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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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Xie Y, Yan X, Li C, Wang S, Jia L. Characterization and insight mechanism of an acid-adapted β-Glucosidase from Lactobacillus paracasei and its application in bioconversion of glycosides. Front Bioeng Biotechnol 2024; 12:1334695. [PMID: 38333082 PMCID: PMC10851751 DOI: 10.3389/fbioe.2024.1334695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 01/15/2024] [Indexed: 02/10/2024] Open
Abstract
Introduction: β-glucosidase is one class of pivotal glycosylhydrolase enzyme that can cleavage glucosidic bonds and transfer glycosyl group between the oxygen nucleophiles. Lactobacillus is the most abundant bacteria in the human gut. Identification and characterization of new β-glucosidases from Lactobacillus are meaningful for food or drug industry. Method: Herein, an acid-adapted β-glucosidase (LpBgla) was cloned and characterized from Lactobacillus paracasei. And the insight acid-adapted mechanism of LpBgla was investigated using molecular dynamics simulations. Results and Discussion: The recombinant LpBgla exhibited maximal activity at temperature of 30°C and pH 5.5, and the enzymatic activity was inhibited by Cu2+, Mn2+, Zn2+, Fe2+, Fe3+ and EDTA. The LpBgla showed a more stable structure, wider substrate-binding pocket and channel aisle, more hydrogen bonds and stronger molecular interaction with the substrate at pH 5.5 than pH 7.5. Five residues including Asp45, Leu60, Arg120, Lys153 and Arg164 might play a critical role in the acid-adapted mechanism of LpBgla. Moreover, LpBgla showed a broad substrate specificity and potential application in the bioconversion of glycosides, especially towards the arbutin. Our study greatly benefits for the development novel β-glucosidases from Lactobacillus, and for the biosynthesis of aglycones.
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Affiliation(s)
- Yufeng Xie
- College of Food Science and Engineering, Harbin University, Harbin, China
- College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Xinrui Yan
- College of Food Science and Engineering, Harbin University, Harbin, China
| | - Changzhuo Li
- College of Food Science and Engineering, Harbin University, Harbin, China
| | - Shumei Wang
- College of Food Science and Engineering, Harbin University, Harbin, China
| | - Longgang Jia
- College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
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Jing G, Wenjun G, Yi W, Kepan X, Wen L, Tingting H, Zhiqiang C. Enhancing Enzyme Activity and Thermostability of Bacillus amyloliquefaciens Chitosanase BaCsn46A Through Saturation Mutagenesis at Ser196. Curr Microbiol 2023; 80:180. [PMID: 37046080 DOI: 10.1007/s00284-023-03281-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 03/21/2023] [Indexed: 04/14/2023]
Abstract
Chitosanase plays an important role in chitooligosaccharides (COS) production. We found that the chitosanase (BaCsn46A) of Bacillus amyloliquefacien was a good candidate for chitosan hydrolysis of COS. In order to further improve the enzyme properties of BaCsn46A, the S196 located near the active center was found to be a critical site impacts on enzyme properties by sequence alignment analysis. Herein, saturation mutation was carried out to study role of 196 site on BaCsn46A catalytic function. Compared with WT, the specific enzyme activity of S196A increased by 118.79%, and the thermostability of S196A was much higher than WT. In addition, we found that the enzyme activity of S196P was 2.41% of that of WT, indicating that the type of amino acid in 196 site could significant affect the catalytic activity and thermostability of BaCsn46A. After molecular docking analysis we found that the increase in hydrogen bonds and decrease in unfavorable bonds interacting with the substrate were the main reason for the change of enzyme properties which is valuable for future studies on Bacillus species chitosanase.
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Affiliation(s)
- Guo Jing
- Laboratory of Applied Microbiology, School of Biological and Food Engineering, Changzhou University, Changzhou Jiangsu, 213164, China
- Advanced Catalysis and Green Manufacturing Collaborative Innovation Center and Laboratory of Applied Microbiology, School of Pharmaceutical, Changzhou University, Changzhou, 213164, Jiangsu, China
| | - Gao Wenjun
- Laboratory of Applied Microbiology, School of Biological and Food Engineering, Changzhou University, Changzhou Jiangsu, 213164, China
| | - Wang Yi
- Laboratory of Applied Microbiology, School of Biological and Food Engineering, Changzhou University, Changzhou Jiangsu, 213164, China
| | - Xu Kepan
- Laboratory of Applied Microbiology, School of Biological and Food Engineering, Changzhou University, Changzhou Jiangsu, 213164, China
| | - Luo Wen
- Laboratory of Applied Microbiology, School of Biological and Food Engineering, Changzhou University, Changzhou Jiangsu, 213164, China
| | - Hong Tingting
- Laboratory of Applied Microbiology, School of Biological and Food Engineering, Changzhou University, Changzhou Jiangsu, 213164, China
- Advanced Catalysis and Green Manufacturing Collaborative Innovation Center and Laboratory of Applied Microbiology, School of Pharmaceutical, Changzhou University, Changzhou, 213164, Jiangsu, China
| | - Cai Zhiqiang
- Laboratory of Applied Microbiology, School of Biological and Food Engineering, Changzhou University, Changzhou Jiangsu, 213164, China.
- Advanced Catalysis and Green Manufacturing Collaborative Innovation Center and Laboratory of Applied Microbiology, School of Pharmaceutical, Changzhou University, Changzhou, 213164, Jiangsu, China.
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Galf-containing polysaccharides from medicinal molds: Sources, structures and bioactive properties. Trends Food Sci Technol 2022. [DOI: 10.1016/j.tifs.2022.11.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Ajeje SB, Hu Y, Song G, Peter SB, Afful RG, Sun F, Asadollahi MA, Amiri H, Abdulkhani A, Sun H. Thermostable Cellulases / Xylanases From Thermophilic and Hyperthermophilic Microorganisms: Current Perspective. Front Bioeng Biotechnol 2021; 9:794304. [PMID: 34976981 PMCID: PMC8715034 DOI: 10.3389/fbioe.2021.794304] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 11/02/2021] [Indexed: 12/13/2022] Open
Abstract
The bioconversion of lignocellulose into monosaccharides is critical for ensuring the continual manufacturing of biofuels and value-added bioproducts. Enzymatic degradation, which has a high yield, low energy consumption, and enhanced selectivity, could be the most efficient and environmentally friendly technique for converting complex lignocellulose polymers to fermentable monosaccharides, and it is expected to make cellulases and xylanases the most demanded industrial enzymes. The widespread nature of thermophilic microorganisms allows them to proliferate on a variety of substrates and release substantial quantities of cellulases and xylanases, which makes them a great source of thermostable enzymes. The most significant breakthrough of lignocellulolytic enzymes lies in lignocellulose-deconstruction by enzymatic depolymerization of holocellulose into simple monosaccharides. However, commercially valuable thermostable cellulases and xylanases are challenging to produce in high enough quantities. Thus, the present review aims at giving an overview of the most recent thermostable cellulases and xylanases isolated from thermophilic and hyperthermophilic microbes. The emphasis is on recent advancements in manufacturing these enzymes in other mesophilic host and enhancement of catalytic activity as well as thermostability of thermophilic cellulases and xylanases, using genetic engineering as a promising and efficient technology for its economic production. Additionally, the biotechnological applications of thermostable cellulases and xylanases of thermophiles were also discussed.
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Affiliation(s)
- Samaila Boyi Ajeje
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Yun Hu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Guojie Song
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Sunday Bulus Peter
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Richmond Godwin Afful
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Fubao Sun
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Mohammad Ali Asadollahi
- Department of Biotechnology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran
| | - Hamid Amiri
- Department of Biotechnology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran
| | - Ali Abdulkhani
- Department of Wood and Paper Science and Technology, Faculty of Natural Resources, University of Tehran, Karaj, Iran
| | - Haiyan Sun
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
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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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Luo S, Qin Z, Chen Q, Fan L, Jiang L, Zhao L. High level production of a Bacillus amlyoliquefaciens chitosanase in Pichia pastoris suitable for chitooligosaccharides preparation. Int J Biol Macromol 2020; 149:1034-1041. [PMID: 32027900 DOI: 10.1016/j.ijbiomac.2020.02.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/01/2020] [Accepted: 02/01/2020] [Indexed: 02/06/2023]
Abstract
Chitooligosaccharides (COS) are hydrolytic products of chitosan that are essential in functional food, medicine, and other fields due to their biological activities. Commercial COS are often prepared by the hydrolysis of chitosan by chitosanase. In this study, a glycoside hydrolase family 46 cluster B chitosanase from Bacillus amyloliquefaciens (BaCsn46B) was efficiently expressed in Pichia pastoris. The recombinant enzyme was secreted into the culture medium that reached a total extracellular protein concentration of 4.5 g/L with an activity of 8907.2 U/mL in a high cell density fermenter (5 L). The molecular mass of deglycosylated BaCsn46B was 29.0 kDa. Purified BaCsn46B exhibited excellent enzymatic properties, which had high specific activity (2380.5 U/mg) under optimal reaction conditions (55 °C and pH 6.5). BaCsn46B hydrolyzed chitosan yielded a series of COS with different degrees of polymerization by endo-type cleavage. The end hydrolytic products of BaCsn46B were chitobiose and chitotriose, while no monosaccharide yield was evident in the hydrolytic reaction. The excellent secreted expression level and hydrolytic performance make the enzyme a desirable biocatalyst for the industrial preparation of COS.
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Affiliation(s)
- Sa Luo
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, R&D Center of Separation and Extraction Technology in Fermentation Industry, East China University of Science and Technology, Shanghai 200237, China
| | - Zhen Qin
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, R&D Center of Separation and Extraction Technology in Fermentation Industry, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai 200237, China.
| | - Qiming Chen
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, R&D Center of Separation and Extraction Technology in Fermentation Industry, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai 200237, China
| | - Liqiang Fan
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, R&D Center of Separation and Extraction Technology in Fermentation Industry, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai 200237, China
| | - Lihua Jiang
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, R&D Center of Separation and Extraction Technology in Fermentation Industry, East China University of Science and Technology, Shanghai 200237, China
| | - Liming Zhao
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, R&D Center of Separation and Extraction Technology in Fermentation Industry, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai 200237, China.
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8
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Ballmann P, Lightfoot J, Müller M, Dröge S, Prade R. Redesigning the Aspergillus nidulans xylanase regulatory pathway to enhance cellulase production with xylose as the carbon and inducer source. Microb Cell Fact 2019; 18:193. [PMID: 31699093 PMCID: PMC6839167 DOI: 10.1186/s12934-019-1243-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 10/24/2019] [Indexed: 11/10/2022] Open
Abstract
Background Biomass contains cellulose (C6-sugars), hemicellulose (C5-sugars) and lignin. Biomass ranks amongst the most abundant hydrocarbon resources on earth. However, biomass is recalcitrant to enzymatic digestion by cellulases. Physicochemical pretreatment methods make cellulose accessible but partially destroy hemicellulose, producing a C5-sugar-rich liquor. Typically, digestion of pretreated LCB is performed with commercial cellulase preparations, but C5-sugars could in principle be used for “on site” production of cellulases by genetically engineered microorganism, thereby reducing costs. Results Here we report a succession of genetic interventions in Aspergillus nidulans that redesign the natural regulatory circuitry of cellulase genes in such a way that recombinant strains use C5-sugar liquors (xylose) to grow a vegetative tissue and simultaneously accumulate large amounts of cellulases. Overexpression of XlnR showed that under xylose-induction conditions only xylanase C was produced. XlnR overexpression strains were constructed that use the xynCp promoter to drive the production of cellobiohydrolases, endoglucanases and β-glucosidase. All five cellulases accumulated at high levels when grown on xylose. Production of cellulases in the presence of pretreated-biomass C5-sugar liquors was investigated, and cellulases accumulated to much higher enzyme titers than those obtained for traditional fungal cell factories with cellulase-inducing substrates. Conclusions By replacing expensive substrates with a cheap by-product carbon source, the use of C5-sugar liquors directly derived from LCB pretreatment processes not only reduces enzyme production costs, but also lowers operational costs by eliminating the need for off-site enzyme production, purification, concentration, transport and dilution.
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Affiliation(s)
- Patrick Ballmann
- Prüf- und Forschungsinstitut Pirmasens e.V., Marie-Curie-Strasse 19, 66953, Pirmasens, Germany
| | - Jorge Lightfoot
- Department of Microbiology & Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Michael Müller
- Prüf- und Forschungsinstitut Pirmasens e.V., Marie-Curie-Strasse 19, 66953, Pirmasens, Germany
| | - Stephan Dröge
- Prüf- und Forschungsinstitut Pirmasens e.V., Marie-Curie-Strasse 19, 66953, Pirmasens, Germany
| | - Rolf Prade
- Department of Microbiology & Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA.
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Chen Z, Liu Y, Liu L, Chen Y, Li S, Jia Y. Purification and characterization of a novel β-glucosidase from Aspergillus flavus and its application in saccharification of soybean meal. Prep Biochem Biotechnol 2019; 49:671-678. [PMID: 30990111 DOI: 10.1080/10826068.2019.1599397] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Aspergillus flavus has been regarded as a potential candidate for its production of industrial enzymes, but the details of β-glucosidase from this strain is very limited. In herein, we first reported a novel β-glucosidase (AfBglA) with the molecular mass of 94.2 kDa from A. flavus. AfBglA was optimally active at pH 4.5 and 60 °C and is stable between pH 3.5 and 9.0 and at a temperature of up to 55 °C for 30 min remaining more than 90% of its initial activity. It showed an excellent tolerance to Trypsin, Pepsin, Compound Protease, and Flavourzyme and its activity was not inhibited by specific certain cations. AfBglA displayed broad substrate specificity, it acted on all tested pNP-glycosides and barley glucan, indicating this novel β-glucosidase exhibited a β-1, 3-1, 4-glucanase activity. Moreover, the AfBglA could effectively hydrolyze the soybean meal suspension into glucose and exhibit a strong tolerance to the inhibition of glucose at a concentration of 20.0 g/L during the saccharification. The maximum amount of the glucose obtained by AfBglA corresponded to 67.0 g/kg soybean meal. All of these properties mentioned above indicated that the AfBglA possibly attractive for food and feed industry and saccharification of cellulolytic materials.
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Affiliation(s)
- Zhou Chen
- a Lab of Enzyme Engineering, School of Food and Chemical Engineering , Beijing Technology and Business University , Beijing , China
| | - Yangliu Liu
- a Lab of Enzyme Engineering, School of Food and Chemical Engineering , Beijing Technology and Business University , Beijing , China
| | - Lu Liu
- a Lab of Enzyme Engineering, School of Food and Chemical Engineering , Beijing Technology and Business University , Beijing , China
| | - Yaoyao Chen
- a Lab of Enzyme Engineering, School of Food and Chemical Engineering , Beijing Technology and Business University , Beijing , China
| | - Siting Li
- a Lab of Enzyme Engineering, School of Food and Chemical Engineering , Beijing Technology and Business University , Beijing , China
| | - Yingmin Jia
- a Lab of Enzyme Engineering, School of Food and Chemical Engineering , Beijing Technology and Business University , Beijing , China
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Escuder-Rodríguez JJ, DeCastro ME, Cerdán ME, Rodríguez-Belmonte E, Becerra M, González-Siso MI. Cellulases from Thermophiles Found by Metagenomics. Microorganisms 2018; 6:microorganisms6030066. [PMID: 29996513 PMCID: PMC6165527 DOI: 10.3390/microorganisms6030066] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 07/04/2018] [Accepted: 07/05/2018] [Indexed: 01/05/2023] Open
Abstract
Cellulases are a heterogeneous group of enzymes that synergistically catalyze the hydrolysis of cellulose, the major component of plant biomass. Such reaction has biotechnological applications in a broad spectrum of industries, where they can provide a more sustainable model of production. As a prerequisite for their implementation, these enzymes need to be able to operate in the conditions the industrial process requires. Thus, cellulases retrieved from extremophiles, and more specifically those of thermophiles, are likely to be more appropriate for industrial needs in which high temperatures are involved. Metagenomics, the study of genes and gene products from the whole community genomic DNA present in an environmental sample, is a powerful tool for bioprospecting in search of novel enzymes. In this review, we describe the cellulolytic systems, we summarize their biotechnological applications, and we discuss the strategies adopted in the field of metagenomics for the discovery of new cellulases, focusing on those of thermophilic microorganisms.
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Affiliation(s)
- Juan-José Escuder-Rodríguez
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - María-Eugenia DeCastro
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - María-Esperanza Cerdán
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - Esther Rodríguez-Belmonte
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - Manuel Becerra
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
| | - María-Isabel González-Siso
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía, Facultade de Ciencias, Universidade da Coruña, 15071 A Corunna, Spain.
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11
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Xia Y, Yang L, Xia L. High-level production of a fungal β-glucosidase with application potentials in the cost-effective production of Trichoderma reesei cellulase. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.03.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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12
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Sarsaiya S, Awasthi SK, Awasthi MK, Awasthi AK, Mishra S, Chen J. The dynamic of cellulase activity of fungi inhabiting organic municipal solid waste. BIORESOURCE TECHNOLOGY 2018; 251:411-415. [PMID: 29268952 DOI: 10.1016/j.biortech.2017.12.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/03/2017] [Accepted: 12/06/2017] [Indexed: 06/07/2023]
Abstract
The study dealt with to identified and screened out potential cellulase producing fungal strains. All the indigenous fungal strains were developed on carboxymethyl cellulose (CMC) mandel media at 30 °C for 3-4 days to examine their congo red cellulase activity. It was found from the primary screening test result that only four isolates Trichoderma viride, Aspergillus niger, Aspergillus fumigatus and Fusarium oxysporum were shown large zone formation that meant they have great potential cellulase activity. Among these, Trichoderma viride and Aspergillus niger strains were showed highest enzymatic activity during the secondary screening, while Trichoderma viride generated the highest protein (89.51 μg/ml). Furthermore, these potential fungal strains will be useful for the organic municipal solid waste degradation.
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Affiliation(s)
- Surendra Sarsaiya
- Key Laboratory of Basic Pharmacology and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China; Sri Satya Sai University of Technology and Medical Sciences, Sehore, Madhya Pradesh, India
| | - Sanjeev Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, China
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, China; Department of Biotechnology, Amicable Knowledge Solution University, Satna, India.
| | - Abhishek Kumar Awasthi
- Department of Biological Sciences, Rani Durgawati University, Jabalpur, India; Present address: State Key Joint Laboratory of Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Saket Mishra
- Madhya Pradesh Pollution Control Board, Bhopal, Madhya Pradesh, India
| | - Jishuang Chen
- Key Laboratory of Basic Pharmacology and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China; Institute of Bioresources Engineering, Nanjing Tech University, Nanjing 211816, Jiangsu, China
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13
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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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14
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Heterologous Expression and Characterization of a GH3 β-Glucosidase from Thermophilic Fungi Myceliophthora thermophila in Pichia pastoris. Appl Biochem Biotechnol 2015; 177:511-27. [PMID: 26234435 DOI: 10.1007/s12010-015-1759-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Accepted: 07/14/2015] [Indexed: 01/06/2023]
Abstract
A novel β-glucosidase of glycoside hydrolase (GH) family 3 from Myceliophthora thermophila (mtbgl3b) was successfully expressed in Pichia pastoris. The full-length gene consists of 2613 bp nucleotides encoding a protein of 870 amino acids. MtBgl3b showed maximum activity at pH 5.0 and remained more than 70 % relative activity at 3.5-6.0. The enzyme displayed the highest activity at 60 °C and kept about 90 % relative activity for 50-65 °C; besides, the enzyme showed psychrophilic trait and remains 51 % relative activity at 40 °C. MtBgl3b exhibited good stability over a wide pH range of 3.0-10.0 and was thermostable at 60 and 65 °C. The enzyme displayed highest activity towards p-nitrophenyl-β-D-glucopyranoside (pNPG), followed by p-nitrophenyl-D-cellobioside (pNPC), cellotetraose, cellotriose, cellobiose, and gentiobiose. When using 10 % cellobiose (w/v) as the substrate, the enzyme showed transglycosylation activity to produce the cellotriose. The kinetic parametric of K m and V max were 2.78 mM and 927.9 μM mg(-1) min(-1), respectively. Finally, the reaction mode of the enzyme and the substrates were analyzed by molecular docking approach.
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15
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Hong SM, Sung HS, Kang MH, Kim CG, Lee YH, Kim DJ, Lee JM, Kusakabe T. Characterization of Cryptopygus antarcticus endo-β-1,4-glucanase from Bombyx mori expression systems. Mol Biotechnol 2015; 56:878-89. [PMID: 24848382 DOI: 10.1007/s12033-014-9767-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Endo-β-1,4-glucanase (CaCel) from Antarctic springtail, Cryptopygus antarcticus, a cellulase with high activity at low temperature, shows potential industrial use. To obtain sufficient active cellulase for characterization, CaCel gene was expressed in Bombyx mori-baculovirus expression systems. Recombinant CaCel (rCaCel) has been expressed in Escherichia coli (Ec-CaCel) at temperatures below 10°C, but the expression yield was low. Here, rCaCel with a silkworm secretion signal (Bm-CaCel) was successfully expressed and secreted into pupal hemolymph and purified to near 90% purity by Ni-affinity chromatography. The yield and specific activity of rCaCel purified from B. mori were estimated at 31 mg/l and 43.2 U/mg, respectively, which is significantly higher than the CaCel yield obtained from E. coli (0.46 mg/l and 35.8 U/mg). The optimal pH and temperature for the rCaCels purified from E. coli and B. mori were 3.5 and 50°C. Both rCaCels were active at a broad range of pH values and temperatures, and retained more than 30% of their maximal activity at 0°C. Oligosaccharide structural analysis revealed that Bm-CaCel contains elaborated N- and O-linked glycans, whereas Ec-CaCel contains putative O-linked glycans. Thermostability of Bm-CaCel from B. mori at 60°C was higher than that from E. coli, probably due to glycosylation.
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Affiliation(s)
- Sun Mee Hong
- Research and Development Department, Gyeongbuk Institute for Marine Bioindustry, Uljin, 767-813, Republic of Korea,
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16
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Xue YM, Xu CY, Hou JJ, Li XQ, Cao ZG. Enhanced soluble expression of a thermostble β-glucosidase from Thermotoga maritima in Escherichia coli and its applicaton in immobilization. APPL BIOCHEM MICRO+ 2015. [DOI: 10.1134/s0003683815030175] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Expression and characterization of a novel β-glucosidase, with transglycosylation and exo-β-1,3-glucanase activities, from Rhizomucor miehei. Food Chem 2014; 175:431-8. [PMID: 25577102 DOI: 10.1016/j.foodchem.2014.12.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 11/16/2014] [Accepted: 12/02/2014] [Indexed: 12/27/2022]
Abstract
A novel β-glucosidase gene, designated RmBglu3B, was cloned from the thermophilic fungus, Rhizomucor miehei CAU432. Its 2196-bp open reading frame encoded 731 amino acids. Its deduced amino-acid sequence showed highest identity (66%) with a glycoside hydrolase family 3 β-glucosidase from R. miehei NRRL5382. RmBglu3B was successfully expressed in Escherichia coli. The recombinant enzyme was purified to homogeneity with 18.2-fold purification and 59% recovery yield. Molecular masses of 76.5 kDa, by SDS-PAGE, and 66.4 kDa, by gel filtration, suggested that it is a monomer. Optimal pH and temperature of the purified enzyme were 5.0 and 50°C, respectively. RmBglu3B exhibited a broad range of substrate specificity, catalyzing the cleavage of β-1,2, β-1,3, β-1,4 and β-1,6 linkages, in various oligosaccharides, to liberate glucose. RmBglu3B also showed relatively high activity (19.1 U/mg) toward laminaran and transglycosylation activity, enabling gentiobiose production. This enzyme is a potential candidate for several industrial applications.
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Huang Y, Busk PK, Grell MN, Zhao H, Lange L. Identification of a β-glucosidase from the Mucor circinelloides genome by peptide pattern recognition. Enzyme Microb Technol 2014; 67:47-52. [DOI: 10.1016/j.enzmictec.2014.09.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 08/29/2014] [Accepted: 09/03/2014] [Indexed: 11/26/2022]
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19
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β-Glucosidase from Penicillium aculeatum hydrolyzes exo-, 3-O-, and 6-O-β-glucosides but not 20-O-β-glucoside and other glycosides of ginsenosides. Appl Microbiol Biotechnol 2013; 97:6315-24. [DOI: 10.1007/s00253-013-4828-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 01/22/2013] [Accepted: 03/02/2013] [Indexed: 10/27/2022]
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20
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Karnaouri A, Topakas E, Paschos T, Taouki I, Christakopoulos P. Cloning, expression and characterization of an ethanol tolerant GH3 β-glucosidase from Myceliophthora thermophila. PeerJ 2013; 1:e46. [PMID: 23638383 PMCID: PMC3628895 DOI: 10.7717/peerj.46] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 02/11/2013] [Indexed: 11/20/2022] Open
Abstract
The β-glucosidase gene bgl3a from Myceliophthora thermophila, member of the fungal glycosyl hydrolase (GH) family 3, was cloned and expressed in Pichia pastoris. The mature β-glucosidase gene, which results after the excision of one intron and the secreting signal peptide, was placed under the control of the strong alcohol oxidase promoter (AOX1) in the plasmid pPICZαC. The recombinant enzyme (90 kDa) was purified and characterized in order to evaluate its biotechnological potential. Recombinant P. pastoris efficiently secreted β-glucosidase into the medium and produced high level of enzymatic activity (41 U/ml) after 192 h of growth, under methanol induction. MtBgl3a was able to hydrolyze low molecular weight substrates and polysaccharides containing β-glucosidic residues. The Km was found to be 0.39 mM on p-β-NPG and 2.64 mM on cellobiose. Optimal pH and temperature for the p-β-NPG hydrolysis were 5.0 and 70 °C. The β-glucosidase exhibits a half life of 143 min at 60 °C. Kinetic parameters of inhibition were determined for D-glucose, D-xylose and D-gluconic acid, indicating tolerance of the enzyme for these sugars and oxidized products. The recombinant enzyme was stimulated by short chain alcohols and has been shown to efficiently synthesize methyl-D-glucoside in the presence of methanol due to its transglycosylation activity. The stability of MtBgl3a in ethanol was prominent, and it retained most of its original activity after we exposed it to 50% ethanol for 6 h. The high catalytic performance, good thermal stability and tolerance to elevated concentrations of ethanol, D-xylose and D-glucose qualify this enzyme for use in the hydrolysis of lignocellulosic biomass for biofuel production, as part of an efficient complete multi-enzyme cocktail.
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Affiliation(s)
- Anthi Karnaouri
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens , Athens , Greece
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21
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Singhania RR, Patel AK, Sukumaran RK, Larroche C, Pandey A. Role and significance of beta-glucosidases in the hydrolysis of cellulose for bioethanol production. BIORESOURCE TECHNOLOGY 2013; 127:500-7. [PMID: 23069613 DOI: 10.1016/j.biortech.2012.09.012] [Citation(s) in RCA: 323] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 09/05/2012] [Accepted: 09/05/2012] [Indexed: 05/02/2023]
Abstract
One of the major challenges in the bioconversion of lignocellulosic biomass into liquid biofuels includes the search for a glucose tolerant beta-gulucosidase. Beta-glucosidase is the key enzyme component present in cellulase and completes the final step during cellulose hydrolysis by converting the cellobiose to glucose. This reaction is always under control as it gets inhibited by its product glucose. It is a major bottleneck in the efficient biomass conversion by cellulase. To circumvent this problem several strategies have been adopted which we have discussed in the article along with its production strategies and general properties. It plays a very significant role in bioethanol production from biomass through enzymatic route. Hence several amendments took place in the commercial preparation of cellulase for biomass hydrolysis, which contains higher and improved beta-glucosidase for efficient biomass conversion. This article presents beta-glucosidase as the key component for bioethanol from biomass through enzymatic route.
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Affiliation(s)
- Reeta Rani Singhania
- Laboratoire de Génie Chimique et Biochimique, Université Blaise Pascal, Polytech Clermont-Ferrand, Aubiere cedex, France.
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22
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Li G, Jiang Y, Fan XJ, Liu YH. Molecular cloning and characterization of a novel β-glucosidase with high hydrolyzing ability for soybean isoflavone glycosides and glucose-tolerance from soil metagenomic library. BIORESOURCE TECHNOLOGY 2012; 123:15-22. [PMID: 22940294 DOI: 10.1016/j.biortech.2012.07.083] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 07/17/2012] [Accepted: 07/23/2012] [Indexed: 05/18/2023]
Abstract
A novel β-glucosidase (Bgl1269) was identified from a metagenomic library of mangrove soil by activity-based functional screening. Sequence analysis revealed that Bgl1269 encodes a protein of 422 amino acids. After being overexpressed in Escherichia coli and purified, the enzymatic properties of Bgl1269 were investigated. The recombinant enzyme displayed a pH optimum of 6.0 and a temperature optimum of 40°C, and the addition of most common metal ions (1 or 10mM) increased the enzymatic activity evidently. In addition, the enzyme showed high hydrolyzing ability for soybean isoflavone glycosides, and 0.8unit of enzyme could completely converted daidzin and genistin (0.5mg/mL) to daidzein and genistein at 40°C for 0.5h. Interestingly, Bgl1269 also exhibited a very high glucose-tolerance, with the highest inhibition constant K(i) (4.28M) among β-glucosidases reported so far. These properties make it a good candidate in the production of soybean isoflavone aglycones after further study.
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Affiliation(s)
- Gang Li
- School of life science, Sun Yat-sen University, Guangzhou 510275, PR China
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