1
|
Zeng M, Zhong Y, Guo Z, Yang H, Zhu H, Zheng L, Diao Y. Expression and Functional Study of BcWRKY1 in Baphicacanthus cusia (Nees) Bremek. FRONTIERS IN PLANT SCIENCE 2022; 13:919071. [PMID: 35845683 PMCID: PMC9284225 DOI: 10.3389/fpls.2022.919071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
Baphicacanthus cusia (Nees) Bremek (B. cusia) is an important medicinal plant. Its effective substances including indigo and indirubin are metabolites in indoleacetate metabolic pathway. Based on a previous transcriptome sequencing analysis, a WRKY transcription factor, BcWRKY1, in B. cusia was identified, showing significant correlation with effective substances from B. cusia. In this study, BcWRKY1 was cloned by reverse transcription-polymerase chain reaction (RT-PCR). Further analysis showed that the BcWRKY1 gene was 916 bp in length, containing three exons and two introns. The open reading frame (ORF) of BcWRKY1 was 534 bp in length and encoded a WRKY domain-containing protein with 177 amino acids residues. Subcellular localization showed that BcWRKY1 protein was mainly localized in the nucleus. It could bind to the W-box motif and its role in transcriptional activation was confirmed in yeast. The function of BcWRKY1 was investigated by overexpressing BcWRKY1 in Arabidopsis thaliana. Metabolic profiles in wild type and BcWRKY1-OX1 transgenic Arabidopsis thaliana were analyzed with LC-MS. Results showed that the metabolic profile was significantly changed in BcWRKY1-OX1 transgenic Arabidopsis thaliana compared with wild type. Furthermore, indole-related metabolites were significantly increased in BcWRKY1-OX1 transgenic Arabidopsis thaliana, and the metabolic pathway analysis showed that flavonoid biosynthesis was significantly enriched. Overexpression of BcWRKY1 significantly changed flavonoid and indole metabolism and indole-related metabolites were significantly upregulated. We postulated that the BcWRKY1 transcription factor might be involved in the regulation of effective substances metabolism in B. cusia.
Collapse
Affiliation(s)
- Meijuan Zeng
- School of Biomedical Sciences, Huaqiao University, Quanzhou, China
- Crops Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, China
| | - Yongjia Zhong
- Root Biology Center, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zhiying Guo
- School of Biomedical Sciences, Huaqiao University, Quanzhou, China
- Fujian Polytechnic Normal University, Fuqing, China
| | - Huiyong Yang
- School of Biomedical Sciences, Huaqiao University, Quanzhou, China
| | - Haisheng Zhu
- Crops Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, China
| | - Liling Zheng
- Department of Cardiovascular Surgery, First Hospital of Quanzhou Affiliated to Fujian Medical University, Quanzhou, China
| | - Yong Diao
- School of Biomedical Sciences, Huaqiao University, Quanzhou, China
| |
Collapse
|
2
|
Bonakdar A, Sahebazzamani F, Rasaee MJ, Hosseinkhani S, Rahbarizadeh F, Mahboudi F, Ganjali MR. In silico design and in vitro characterization of a recombinant antigen for specific recognition of NMP22. Int J Biol Macromol 2019; 140:69-77. [PMID: 31404598 DOI: 10.1016/j.ijbiomac.2019.08.065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/06/2019] [Accepted: 08/07/2019] [Indexed: 01/22/2023]
Abstract
Although urine cytology and cystoscopy are current gold standard methods in diagnosis and surveillance of Bladder cancer (BC), they have some limitations which necessitates novel diagnostic approaches to compensate their drawbacks. In this regard, Nuclear Matrix Protein 22 (NMP22) is introduced as a potential tumor biomarker for BC detection (FDA approved). NMP22 determination mainly occurs through immunoassay platforms, raising a proper antibody against its antigen. Hence, development of such immunoassays seems crucial. Various bioinformatic tools were harnessed to select a region with lowest variability, highest density for linear and conformational epitopes, lowest post translational modifications, highest antigenicity, best physicochemical properties and reliable transcriptional properties. Subsequently, E. coli BL21 (DE3) and P. pastoris GS115 were applied for exogenous expression. Ultimately, protein purification and quantification was followed by ELISA test for antibody analyses. Both host successfully expressed the antigen, while the E. coli expression was with higher yield. The commercial anti-NMP22 antibodies showed relatively equal detection results. However, the slight better detection for the antigen with P. pastoris origin could be deduced as better structural properties for P. pastoris. These results indicate higher expression yields and lower costs for over-expression of this eukaryotic antigen.
Collapse
Affiliation(s)
- Alireza Bonakdar
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Fatemeh Sahebazzamani
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mohammad Javad Rasaee
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Saman Hosseinkhani
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Fatemeh Rahbarizadeh
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | | | - Mohammad Reza Ganjali
- Center of Excellence in Electrochemistry, University of Tehran, Tehran, Iran; Biosensor Research Center, Endocrinology & Metabolism Molecular - Cellular Sciences Institute, Iran
| |
Collapse
|
3
|
Rykov SV, Kornberger P, Herlet J, Tsurin NV, Zorov IN, Zverlov VV, Liebl W, Schwarz WH, Yarotsky SV, Berezina OV. Novel endo-(1,4)-β-glucanase Bgh12A and xyloglucanase Xgh12B from Aspergillus cervinus belong to GH12 subgroup I and II, respectively. Appl Microbiol Biotechnol 2019; 103:7553-7566. [PMID: 31332485 DOI: 10.1007/s00253-019-10006-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/24/2019] [Accepted: 06/30/2019] [Indexed: 12/15/2022]
Abstract
In spite of intensive exploitation of aspergilli for the industrial production of carbohydrases, little is known about hydrolytic enzymes of fungi from the section Cervini. Novel glycoside hydrolases Bgh12A and Xgh12B from Aspergillus cervinus represent examples of divergent activities within one enzyme family and belong to the GH12 phylogenetic subgroup I (endo-(1,4)-β-glucanases) and II (endo-xyloglucanases), respectively. The bgh12A and xgh12B genes were identified in the unsequenced genome of A. cervinus using primers designed for conservative regions of the corresponding subgroups and a genome walking approach. The recombinant enzymes were heterologously produced in Pichia pastoris, purified, and characterized. Bgh12A was an endo-(1,4)-β-glucanase (EC 3.2.1.4) hydrolyzing the unbranched soluble β-(1,4)-glucans and mixed linkage β-(1,3;1,4)-D-glucans. Bgh12A exhibited maximum activity on barley β-glucan (BBG), which amounted to 614 ± 30 U/mg of protein. The final products of BBG and lichenan hydrolysis were glucose, cellobiose, cellotriose, 4-O-β-laminaribiosyl-glucose, and a range of higher mixed-linkage gluco-oligosaccharides. In contrast, the activity of endo-xyloglucanase Xgh12B (EC 3.2.1.151) was restricted to xyloglucan, with 542 ± 39 U/mg protein. The enzyme cleaved the (1,4)-β-glycosidic bonds of the xyloglucan backbone at the unsubstituted glucose residues finally generating cellotetraose-based hepta-, octa, and nona-oligosaccharides. Bgh12A and Xgh12B had maximal activity at 55 °C, pH 5.0. At these conditions, the half-time of Xgh12B inactivation was 158 min, whereas the half-life of Bgh12A was 5 min. Recombinant P. pastoris strains produced up to 106 U/L of the target enzymes with at least 75% of recombinant protein in the total extracellular proteins. The Bgh12A and Xgh12B sequences show 43% identity. Strict differences in substrate specificity of Bgh12A and Xgh12B were in congruence with the presence of subgroup-specific structural loops and substrate-binding aromatic residues in the catalytic cleft of the enzymes. Individual composition of aromatic residues in the catalytic cleft defined variability in substrate selectivity within GH12 subgroups I and II.
Collapse
Affiliation(s)
- Sergey V Rykov
- State Research Institute for Genetics and Selection of Industrial Microorganisms of National Research Center «Kurchatov Institute», 1-st Dorozhniy pr. 1, Moscow, Russian Federation, 117545
| | - Petra Kornberger
- Department of Microbiology, Technical University Munich, Emil-Ramann-Str. 4, 85354, Freising, Germany
| | - Jonathan Herlet
- Department of Microbiology, Technical University Munich, Emil-Ramann-Str. 4, 85354, Freising, Germany
| | - Nikita V Tsurin
- State Research Institute for Genetics and Selection of Industrial Microorganisms of National Research Center «Kurchatov Institute», 1-st Dorozhniy pr. 1, Moscow, Russian Federation, 117545
| | - Ivan N Zorov
- Russian Academy of Sciences, Federal Research Centre "Fundamentals of Biotechnology", Leninsky prospect, 33, build. 2, Moscow, 119071, Russian Federation
| | - Vladimir V Zverlov
- Department of Microbiology, Technical University Munich, Emil-Ramann-Str. 4, 85354, Freising, Germany
- Institute of Molecular Genetics, Russian Academy of Science, Kurchatov Sq. 2, Moscow, Russian Federation, 123182
| | - Wolfgang Liebl
- Department of Microbiology, Technical University Munich, Emil-Ramann-Str. 4, 85354, Freising, Germany
| | - Wolfgang H Schwarz
- Department of Microbiology, Technical University Munich, Emil-Ramann-Str. 4, 85354, Freising, Germany
| | - Sergey V Yarotsky
- State Research Institute for Genetics and Selection of Industrial Microorganisms of National Research Center «Kurchatov Institute», 1-st Dorozhniy pr. 1, Moscow, Russian Federation, 117545
| | - Oksana V Berezina
- State Research Institute for Genetics and Selection of Industrial Microorganisms of National Research Center «Kurchatov Institute», 1-st Dorozhniy pr. 1, Moscow, Russian Federation, 117545.
| |
Collapse
|
4
|
Rungrattanakasin B, Premjet S, Thanonkeo S, Klanrit P, Thanonkeo P. Cloning and expression of an endoglucanase gene from the thermotolerant fungus Aspergillus fumigatus DBiNU-1 in Kluyveromyces lactis. Braz J Microbiol 2018; 49:647-655. [PMID: 29449177 PMCID: PMC6066738 DOI: 10.1016/j.bjm.2017.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 09/30/2017] [Accepted: 10/14/2017] [Indexed: 11/24/2022] Open
Abstract
An intronless endoglucanase from thermotolerant Aspergillus fumigatus DBINU-1 was cloned, characterized and expressed in the yeast Kluyveromyces lactis. The full-length open reading frame of the endoglucanase gene from A. fumigatus DBiNU-1, designated Cel7, was 1383 nucleotides in length and encoded a protein of 460 amino acid residues. The predicted molecular weight and the isoelectric point of the A. fumigatus Cel7 gene product were 48.19 kDa and 5.03, respectively. A catalytic domain in the N-terminal region and a fungal type cellulose-binding domain/module in the C-terminal region were detected in the predicted polypeptide sequences. Furthermore, a signal peptide with 20 amino acid residues at the N-terminus was also detected in the deduced amino acid sequences of the endoglucanase from A. fumigatus DBiNU-1. The endoglucanase from A. fumigatus DBiNU-1 was successfully expressed in K. lactis, and the purified recombinant enzyme exhibited its maximum activity at pH 5.0 and 60 °C. The enzyme was very stable in a pH range from 4.0 to 8.0 and a temperature range from 30 to 60 °C. These features make it suitable for application in the paper, biofuel, and other chemical production industries that use cellulosic materials.
Collapse
Affiliation(s)
| | - Siripong Premjet
- Naresuan University, Faculty of Science, Department of Biology, Phitsanulok, Thailand
| | - Sudarat Thanonkeo
- Mahasarakham University, Walai Rukhavej Botanical Research Institute, Maha Sarakham, Thailand
| | - Preekamol Klanrit
- Khon Kaen University, Faculty of Technology, Department of Biotechnology, Khon Kaen, Thailand; Khon Kaen University, Faculty of Technology, Fermentation Research Center for Value Added Agricultural Products, Khon Kaen, Thailand
| | - Pornthap Thanonkeo
- Khon Kaen University, Faculty of Technology, Department of Biotechnology, Khon Kaen, Thailand; Khon Kaen University, Faculty of Technology, Fermentation Research Center for Value Added Agricultural Products, Khon Kaen, Thailand.
| |
Collapse
|
5
|
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.
Collapse
|
6
|
Wang J, Gao G, Li Y, Yang L, Liang Y, Jin H, Han W, Feng Y, Zhang Z. Cloning, Expression, and Characterization of a Thermophilic Endoglucanase, AcCel12B from Acidothermus cellulolyticus 11B. Int J Mol Sci 2015; 16:25080-95. [PMID: 26506341 PMCID: PMC4632791 DOI: 10.3390/ijms161025080] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 09/29/2015] [Accepted: 10/13/2015] [Indexed: 12/23/2022] Open
Abstract
The gene ABK52392 from the thermophilic bacterium Acidothermus cellulolyticus 11B was predicted to be endoglucanase and classified into glycoside hydrolase family 12. ABK52392 encodes a protein containing a catalytic domain and a carbohydrate binding module. ABK52392 was cloned and functionally expressed in Escherichia coli. After purification by Ni-NTA agarose affinity chromatography and Q-Sepharose® Fast Flow chromatography, the properties of the recombinant protein (AcCel12B) were characterized. AcCel12B exhibited optimal activity at pH 4.5 and 75 °C. The half-lives of AcCel12B at 60 and 70 °C were about 90 and 2 h, respectively, under acidic conditions. The specific hydrolytic activities of AcCel12B at 70 °C and pH 4.5 for sodium carboxymethylcellulose (CMC) and regenerated amorphous cellulose (RAC) were 118.3 and 104.0 U·mg−1, respectively. The Km and Vmax of AcCel12B for CMC were 25.47 mg·mL−1 and 131.75 U·mg−1, respectively. The time course of hydrolysis for RAC was investigated by measuring reducing ends in the soluble and insoluble phases. The total hydrolysis rate rapidly decreased after the early stage of incubation and the generation of insoluble reducing ends decreased earlier than that of soluble reducing ends. High thermostability of the cellulase indicates its potential commercial significance and it could be exploited for industrial application in the future.
Collapse
Affiliation(s)
- Junling Wang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
- Department of Biotechnology, Jilin Agricultural Science and Technology College, Jilin 132101, China.
| | - Gui Gao
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Yuwei Li
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.
| | - Liangzhen Yang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Yanli Liang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Hanyong Jin
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Weiwei Han
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Yan Feng
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Zuoming Zhang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| |
Collapse
|
7
|
Lü R, Zhao A, Li J, Liu C, Wang C, Wang X, Wang X, Pei R, Lu C, Yu M. Screening, cloning and expression analysis of a cellulase derived from the causative agent of hypertrophy sorosis scleroteniosis, Ciboria shiraiana. Gene 2015; 565:221-7. [PMID: 25865297 DOI: 10.1016/j.gene.2015.04.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 04/01/2015] [Accepted: 04/07/2015] [Indexed: 11/19/2022]
Abstract
A cellulase gene (KJ700939, CsCelA) from Ciboria shiraiana that is highly expressed during the infection of mulberry fruit was screened by quantitative real-time PCR (qRT-PCR). Using cDNA isolated from infected mulberry fruits as template, the full-length 1170-bp sequence of CsCelA was obtained, which encodes a 390-amino acid protein with a putative signal peptide of 24 amino acids. The 998-bp fragment encoding the mature peptide of CsCelA was cloned into the multiple cloning site of the pPIC9K vector and overexpressed as an active protein of 55.3kDa in the methylotrophic yeast Pichia pastoris. The specific activity of induced supernatants of the recombinant cellulase (CsCelA) was 17.44U/ml and 135U/g for freeze-dried powder. The Kmax and Vmax of CsCelA for sodium carboxymethylcellulose (CMC) were 4.6mg/ml and 107.2U/mg, respectively. The supernatant and freeze-dried powder of the recombinant cellulase exhibited stable activity from pH4.0 to 9.0, and at temperatures ranging from 30°C to 55°C. Finally, the activity of the recombinant cellulase was assessed by enzymatic hydrolysis of the cell walls of mulberry leaves. CsCelA showed an endo-cellulase mode of cleavage, as assessed by thin layer chromatography (TLC).
Collapse
Affiliation(s)
- Ruihua Lü
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China.
| | - Aichun Zhao
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Jun Li
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Changying Liu
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Chuanhong Wang
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Xiling Wang
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Xiaohong Wang
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Ruichao Pei
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Cheng Lu
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China
| | - Maode Yu
- The State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University Chong Qing, People's Republic of China.
| |
Collapse
|
8
|
Rawat R, Kumar S, Chadha BS, Kumar D, Oberoi HS. An acidothermophilic functionally active novel GH12 family endoglucanase from Aspergillus niger HO: purification, characterization and molecular interaction studies. Antonie van Leeuwenhoek 2014; 107:103-17. [DOI: 10.1007/s10482-014-0308-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Accepted: 10/15/2014] [Indexed: 11/29/2022]
|
9
|
Tang B, Zhang Y, Yang Y, Song Z, Li X. Expression and functional analysis of a glycoside hydrolase family 45 endoglucanase from Rhizopus stolonifer. World J Microbiol Biotechnol 2014; 30:2943-52. [PMID: 25164957 DOI: 10.1007/s11274-014-1722-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Accepted: 08/11/2014] [Indexed: 11/29/2022]
Abstract
A novel endoglucanase gene was cloned from Rhizopus stolonifer and expressed in Escherichia coli, the gene product EG II (45 kDa) was assigned to Glycoside Hydrolase Family 45 (GH45), and its specific activity on phosphoric acid-swollen cellulose (PASC) was 48 IU/mg. To solve the problem of substrate accumulation in the cellulose hydrolysis and enhance the catalytic efficiency of endoglucanase, the eg2 gene was modified by site directed mutagenesis. Mutations generated by overlapping PCR have been proven to increase its catalytic activity on carboxymenthyl cellulose, microcrystalline cellulose (Avicel) and PASC, among which the mutant EG II-E containing all 6 mutations (N39S, V136D, T251G, D255G, P256S and E260D) peaked 121 IU/mg on PASC. The bioinformatic analysis showed that 2 key catalytic residues (D136 and D260) moved closer with the opening of a loop after mutagenesis, and a tunnel was formed by structural transformation. This structure was conducive for the substrate to access the active centre, and D136 played an indispensable role in the substrate recognition.
Collapse
Affiliation(s)
- Bin Tang
- College of Biochemical Engineering, Anhui Polytechnic University, Wuhu, 241000, China,
| | | | | | | | | |
Collapse
|
10
|
Zhang HM, Wang JQ, Wu MC, Gao SJ, Li JF, Yang YJ. Optimized expression, purification and characterization of a family 11 xylanase (AuXyn11A) from Aspergillus usamii E001 in Pichia pastoris. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2014; 94:699-706. [PMID: 23881861 DOI: 10.1002/jsfa.6309] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 06/30/2013] [Accepted: 07/23/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND Xylanases have attracted much attention because of their potential applications. Unfortunately, the commercialization of xylanases is limited by their low catalytic activities. The aim of this study was to improve the activity of a xylanase by optimization of the expression conditions and to investigate its characterization. RESULTS The activity of recombinant AuXyn11A (reAuXyn11A), a family 11 xylanase from Aspergillus usamii E001 expressed in Pichia pastoris GS115, reached 912.6 U mL⁻¹ under the optimized conditions, which was 2.14 times as high as that expressed using the standard protocol. After the endogenous 18-aa propeptide had been processed in P. pastoris, reAuXyn11A (188-aa mature peptide) was secreted and purified with a specific activity of 22 714 U mg⁻¹. It displayed maximum activity at pH 5 and 50 °C and was stable in the pH range 4-8 and at a temperature of 45 °C or below. Its activity was not significantly affected by most metal ions and EDTA. Xylooligosaccharides ranging from xylobiose (X2) to xylohexaose (X6) were produced from insoluble corncob xylan by reAuXyn11A. CONCLUSION Its high specific activity and good enzymatic properties suggest that reAuXyn11A is a potential candidate for applications in industrial processes.
Collapse
Affiliation(s)
- Hui-Min Zhang
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122, China; Key Laboratory of Carbohydrate Chemistry & Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | | | | | | | | | | |
Collapse
|
11
|
Characterization and High Level Expression of Acidic Endoglucanase in Pichia pastoris. Appl Biochem Biotechnol 2013; 172:2253-65. [DOI: 10.1007/s12010-013-0672-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 12/03/2013] [Indexed: 10/25/2022]
|
12
|
Wang TY, Huang CJ, Chen HL, Ho PC, Ke HM, Cho HY, Ruan SK, Hung KY, Wang IL, Cai YW, Sung HM, Li WH, Shih MC. Systematic screening of glycosylation- and trafficking-associated gene knockouts in Saccharomyces cerevisiae identifies mutants with improved heterologous exocellulase activity and host secretion. BMC Biotechnol 2013; 13:71. [PMID: 24004614 PMCID: PMC3766678 DOI: 10.1186/1472-6750-13-71] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Accepted: 08/29/2013] [Indexed: 11/28/2022] Open
Abstract
Background As a strong fermentator, Saccharomyces cerevisiae has the potential to be an excellent host for ethanol production by consolidated bioprocessing. For this purpose, it is necessary to transform cellulose genes into the yeast genome because it contains no cellulose genes. However, heterologous protein expression in S. cerevisiae often suffers from hyper-glycosylation and/or poor secretion. Thus, there is a need to genetically engineer the yeast to reduce its glycosylation strength and to increase its secretion ability. Results Saccharomyces cerevisiae gene-knockout strains were screened for improved extracellular activity of a recombinant exocellulase (PCX) from the cellulose digesting fungus Phanerochaete chrysosporium. Knockout mutants of 47 glycosylation-related genes and 10 protein-trafficking-related genes were transformed with a PCX expression construct and screened for extracellular cellulase activity. Twelve of the screened mutants were found to have a more than 2-fold increase in extracellular PCX activity in comparison with the wild type. The extracellular PCX activities in the glycosylation-related mnn10 and pmt5 null mutants were, respectively, 6 and 4 times higher than that of the wild type; and the extracellular PCX activities in 9 protein-trafficking-related mutants, especially in the chc1, clc1 and vps21 null mutants, were at least 1.5 times higher than the parental strains. Site-directed mutagenesis studies further revealed that the degree of N-glycosylation also plays an important role in heterologous cellulase activity in S. cerevisiae. Conclusions Systematic screening of knockout mutants of glycosylation- and protein trafficking-associated genes in S. cerevisiae revealed that: (1) blocking Golgi-to-endosome transport may force S. cerevisiae to export cellulases; and (2) both over- and under-glycosylation may alter the enzyme activity of cellulases. This systematic gene-knockout screening approach may serve as a convenient means for increasing the extracellular activities of recombinant proteins expressed in S. cerevisiae.
Collapse
Affiliation(s)
- Tzi-Yuan Wang
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
High expression of a neutral endo-β-glucanase gene from Humicola insolens in Trichoderma reesei. ACTA ACUST UNITED AC 2013; 40:773-9. [DOI: 10.1007/s10295-013-1267-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Accepted: 04/01/2013] [Indexed: 10/26/2022]
Abstract
Abstract
The neutral endo-β-glucanase gene cel5A from Humicola insolens was cloned and connected with the cellobiohydrolase 1 promoter from Trichoderma reesei to construct a recombinant plasmid pCB-hEG with the hygromycin B resistance marker. The plasmid was introduced into conidia of T. reesei using the Agrobacterium tumefaciens mediated transformation method. Eight transformants were obtained on screening plates with sodium carboxymethyl cellulose as the sole carbon source. Stable integration of the cel5A gene into the chromosomal DNA of T. reesei was confirmed by PCR. An obvious protein band (approximately 52 kDa) was detected by SDS-PAGE from fermentation broth, which showed that the cel5A gene in recombinant T. reesei successfully fulfilled efficient expression and extracellular secretion. After 96 h shaking-flask fermentation, the endo-β-glucanase activity at pH 6.5 from recombinant T. reesei reached 3,068 U/ml, which was 11 times higher than that of the host strain. In a 2 m3 fermenter, the endo-β-glucanase activity could be further increased to 8,012 U/ml after 96 h fermentation. The results showed a good prospect for application of neutral endo-β-glucanase in the textile industry.
Collapse
|
14
|
Fusing a carbohydrate-binding module into the Aspergillus usamii β-mannanase to improve its thermostability and cellulose-binding capacity by in silico design. PLoS One 2013; 8:e64766. [PMID: 23741390 PMCID: PMC3669383 DOI: 10.1371/journal.pone.0064766] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 04/18/2013] [Indexed: 11/25/2022] Open
Abstract
The AuMan5A, an acidophilic glycoside hydrolase (GH) family 5 β-mannanase derived from Aspergillus usamii YL-01-78, consists of an only catalytic domain (CD). To perfect enzymatic properties of the AuMan5A, a family 1 carbohydrate-binding module (CBM) of the Trichoderma reesei cellobiohydrolase I (TrCBH I), having the lowest binding free energy with cellobiose, was selected by in silico design, and fused into its C-terminus forming a fusion β-mannanase, designated as AuMan5A-CBM. Then, its encoding gene, Auman5A-cbm, was constructed as it was designed theoretically, and expressed in Pichia pastoris GS115. SDS-PAGE analysis displayed that both recombinant AuMan5A-CBM (reAuMan5A-CBM) and AuMan5A (reAuMan5A) were secreted into the cultured media with apparent molecular masses of 57.3 and 49.8 kDa, respectively. The temperature optimum of the reAuMan5A-CBM was 75°C, being 5°C higher than that of the reAuMan5A. They were stable at temperatures of 68 and 60°C, respectively. Compared with reAuMan5A, the reAuMan5A-CBM showed an obvious decrease in Km and a slight alteration in Vmax. In addition, the fusion of a CBM of the TrCBH I into the AuMan5A contributed to its cellulose-binding capacity.
Collapse
|
15
|
Wang M, Mu Z, Wang J, Hou S, Han L, Dong Y, Xiao L, Xia R, Fang X. The identification of and relief from Fe3+ inhibition for both cellulose and cellulase in cellulose saccharification catalyzed by cellulases from Penicillium decumbens. BIORESOURCE TECHNOLOGY 2013; 133:507-512. [PMID: 23455222 DOI: 10.1016/j.biortech.2013.01.172] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 01/30/2013] [Accepted: 01/31/2013] [Indexed: 06/01/2023]
Abstract
Lignocellulosic biomass is an underutilized, renewable resource that can be converted to biofuels. The key step in this conversion is cellulose saccharification catalyzed by cellulase. In this work, the effect of metal ions on cellulose hydrolysis by cellulases from Penicillium decumbens was reported for the first time. Fe(3+) and Cu(2+) were shown to be inhibitory. Further studies on Fe(3+) inhibition showed the inhibition takes place on both enzyme and substrate levels. Fe(3+) treatment damages cellulases' capability to degrade cellulose and inhibits all major cellulase activities. Fe(3+) treatment also reduces the digestibility of cellulose, due to its oxidation. Treatment of Fe(3+)-treated cellulose with DTT and supplementation of EDTA to saccharification systems partially relieved Fe(3+) inhibition. It was concluded that Fe(3+) inhibition in cellulose degradation is a complicated process in which multiple inhibition events occur, and that relief from Fe(3+) inhibition can be achieved by the supplementation of reducing or chelating agents.
Collapse
Affiliation(s)
- Mingyu Wang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong 250100, China
| | | | | | | | | | | | | | | | | |
Collapse
|