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Erkanli ME, El-Halabi K, Kang TK, Kim JR. Hotspot Wizard-informed engineering of a hyperthermophilic β-glucosidase for enhanced enzyme activity at low temperatures. Biotechnol Bioeng 2024; 121:2079-2090. [PMID: 38682557 DOI: 10.1002/bit.28732] [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: 02/03/2024] [Revised: 04/11/2024] [Accepted: 04/19/2024] [Indexed: 05/01/2024]
Abstract
Hyperthermophilic enzymes serve as an important source of industrial enzymes due to their high thermostability. Unfortunately, most hyperthermophilic enzymes suffer from reduced activity at low temperatures (e.g., ambient temperature), limiting their applicability. In addition, evolving hyperthermophilic enzymes to increase low temperature activity without compromising other desired properties is generally difficult. In the current study, a variant of β-glucosidase from Pyrococcus furiosus (PfBGL) was engineered to enhance enzyme activity at low temperatures through the construction of a saturation mutagenesis library guided by the HotSpot Wizard analysis, followed by its screening for activity and thermostability. From this library construction and screening, one PfBGL mutant, PfBGL-A4 containing Q214S/A264S/F344I mutations, showed an over twofold increase in β-glucosidase activity at 25 and 50°C compared to the wild type, without compromising high-temperature activity, thermostability and substrate specificity. Our experimental and computational characterizations suggest that the findings with PfBGL-A4 may be due to the elevation of local conformational flexibility around the active site, while slightly compacting the global protein structure. This study showcases the potential of HotSpot Wizard-informed engineering of hyperthermophilic enzymes and underscores the interplays among temperature, enzyme activity, and conformational flexibility in these enzymes.
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Affiliation(s)
- Mehmet Emre Erkanli
- Department of Chemical and Biomolecular Engineering, New York University, Brooklyn, New York, USA
| | - Khalid El-Halabi
- Department of Chemical and Biomolecular Engineering, New York University, Brooklyn, New York, USA
| | - Ted Keunsil Kang
- Department of Chemical and Biomolecular Engineering, New York University, Brooklyn, New York, USA
| | - Jin Ryoun Kim
- Department of Chemical and Biomolecular Engineering, New York University, Brooklyn, New York, USA
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2
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He J, Duan J, Yu P, Li Y, Wang M, Zhang X, Chen Z, Shi P. Characterization of a novel cold-adapted GH1 β-glucosidase from Psychrobacillus glaciei and its application in the hydrolysis of soybean isoflavone glycosides. Curr Res Food Sci 2024; 8:100777. [PMID: 38840809 PMCID: PMC11150966 DOI: 10.1016/j.crfs.2024.100777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 05/16/2024] [Accepted: 05/23/2024] [Indexed: 06/07/2024] Open
Abstract
The novel β-glucosidase gene (pgbgl1) of glycoside hydrolase (GH) family 1 from the psychrotrophic bacterium Psychrobacillus glaciei sp. PB01 was successfully expressed in Escherichia coli BL21 (DE3). The deduced PgBgl1 contained 447 amino acid residues with a calculated molecular mass of 51.4 kDa. PgBgl1 showed its maximum activity at pH 7.0 and 40 °C, and still retained over 10% activity at 0 °C, suggesting that the recombinant PgBgl1 is a cold-adapted enzyme. The substrate specificity, Km, Vmax, and Kcat/Km for the p-Nitrophenyl-β-D-glucopyranoside (pNPG) as the substrate were 1063.89 U/mg, 0.36 mM, 1208.31 U/mg and 3871.92/s, respectively. Furthermore, PgBgl1 demonstrated remarkable stimulation of monosaccharides such as glucose, xylose, and galactose, as well as NaCl. PgBgl1 also demonstrated a high capacity to convert the primary soybean isoflavone glycosides (daidzin, genistin, and glycitin) into their respective aglycones. Overall, PgBgl1 exhibited high catalytic activity towards aryl glycosides, suggesting promising application prospects in the food, animal feed, and pharmaceutical industries.
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Affiliation(s)
- Jinjian He
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China
- College of Horticulture and Landscape, Tianjin Agricultural University, Tianjin, 300392, China
| | - Jiajing Duan
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Pinglian Yu
- Key Laboratory of Yunnan University for Plateau Characteristic Functional Food, School of Chemistry and Chemical Engineering, Zhaotong University, Zhaotong,657000, China
| | - Yuying Li
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China
| | - Mansheng Wang
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China
| | - Xiu Zhang
- Ningxia Key Laboratory for the Development and Application of Microbial Resources in Extreme Environments, College of Biological Science and Engineering, North Minzu University, Yinchuan, 750021, China
| | - Zishu Chen
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China
| | - Pengjun Shi
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China
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3
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Magwaza B, Amobonye A, Pillai S. Microbial β-glucosidases: Recent advances and applications. Biochimie 2024; 225:49-67. [PMID: 38734124 DOI: 10.1016/j.biochi.2024.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/05/2024] [Accepted: 05/06/2024] [Indexed: 05/13/2024]
Abstract
The global β-glucosidase market is currently estimated at ∼400 million USD, and it is expected to double in the next six years; a trend that is mainly ascribed to the demand for the enzyme for biofuel processing. Microbial β-glucosidase, particularly, has thus garnered significant attention due to its ease of production, catalytic efficiency, and versatility, which have all facilitated its biotechnological potential across different industries. Hence, there are continued efforts to screen, produce, purify, characterize and evaluate the industrial applicability of β-glucosidase from actinomycetes, bacteria, fungi, and yeasts. With this rising demand for β-glucosidase, various cost-effective and efficient approaches are being explored to discover, redesign, and enhance their production and functional properties. Thus, this present review provides an up-to-date overview of advancements in the utilization of microbial β-glucosidases as "Emerging Green Tools" in 21st-century industries. In this regard, focus was placed on the use of recombinant technology, protein engineering, and immobilization techniques targeted at improving the industrial applicability of the enzyme. Furthermore, insights were given into the recent progress made in conventional β-glucosidase production, their industrial applications, as well as the current commercial status-with a focus on the patents.
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Affiliation(s)
- Buka Magwaza
- Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, P. O. Box 1334, Durban, 4000, South Africa.
| | - Ayodeji Amobonye
- Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, P. O. Box 1334, Durban, 4000, South Africa.
| | - Santhosh Pillai
- Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, P. O. Box 1334, Durban, 4000, South Africa.
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Raheja Y, Singh V, Sharma G, Tsang A, Chadha BS. A thermostable and inhibitor resistant β-glucosidase from Rasamsonia emersonii for efficient hydrolysis of lignocellulosics biomass. Bioprocess Biosyst Eng 2024; 47:567-582. [PMID: 38470501 DOI: 10.1007/s00449-024-02988-4] [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: 11/06/2023] [Accepted: 02/20/2024] [Indexed: 03/14/2024]
Abstract
The present study reports a highly thermostable β-glucosidase (GH3) from Rasamsonia emersonii that was heterologously expressed in Pichia pastoris. Extracellular β-glucosidase was purified to homogeneity using single step affinity chromatography with molecular weight of ~ 110 kDa. Intriguingly, the purified enzyme displayed high tolerance to inhibitors mainly acetic acid, formic acid, ferulic acid, vanillin and 5-hydroxymethyl furfural at concentrations exceeding those present in acid steam pretreated rice straw slurry used for hydrolysis and subsequent fermentation in 2G ethanol plants. Characteristics of purified β-glucosidase revealed the optimal activity at 80 °C, pH 5.0 and displayed high thermostability over broad range of temperature 50-70 °C with maximum half-life of ~ 60 h at 50 °C, pH 5.0. The putative transglycosylation activity of β-glucosidase was appreciably enhanced in the presence of methanol as an acceptor. Using the transglycosylation ability of β-glucosidase, the generated low cost mixed glucose disaccharides resulted in the increased induction of R. emersonii cellulase under submerged fermentation. Scaling up the recombinant protein production at fermenter level using temporal feeding approach resulted in maximal β-glucosidase titres of 134,660 units/L. Furthermore, a developed custom made enzyme cocktail consisting of cellulase from R. emersonii mutant M36 supplemented with recombinant β-glucosidase resulted in significantly enhanced hydrolysis of pretreated rice straw slurry from IOCL industries (India). Our results suggest multi-faceted β-glucosidase from R. emersonii can overcome obstacles mainly high cost associated enzyme production, inhibitors that impair the sugar yields and thermal inactivation of enzyme.
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Affiliation(s)
- Yashika Raheja
- Department of Microbiology, Guru Nanak Dev University, Amritsar, 143005, Punjab, India
| | - Varinder Singh
- Department of Microbiology, Guru Nanak Dev University, Amritsar, 143005, Punjab, India
| | - Gaurav Sharma
- Department of Microbiology, Guru Nanak Dev University, Amritsar, 143005, Punjab, India
| | - Adrian Tsang
- Center for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montreal, QC, H4B 1R6, Canada
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Paul S, Parvez SS, Goswami A, Banik A. Exopolysaccharides from agriculturally important microorganisms: Conferring soil nutrient status and plant health. Int J Biol Macromol 2024; 262:129954. [PMID: 38336329 DOI: 10.1016/j.ijbiomac.2024.129954] [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: 03/31/2023] [Revised: 08/10/2023] [Accepted: 02/01/2024] [Indexed: 02/12/2024]
Abstract
A wide variety of microorganisms secretes extracellular polymeric substances or commonly known as exopolysaccharides (EPS), which have been studied to influence plant growth via various mechanisms. EPS-producing microorganisms have been found to have positive effects on plant health such as by facilitating nutrient entrapment in the soil, or by improving soil quality, especially by helping in mitigating various abiotic stress conditions. The various types of microbial polysaccharides allow for the compartmentalization of the microbial community enabling them to endure undressing stress conditions. With the growing population, there is a constant need for developing sustainable agriculture where we could use various PGPR to help the plant cope with various stress conditions and simultaneously enhance the crop yield. These polysaccharides have also found application in various sectors, especially in the biomedical fields, manifesting their potential to act as antitumor drugs, play a significant role in immune evasion, and reveal various therapeutic potentials. These constitute high levels of bioactive polysaccharides which possess a wide range of implementation starting from industrial applications to novel food applications. In this current review, we aim at presenting a comprehensive study of how these microbial extracellular polymeric substances influence agricultural productivity along with their other commercial applications.
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Affiliation(s)
- Sushreeta Paul
- Laboratory of Microbial Interaction, Institute of Health Sciences, Presidency University, Kolkata, West Bengal, India
| | - Sk Soyal Parvez
- Laboratory of Microbial Interaction, Institute of Health Sciences, Presidency University, Kolkata, West Bengal, India
| | - Anusree Goswami
- Laboratory of Microbial Interaction, Institute of Health Sciences, Presidency University, Kolkata, West Bengal, India
| | - Avishek Banik
- Laboratory of Microbial Interaction, Institute of Health Sciences, Presidency University, Kolkata, West Bengal, India.
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Teng Z, Pan X, Liu Y, You J, Zhang H, Zhao Z, Qiao Z, Rao Z. Engineering serine hydroxymethyltransferases for efficient synthesis of L-serine in Escherichia coli. BIORESOURCE TECHNOLOGY 2024; 393:130153. [PMID: 38052329 DOI: 10.1016/j.biortech.2023.130153] [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: 11/13/2023] [Revised: 12/01/2023] [Accepted: 12/02/2023] [Indexed: 12/07/2023]
Abstract
L-serine is a high-value amino acid widely used in the food, medicine, and cosmetic industries. However, the low yield of L-serine has limited its industrial production. In this study, a cellular factory for efficient synthesis of L-serine was obtained by engineering the serine hydroxymethyltransferases (SHMT). Firstly, after screening the SHMT from Alcanivorax dieselolei by genome mining, a mutant AdSHMTE266M with high thermal stability was identified through rational design. Subsequently, an iterative saturating mutant library was constructed by using coevolutionary analysis, and a mutant AdSHMTE160L/E193Q with enzyme activity 1.35 times higher than AdSHMT was identified. Additionally, the target protein AdSHMTE160L/E193Q/E266M was efficiently overexpressed by improving its mRNA stability. Finally, combining the substrate addition strategy and system optimization, the optimized strain BL21/pET28a-AdSHMTE160L/E193Q/E266M-5'UTR-REP3S16 produced 106.06 g/L L-serine, which is the highest production to date. This study provides new ideas and insights for the engineering design of SHMT and the industrial production of L-serine.
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Affiliation(s)
- Zixin Teng
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Xuewei Pan
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Yunran Liu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Jiajia You
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Hengwei Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Zhenqiang Zhao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Zhina Qiao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China
| | - Zhiming Rao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China; Yixing Institute of Food and Biotechnology Co., Ltd, Yixing 214200, China.
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7
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Ouyang B, Wang G, Zhang N, Zuo J, Huang Y, Zhao X. Recent Advances in β-Glucosidase Sequence and Structure Engineering: A Brief Review. Molecules 2023; 28:4990. [PMID: 37446652 DOI: 10.3390/molecules28134990] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/21/2023] [Accepted: 06/23/2023] [Indexed: 07/15/2023] Open
Abstract
β-glucosidases (BGLs) play a crucial role in the degradation of lignocellulosic biomass as well as in industrial applications such as pharmaceuticals, foods, and flavors. However, the application of BGLs has been largely hindered by issues such as low enzyme activity, product inhibition, low stability, etc. Many approaches have been developed to engineer BGLs to improve these enzymatic characteristics to facilitate industrial production. In this article, we review the recent advances in BGL engineering in the field, including the efforts from our laboratory. We summarize and discuss the BGL engineering studies according to the targeted functions as well as the specific strategies used for BGL engineering.
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Affiliation(s)
- Bei Ouyang
- College of Life Science, Jiangxi Normal University, Nanchang 330022, China
| | - Guoping Wang
- College of Life Science, Jiangxi Normal University, Nanchang 330022, China
| | - Nian Zhang
- College of Life Science, Jiangxi Normal University, Nanchang 330022, China
| | - Jiali Zuo
- School of Computer and Information Engineering, Jiangxi Normal University, Nanchang 330022, China
| | - Yunhong Huang
- College of Life Science, Jiangxi Normal University, Nanchang 330022, China
| | - Xihua Zhao
- College of Life Science, Jiangxi Normal University, Nanchang 330022, China
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Wu M, Lv K, Li J, Wu B, He B. Coevolutionary analysis reveals a distal amino acid residue pair affecting the catalytic activity of GH5 processive endoglucanase from Bacillus subtilis BS-5. Biotechnol Bioeng 2022; 119:2105-2114. [PMID: 35438195 DOI: 10.1002/bit.28113] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/05/2022] [Accepted: 04/08/2022] [Indexed: 11/06/2022]
Abstract
EG5C-1, processive endoglucanase from Bacillus subtilis, is a typical bifunctional cellulase with endoglucanase and exoglucanase activities. The engineering of processive endoglucanase focuses on the catalytic pocket or carbohydrate-binding module tailoring based on sequence/structure information. Herein, a computational strategy was applied to identify the desired mutants in the enzyme molecule by evolutionary coupling analysis; subsequently, four residue pairs were selected as evolutionary mutational hotspots. Based on iterative-saturation mutagenesis and subsequent enzymatic activity analysis, a superior mutant K51T/L93T was identified away from the active center. This variant had increased specific activity from 4170 U/µmol of wild-type (WT) to 5678 U/µmol towards CMC-Na and an increase towards the substrate Avicel from 320 U/µmol in WT to 521 U/µmol. In addition, kinetic measurements suggested that superior mutant K51T/L93T had a high substrate affinity (Km ) and a remarkable improvement in catalytic efficiency (kcat /Km ). Furthermore, molecular dynamics simulations revealed that the K51T/L93T mutation altered the spatial conformation at the active site cleft, enhancing the interaction frequency between active site residues and substrate, improving catalytic efficiency and substrate affinity. The current studies provided some perspectives on the effects of distal residue substitution, which might assist in the engineering of processive endoglucanase or other glycoside hydrolases. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Mujunqi Wu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhunan road, Nanjing, 211816, Jiangsu, China
| | - Kemin Lv
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhunan road, Nanjing, 211816, Jiangsu, China
| | - Jiahuang Li
- School of Biopharmacy, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Bin Wu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhunan road, Nanjing, 211816, Jiangsu, China
| | - Bingfang He
- School of Pharmaceutical Sciences, Nanjing Tech University, 30 Puzhunan road, Nanjing, 211816, Jiangsu, China
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Sun N, Liu X, Wang X, Shi H, Zhang H, Li L, Na W, Guan Q. Optimization of fermentation conditions for the production of acidophilic β-glucosidase by Trichoderma reesei S12 from mangrove soil. BIOTECHNOL BIOTEC EQ 2022. [DOI: 10.1080/13102818.2021.1984989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Nan Sun
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Xiaoxuan Liu
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Xuemei Wang
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Huiyu Shi
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Haiwen Zhang
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Lianbin Li
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Wei Na
- Lab of Animal Genetics, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, Haikou, Hainan, P.R.China
| | - Qingfeng Guan
- Lab of Microorganism Resource and Utilization Research, School of Life Sciences, Hainan University, Haikou, Hainan, P.R.China
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Xia W, Bai Y, Shi P. Improving the Substrate Affinity and Catalytic Efficiency of β-Glucosidase Bgl3A from Talaromyces leycettanus JCM12802 by Rational Design. Biomolecules 2021; 11:biom11121882. [PMID: 34944526 PMCID: PMC8699594 DOI: 10.3390/biom11121882] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 12/31/2022] Open
Abstract
Improving the substrate affinity and catalytic efficiency of β-glucosidase is necessary for better performance in the enzymatic saccharification of cellulosic biomass because of its ability to prevent cellobiose inhibition on cellulases. Bgl3A from Talaromyces leycettanus JCM12802, identified in our previous work, was considered a suitable candidate enzyme for efficient cellulose saccharification with higher catalytic efficiency on the natural substrate cellobiose compared with other β-glucosidase but showed insufficient substrate affinity. In this work, hydrophobic stacking interaction and hydrogen-bonding networks in the active center of Bgl3A were analyzed and rationally designed to strengthen substrate binding. Three vital residues, Met36, Phe66, and Glu168, which were supposed to influence substrate binding by stabilizing adjacent binding site, were chosen for mutagenesis. The results indicated that strengthening the hydrophobic interaction between stacking aromatic residue and the substrate, and stabilizing the hydrogen-bonding networks in the binding pocket could contribute to the stabilized substrate combination. Four dominant mutants, M36E, M36N, F66Y, and E168Q with significantly lower Km values and 1.4–2.3-fold catalytic efficiencies, were obtained. These findings may provide a valuable reference for the design of other β-glucosidases and even glycoside hydrolases.
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Affiliation(s)
- Wei Xia
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100081, China;
| | - Yingguo Bai
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Correspondence: (Y.B.); (P.S.)
| | - Pengjun Shi
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100081, China;
- Correspondence: (Y.B.); (P.S.)
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11
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Comparative Secretomics Analysis Reveals the Major Components of Penicillium oxalicum 16 and Trichoderma reesei RUT-C30. Microorganisms 2021; 9:microorganisms9102042. [PMID: 34683363 PMCID: PMC8538001 DOI: 10.3390/microorganisms9102042] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 09/16/2021] [Accepted: 09/24/2021] [Indexed: 11/23/2022] Open
Abstract
In this study, the major secretome components of Penicillium oxalicum 16 and Trichoderma reesei RUT-C30 under wheat bran (WB) and rice straw (RS) solid-state fermentation were systematically analyzed. The activities of the major components, e.g., cellulase, hemicellulase, and amylase, were consistent with their abundance in the secretomes. P. oxalicum 16 secreted more abundant glycoside hydrolases than T. reesei RUT-C30. The main up-regulated proteins from the induction of WB, compared with that from RS, were amylase, pectinase, and protease, whereas the main down-regulated enzymes were cellulase, hemicellulase, swollenin, and lytic polysaccharide monooxygenase (LPMO). Specifically, WB induced more β-1,4-glucosidases, namely, S8B0F3 (UniProt ID), and A0A024RWA5 than RS, but RS induced more β-1,4-exoglucanases and β-1,4-endoglucanases, namely, A0A024RXP8, A024SH76, S7B6D6, S7ZP52, A024SH20, A024S2H5, S8BGM3, S7ZX22, and S8AIJ2. The P. oxalicum 16 xylanases S8AH74 and S7ZA57 were the major components responsible for degrading soluble xylan, and S8BDN2 probably acted on solid-state hemicellulose instead of soluble xylan. The main hemicellulase component of T. reesei RUT-C30 in RS was the xyloglucanase A0A024S9Z6 with an abundance of 16%, but T. reesei RUT-C30 lacked the hemicellulase mannanase and had a small amount of the hemicellulase xylanase. P. oxalicum 16 produced more amylase than T. reesei RUT-C30, and the results suggest amylase S7Z6T2 may degrade soluble starch. The percentage of the glucoamylase S8B6D7 did not significantly change, and reached an average abundance of 5.5%. The major auxiliary degradation enzymes of P. oxalicum 16 were LPMOs S7Z716 and S7ZPW1, whereas those of T. reesei RUT-C30 were swollenin and LPMOs A0A024SM10, A0A024SFJ2, and A0A024RZP7.
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Unconventional β-Glucosidases: A Promising Biocatalyst for Industrial Biotechnology. Appl Biochem Biotechnol 2021; 193:2993-3016. [PMID: 33871765 DOI: 10.1007/s12010-021-03568-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 04/08/2021] [Indexed: 10/21/2022]
Abstract
β-Glucosidases primarily catalyze removal of terminal glucosyl residues from a variety of glucoconjugates and also perform transglycosylation and reverse hydrolysis. These catalytic properties can be readily exploited for degradation of lignocellulosic biomass as well as for pharmaceutical, food and flavor industries. β-Glucosidases have been either isolated in the native form from the producer organism or recombinantly expressed and gaged for their biochemical properties and substrate specificities. Although almond and Aspergillus niger have been instantly recognizable sources of β-glucosidases utilized for various applications, an intricate pool of novel β-glucosidases from different sources can provide their potent replacements. Moreover, one can envisage the better efficacy of these novel candidates in biofuel and biorefinery industries facilitating efficient degradation of biomass. This article reviews properties of the novel β-glucosidases such as glucose tolerance and activation, substrate specificity, and thermostability which can be useful for their applications in lignocellulose degradation, food industry, and pharmaceutical industry in comparison with the β-glucosidases from the conventional sources. Such β-glucosidases have potential for encouraging white biotechnology.
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