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de Andrades D, Alnoch RC, Alves GS, Salgado JCS, Almeida PZ, Berto GL, Segato F, Ward RJ, Buckeridge MS, Polizeli MDLTM. Recombinant GH3 β-glucosidase stimulated by xylose and tolerant to furfural and 5-hydroxymethylfurfural obtained from Aspergillus nidulans. BIORESOUR BIOPROCESS 2024; 11:77. [PMID: 39073555 PMCID: PMC11286919 DOI: 10.1186/s40643-024-00784-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/03/2024] [Indexed: 07/30/2024] Open
Abstract
The β-glucosidase gene from Aspergillus nidulans FGSC A4 was cloned and overexpressed in the A. nidulans A773. The resulting purified β-glucosidase, named AnGH3, is a monomeric enzyme with a molecular weight of approximately 80 kDa, as confirmed by SDS-PAGE. Circular dichroism further validated its unique canonical barrel fold (β/α), a feature also observed in the 3D homology model of AnGH3. The most striking aspect of this recombinant enzyme is its robustness, as it retained 100% activity after 24 h of incubation at 45 and 50 ºC and pH 6.0. Even at 55 °C, it maintained 72% of its enzymatic activity after 6 h of incubation at the same pH. The kinetic parameters Vmax, KM, and Kcat/KM for ρ-nitrophenyl-β-D-glucopyranoside (ρNPG) and cellobiose were also determined. Using ρNPG, the enzyme demonstrated a Vmax of 212 U mg - 1, KM of 0.0607 mmol L - 1, and Kcat/KM of 4521 mmol L - 1 s - 1 when incubated at pH 6.0 and 65 °C. The KM, Vmax, and Kcat/KM using cellobiose were 2.7 mmol L - 1, 57 U mg - 1, and 27 mmol -1 s - 1, respectively. AnGH3 activity was significantly enhanced by xylose and ethanol at concentrations up to 1.5 mol L - 1 and 25%, respectively. Even in challenging conditions, at 65 °C and pH 6.0, the enzyme maintained its activity, retaining 100% and 70% of its initial activity in the presence of 200 mmol L - 1 furfural and 5-hydroxymethylfurfural (HMF), respectively. The potential of this enzyme was further demonstrated by its application in the saccharification of the forage grass Panicum maximum, where it led to a 48% increase in glucose release after 24 h. These unique characteristics, including high catalytic performance, good thermal stability in hydrolysis temperature, and tolerance to elevated concentrations of ethanol, D-xylose, furfural, and HMF, position this recombinant enzyme as a promising tool in the hydrolysis of lignocellulosic biomass as part of an efficient multi-enzyme cocktail, thereby opening new avenues in the field of biotechnology and enzymology.
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Affiliation(s)
- Diandra de Andrades
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
| | - Robson C Alnoch
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
- Department of Biochemistry and Immunology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Gabriela S Alves
- Department of Biochemistry and Immunology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
- Laboratory of Enzymology and Molecular Biology of Microorganisms, Institute of Biology, Campinas State University (UNICAMP), Campinas, 13083-970, SP, Brazil
| | - Jose C S Salgado
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
- Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
| | - Paula Z Almeida
- Department of Biochemistry and Immunology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil
| | - Gabriela Leila Berto
- Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Lorena, 12602-810, Brazil
| | - Fernando Segato
- Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Lorena, 12602-810, Brazil
| | - Richard J Ward
- Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
| | | | - Maria de Lourdes T M Polizeli
- Department of Biology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14040-901, Brazil.
- Department of Biochemistry and Immunology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, 14049-900, Brazil.
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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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Khlebodarova TM, Bogacheva NV, Zadorozhny AV, Bryanskaya AV, Vasilieva AR, Chesnokov DO, Pavlova EI, Peltek SE. Komagataella phaffii as a Platform for Heterologous Expression of Enzymes Used for Industry. Microorganisms 2024; 12:346. [PMID: 38399750 PMCID: PMC10892927 DOI: 10.3390/microorganisms12020346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/01/2024] [Accepted: 02/03/2024] [Indexed: 02/25/2024] Open
Abstract
In the 1980s, Escherichia coli was the preferred host for heterologous protein expression owing to its capacity for rapid growth in complex media; well-studied genetics; rapid and direct transformation with foreign DNA; and easily scalable fermentation. Despite the relative ease of use of E. coli for achieving the high expression of many recombinant proteins, for some proteins, e.g., membrane proteins or proteins of eukaryotic origin, this approach can be rather ineffective. Another microorganism long-used and popular as an expression system is baker's yeast, Saccharomyces cerevisiae. In spite of a number of obvious advantages of these yeasts as host cells, there are some limitations on their use as expression systems, for example, inefficient secretion, misfolding, hyperglycosylation, and aberrant proteolytic processing of proteins. Over the past decade, nontraditional yeast species have been adapted to the role of alternative hosts for the production of recombinant proteins, e.g., Komagataella phaffii, Yarrowia lipolytica, and Schizosaccharomyces pombe. These yeast species' several physiological characteristics (that are different from those of S. cerevisiae), such as faster growth on cheap carbon sources and higher secretion capacity, make them practical alternative hosts for biotechnological purposes. Currently, the K. phaffii-based expression system is one of the most popular for the production of heterologous proteins. Along with the low secretion of endogenous proteins, K. phaffii efficiently produces and secretes heterologous proteins in high yields, thereby reducing the cost of purifying the latter. This review will discuss practical approaches and technological solutions for the efficient expression of recombinant proteins in K. phaffii, mainly based on the example of enzymes used for the feed industry.
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Affiliation(s)
- Tamara M. Khlebodarova
- Kurchatov Genomic Center at Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.M.K.); (N.V.B.); (A.V.Z.); (A.V.B.); (A.R.V.)
- Laboratory Molecular Biotechnologies of the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Natalia V. Bogacheva
- Kurchatov Genomic Center at Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.M.K.); (N.V.B.); (A.V.Z.); (A.V.B.); (A.R.V.)
- Laboratory Molecular Biotechnologies of the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Andrey V. Zadorozhny
- Kurchatov Genomic Center at Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.M.K.); (N.V.B.); (A.V.Z.); (A.V.B.); (A.R.V.)
- Laboratory Molecular Biotechnologies of the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Alla V. Bryanskaya
- Kurchatov Genomic Center at Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.M.K.); (N.V.B.); (A.V.Z.); (A.V.B.); (A.R.V.)
- Laboratory Molecular Biotechnologies of the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Asya R. Vasilieva
- Kurchatov Genomic Center at Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.M.K.); (N.V.B.); (A.V.Z.); (A.V.B.); (A.R.V.)
- Laboratory Molecular Biotechnologies of the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Danil O. Chesnokov
- Sector of Genetics of Industrial Microorganisms of Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (D.O.C.); (E.I.P.)
| | - Elena I. Pavlova
- Sector of Genetics of Industrial Microorganisms of Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (D.O.C.); (E.I.P.)
| | - Sergey E. Peltek
- Kurchatov Genomic Center at Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.M.K.); (N.V.B.); (A.V.Z.); (A.V.B.); (A.R.V.)
- Laboratory Molecular Biotechnologies of the Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
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Erkanli ME, El-Halabi K, Kim JR. Exploring the diversity of β-glucosidase: Classification, catalytic mechanism, molecular characteristics, kinetic models, and applications. Enzyme Microb Technol 2024; 173:110363. [PMID: 38041879 DOI: 10.1016/j.enzmictec.2023.110363] [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: 09/25/2023] [Revised: 11/17/2023] [Accepted: 11/18/2023] [Indexed: 12/04/2023]
Abstract
High-value chemicals and energy-related products can be produced from biomass. Biorefinery technology offers a sustainable and cost-effective method for this high-value conversion. β-glucosidase is one of the key enzymes in biorefinery processes, catalyzing the production of glucose from aryl-glycosides and cello-oligosaccharides via the hydrolysis of β-glycosidic bonds. Although β-glucosidase plays a critical catalytic role in the utilization of cellulosic biomass, its efficacy is often limited by substrate or product inhibitions, low thermostability, and/or insufficient catalytic activity. To provide a detailed overview of β-glucosidases and their benefits in certain desired applications, we collected and summarized extensive information from literature and public databases, covering β-glucosidases in different glycosidase hydrolase families and biological kingdoms. These β-glucosidases show differences in amino acid sequence, which are translated into varying degrees of the molecular properties critical in enzymatic applications. This review describes studies on the diversity of β-glucosidases related to the classification, catalytic mechanisms, key molecular characteristics, kinetics models, and applications, and highlights several β-glucosidases displaying high stability, activity, and resistance to glucose inhibition suitable for desired biotechnological applications.
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Affiliation(s)
- Mehmet Emre Erkanli
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY 11201, United States
| | - Khalid El-Halabi
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY 11201, United States
| | - Jin Ryoun Kim
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY 11201, United States.
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Okereke OE, Gupta M, Ogunyewo OA, Sharma K, Kapoor S, Sinha T, Yazdani SS. Profiling of the β-glucosidases identified in the genome of Penicillium funiculosum: insights from genomics, transcriptomics, proteomics, and homology-modeling studies. Appl Environ Microbiol 2023; 89:e0070423. [PMID: 37610233 PMCID: PMC10537656 DOI: 10.1128/aem.00704-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 07/14/2023] [Indexed: 08/24/2023] Open
Abstract
The enzymatic conversion of lignocellulosic biomass to bioethanol depends on efficient enzyme systems with β-glucosidase as one of the key components. In this study, we performed in-depth profiling of the various β-glucosidases present in the genome of the hypercellulolytic fungus Penicillium funiculosum using genomics, transcriptomics, proteomics, and molecular dynamics simulation approaches. Of the eight β-glucosidase genes identified in the P. funiculosum genome, three were predicted to be extracellular based on signal peptide prediction and abundance in the secretome. Among the three secreted β-glucosidases, two belonged to the GH3 family and one belonged to the GH1 family. Homology models of these proteins predicted a deep and narrow active site for the GH3 β-glucosidases (PfBgl3A and PfBgl3B) and a shallow open active site for the GH1 β-glucosidase (PfBgl1A). The enzymatic assays indicated that P. funiculosum-secreted proteins showed high β-glucosidase activities with prominent bands on the 4-methylumbelliferyl β-D-glucopyranoside zymogram. To understand the contributory effects of each of the three secreted β-glucosidases (PfBgls), the corresponding gene was deleted separately, and the effect of the deletion on the β-glucosidase activity of the secretome was examined. Although not the most abundant, PfBgl3A was found to be one of the most important β-glucosidases, as evidenced by a 42% reduction in β-glucosidase activity in the ΔPfBgl3A strain. Our results advance the understanding of the genetic and biochemical nature of all β-glucosidases produced by P. funiculosum and pave the way to design a superior biocatalyst for the hydrolysis of lignocellulosic biomass. IMPORTANCE Commercially available cellulases are primarily produced from Trichoderma reesei. However, external supplementation of the cellulase cocktail from this host with exogenous β-glucosidase is often required to achieve the desired optimal saccharification of cellulosic feedstocks. This challenge has led to the exploration of other cellulase-producing strains. The nonmodel hypercellulolytic fungus Penicillium funiculosum has been studied in recent times and identified as a promising source of industrial cellulases mainly due to its ability to produce a balanced concoction of cellulolytic enzymes, including β-glucosidases. Various genetic interventions targeted at strain improvement for cellulase production have been performed; however, the β-glucosidases of this strain have remained largely understudied. This study, therefore, reports profiling of all eight β-glucosidases of P. funiculosum via molecular and computational approaches. The results of this study provide useful insights that will establish the background for future engineering strategies to transform this fungus into an industrial workhorse.
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Affiliation(s)
- Omoaruemike Ebele Okereke
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- Biotechnology Advanced Research Centre, Sheda Science and Technology Complex (SHESTCO), Abuja, Nigeria
| | - Mayank Gupta
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Olusola A. Ogunyewo
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Kanika Sharma
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Sonal Kapoor
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Tulika Sinha
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Syed Shams Yazdani
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
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Sun N, Liu X, Zhang B, Wang X, Na W, Tan Z, Li X, Guan Q. Characterization of a novel recombinant halophilic β-glucosidase of Trichoderma harzianum derived from Hainan mangrove. BMC Microbiol 2022; 22:185. [PMID: 35902815 PMCID: PMC9331182 DOI: 10.1186/s12866-022-02596-w] [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: 12/26/2021] [Accepted: 07/07/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND β-glucosidase is an important biomass-degrading enzyme and plays a vital role in generating renewable biofuels through enzymatic saccharification. In this study, we analyzed the transcriptome of Trichoderma harzianum HTASA derived from Hainan mangrove and identified a new gene encoding β-glucosidase Bgl3HB. And the biochemically characterization of β-glucosidase activity was performed. RESULTS Bgl3HB showed substantial catalytic activity in the pH range of 3.0-5.0 and at temperatures of 40 ℃-60 ℃. The enzyme was found quite stable at 50 ℃ with a loss of only 33.4% relative activity after 240 min of heat exposure. In addition, all tested metal ions were found to promote the enzyme activity. The β-glucosidase activity of Bgl3HB was enhanced by 2.12-fold of its original activity in the presence of 5 M NaCl. Surprisingly, Bgl3HB also showed a remarkable ability to hydrolyze laminarin compared to other measured substrates. Enzyme efficiency was examined in the sugarcane bagasse saccharification processes, in which Bgl3HB with 5 M NaCl worked better supplementing Celluclast 1.5L than the commercial Novozyme 188 ascertained it as an admirably suited biocatalyst for the utilization of agricultural waste. In this work, this is the first report of a halophilic β-glucosidase from Trichoderma harzianum, and represents the β-glucosidase with the highest known NaCl activation concentration. And adding 5 M NaCl could enhance saccharification performance even better than commercial cellulase. CONCLUSIONS These results show that Bgl3HB has great promise as a highly stable and highly efficient cellulase with important future applications in the industrial production of biofuels.
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Affiliation(s)
- Nan Sun
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China
| | - Xiaoxuan Liu
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China
| | - Bingxi Zhang
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China
| | - Xuemei Wang
- Lab of Animal Nutrition, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China.
| | - Wei Na
- Lab of Animal Genetics, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China
| | - Zhen Tan
- Lab of Animal Genetics, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China
| | - Xiaochun Li
- Lab of Animal Genetics, Reproduction & Breeding, College of Animal Science and Technology, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China
| | - Qingfeng Guan
- Lab of Microorganism Resource and Utilization Research, School of Life Sciences, Hainan University, No.58 Renmin Avenue, Meilan, Haikou, 570228, P. R. China
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Crystal structure of metagenomic β-glycosidase MeBglD2 in complex with various saccharides. Appl Microbiol Biotechnol 2022; 106:4539-4551. [PMID: 35723691 DOI: 10.1007/s00253-022-12018-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/23/2022] [Accepted: 05/27/2022] [Indexed: 11/02/2022]
Abstract
Metagenomic MeBglD2 is a glycoside hydrolase family 1 (GH1) β-glycosidase that has β-glucosidase, β-fucosidase, and β-galactosidase activities, and is highly activated in the presence of monosaccharides and disaccharides. The β-glucosidase activity of MeBglD2 increases in a cellobiose concentration-dependent manner and is not inhibited by a high concentration of D-glucose or cellobiose. Previously, we solved the crystal structure of MeBglD2 and designed a thermostable mutant; however, the mechanism of substrate recognition of MeBglD2 remains poorly understood. In this paper, we report the X-ray crystal structures of MeBglD2 complexed with various saccharides, such as D-glucose, D-xylose, cellobiose, and maltose. The results showed that subsite - 1 of MeBglD2, which contained two catalytic glutamate residues (a nucleophilic Glu356 and an acid/base Glu170) was common to other GH1 enzymes, but the positive subsites (+ 1 and + 2) had different binding modes depending on the type of sugar. Three residues (Glu183, Asn227, and Asn229), located at the positive subsites of MeBglD2, were involved in substrate specificity toward cellobiose and/or chromogenic substrates in the presence of additive sugars. The docking simulation of MeBglD2-cellobiose indicated that Asn229 and Trp329 play important roles in the recognition of + 1 D-glucose in cellobiose. Our findings provide insights into the unique substrate recognition mechanism of GH1, which can incorporate a variety of saccharides into its positive subsites. KEY POINTS: • Metagenomic glycosidase, MeBglD2, recognizes various saccharides • Structures of metagenomic MeBglD2 complexed with various saccharides are determined • MeBglD2 has a unique substrate recognition mechanism at the positive subsites.
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Li X, Xia X, Wang Z, Wang Y, Dai Y, Yin L, Xu Z, Zhou J. Cloning and expression of
Lactobacillus brevis
β‐glucosidase
and its effect on the aroma of strawberry wine. J FOOD PROCESS PRES 2022. [DOI: 10.1111/jfpp.16368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Xiaonan Li
- School of Food and Biological Engineering, Jiangsu University Zhenjiang China
- Institute of Agro‐Product Processing, Jiangsu Academy of Agricultural Sciences Nanjing China
| | - Xiudong Xia
- School of Food and Biological Engineering, Jiangsu University Zhenjiang China
- Institute of Agro‐Product Processing, Jiangsu Academy of Agricultural Sciences Nanjing China
| | - Zhe Wang
- Institute of Agro‐Product Processing, Jiangsu Academy of Agricultural Sciences Nanjing China
- College of Food Science and Technology, Nanjing Agricultural University Nanjing China
| | - Yun Wang
- School of Food and Biological Engineering, Jiangsu University Zhenjiang China
| | - Yiqiang Dai
- Institute of Agro‐Product Processing, Jiangsu Academy of Agricultural Sciences Nanjing China
- College of Food Science and Technology, Nanjing Agricultural University Nanjing China
| | - Liqing Yin
- Institute of Agro‐Product Processing, Jiangsu Academy of Agricultural Sciences Nanjing China
- College of Food Science and Technology, Nanjing Agricultural University Nanjing China
| | - Zhuang Xu
- School of Food and Biological Engineering, Jiangsu University Zhenjiang China
- Institute of Agro‐Product Processing, Jiangsu Academy of Agricultural Sciences Nanjing China
| | - Jianzhong Zhou
- School of Food and Biological Engineering, Jiangsu University Zhenjiang China
- Institute of Agro‐Product Processing, Jiangsu Academy of Agricultural Sciences Nanjing China
- College of Food Science and Technology, Nanjing Agricultural University Nanjing China
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Prieto A, de Eugenio L, Méndez-Líter JA, Nieto-Domínguez M, Murgiondo C, Barriuso J, Bejarano-Muñoz L, Martínez MJ. Fungal glycosyl hydrolases for sustainable plant biomass valorization: Talaromyces amestolkiae as a model fungus. Int Microbiol 2021; 24:545-558. [PMID: 34417929 DOI: 10.1007/s10123-021-00202-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 11/26/2022]
Abstract
As the main decomposers and recyclers in nature, fungi secrete complex mixtures of extracellular enzymes for degradation of plant biomass, which is essential for mobilization of the organic carbon fixed by the photosynthesis in vegetal cells. Biotechnology can emulate the closed natural biological cycles, using lignocellulosic biomass as a renewable resource and lignocellulolytic fungal enzymes as catalysts to sustainably produce consumer goods. Cellulose and hemicellulose are the major polysaccharides on Earth, and the main enzymes involved in their hydrolytic depolymerization are cellulases (endoglucanases, cellobiohydrolases, and β-glucosidases) and hemicellulases (mainly endoxylanases and β-xylosidases). This work will focus on the enzymes secreted by the filamentous ascomycete Talaromyces amestolkiae and on some of their biotechnological applications. Their excellent hydrolytic activity was demonstrated by the partial degradation of xylans to prebiotic oligosaccharides by the endoxylanase XynN, or by the saccharification of lignocellulosic wastes to monosaccharides (fermentable to ethanol) either by the whole secretomes or by isolated enzymes used as supplements of commercial cocktails. However, apart from their expected hydrolytic activity, some of the β-glycosidases produced by this strain catalyze the transfer of a sugar molecule to specific aglycons by transglycosylation. As the synthesis of customized glycoconjugates is a major goal for biocatalysis, mutant variants of the β-xyloxidase BxTW1 and the ß-glucosidases BGL-1 and BGL-2 were obtained by directed mutagenesis, substantially improving the regioselective production yields of bioactive glycosides since they showed reduced or null hydrolytic activity.
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Affiliation(s)
- Alicia Prieto
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain.
| | - Laura de Eugenio
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain
| | - Juan A Méndez-Líter
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain
| | - Manuel Nieto-Domínguez
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain
| | - Carlos Murgiondo
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain
| | - Jorge Barriuso
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain
| | - Lara Bejarano-Muñoz
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain
| | - María Jesús Martínez
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), C/ Ramiro de Maeztu 9, 28022, Madrid, Spain.
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Thermostable cellulose saccharifying microbial enzymes: Characteristics, recent advances and biotechnological applications. Int J Biol Macromol 2021; 188:226-244. [PMID: 34371052 DOI: 10.1016/j.ijbiomac.2021.08.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/19/2021] [Accepted: 08/03/2021] [Indexed: 12/12/2022]
Abstract
Cellulases play a promising role in the bioconversion of renewable lignocellulosic biomass into fermentable sugars which are subsequently fermented to biofuels and other value-added chemicals. Besides biofuel industries, they are also in huge demand in textile, detergent, and paper and pulp industries. Low titres of cellulase production and processing are the main issues that contribute to high enzyme cost. The success of ethanol-based biorefinery depends on high production titres and the catalytic efficiency of cellulases functional at elevated temperatures with acid/alkali tolerance and the low cost. In view of their wider application in various industrial processes, stable cellulases that are active at elevated temperatures in the acidic-alkaline pH ranges, and organic solvents and salt tolerance would be useful. This review provides a recent update on the advances made in thermostable cellulases. Developments in their sources, characteristics and mechanisms are updated. Various methods such as rational design, directed evolution, synthetic & system biology and immobilization techniques adopted in evolving cellulases with ameliorated thermostability and characteristics are also discussed. The wide range of applications of thermostable cellulases in various industrial sectors is described.
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Mariano D, Pantuza N, Santos LH, Rocha REO, de Lima LHF, Bleicher L, de Melo-Minardi RC. Glutantβase: a database for improving the rational design of glucose-tolerant β-glucosidases. BMC Mol Cell Biol 2020; 21:50. [PMID: 32611314 PMCID: PMC7329481 DOI: 10.1186/s12860-020-00293-y] [Citation(s) in RCA: 5] [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: 12/16/2019] [Accepted: 06/22/2020] [Indexed: 11/22/2022] Open
Abstract
Β-glucosidases are key enzymes used in second-generation biofuel production. They act in the last step of the lignocellulose saccharification, converting cellobiose in glucose. However, most of the β-glucosidases are inhibited by high glucose concentrations, which turns it a limiting step for industrial production. Thus, β-glucosidases have been targeted by several studies aiming to understand the mechanism of glucose tolerance, pH and thermal resistance for constructing more efficient enzymes. In this paper, we present a database of β-glucosidase structures, called Glutantβase. Our database includes 3842 GH1 β-glucosidase sequences collected from UniProt. We modeled the sequences by comparison and predicted important features in the 3D-structure of each enzyme. Glutantβase provides information about catalytic and conserved amino acids, residues of the coevolution network, protein secondary structure, and residues located in the channel that guides to the active site. We also analyzed the impact of beneficial mutations reported in the literature, predicted in analogous positions, for similar enzymes. We suggested these mutations based on six previously described mutants that showed high catalytic activity, glucose tolerance, or thermostability (A404V, E96K, H184F, H228T, L441F, and V174C). Then, we used molecular docking to verify the impact of the suggested mutations in the affinity of protein and ligands (substrate and product). Our results suggest that only mutations based on the H228T mutant can reduce the affinity for glucose (product) and increase affinity for cellobiose (substrate), which indicates an increment in the resistance to product inhibition and agrees with computational and experimental results previously reported in the literature. More resistant β-glucosidases are essential to saccharification in industrial applications. However, thermostable and glucose-tolerant β-glucosidases are rare, and their glucose tolerance mechanisms appear to be related to multiple and complex factors. We gather here, a set of information, and made predictions aiming to provide a tool for supporting the rational design of more efficient β-glucosidases. We hope that Glutantβase can help improve second-generation biofuel production. Glutantβase is available at http://bioinfo.dcc.ufmg.br/glutantbase .
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Affiliation(s)
- Diego Mariano
- Laboratory of Bioinformatics and Systems. Department of Computer Science, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil.
| | - Naiara Pantuza
- Laboratory of Bioinformatics and Systems. Department of Computer Science, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil
| | - Lucianna H Santos
- Laboratory of Bioinformatics and Systems. Department of Computer Science, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil
| | - Rafael E O Rocha
- Laboratory of Bioinformatics and Systems. Department of Computer Science, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil
| | - Leonardo H F de Lima
- Laboratory of Molecular Modelling and Bioinformatics (LAMMB), Department of Physical and Biological Sciences, Universidade Federal de São João Del-Rei, Campus Sete Lagoas, Sete Lagoas, 35701-970, Brazil
| | - Lucas Bleicher
- Protein Computational Biology Laboratory, Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil
| | - Raquel Cardoso de Melo-Minardi
- Laboratory of Bioinformatics and Systems. Department of Computer Science, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil.
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Méndez-Líter JA, Nieto-Domínguez M, Fernández de Toro B, González Santana A, Prieto A, Asensio JL, Cañada FJ, de Eugenio LI, Martínez MJ. A glucotolerant β-glucosidase from the fungus Talaromyces amestolkiae and its conversion into a glycosynthase for glycosylation of phenolic compounds. Microb Cell Fact 2020; 19:127. [PMID: 32522206 PMCID: PMC7288487 DOI: 10.1186/s12934-020-01386-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 06/04/2020] [Indexed: 12/23/2022] Open
Abstract
Background The interest for finding novel β-glucosidases that can improve the yields to produce second-generation (2G) biofuels is still very high. One of the most desired features for these enzymes is glucose tolerance, which enables their optimal activity under high-glucose concentrations. Besides, there is an additional focus of attention on finding novel enzymatic alternatives for glycoside synthesis, for which a mutated version of glycosidases, named glycosynthases, has gained much interest in recent years. Results In this work, a glucotolerant β-glucosidase (BGL-1) from the ascomycete fungus Talaromyces amestolkiae has been heterologously expressed in Pichia pastoris, purified, and characterized. The enzyme showed good efficiency on p-nitrophenyl glucopyranoside (pNPG) (Km= 3.36 ± 0.7 mM, kcat= 898.31 s−1), but its activity on cellooligosaccharides, the natural substrates of these enzymes, was much lower, which could limit its exploitation in lignocellulose degradation applications. Interestingly, when examining the substrate specificity of BGL-1, it showed to be more active on sophorose, the β-1,2 disaccharide of glucose, than on cellobiose. Besides, the transglycosylation profile of BGL-1 was examined, and, for expanding its synthetic capacities, it was converted into a glycosynthase. The mutant enzyme, named BGL-1-E521G, was able to use α-d-glucosyl-fluoride as donor in glycosylation reactions, and synthesized glucosylated derivatives of different pNP-sugars in a regioselective manner, as well as of some phenolic compounds of industrial interest, such as epigallocatechin gallate (EGCG). Conclusions In this work, we report the characterization of a novel glucotolerant 1,2-β-glucosidase, which also has a considerable activity on 1,4-β-glucosyl bonds, that has been cloned in P. pastoris, produced, purified and characterized. In addition, the enzyme was converted into an efficient glycosynthase, able to transfer glucose molecules to a diversity of acceptors for obtaining compounds of interest. The remarkable capacities of BGL-1 and its glycosynthase mutant, both in hydrolysis and synthesis, suggest that it could be an interesting tool for biotechnological applications.
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Affiliation(s)
- Juan Antonio Méndez-Líter
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Manuel Nieto-Domínguez
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Beatriz Fernández de Toro
- Department of Chemical and Physical Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Andrés González Santana
- Glycochemistry and Molecular Recognition Group, Instituto de Química Orgánica General (IQOG-CSIC), Calle Juan de la Cierva, 3, 28006, Madrid, Spain
| | - Alicia Prieto
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Juan Luis Asensio
- Glycochemistry and Molecular Recognition Group, Instituto de Química Orgánica General (IQOG-CSIC), Calle Juan de la Cierva, 3, 28006, Madrid, Spain
| | - Francisco Javier Cañada
- Department of Chemical and Physical Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Laura Isabel de Eugenio
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - María Jesús Martínez
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain.
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Yang H, Cai G, Lu J, Gómez Plaza E. The production and application of enzymes related to the quality of fruit wine. Crit Rev Food Sci Nutr 2020; 61:1605-1615. [PMID: 32423236 DOI: 10.1080/10408398.2020.1763251] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Grape wine is the most widely consumed fruit wine in the world. With the increasing diversification of consumers' needs, the variety of fruit wines in the market is becoming more and more abundant. Whether it is the production of grape wine or other fruit wines these processes are inseparable from the participation of enzymes. The quality of these wines is closely related to the application of enzymes in the winemaking process. Enzymes are involved in pretreatment, fermentation, filtration, flavoring, aging and storage of fruit wines. This review systematically illustrated the role of pectinase, β-glucanase, β-glucosidase, glucose oxidase, lysozyme, protease, tannase and urease in the production of wines and their current production status and also provided a theoretical basis for better application of various enzymes in the production of various fruit wines. This knowledge could be great significance to improve the quality of fruit wines and reduce the production costs in the fruit wine industry.
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Affiliation(s)
- Hua Yang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, P. R. China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Wuxi, P. R. China.,School of Biotechnology, Jiangnan University, Wuxi, P. R. China.,School of Food Science and Technology, University of Murcia, Murcia, Spain
| | - Guolin Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, P. R. China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Wuxi, P. R. China.,School of Biotechnology, Jiangnan University, Wuxi, P. R. China
| | - Jian Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, P. R. China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Wuxi, P. R. China.,School of Biotechnology, Jiangnan University, Wuxi, P. R. China
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Zhang X, Ma B, Liu J, Chen X, Li S, Su E, Gao L, Li H. β-Glucosidase genes differentially expressed during composting. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:174. [PMID: 33088344 PMCID: PMC7570026 DOI: 10.1186/s13068-020-01813-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 10/07/2020] [Indexed: 05/06/2023]
Abstract
BACKGROUND Cellulose degradation by cellulase is brought about by complex communities of interacting microorganisms, which significantly contribute to the cycling of carbon on a global scale. β-Glucosidase (BGL) is the rate-limiting enzyme in the cellulose degradation process. Thus, analyzing the expression of genes involved in cellulose degradation and regulation of BGL gene expression during composting will improve the understanding of the cellulose degradation mechanism. Based on our previous research, we hypothesized that BGL-producing microbial communities differentially regulate the expression of glucose-tolerant BGL and non-glucose-tolerant BGL to adapt to the changes in cellulose degradation conditions. RESULTS To confirm this hypothesis, the structure and function of functional microbial communities involved in cellulose degradation were investigated by metatranscriptomics and a DNA library search of the GH1 family of BGLs involved in natural and inoculated composting. Under normal conditions, the group of non-glucose-tolerant BGL genes exhibited higher sensitivity to regulation than the glucose-tolerant BGL genes, which was suppressed during the composting process. Compared with the expression of endoglucanase and exoglucanase, the functional microbial communities exhibited a different transcriptional regulation of BGL genes during the cooling phase of natural composting. BGL-producing microbial communities upregulated the expression of glucose-tolerant BGL under carbon catabolite repression due to the increased glucose concentration, whereas the expression of non-glucose-tolerant BGL was suppressed. CONCLUSION Our results support the hypothesis that the functional microbial communities use multiple strategies of varying effectiveness to regulate the expression of BGL genes to facilitate adaptation to environmental changes.
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Affiliation(s)
- Xinyue Zhang
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Bo Ma
- School of Animal Medicine, Northeast Agricultural University, Harbin, 150030 China
- Northeastern Science Inspection Station, China Ministry of Agriculture Key Laboratory of Animal Pathogen Biology, Harbin, 150030 China
| | - Jiawen Liu
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Xiehui Chen
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Shanshan Li
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Erlie Su
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Liyuan Gao
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
| | - Hongtao Li
- College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, 150030 China
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Molecular Insights into FaEG1, a Strawberry Endoglucanase Enzyme Expressed during Strawberry Fruit Ripening. PLANTS 2019; 8:plants8060140. [PMID: 31141938 PMCID: PMC6631567 DOI: 10.3390/plants8060140] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 05/18/2019] [Accepted: 05/25/2019] [Indexed: 01/04/2023]
Abstract
The endo-β-1,4-glucanases (EGs) that belong to the glycosyl hydrolase family 9 (GH9) have roles in cell wall synthesis, remodeling and degradation. Previous studies have suggested that EGs may play a key role in the ripening of different fruits including strawberries. In this study, we used reverse-transcription quantitative polymerase chain reaction (RT-qPCR) assays to determine the transcript accumulation of an endo-β-1,4-glucanase (FaEG1) during fruit development in two different strawberry ‘Camarosa’ and ‘Monterey’ with contrasting softening ratios. Phylogenetic analyses suggest that FaEG1 belongs to the α group of the GH9 family with other proteins previously described with roles in elongation, abscission and ripening. Comparative modeling was used to obtain the FaEG1 structure. The model displays a α-barrel–type structure that is typical of the GH9 enzyme family, and comprises 12 α-helices, 2 310 helices and 6 β-sheets. The catalytic residues were oriented to the solvent in the middle of an open groove. Protein–ligand interactions were explored with cellulose and two xyloglucans as ligands; the results suggest that the FaEG1-cellulose and FaEG1-XXXGXXXG (the most abundant xyloglucan in strawberries) complexes were more stable complexes than XXFGXXFG. The cell wall degradation was observed by scanning electron microscopy (SEM). The data are congruent with the probable role of the FaEG1 protein in the dissembly of the cellulose-hemicellulose fraction during the ripening of strawberry fruit.
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Cai LN, Xu SN, Lu T, Lin DQ, Yao SJ. Directed expression of halophilic and acidophilic β-glucosidases by introducing homologous constitutive expression cassettes in marine Aspergillus niger. J Biotechnol 2019; 292:12-22. [DOI: 10.1016/j.jbiotec.2018.12.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 12/18/2018] [Accepted: 12/29/2018] [Indexed: 01/31/2023]
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Kao MR, Kuo HW, Lee CC, Huang KY, Huang TY, Li CW, Chen CW, Wang AHJ, Yu SM, Ho THD. Chaetomella raphigera β-glucosidase D2-BGL has intriguing structural features and a high substrate affinity that renders it an efficient cellulase supplement for lignocellulosic biomass hydrolysis. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:258. [PMID: 31700541 PMCID: PMC6825360 DOI: 10.1186/s13068-019-1599-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/22/2019] [Indexed: 05/17/2023]
Abstract
BACKGROUND To produce second-generation biofuels, enzymatic catalysis is required to convert cellulose from lignocellulosic biomass into fermentable sugars. β-Glucosidases finalize the process by hydrolyzing cellobiose into glucose, so the efficiency of cellulose hydrolysis largely depends on the quantity and quality of these enzymes used during saccharification. Accordingly, to reduce biofuel production costs, new microbial strains are needed that can produce highly efficient enzymes on a large scale. RESULTS We heterologously expressed the fungal β-glucosidase D2-BGL from a Taiwanese indigenous fungus Chaetomella raphigera in Pichia pastoris for constitutive production by fermentation. Recombinant D2-BGL presented significantly higher substrate affinity than the commercial β-glucosidase Novozyme 188 (N188; K m = 0.2 vs 2.14 mM for p-nitrophenyl β-d-glucopyranoside and 0.96 vs 2.38 mM for cellobiose). When combined with RUT-C30 cellulases, it hydrolyzed acid-pretreated lignocellulosic biomasses more efficiently than the commercial cellulase mixture CTec3. The extent of conversion from cellulose to glucose was 83% for sugarcane bagasse and 63% for rice straws. Compared to N188, use of D2-BGL halved the time necessary to produce maximal levels of ethanol by a semi-simultaneous saccharification and fermentation process. We upscaled production of recombinant D2-BGL to 33.6 U/mL within 15 days using a 1-ton bioreactor. Crystal structure analysis revealed that D2-BGL belongs to glycoside hydrolase (GH) family 3. Removing the N-glycosylation N68 or O-glycosylation T431 residues by site-directed mutagenesis negatively affected enzyme production in P. pastoris. The F256 substrate-binding residue in D2-BGL is located in a shorter loop surrounding the active site pocket relative to that of Aspergillus β-glucosidases, and this short loop is responsible for its high substrate affinity toward cellobiose. CONCLUSIONS D2-BGL is an efficient supplement for lignocellulosic biomass saccharification, and we upscaled production of this enzyme using a 1-ton bioreactor. Enzyme production could be further improved using optimized fermentation, which could reduce biofuel production costs. Our structure analysis of D2-BGL offers new insights into GH3 β-glucosidases, which will be useful for strain improvements via a structure-based mutagenesis approach.
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Affiliation(s)
- Mu-Rong Kao
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and National Defense Medical Center, Taipei, Taiwan, ROC
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Hsion-Wen Kuo
- Department of Environmental Science and Engineering, Tunghai University, Taichung, Taiwan, ROC
| | - Cheng-Chung Lee
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, ROC
| | - Kuan-Ying Huang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Ting-Yen Huang
- Department of Bioengineering, Tatung University, Taipei, Taiwan, ROC
| | - Chen-Wei Li
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - C. Will Chen
- Department of Bioengineering, Tatung University, Taipei, Taiwan, ROC
| | | | - Su-May Yu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Tuan-Hua David Ho
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
- Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
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Salgado JCS, Meleiro LP, Carli S, Ward RJ. Glucose tolerant and glucose stimulated β-glucosidases - A review. BIORESOURCE TECHNOLOGY 2018; 267:704-713. [PMID: 30093225 DOI: 10.1016/j.biortech.2018.07.137] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 07/24/2018] [Accepted: 07/26/2018] [Indexed: 05/22/2023]
Abstract
The β-glucosidases (β-D-glucoside glucohydrolase, EC 3.2.1.21) hydrolyze glycosidic bonds of alkyl-, amino-, or aryl-β-D-glucosides, cyanogenic glucosides, disaccharides and short oligosaccharides and can also catalyze the synthesis of glycosyl-bonds between different molecules via transglycosylation. Due to their ubiquitous phylogenetic distribution, substrate diversity and ability to both hydrolyze and synthesize glycosidic bonds, the catalysis and regulation of β-glucosidases have been extensively studied. Many β-glucosidases are inhibited by the reaction product glucose, and reduced catalytic activity may limit the biotechnological and industrial applications of these enzymes and this has stimulated the search for β-glucosidases that maintain their activity at high glucose concentrations. Studies of many glucose tolerant enzymes have been reported and due to the ongoing interest in these enzymes, here it has been reviewed this accumulated body of knowledge which provides valuable insights as to the kinetics, structure, regulation and evolution of glucose tolerant and glucose stimulated β-glucosidases.
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Affiliation(s)
- José Carlos Santos Salgado
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Luana Parras Meleiro
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil.
| | - Sibeli Carli
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Richard John Ward
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
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Nargotra P, Sharma V, Gupta M, Kour S, Bajaj BK. Application of ionic liquid and alkali pretreatment for enhancing saccharification of sunflower stalk biomass for potential biofuel-ethanol production. BIORESOURCE TECHNOLOGY 2018; 267:560-568. [PMID: 30053714 DOI: 10.1016/j.biortech.2018.07.070] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 07/12/2018] [Accepted: 07/13/2018] [Indexed: 06/08/2023]
Abstract
Biorefining of lignocellulosic biomass to fuels/chemicals has recently gained immense research momentum. Current study reports sequential pretreatment of sunflower stalk (SFS) biomass in a combinatorial regime involving alkali (NaOH) and ionic liquid 1-butyl-3-methyl imidazolium chloride. The pretreatment enhanced the enzymatic digestibility, and resulted in increased sugar yield (163.42 mg/g biomass) as compared to standalone pretreatment using alkali (97.38 mg/g biomass) or ionic liquid (79.6 mg/g biomass). Ultrastructural and morphological analysis (FTIR and SEM) of pretreated biomass showed that the combined ionic liquid and alkali pretreatment causes more drastic alterations in the biomass ultrastructure as compared to alone ionic liquid or alkali pretreatment. Thus, combined pretreatment led to ease of enzymatic saccharification and consequent increased sugar yield, and this observation was corroborated by physicochemical analysis of the pretreated biomass. The pretreated SFS biomass was subjected to consolidated bioprocessing for its direct conversion to bioethanol in a single vessel.
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Affiliation(s)
- Parushi Nargotra
- School of Biotechnology, University of Jammu, Jammu 180006, India
| | - Vishal Sharma
- School of Biotechnology, University of Jammu, Jammu 180006, India
| | - Mahak Gupta
- School of Biotechnology, University of Jammu, Jammu 180006, India
| | - Simranjeet Kour
- School of Biotechnology, University of Jammu, Jammu 180006, India
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Functional characterization of GH7 endo-1,4-β-glucanase from Aspergillus fumigatus and its potential industrial application. Protein Expr Purif 2018; 150:1-11. [DOI: 10.1016/j.pep.2018.04.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 04/24/2018] [Accepted: 04/24/2018] [Indexed: 11/23/2022]
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Molecular Characterization and Potential Synthetic Applications of GH1 β-Glucosidase from Higher Termite Microcerotermes annandalei. Appl Biochem Biotechnol 2018; 186:877-894. [PMID: 29779183 DOI: 10.1007/s12010-018-2781-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 05/08/2018] [Indexed: 10/16/2022]
Abstract
A novel β-glucosidase from higher termite Microcerotermes annandalei (MaBG) was obtained via a screening method targeting β-glucosidases with increased activities in the presence of glucose. The purified natural MaBG showed a subunit molecular weight of 55 kDa and existed in a native form as a dimer without any glycosylation. Gene-specific primers designed from its partial amino acid sequences were used to amplify the corresponding 1,419-bp coding sequence of MaBG which encodes a 472-amino acid glycoside hydrolase family 1 (GH1) β-glucosidase. When expressed in Komagataella pastoris, the recombinant MaBG appeared as a ~ 55-kDa protein without glycosylation modifications. Kinetic parameters as well as the lack of secretion signal suggested that MaBG is an intracellular enzyme and not involved in cellulolysis. The hydrolytic activities of MaBG were enhanced in the presence of up to 3.5-4.5 M glucose, partly due to its strong transglucosylation activity, which suggests its applicability in biosynthetic processes. The potential synthetic activities of the recombinant MaBG were demonstrated in the synthesis of para-nitrophenyl-β-D-gentiobioside via transglucosylation and octyl glucoside via reverse hydrolysis. The information obtained from this study has broadened our insight into the functional characteristics of this variant of termite GH1 β-glucosidase and its applications in bioconversion and biotechnology.
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Méndez-Líter JA, de Eugenio LI, Prieto A, Martínez MJ. The β-glucosidase secreted by Talaromyces amestolkiae under carbon starvation: a versatile catalyst for biofuel production from plant and algal biomass. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:123. [PMID: 29719566 PMCID: PMC5921417 DOI: 10.1186/s13068-018-1125-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 04/20/2018] [Indexed: 05/17/2023]
Abstract
BACKGROUND In the last years, the most outstanding trend for obtaining high added-value components and second-generation (2G) biofuels consisted on exploitation of plant biomass. But recently, 3G biofuels, based in algae biomass, have emerged as a great alternative for production of energy. RESULTS In this work, a versatile β-glucosidase from the ascomycete fungus Talaromyces amestolkiae has been purified, characterized, and heterologously expressed. The synthesis of this β-glucosidase (BGL-3) was not induced by cellulose, and the presence of a specific carbon source is not required for its production, which is uncommon for β-glucosidases. BGL-3, which was obtained from a basal medium with glucose as carbon source, was profusely secreted under carbon starvation conditions, which was corroborated by qRT-PCR assays. BGL-3 was purified from T. amestolkiae cultures in one step, and biochemically characterized. The enzyme showed high thermal stability, and very high efficiency on pNPG (Km of 0.14 mM and Vmax of 381.1 U/mg), cellobiose (Km of 0.48 mM and Vmax of 447.1 U/mg), and other cello-oligosaccharides. Surprisingly, it also showed remarkable ability to hydrolyze laminarin, a β-1,3-glucan present in algae. The recombinant enzyme, obtained in the yeast Pichia pastoris, exhibited kinetic and physicochemical properties similar to those found for the native protein. Enzyme efficiency was examined in wheat straw saccharification processes, in which BGL-3 worked better supplementing Celluclast 1.5L than the commercial cellulase cocktail N-50010. Besides, BGL-3 hydrolyzed laminarin more efficiently than a commercial laminarinase. CONCLUSIONS A very efficient 1,4-β-glucosidase, which also showed activity over 1,3-β-glucose bonds, has been produced, purified, and characterized. This is the first report of such versatility in a 1,4-β-glucosidase. The application of this enzyme for saccharification of wheat straw and laminarin and its comparison with commercial enzymes suggest that it could be an interesting tool for the production of 2G and 3G biofuels.
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Affiliation(s)
- Juan Antonio Méndez-Líter
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Laura Isabel de Eugenio
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Alicia Prieto
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - María Jesús Martínez
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
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Construction of a cellulose-metabolizing Komagataella phaffii (Pichia pastoris) by co-expressing glucanases and β-glucosidase. Appl Microbiol Biotechnol 2017; 102:1297-1306. [DOI: 10.1007/s00253-017-8656-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/12/2017] [Accepted: 11/14/2017] [Indexed: 12/22/2022]
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Kar B, Verma P, den Haan R, Sharma AK. Characterization of a recombinant thermostable β-glucosidase from Putranjiva roxburghii expressed in Saccharomyces cerevisiae and its use for efficient biomass conversion. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Singhania RR, Patel AK, Pandey A, Ganansounou E. Genetic modification: A tool for enhancing beta-glucosidase production for biofuel application. BIORESOURCE TECHNOLOGY 2017; 245:1352-1361. [PMID: 28596076 DOI: 10.1016/j.biortech.2017.05.126] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/17/2017] [Accepted: 05/19/2017] [Indexed: 05/25/2023]
Abstract
Beta-glucosidase (BGL) is a rate-limiting enzyme for cellulose hydrolysis as it acts in the final step of lignocellulosic biomass conversion to convert cellobiose into glucose, the final end product. Most of the fungal strains used for cellulase production are deficient in BGL hence BGL is supplemented into cellulases to have an efficient biomass conversion. Genetic engineering has enabled strain modification to produce BGL optimally with desired properties to be employed for biofuel applications. It has been cloned either directly into the host strains lacking BGL or into another expression system, to be overexpressed so as to be blended into BGL deficient cellulases. In this article, role of genetic engineering to overcome BGL limitations in the cellulase cocktail and its significance for biofuel applications has been critically reviewed.
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Affiliation(s)
- Reeta Rani Singhania
- DBT-IOC Advanced Bio-Energy Research Centre, Indian Oil Corporation; R&D Centre, Sector-13, Faridabad 121007, India
| | - Anil Kumar Patel
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu 96822, HI, United States.
| | - Ashok Pandey
- Center of Innovative and Applied Bioprocessing, Sector 81, Knowledge City PO Manauli, SAS Nagar, Mohali 140306, Punjab, India
| | - Edgard Ganansounou
- Bioenergy and Energy Planning Research Group, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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Improved thermostability of a metagenomic glucose-tolerant β-glycosidase based on its X-ray crystal structure. Appl Microbiol Biotechnol 2017; 101:8353-8363. [DOI: 10.1007/s00253-017-8525-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 08/08/2017] [Accepted: 09/07/2017] [Indexed: 12/29/2022]
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Heterologous expression and biochemical studies of a thermostable glucose tolerant β-glucosidase from Methylococcus capsulatus ( bath strain ). Int J Biol Macromol 2017; 102:805-812. [DOI: 10.1016/j.ijbiomac.2017.04.078] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 12/18/2022]
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Kuusk S, Väljamäe P. When substrate inhibits and inhibitor activates: implications of β-glucosidases. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:7. [PMID: 28053666 PMCID: PMC5209912 DOI: 10.1186/s13068-016-0690-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/16/2016] [Indexed: 05/15/2023]
Abstract
BACKGROUND β-glucosidases (BGs) catalyze the hydrolysis of β-glycosidic bonds in glucose derivatives. They constitute an important group of enzymes with biotechnological interest like supporting cellulases in degradation of lignocellulose to fermentable sugars. In the latter context, the glucose tolerant BGs are of particular interest. These BGs often show peculiar kinetics, including inhibitory effects of substrates and activating effects of inhibitors, such as glucose or xylose. The mechanisms behind the activating/inhibiting effects are poorly understood. The nonproductive binding of substrate is expected in cases where enzymes with multiple consecutive binding subsites are studied on substrates with a low degree of polymerization. The effects of inhibitors to BGs exerting nonproductive binding of substrate have not been discussed in the literature before. RESULTS Here, we performed analyses of different reaction schemes using the catalysis by retaining BGs as a model. We found that simple competition of inhibitor with nonproductive binding of substrate can account for the activation of enzyme by inhibitor without involving any allosteric effects. The transglycosylation to inhibitor was also able to explain the activating effect of inhibitor. For both mechanisms, the activation was caused by the increase of kcat with increasing inhibitor concentration, while kcat/Km always decreased. Therefore, the activation by inhibitor was more pronounced at high substrate concentrations. The possible contribution of the two mechanisms in the activation by inhibitor was dependent on the rate-limiting step of glycosidic bond hydrolysis as well as on whether and which glucose-unit-binding subsites are interacting. CONCLUSION Knowledge on the mechanisms of the activating/inhibiting effects of inhibitors helps the rational engineering and selection of BGs for biotechnological applications. Provided that the catalysis is consistent with the reaction schemes addressed here and underlying assumptions, the mechanism of activation by inhibitor reported here is applicable for all enzymes exerting nonproductive binding of substrate.
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Affiliation(s)
- Silja Kuusk
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23b – 202, 51010 Tartu, Estonia
| | - Priit Väljamäe
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23b – 202, 51010 Tartu, Estonia
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Méndez-Líter JA, Gil-Muñoz J, Nieto-Domínguez M, Barriuso J, de Eugenio LI, Martínez MJ. A novel, highly efficient β-glucosidase with a cellulose-binding domain: characterization and properties of native and recombinant proteins. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:256. [PMID: 29142591 PMCID: PMC5674860 DOI: 10.1186/s13068-017-0946-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/26/2017] [Indexed: 05/07/2023]
Abstract
BACKGROUND Cellulose, the most abundant biopolymer on earth, is an alternative for fossil fuels as a renewable feedstock for the production of second-generation biofuels and other chemicals. The discovery of novel, highly efficient β-glucosidases remains as one of the major bottlenecks for cellulose degradation. In this context, the ascomycete Talaromyces amestolkiae, isolated from cereal samples, has been studied as a promising source for these enzymes. RESULTS BGL-2 is the major β-glucosidase secreted by this fungus in the presence of cellulosic inductors. This enzyme possesses a CBD (Cellulose Binding Domain), an unusual feature among this type of proteins. Besides, when growing on cellulose, the fungus produced two different bgl-2 mRNAs that were cloned and expressed in Pichia pastoris. A complete recombinant protein (BGL-2*) and its truncated form, lacking CBD (BGL-2T*), have been purified, characterized and compared with the native enzyme (BGL-2). The three BGL-2 forms studied are highly stable in a wide pH range, but BGL-2T* showed an improved thermal stability at 50 °C after 72 h. Using p-nitrophenyl-β-d-glucopyranoside as a substrate, the steady-state kinetic characterization of the three proteins showed a similar Km and kcat for BGL-2 and BGL-2*, while the truncated protein displayed a threefold higher value for kcat . All tested BGL-2 enzymes were as well highly efficient using cellobiose and other short oligosaccharides as a substrate. In view of biotechnological applications, the recombinant T. amestolkiae enzymes in saccharification of brewers' spent grain were studied, being comparable to commercial β-glucosidase cocktails. CONCLUSION A new β-glucosidase from T. amestolkiae has been studied. The enzyme, containing a functional CBD, has been expressed in P. pastoris. The comparative analyses of the native protein and its recombinant forms, with and without CBD, suggest that they could be suitable tools for valorization of lignocellulosic biomass.
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Affiliation(s)
- J. A. Méndez-Líter
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - J. Gil-Muñoz
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - M. Nieto-Domínguez
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - J. Barriuso
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - L. I. de Eugenio
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - M. J. Martínez
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
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Purification, characterization and gene analysis of a new α-glucosidase from shiraia sp. SUPER-H168. ANN MICROBIOL 2016. [DOI: 10.1007/s13213-016-1238-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Ergün BG, Çalık P. Lignocellulose degrading extremozymes produced by Pichia pastoris: current status and future prospects. Bioprocess Biosyst Eng 2016; 39:1-36. [PMID: 26497303 DOI: 10.1007/s00449-015-1476-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 09/21/2015] [Indexed: 02/06/2023]
Abstract
In this review article, extremophilic lignocellulosic enzymes with special interest on xylanases, β-mannanases, laccases and finally cellulases, namely, endoglucanases, exoglucanases and β-glucosidases produced by Pichia pastoris are reviewed for the first time. Recombinant lignocellulosic extremozymes are discussed from the perspectives of their potential application areas; characteristics of recombinant and native enzymes; the effects of P. pastoris expression system on recombinant extremozymes; and their expression levels and applied strategies to increase the enzyme expression yield. Further, effects of enzyme domains on activity and stability, protein engineering via molecular dynamics simulation and computational prediction, and site-directed mutagenesis and amino acid modifications done are also focused. Superior enzyme characteristics and improved stability due to the proper post-translational modifications and better protein folding performed by P. pastoris make this host favourable for extremozyme production. Especially, glycosylation contributes to the structure, function and stability of enzymes, as generally glycosylated enzymes produced by P. pastoris exhibit better thermostability than non-glycosylated enzymes. However, there has been limited study on enzyme engineering to improve catalytic efficiency and stability of lignocellulosic enzymes. Thus, in the future, studies should focus on protein engineering to improve stability and catalytic efficiency via computational modelling, mutations, domain replacements and fusion enzyme technology. Also metagenomic data need to be used more extensively to produce novel enzymes with extreme characteristics and stability.
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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]
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Secretory expression, characterization and docking study of glucose-tolerant β-glucosidase from B. subtilis. Int J Biol Macromol 2016; 85:425-33. [DOI: 10.1016/j.ijbiomac.2016.01.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 12/27/2015] [Accepted: 01/01/2016] [Indexed: 01/19/2023]
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Guo B, Amano Y, Nozaki K. Improvements in Glucose Sensitivity and Stability of Trichoderma reesei β-Glucosidase Using Site-Directed Mutagenesis. PLoS One 2016; 11:e0147301. [PMID: 26790148 PMCID: PMC4720395 DOI: 10.1371/journal.pone.0147301] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 01/02/2016] [Indexed: 01/07/2023] Open
Abstract
Glucose sensitivity and pH and thermal stabilities of Trichoderma reesei Cel1A (Bgl II) were improved by site-directed mutagenesis of only two amino acid residues (L167W or P172L) at the entrance of the active site. The Cel1A mutant showed high glucose tolerance (50% of inhibitory concentration = 650 mM), glucose stimulation (2.0 fold at 50 mM glucose), and enhanced specific activity (2.4-fold) compared with those of the wild-type Cel1A. Furthermore, the mutant enzyme showed stability at a wide pH range of 4.5–9.0 and possessed high thermal stability up to 50°C with 80% of the residual activities compared with the stability seen at the pH range of 6.5–7.0 and temperatures of up to 40°C in the wild-type Cel1A. Kinetic studies for hydrolysis revealed that the Cel1A mutant was competitively inhibited by glucose at similar levels as the wild-type enzyme. Additionally, the mutant enzyme exhibited substrate inhibition, which gradually disappeared with an increasing glucose concentration. These data suggest that the glucose stimulation was caused by relieve the substrate inhibition in the presence of glucose. To conclude, all the properties improved by the mutagenesis would be great advantages in degradation of cellulosic biomass together with cellulases.
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Affiliation(s)
- Boyang Guo
- Department of Bioscience and Textile Technology, Interdisciplinary Graduate School of Science and Technology, Shinshu University, Nagano, Japan
| | - Yoshihiko Amano
- Department of Bioscience and Textile Technology, Interdisciplinary Graduate School of Science and Technology, Shinshu University, Nagano, Japan
| | - Kouichi Nozaki
- Department of Bioscience and Textile Technology, Interdisciplinary Graduate School of Science and Technology, Shinshu University, Nagano, Japan
- * E-mail:
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de Amorim Araújo J, Ferreira TC, Rubini MR, Duran AGG, De Marco JL, de Moraes LMP, Torres FAG. Coexpression of cellulases in Pichia pastoris as a self-processing protein fusion. AMB Express 2015; 5:84. [PMID: 26698316 PMCID: PMC4689727 DOI: 10.1186/s13568-015-0170-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 12/11/2015] [Indexed: 02/06/2023] Open
Abstract
The term cellulase refers to any component of the enzymatic complex produced by some fungi, bacteria and protozoans which act serially or synergistically to catalyze the cleavage of cellulosic materials. Cellulases have been widely used in many industrial applications ranging from food industry to the production of second generation ethanol. In an effort to develop new strategies to minimize the costs of enzyme production we describe the development of a Pichia pastoris strain able to coproduce two different cellulases. For that purpose the eglII (endoglucanase II) and cbhII (cellobiohydrolase II) genes from Trichoderma reesei were fused in-frame separated by the self-processing 2A peptide sequence from the foot-and-mouth disease virus. The protein fusion construct was placed under the control of the strong inducible AOX1 promoter. Analysis of culture supernatants from methanol-induced yeast transformants showed that the protein fusion was effectively processed. Enzymatic assay showed that the processed enzymes were fully functional with the same catalytic properties of the individual enzymes produced separately. Furthermore, when combined both enzymes acted synergistically on filter paper to produce cellobiose as the main end-product. Based on these results we propose that P. pastoris should be considered as an alternative platform for the production of cellulases at competitive costs.
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Ramani G, Meera B, Rajendhran J, Gunasekaran P. Transglycosylating glycoside hydrolase family 1 β-glucosidase from Penicillium funiculosum NCL1: Heterologous expression in Escherichia coli and characterization. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2015.03.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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37
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Expression of novel glucose tolerant β-glucosidase on cell surface by Rhodotorula glutinis isolate. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2015. [DOI: 10.1016/j.bcab.2015.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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