-D-glucosides during substrate-product assisted processive catalysis that operates in GH3 hydrolases. Enzyme kinetics reveals that the W434H mutant retains broad specificity, while W434A behaves as a strict (1,3)-β-D-glucosidase. Investigations of reactant movements on the nanoscale reveal that processivity is sensitive to mutation-specific alterations of the tryptophan clamp. While wild-type and W434H utilise a lateral cavity for glucose displacement and sliding of (1,3)-linked hydrolytic products through the catalytic site without dissociation, consistent with their high hydrolytic rates, W434A does not adopt processive catalysis. Phylogenomic analyses of GH3 hydrolases disclose the evolutionary advantage of the tryptophan clamp that confers broad specificity, high catalytic efficiency, and processivity.
Collapse
|
5
|
Ma J, Li Y, Han S, Jiang Z, Yan Q, Yang S. Structural and biochemical insights into the substrate-binding mechanism of a glycoside hydrolase family 12 β-1,3-1,4-glucanase from Chaetomium sp. J Struct Biol 2021; 213:107774. [PMID: 34329700 DOI: 10.1016/j.jsb.2021.107774] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/16/2021] [Accepted: 07/22/2021] [Indexed: 10/20/2022]
Abstract
β-1,3-1,4-Glucanases are a type of hydrolytic enzymes capable of catalyzing the strict cleavage of β-1,4 glycosidic bonds adjacent to β-1,3 linkages in β-D-glucans and have exhibited great potential in food and feed industrials. In this study, a novel glycoside hydrolase (GH) family 12 β-1,3-1,4-glucanase (CtGlu12A) from the thermophilic fungus Chaetomium sp. CQ31 was identified and biochemically characterized. CtGlu12A was most active at pH 7.5 and 65 °C, respectively, and exhibited a high specific activity of 999.9 U mg-1 towards lichenin. It maintained more than 80% of its initial activity in a wide pH range of 5.0-11.0, and up to 60 °C after incubation at 55 °C for 60 min. Moreover, the crystal structures of CtGlu12A with gentiobiose and tetrasccharide were resolved. CtGlu12A had a β-jellyroll fold, and performed retaining mechanism with two glutamic acids severing as the catalytic residues. In the complex structure, cellobiose molecule showed two binding modes, occupying subsites -2 to -1 and subsites + 1 to + 2, respectively. The concave cleft made mixed β-1,3-1,4-glucan substrates maintain a bent conformation to fit into the active site. Overall, this study is not only helpful for the understanding of the substrate-binding model and catalytic mechanism of GH 12 β-1,3-1,4-glucanases, but also provides a basis for further enzymatic engineering of β-1,3-1,4-glucanases.
Collapse
Affiliation(s)
- Junwen Ma
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Engineering, China Agricultural University, Beijing 100083, China
| | - Yanxiao Li
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Engineering, China Agricultural University, Beijing 100083, China
| | - Susu Han
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Zhengqiang Jiang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Qiaojuan Yan
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Engineering, China Agricultural University, Beijing 100083, China
| | - Shaoqing Yang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
| |
Collapse
|
6
|
Deepa P, Thirumeignanam D. Rising trend on the halogen and non-halogen derivatives (Br, Cl, CF 3, F, CH 3 and NH 2) in ruminal β-d-Xylopyranose - a quantum chemical perspective. J Biomol Struct Dyn 2020; 40:449-467. [PMID: 32880211 DOI: 10.1080/07391102.2020.1815577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The utmost aim of the current study is to find significance of the binding affinity in the halogen and non-halogen derivatives: Br, Cl, CF3, F, CH3 and NH2 of β-d-Xylopyranose with the hinge region amino acids of ruminant-β-glycosidase. The interaction energy analysis was carried out in detail through various density functional studies as M062X/def2-QZVP, M062X/LANL2DZ, B3LYP/LANL2DZ and M06HF/LANL2DZ level of theories. The total interaction energy of halogen derivatives: Br, Cl, F and CF3 are -618.21, -599.00, -720.45 and -553.08 kcal/mol respectively, and non-halogen derivative: amine group (NH2) is -87.96 kcal/mol at M062X/def2-QZVP level of theory, which exist with strong binding affinity. Ligand properties: dipole moment, polarizability, volume, molecular mass, electrostatic potential map was evaluated to understand its electrostatic and structural behavior. The nature of the bonds was inferred from the electrostatic potential map for all the halogen and non-halogen derivatives ligand. The stabilization energy from NBO analysis reveals the stability of single hydrogen and halogen bonds (N-H…Br, C-Br…O, N-H…Cl, C-Cl…O, O-H…F, C-H…F, N-H…F, C-F…O, N-H…O, O-H…O, N-H…N, O-H…N) in β-d-Xylopyranose and its derivatives. Overall, this study paves way for scientist and medicinal chemist in modelling new drugs. Further, it suggests mutations that increase the binding and may enhance the catalytic action and strengthen the complex diet in animals and hence recommended for experimental synthesis.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Palanisamy Deepa
- Department of Physics, Manonmaniam Sundaranar University, Tirunelveli, India
| | - Duraisamy Thirumeignanam
- Department of Animal Nutrition, Veterinary College and Research Institute, TamilNadu Veterinary and Animal Sciences University, Tirunelveli, India
| |
Collapse
|
7
|
Characterization and diversity of the complete set of GH family 3 enzymes from Rhodothermus marinus DSM 4253. Sci Rep 2020; 10:1329. [PMID: 31992772 PMCID: PMC6987092 DOI: 10.1038/s41598-020-58015-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 01/07/2020] [Indexed: 11/08/2022] Open
Abstract
The genome of Rhodothermus marinus DSM 4253 encodes six glycoside hydrolases (GH) classified under GH family 3 (GH3): RmBgl3A, RmBgl3B, RmBgl3C, RmXyl3A, RmXyl3B and RmNag3. The biochemical function, modelled 3D-structure, gene cluster and evolutionary relationships of each of these enzymes were studied. The six enzymes were clustered into three major evolutionary lineages of GH3: β-N-acetyl-glucosaminidases, β-1,4-glucosidases/β-xylosidases and macrolide β-glucosidases. The RmNag3 with additional β-lactamase domain clustered with the deepest rooted GH3-lineage of β-N-acetyl-glucosaminidases and was active on acetyl-chitooligosaccharides. RmBgl3B displayed β-1,4-glucosidase activity and was the only representative of the lineage clustered with macrolide β-glucosidases from Actinomycetes. The β-xylosidases, RmXyl3A and RmXyl3B, and the β-glucosidases RmBgl3A and RmBgl3C clustered within the major β-glucosidases/β-xylosidases evolutionary lineage. RmXyl3A and RmXyl3B showed β-xylosidase activity with different specificities for para-nitrophenyl (pNP)-linked substrates and xylooligosaccharides. RmBgl3A displayed β-1,4-glucosidase/β-xylosidase activity while RmBgl3C was active on pNP-β-Glc and β-1,3-1,4-linked glucosyl disaccharides. Putative polysaccharide utilization gene clusters were also investigated for both R. marinus DSM 4253 and DSM 4252T (homolog strain). The analysis showed that in the homolog strain DSM 4252TRmar_1080 (RmXyl3A) and Rmar_1081 (RmXyl3B) are parts of a putative polysaccharide utilization locus (PUL) for xylan utilization.
Collapse
|
8
|
Crystal Structure of a GH3 β-Glucosidase from the Thermophilic Fungus Chaetomium thermophilum. Int J Mol Sci 2019; 20:ijms20235962. [PMID: 31783503 PMCID: PMC6929035 DOI: 10.3390/ijms20235962] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/20/2019] [Accepted: 11/25/2019] [Indexed: 11/17/2022] Open
Abstract
Beta-glucosidases (β-glucosidases) have attracted considerable attention in recent years for use in various biotechnological applications. They are also essential enzymes for lignocellulose degradation in biofuel production. However, cost-effective biomass conversion requires the use of highly efficient enzymes. Thus, the search for new enzymes as better alternatives of the currently available enzyme preparations is highly important. Thermophilic fungi are nowadays considered as a promising source of enzymes with improved stability. Here, the crystal structure of a family GH3 β-glucosidase from the thermophilic fungus Chaetomium thermophilum (CtBGL) was determined at a resolution of 2.99 Å. The structure showed the three-domain architecture found in other β-glucosidases with variations in loops and linker regions. The active site catalytic residues in CtBGL were identified as Asp287 (nucleophile) and Glu517 (acid/base). Structural comparison of CtBGL with Protein Data Bank (PDB)-deposited structures revealed variations among glycosylated Asn residues. The enzyme displayed moderate glycosylation compared to other GH3 family β-glucosidases with similar structure. A new glycosylation site at position Asn504 was identified in CtBGL. Moreover, comparison with respect to several thermostability parameters suggested that glycosylation and charged residues involved in electrostatic interactions may contribute to the stability of the enzyme at elevated temperatures. The reported CtBGL structure provides additional insights into the family GH3 enzymes and could offer new ideas for further improvements in β-glucosidases for more efficient use in biotechnological applications regarding cellulose degradation.
Collapse
|
9
|
Karkehabadi S, Hansson H, Mikkelsen NE, Kim S, Kaper T, Sandgren M, Gudmundsson M. Structural studies of a glycoside hydrolase family 3 β-glucosidase from the model fungus Neurospora crassa. Acta Crystallogr F Struct Biol Commun 2018; 74:787-796. [PMID: 30511673 PMCID: PMC6277957 DOI: 10.1107/s2053230x18015662] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 11/05/2018] [Indexed: 11/29/2022] Open
Abstract
The glycoside hydrolase family 3 (GH3) β-glucosidases are a structurally diverse family of enzymes. Cel3A from Neurospora crassa (NcCel3A) belongs to a subfamily of key enzymes that are crucial for industrial biomass degradation. β-Glucosidases hydrolyse the β-1,4 bond at the nonreducing end of cellodextrins. The hydrolysis of cellobiose is of special importance as its accumulation inhibits other cellulases acting on crystalline cellulose. Here, the crystal structure of the biologically relevant dimeric form of NcCel3A is reported. The structure has been refined to 2.25 Å resolution, with an Rcryst and Rfree of 0.18 and 0.22, respectively. NcCel3A is an extensively N-glycosylated glycoprotein that shares 46% sequence identity with Hypocrea jecorina Cel3A, the structure of which has recently been published, and 61% sequence identity with the thermophilic β-glucosidase from Rasamsonia emersonii. NcCel3A is a three-domain protein with a number of extended loops that deepen the active-site cleft of the enzyme. These structures characterize this subfamily of GH3 β-glucosidases and account for the high cellobiose specificity of this subfamily.
Collapse
Affiliation(s)
- Saeid Karkehabadi
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Henrik Hansson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Nils Egil Mikkelsen
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Steve Kim
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Thijs Kaper
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Mikael Gudmundsson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| |
Collapse
|
10
|
Medina LMP, Ardila DC, Zambrano MM, Restrepo S, Barrios AFG. In vitro and in silico characterization of metagenomic soil-derived cellulases capable of hydrolyzing oil palm empty fruit bunch. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2017; 15:55-62. [PMID: 28702370 PMCID: PMC5487248 DOI: 10.1016/j.btre.2017.06.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 05/17/2017] [Accepted: 06/06/2017] [Indexed: 11/29/2022]
Abstract
Diversification of raw material for biofuel production is of interest to both academia and industry. One attractive substrate is a renewable lignocellulosic material such as oil palm (Elaeis guineensis Jacq.) empty fruit bunch (OPEFB), which is a byproduct of the palm oil industry. This study aimed to characterize cellulases active against this substrate. Cellulases with activity against OPEFB were identified from a metagenomic library obtained from DNA extracted from a high-Andean forest ecosystem. Our findings show that the highest cellulolytic activities were obtained at pH and temperature ranges of 4-10 and 30 °C-60 °C, respectively. Due to the heterogeneous character of the system, degradation profiles were fitted to a fractal-like kinetic model, evidencing transport mass transfer limitations. The sequence analysis of the metagenomic library inserts revealed three glycosyl hydrolase families. Finally, molecular docking simulations of the cellulases were carried out corroborating possible exoglucanase and β-glucosidase activity.
Collapse
Affiliation(s)
- Laura Marcela Palma Medina
- Grupo de diseño de Productos y Procesos (GDPP), Department of Chemical Engineering, Universidad de los Andes, Carrera 1E N 18A-10, Bogotá, Colombia
| | - Diana Catalina Ardila
- Grupo de diseño de Productos y Procesos (GDPP), Department of Chemical Engineering, Universidad de los Andes, Carrera 1E N 18A-10, Bogotá, Colombia
| | - María Mercedes Zambrano
- Molecular Genetics, Corporación Corpogen, Cra 5 N° 66A-34, Bogotá, Colombia
- Gebix Center for Genomics and Bioinformatics of Extreme Environments, Cra 5 N° 66A-34, Bogotá, Colombia
| | - Silvia Restrepo
- Department of Biological Sciences, Universidad de los Andes, Carrera 1E N 18A-10, Bogotá, Colombia
| | - Andrés Fernando González Barrios
- Grupo de diseño de Productos y Procesos (GDPP), Department of Chemical Engineering, Universidad de los Andes, Carrera 1E N 18A-10, Bogotá, Colombia
| |
Collapse
|
11
|
Ramírez-Escudero M, Del Pozo MV, Marín-Navarro J, González B, Golyshin PN, Polaina J, Ferrer M, Sanz-Aparicio J. Structural and Functional Characterization of a Ruminal β-Glycosidase Defines a Novel Subfamily of Glycoside Hydrolase Family 3 with Permuted Domain Topology. J Biol Chem 2016; 291:24200-24214. [PMID: 27679487 PMCID: PMC5104943 DOI: 10.1074/jbc.m116.747527] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/16/2016] [Indexed: 01/01/2023] Open
Abstract
Metagenomics has opened up a vast pool of genes for putative, yet uncharacterized, enzymes. It widens our knowledge on the enzyme diversity world and discloses new families for which a clear classification is still needed, as is exemplified by glycoside hydrolase family-3 (GH3) proteins. Herein, we describe a GH3 enzyme (GlyA1) from resident microbial communities in strained ruminal fluid. The enzyme is a β-glucosidase/β-xylosidase that also shows β-galactosidase, β-fucosidase, α-arabinofuranosidase, and α-arabinopyranosidase activities. Short cello- and xylo-oligosaccharides, sophorose and gentibiose, are among the preferred substrates, with the large polysaccharide lichenan also being hydrolyzed by GlyA1. The determination of the crystal structure of the enzyme in combination with deletion and site-directed mutagenesis allowed identification of its unusual domain composition and the active site architecture. Complexes of GlyA1 with glucose, galactose, and xylose allowed picturing the catalytic pocket and illustrated the molecular basis of the substrate specificity. A hydrophobic platform defined by residues Trp-711 and Trp-106, located in a highly mobile loop, appears able to allocate differently β-linked bioses. GlyA1 includes an additional C-terminal domain previously unobserved in GH3 members, but crystallization of the full-length enzyme was unsuccessful. Therefore, small angle x-ray experiments have been performed to investigate the molecular flexibility and overall putative shape. This study provided evidence that GlyA1 defines a new subfamily of GH3 proteins with a novel permuted domain topology. Phylogenetic analysis indicates that this topology is associated with microbes inhabiting the digestive tracts of ruminants and other animals, feeding on chemically diverse plant polymeric materials.
Collapse
Affiliation(s)
- Mercedes Ramírez-Escudero
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
| | - Mercedes V Del Pozo
- the Institute of Catalysis and Petrochemistry, Consejo Superior de Investigaciones Científicas, Marie Curie 2, Cantoblanco, 28049 Madrid, Spain
| | - Julia Marín-Navarro
- the Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas, Carrer Catedràtic Agustín Escardino Benlloch 7, 46980 Paterna, Valencia, Spain
| | - Beatriz González
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
| | - Peter N Golyshin
- the School of Biological Sciences, Bangor University, LL57 2UW Gwynedd, United Kingdom, and.,the Immanuel Kant Baltic Federal University, 236040 Kaliningrad, Russia
| | - Julio Polaina
- the Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas, Carrer Catedràtic Agustín Escardino Benlloch 7, 46980 Paterna, Valencia, Spain
| | - Manuel Ferrer
- the Institute of Catalysis and Petrochemistry, Consejo Superior de Investigaciones Científicas, Marie Curie 2, Cantoblanco, 28049 Madrid, Spain,
| | - Julia Sanz-Aparicio
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain,
| |
Collapse
|
12
|
Baba Y, Sumitani JI, Tanaka K, Tani S, Kawaguchi T. Site-saturation mutagenesis for β-glucosidase 1 from Aspergillus aculeatus to accelerate the saccharification of alkaline-pretreated bagasse. Appl Microbiol Biotechnol 2016; 100:10495-10507. [DOI: 10.1007/s00253-016-7726-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 06/30/2016] [Accepted: 07/04/2016] [Indexed: 01/05/2023]
|
13
|
Gudmundsson M, Hansson H, Karkehabadi S, Larsson A, Stals I, Kim S, Sunux S, Fujdala M, Larenas E, Kaper T, Sandgren M. Structural and functional studies of the glycoside hydrolase family 3 β-glucosidase Cel3A from the moderately thermophilic fungus Rasamsonia emersonii. Acta Crystallogr D Struct Biol 2016; 72:860-70. [PMID: 27377383 PMCID: PMC4932919 DOI: 10.1107/s2059798316008482] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 05/25/2016] [Indexed: 12/16/2022] Open
Abstract
The filamentous fungus Hypocrea jecorina produces a number of cellulases and hemicellulases that act in a concerted fashion on biomass and degrade it into monomeric or oligomeric sugars. β-Glucosidases are involved in the last step of the degradation of cellulosic biomass and hydrolyse the β-glycosidic linkage between two adjacent molecules in dimers and oligomers of glucose. In this study, it is shown that substituting the β-glucosidase from H. jecorina (HjCel3A) with the β-glucosidase Cel3A from the thermophilic fungus Rasamsonia emersonii (ReCel3A) in enzyme mixtures results in increased efficiency in the saccharification of lignocellulosic materials. Biochemical characterization of ReCel3A, heterologously produced in H. jecorina, reveals a preference for disaccharide substrates over longer gluco-oligosaccharides. Crystallographic studies of ReCel3A revealed a highly N-glycosylated three-domain dimeric protein, as has been observed previously for glycoside hydrolase family 3 β-glucosidases. The increased thermal stability and saccharification yield and the superior biochemical characteristics of ReCel3A compared with HjCel3A and mixtures containing HjCel3A make ReCel3A an excellent candidate for addition to enzyme mixtures designed to operate at higher temperatures.
Collapse
Affiliation(s)
- Mikael Gudmundsson
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Henrik Hansson
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Saeid Karkehabadi
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Anna Larsson
- Department of Cell and Molecular Biology, Uppsala University, Box 596, 751 24 Uppsala, Sweden
| | - Ingeborg Stals
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Ghent University, Ledeganckstraat 35, B-9000 Ghent, Belgium
| | - Steve Kim
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Sergio Sunux
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Meredith Fujdala
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Edmund Larenas
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Thijs Kaper
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Mats Sandgren
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| |
Collapse
|
14
|
Su H, Sheng X, Liu Y. Insights into the catalytic mechanism of N-acetylglucosaminidase glycoside hydrolase from Bacillus subtilis: a QM/MM study. Org Biomol Chem 2016; 14:3432-42. [DOI: 10.1039/c6ob00320f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
QM/MM calculations on NagZs fromBacillus subtilisfurther confirm NagZs to be glycoside phosphorylases rather than glycoside hydrolases.
Collapse
Affiliation(s)
- Hao Su
- Key Laboratory of Colloid and Interface Chemistry
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
| | - Xiang Sheng
- Key Laboratory of Colloid and Interface Chemistry
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
| | - Yongjun Liu
- Key Laboratory of Colloid and Interface Chemistry
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
| |
Collapse
|
15
|
Qin Z, Xiao Y, Yang X, Mesters JR, Yang S, Jiang Z. A unique GCN5-related glucosamine N-acetyltransferase region exist in the fungal multi-domain glycoside hydrolase family 3 β-N-acetylglucosaminidase. Sci Rep 2015; 5:18292. [PMID: 26669854 PMCID: PMC4680927 DOI: 10.1038/srep18292] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 11/16/2015] [Indexed: 11/17/2022] Open
Abstract
Glycoside hydrolase (GH) family 3 β-N-acetylglucosaminidases widely exist in the filamentous fungi, which may play a key role in chitin metabolism of fungi. A multi-domain GH family 3 β-N-acetylglucosaminidase from Rhizomucor miehei (RmNag), exhibiting a potential N-acetyltransferase region, has been recently reported to show great potential in industrial applications. In this study, the crystal structure of RmNag was determined at 2.80 Å resolution. The three-dimensional structure of RmNag showed four distinctive domains, which belong to two distinguishable functional regions — a GH family 3 β-N-acetylglucosaminidase region (N-terminal) and a N-acetyltransferase region (C-terminal). From structural and functional analysis, the C-terminal region of RmNag was identified as a unique tandem array linking general control non-derepressible 5 (GCN5)-related N-acetyltransferase (GNAT), which displayed glucosamine N-acetyltransferase activity. Structural analysis of this glucosamine N-acetyltransferase region revealed that a unique glucosamine binding pocket is located in the pantetheine arm binding terminal region of the conserved CoA binding pocket, which is different from all known GNAT members. This is the first structural report of a glucosamine N-acetyltransferase, which provides novel structural information about substrate specificity of GNATs. The structural and functional features of this multi-domain β-N-acetylglucosaminidase could be useful in studying the catalytic mechanism of GH family 3 proteins.
Collapse
Affiliation(s)
- Zhen Qin
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Yibei Xiao
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany
| | - Xinbin Yang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Jeroen R Mesters
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany
| | - Shaoqing Yang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Zhengqiang Jiang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| |
Collapse
|
16
|
Gabriško M, Janeček Š. Novel family GH3 β-glucosidases or β-xylosidases of unknown function found in various animal groups, including birds and reptiles. Carbohydr Res 2015; 408:44-50. [PMID: 25841058 DOI: 10.1016/j.carres.2015.02.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 02/04/2015] [Accepted: 02/07/2015] [Indexed: 11/26/2022]
Abstract
Proteins from the glycoside hydrolase family 3 (GH3) are important bacterial, fungal and plant enzymes involved in cell wall remodeling, energy metabolism and pathogen defense but no animal GH3 proteins have been reported so far. In presented work we use the in silico approach to describe putative GH3 proteins of animals. Based on tertiary structure modeling, domain organization and transcriptomics data analysis, presence of catalytic and substrate binding residues and evolutionary relationship inference, we assume that there is a monophyletic group of GH3 enzymes (probably β-xylosidases) found in various animal taxa with possible role in development.
Collapse
Affiliation(s)
- Marek Gabriško
- Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK-84551 Bratislava, Slovakia.
| | - Štefan Janeček
- Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK-84551 Bratislava, Slovakia
| |
Collapse
|
17
|
Colussi F, da Silva VM, Miller I, Cota J, de Oliveira LC, de Oliveira Neto M, Squina FM, Garcia W. Oligomeric state and structural stability of two hyperthermophilic β-glucosidases from Thermotoga petrophila. Amino Acids 2015; 47:937-48. [PMID: 25637167 DOI: 10.1007/s00726-015-1923-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 01/15/2015] [Indexed: 01/10/2023]
Abstract
The β-glucosidases are enzymes essential for several industrial applications, especially in the field of plant structural polysaccharides conversion into bioenergy and bioproducts. In a recent study, we have provided a biochemical characterization of two hyperthermostable β-glucosidases from Thermotoga petrophila belonging to the families GH1 (TpBGL1) and GH3 (TpBGL3). Here, as part of a continuing investigation, the oligomeric state, the net charge, and the structural stability, at acidic pH, of the TpBGL1 and TpBGL3 were characterized and compared. Enzymatic activity is directly related to the balance between protonation and conformational changes. Interestingly, our results indicated that there were no significant changes in the secondary, tertiary and quaternary structures of the β-glucosidases at temperatures below 80 °C. Furthermore, the results indicated that both the enzymes are stable homodimers in solution. Therefore, the observed changes in the enzymatic activities are due to variations in pH that modify protonation of the enzymes residues and the net charge, directly affecting the interactions with ligands. Finally, the results showed that the two β-glucosidases displayed different pH dependence of thermostability at temperatures above 80 °C. TpBGL1 showed higher stability at pH 6 than at pH 4, while TpBGL3 showed similar stability at both pH values. This study provides a useful comparison of the structural stability, at acidic pH, of two different hyperthermostable β-glucosidases and how it correlates with the activity of the enzymes. The information described here can be useful for biotechnological applications in the biofuel and food industries.
Collapse
Affiliation(s)
- Francieli Colussi
- Centro de Ciências Naturais e Humanas (CCNH), Universidade Federal do ABC (UFABC), Santo André, SP, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Nakajima M, Yoshida R, Miyanaga A, Taguchi H. Crystallization and preliminary X-ray diffraction analysis of Lin1840, a putative β-glucosidase from Listeria innocua. ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS 2014; 70:1398-401. [PMID: 25286948 DOI: 10.1107/s2053230x14018597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/14/2014] [Indexed: 11/11/2022]
Abstract
Lin1840 is a putative β-glucosidase that is predicted to be involved in 1,2-β-glucan metabolism since the lin1839 gene encoding a 1,2-β-oligoglucan phosphorylase and the lin1840 gene are located in the same gene cluster. Here, Lin1840 was crystallized. The crystals of Lin1840 diffracted to beyond 1.8 Å resolution. The crystal belonged to space group I121, with unit-cell parameters a = 89.75, b = 95.10, c = 215.00 Å, α = 90.00, β = 96.34, γ = 90.00°.
Collapse
Affiliation(s)
- Masahiro Nakajima
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Ryuta Yoshida
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Akimasa Miyanaga
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Hayao Taguchi
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| |
Collapse
|
19
|
Horton JR, Nugent RL, Li A, Mabuchi MY, Fomenkov A, Cohen-Karni D, Griggs RM, Zhang X, Wilson GG, Zheng Y, Xu SY, Cheng X. Structure and mutagenesis of the DNA modification-dependent restriction endonuclease AspBHI. Sci Rep 2014; 4:4246. [PMID: 24604015 PMCID: PMC3946040 DOI: 10.1038/srep04246] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 02/13/2014] [Indexed: 12/13/2022] Open
Abstract
The modification-dependent restriction endonuclease AspBHI recognizes 5-methylcytosine (5mC) in the double-strand DNA sequence context of (C/T)(C/G)(5mC)N(C/G) (N = any nucleotide) and cleaves the two strands a fixed distance (N12/N16) 3′ to the modified cytosine. We determined the crystal structure of the homo-tetrameric AspBHI. Each subunit of the protein comprises two domains: an N-terminal DNA-recognition domain and a C-terminal DNA cleavage domain. The N-terminal domain is structurally similar to the eukaryotic SET and RING-associated (SRA) domain, which is known to bind to a hemi-methylated CpG dinucleotide. The C-terminal domain is structurally similar to classic Type II restriction enzymes and contains the endonuclease catalytic-site motif of DX20EAK. To understand how specific amino acids affect AspBHI recognition preference, we generated a homology model of the AspBHI-DNA complex, and probed the importance of individual amino acids by mutagenesis. Ser41 and Arg42 are predicted to be located in the DNA minor groove 5′ to the modified cytosine. Substitution of Ser41 with alanine (S41A) and cysteine (S41C) resulted in mutants with altered cleavage activity. All 19 Arg42 variants resulted in loss of endonuclease activity.
Collapse
Affiliation(s)
- John R Horton
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| | - Rebecca L Nugent
- 1] New England Biolabs, 240 County Road, Ipswich, MA 01938, USA [2]
| | - Andrew Li
- New England Biolabs, 240 County Road, Ipswich, MA 01938, USA
| | | | - Alexey Fomenkov
- New England Biolabs, 240 County Road, Ipswich, MA 01938, USA
| | | | - Rose M Griggs
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| | - Xing Zhang
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| | | | - Yu Zheng
- New England Biolabs, 240 County Road, Ipswich, MA 01938, USA
| | - Shuang-yong Xu
- New England Biolabs, 240 County Road, Ipswich, MA 01938, USA
| | - Xiaodong Cheng
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| |
Collapse
|
20
|
Casey LW, Mark AE, Kobe B. Small-Angle X-Ray Scattering for the Discerning Macromolecular Crystallographer. Aust J Chem 2014. [DOI: 10.1071/ch14396] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The role of small-angle X-ray scattering (SAXS) in structural biology is now well established, and its usefulness in combination with macromolecular crystallography is clear. However, the highly averaged SAXS data present a significant risk of over-interpretation to the unwary practitioner, and it can be challenging to frame SAXS results in a manner that maximises the reliability of the conclusions drawn. In this review, a series of recent examples are used to illustrate both the challenges for interpretation and approaches through which these can be overcome.
Collapse
|
21
|
Lima MA, Oliveira-Neto M, Kadowaki MAS, Rosseto FR, Prates ET, Squina FM, Leme AFP, Skaf MS, Polikarpov I. Aspergillus niger β-glucosidase has a cellulase-like tadpole molecular shape: insights into glycoside hydrolase family 3 (GH3) β-glucosidase structure and function. J Biol Chem 2013; 288:32991-3005. [PMID: 24064212 DOI: 10.1074/jbc.m113.479279] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aspergillus niger is known to secrete large amounts of β-glucosidases, which have a variety of biotechnological and industrial applications. Here, we purified an A. niger β-glucosidase (AnBgl1) and conducted its biochemical and biophysical analyses. Purified enzyme with an apparent molecular mass of 116 kDa forms monomers in solution as judged by native gel electrophoresis and has a pI value of 4.55, as found for most of the fungi of β-glucosidases. Surprisingly, the small angle x-ray experiments reveal that AnBgl1 has a tadpole-like structure, with the N-terminal catalytic domain and C-terminal fibronectin III-like domain (FnIII) connected by the long linker peptide (∼100 amino acid residues) in an extended conformation. This molecular organization resembles the one adopted by other cellulases (such as cellobiohydrolases, for example) that frequently contain a catalytic domain linked to the cellulose-binding module that mediates their binding to insoluble and polymeric cellulose. The reasons why AnBgl1, which acts on the small soluble substrates, has a tadpole molecular shape are not entirely clear. However, our enzyme pulldown assays with different polymeric substrates suggest that AnBgl1 has little or no capacity to bind to and to adsorb cellulose, xylan, and starch, but it has high affinity to lignin. Molecular dynamics simulations suggested that clusters of residues located in the C-terminal FnIII domain interact strongly with lignin fragments. The simulations showed that numerous arginine residues scattered throughout the FnIII surface play an important role in the interaction with lignin by means of cation-π stacking with the lignin aromatic rings. These results indicate that the C-terminal FnIII domain could be operational for immobilization of the enzyme on the cell wall and for the prevention of unproductive binding of cellulase to the biomass lignin.
Collapse
Affiliation(s)
- Marisa A Lima
- From the Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos 13560-970, SP
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Fungal Beta-glucosidases: a bottleneck in industrial use of lignocellulosic materials. Biomolecules 2013; 3:612-31. [PMID: 24970184 PMCID: PMC4030957 DOI: 10.3390/biom3030612] [Citation(s) in RCA: 161] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 08/17/2013] [Accepted: 08/20/2013] [Indexed: 12/16/2022] Open
Abstract
Profitable biomass conversion processes are highly dependent on the use of efficient enzymes for lignocellulose degradation. Among the cellulose degrading enzymes, beta-glucosidases are essential for efficient hydrolysis of cellulosic biomass as they relieve the inhibition of the cellobiohydrolases and endoglucanases by reducing cellobiose accumulation. In this review, we discuss the important role beta-glucosidases play in complex biomass hydrolysis and how they create a bottleneck in industrial use of lignocellulosic materials. An efficient beta-glucosidase facilitates hydrolysis at specified process conditions, and key points to consider in this respect are hydrolysis rate, inhibitors, and stability. Product inhibition impairing yields, thermal inactivation of enzymes, and the high cost of enzyme production are the main obstacles to commercial cellulose hydrolysis. Therefore, this sets the stage in the search for better alternatives to the currently available enzyme preparations either by improving known or screening for new beta-glucosidases.
Collapse
|
23
|
Identification of the acid/base catalyst of a glycoside hydrolase family 3 (GH3) beta-glucosidase from Aspergillus niger ASKU28. Biochim Biophys Acta Gen Subj 2013. [PMID: 23201198 DOI: 10.1016/j.bbagen.2012.11.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND The commercially important glycoside hydrolase family 3 (GH3) beta-glucosidases from Aspergillus niger are anomeric-configuration-retaining enzymes that operate through the canonical double-displacement glycosidase mechanism. Whereas the catalytic nucleophile is readily identified across all GH3 members by sequence alignments, the acid/base catalyst in this family is phylogenetically variable and less readily divined. METHODS In this report, we employed three-dimensional structure homology modeling and detailed kinetic analysis of site-directed mutants to identify the catalytic acid/base of a GH3 beta-glucosidase from A. niger ASKU28. RESULTS In comparison to the wild-type enzyme and other mutants, the E490A variant exhibited greatly reduced k(cat) and k(cat)/K(m) values toward the natural substrate cellobiose (67,000- and 61,000-fold, respectively). Correspondingly smaller kinetic effects were observed for artificial chromogenic substrates p-nitrophenyl beta-D-glucoside and 2,4-dinitrophenyl beta-D-glucoside, the aglycone leaving groups of which are less dependent on acid catalysis, although changes in the rate-determining catalytic step were revealed for both. pH-rate profile analyses also implicated E490 as the general acid/base catalyst. Addition of azide as an exogenous nucleophile partially rescued the activity of the E490A variant with the aryl beta-glucosides and yielded beta-glucosyl azide as a product. CONCLUSIONS AND GENERAL SIGNIFICANCE These results strongly support the assignment of E490 as the acid/base catalyst in a beta-glucosidase from A. niger ASKU28, and provide crucial experimental support for the bioinformatic identification of the homologous residue in a range of related GH3 subfamily members.
Collapse
|
24
|
Crystal structures of glycoside hydrolase family 3 β-glucosidase 1 from Aspergillus aculeatus. Biochem J 2013; 452:211-21. [DOI: 10.1042/bj20130054] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
GH3 (glycoside hydrolase family 3) BGLs (β-glucosidases) from filamentous fungi have been widely and commercially used for the supplementation of cellulases. AaBGL1 (Aspergillus aculeatus BGL1) belongs to the GH3 and shows high activity towards cellooligosaccharides up to high degree of polymerization. In the present study we determined the crystal structure of AaBGL1. In addition to the substrate-free structure, the structures of complexes with glucose and various inhibitors were determined. The structure of AaBGL1 is highly glycosylated with 88 monosaccharides (18 N-glycan chains) in the dimer. The largest N-glycan chain comprises ten monosaccharides and is one of the largest glycans ever observed in protein crystal structures. A prominent insertion region exists in a fibronectin type III domain, and this region extends to cover a wide surface area of the enzyme. The subsite +1 of AaBGL1 is highly hydrophobic. Three aromatic residues are present at subsite +1 and are located in short loop regions that are uniquely present in this enzyme. There is a long cleft extending from subsite +1, which appears to be suitable for binding long cellooligosaccharides. The crystal structures of AaBGL1 from the present study provide an important structural basis for the technical improvement of enzymatic cellulosic biomass conversion.
Collapse
|
25
|
Bacik JP, Whitworth GE, Stubbs KA, Vocadlo DJ, Mark BL. Active site plasticity within the glycoside hydrolase NagZ underlies a dynamic mechanism of substrate distortion. ACTA ACUST UNITED AC 2013. [PMID: 23177201 DOI: 10.1016/j.chembiol.2012.09.016] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
NagZ is a glycoside hydrolase that participates in peptidoglycan (PG) recycling by removing β-N-acetylglucosamine from PG fragments that are excised from the bacterial cell wall during growth. Notably, the products formed by NagZ, 1,6-anhydroMurNAc-peptides, activate β-lactam resistance in many Gram-negative bacteria, making this enzyme of interest as a potential therapeutic target. Crystal structure determinations of NagZ from Salmonella typhimurium and Bacillus subtilis in complex with natural substrate, trapped as a glycosyl-enzyme intermediate, and bound to product, define the reaction coordinate of the NagZ family of enzymes. The structures, combined with kinetic studies, reveal an uncommon degree of structural plasticity within the active site of a glycoside hydrolase, and unveil how NagZ drives substrate distortion using a highly mobile loop that contains a conserved histidine that has been proposed as the general acid/base.
Collapse
Affiliation(s)
- John-Paul Bacik
- Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | | | | | | | | |
Collapse
|
26
|
Del Pozo MV, Fernández-Arrojo L, Gil-Martínez J, Montesinos A, Chernikova TN, Nechitaylo TY, Waliszek A, Tortajada M, Rojas A, Huws SA, Golyshina OV, Newbold CJ, Polaina J, Ferrer M, Golyshin PN. Microbial β-glucosidases from cow rumen metagenome enhance the saccharification of lignocellulose in combination with commercial cellulase cocktail. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:73. [PMID: 22998985 PMCID: PMC3477023 DOI: 10.1186/1754-6834-5-73] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 09/14/2012] [Indexed: 05/07/2023]
Abstract
BACKGROUND A complete saccharification of plant polymers is the critical step in the efficient production of bio-alcohols. Beta-glucosidases acting in the degradation of intermediate gluco-oligosaccharides produced by cellulases limit the yield of the final product. RESULTS In the present work, we have identified and then successfully cloned, expressed, purified and characterised 4 highly active beta-glucosidases from fibre-adherent microbial community from the cow rumen. The enzymes were most active at temperatures 45-55°C and pH 4.0-7.0 and exhibited high affinity and activity towards synthetic substrates such as p-nitrophenyl-beta-D-glucopyranoside (pNPbetaG) and pNP-beta-cellobiose, as well as to natural cello-oligosaccharides ranging from cellobiose to cellopentaose. The apparent capability of the most active beta-glucosidase, herein named LAB25g2, was tested for its ability to improve, at low dosage (31.25 units g-1 dry biomass, using pNPbetaG as substrate), the hydrolysis of pre-treated corn stover (dry matter content of 20%; 350 g glucan kg-1 dry biomass) in combination with a beta-glucosidase-deficient commercial Trichoderma reseei cellulase cocktail (5 units g-1 dry biomass in the basis of pNPbetaG). LAB25g2 increased the final hydrolysis yield by a factor of 20% (44.5 ± 1.7% vs. 34.5 ± 1.5% in control conditions) after 96-120 h as compared to control reactions in its absence or in the presence of other commercial beta-glucosidase preparations. The high stability (half-life higher than 5 days at 50°C and pH 5.2) and 2-38000 fold higher (as compared with reported beta-glucosidases) activity towards cello-oligosaccharides may account for its performance in supplementation assays. CONCLUSIONS The results suggest that beta-glucosidases from yet uncultured bacteria from animal digestomes may be of a potential interest for biotechnological processes related to the effective bio-ethanol production in combination with low dosage of commercial cellulases.
Collapse
Affiliation(s)
| | | | | | | | | | - Taras Y Nechitaylo
- Insect Symbiosis Research Group, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany
| | - Agnes Waliszek
- Environmental Microbiology Department, HZI-Helmholtz Centre for Infection Research, D-38124, Braunschweig, Germany
| | | | | | - Sharon A Huws
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, SY23 3DA, UK
| | - Olga V Golyshina
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
| | - Charles J Newbold
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, SY23 3DA, UK
- Centre for Integrated Research in the Rural Environment, Aberystwyth University-Bangor University Partnership (CIRRE), Aberystwyth, SY23 3DA, UK
| | - Julio Polaina
- CSIC, Instituto de Agroquímica y Tecnología de Alimentos, 46980, Paterna, Valencia, Spain
| | | | - Peter N Golyshin
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
- Centre for Integrated Research in the Rural Environment, Aberystwyth University-Bangor University Partnership (CIRRE), Aberystwyth, SY23 3DA, UK
| |
Collapse
|