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Ashoor S, Mathew GM, Sukumaran RK. Rice straw hydrolysis using in-situ produced enzymes: Feedstock influences fungal enzyme composition and hydrolytic efficiency. Prep Biochem Biotechnol 2024; 54:967-973. [PMID: 38327105 DOI: 10.1080/10826068.2024.2312458] [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] [Indexed: 02/09/2024]
Abstract
Trichoderma reesei RUT-C30 was cultivated on differentially pretreated rice straw and pure cellulose as a carbon source/inducer for cellulase production, and the enzymes were evaluated for hydrolysis of sequential acid and alkali pretreated rice straw. Growth on pretreated rice straw enhanced protein secretion and cellulase activities compared to pure cellulose as a carbon source. The yield of cellulolytic enzymes was higher for alkali pretreated rice straw (ALP-RS), while H2O2-treated (HP-RS) could not induce cellulases to a larger level compared to pure cellulose. Protein concentration was 3.5-fold higher on ALP-RS as compared to pure cellulose, with a maximum filter-paper cellulase (FPase) activity of 1.76 IU/ml and carboxy-methyl cellulase (CMCase) activity of 40.16 IU/ml (2.18 fold higher). Beta-glucosidase (BGL) activity was more or less the same with the different substrates and supplementation of heterologous BGL could result in a quantum jump in hydrolytic efficiencies, which in the case of ALP-RS induced enzymes was 34% (increased from 69.26% to 92.51%). The use of lignocellulosic biomass (LCB) itself as a substrate for the production of cellulase is advantageous not only in terms of raw material costs but also for obtaining a more suitable enzyme profile for biomass hydrolysis.
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Affiliation(s)
- Selim Ashoor
- Department of Agricultural Microbiology, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
| | - Gincy Marina Mathew
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram, India
| | - Rajeev K Sukumaran
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
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Liu X, Wang Y, Zhang R, Gao Y, Chen H, Dong S, Hu X. Insights into the transcriptomic mechanism and characterization of endoglucanases from Aspergillus terreus in cellulose degradation. Int J Biol Macromol 2024; 263:130340. [PMID: 38387642 DOI: 10.1016/j.ijbiomac.2024.130340] [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: 11/18/2023] [Revised: 02/12/2024] [Accepted: 02/19/2024] [Indexed: 02/24/2024]
Abstract
Filamentous fungi are the main industrial source of cellulases which are important in the process of converting cellulose to fermentable sugars. In this study, transcriptome analysis was conducted on Aspergillus terreus NEAU-7 cultivated using corn stover and glucose as carbon sources. Four putative endoglucanases (EG5A, EG7A, EG12A, and EG12C) from A. terreus NEAU-7 were efficiently expressed in Pichia pastoris. Among them, EG7A exhibited the highest enzyme activity (75.17 U/mg) with an optimal temperature of 40 °C and pH 5.0. EG5A and EG12A displayed specific activities of 19.92 U/mg and 14.62 U/mg, respectively, at 50 °C. EG12C showed acidophilic characteristics with an optimal pH of 3.0 and a specific activity of 12.21 U/mg at 40 °C. With CMC-Na as the substrate, the Km value of EG5A, EG7A, EG12A or, EG12C was, 11.08 ± 0.87 mg/mL, 6.82 ± 0.74 mg/mL, 7.26 ± 0.64 mg/mL, and 9.88 ± 0.86 mg/mL, with Vmax values of 1258.23 ± 51.62 μmol∙min-1∙mg-1, 842.65 ± 41.53 μmol∙min-1∙mg-1, 499.38 ± 20.42 μmol∙min-1∙mg-1, and 681.41 ± 30.08 μmol∙min-1∙mg-1, respectively. The co-treatment of EG7A with the commercial cellulase increased the yield of reducing sugar by 155.77 % (filter paper) and 130.49 % (corn stover). Molecular docking assay showed the interaction energy of EG7A with cellotetraose at -10.50 kcal/mol, surpassing EG12A (-10.43 kcal/mol), EG12C (-10.28 kcal/mol), and EG5A (-9.00 kcal/mol). Root Mean Square Deviation (RMSD) and Solvent Accessible Surface Area (SASA) values revealed that the presence of cellotetraose stabilized the molecular dynamics simulation of the cellotetraose-protein complex over a 100 ns time scale. This study provides valuable insights for developing recombinant enzymes and biomass degradation technologies.
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Affiliation(s)
- Xin Liu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Yanbo Wang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Rui Zhang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Yunfei Gao
- Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China
| | - Heshu Chen
- Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China
| | | | - Xiaomei Hu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China.
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Ali NS, Huang F, Qin W, Yang TC. A high throughput screening process and quick isolation of novel lignin-degrading microbes from large number of natural biomasses. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2023; 39:e00809. [PMID: 37583477 PMCID: PMC10423689 DOI: 10.1016/j.btre.2023.e00809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/14/2023] [Accepted: 07/26/2023] [Indexed: 08/17/2023]
Abstract
High throughput screening approaches can significantly speed up the identification of novel enzymes from natural microbial consortiums. A two-step high throughput screening process was proposed and explored to screen lignin-degrading microorganisms. By employing this modified culture enrichment method and screening based on enzyme activity, a total of 82 bacterial and 46 fungal strains were isolated from fifty decayed wood samples (100 liquid cultures) collected from the banks of the Ottawa River in Canada. Among them, ten bacterial and five fungal strains were selected and identified based on their high laccase activities by 16S rDNA and ITS gene sequencing, respectively. The study identified bacterial strains from various genera including Serratia, Enterobacter, Raoultella, and Bacillus, along with fungal counterparts including Mucor, Trametes, Conifera and Aspergillus. Moreover, Aspergillus sydowii (AORF21), Mucor sp. (AORF43), Trametes versicolor (AORF3) and Enterobacter sp. (AORB55) exhibited xylanase and β- glucanase activities in addition to laccase production. The proposed approach allowed for the quick identification of promising consortia and enhanced the chance of isolating desired strains based on desired enzyme activities. This method is not limited to lignocellulose and lignin-degrading microorganisms but can be applied to identify novel microbial strains and enzymes from different natural samples.
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Affiliation(s)
- Nadia Sufdar Ali
- Department of Biology, Lakehead University, Thunder Bay, ON, Canada
- Aquatic and Crop Resource Development Research Centre, National Research Council, Ottawa, ON, Canada
| | - Fang Huang
- Aquatic and Crop Resource Development Research Centre, National Research Council, Ottawa, ON, Canada
| | - Wensheng Qin
- Department of Biology, Lakehead University, Thunder Bay, ON, Canada
| | - Trent Chunzhong Yang
- Aquatic and Crop Resource Development Research Centre, National Research Council, Ottawa, ON, Canada
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Arif S, Nait M’Barek H, Oulghazi S, Audenaert K, Hajjaj H. Lignocellulose-degrading fungi newly isolated from central Morocco are potent biocatalysts for olive pomace valorization. Arch Microbiol 2022; 204:704. [DOI: 10.1007/s00203-022-03318-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/18/2022] [Accepted: 11/01/2022] [Indexed: 11/15/2022]
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Indumathi T, Jayaraj R, Kumar PS, Sonali J MI, Krishnaswamy VG, Ghfar AA, Govindaraju S. Biological approach in deinking of waste paper using bacterial cellulase as an effective enzyme catalyst. CHEMOSPHERE 2022; 287:132088. [PMID: 34509023 DOI: 10.1016/j.chemosphere.2021.132088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Paper has become the basic elixir in everyone's activities and usage of paper has increased day by day, the waste generated by paper is also enormous. The primary source of paper is wood (tree) yet, waste paper is environmentally good and biodegradable; however, it is the primary source of deforestation. Current research aims to find an alternate way to recycle paper in the biological approach. Hence in our work, twelve cellulose-producing bacteria were isolated, out of which one bacterial strain proved to be the best. Cellulase enzyme was extracted and purified, and used for enzymatic de-inking of photocopy papers. The optimal conditions for cellulase synthesis were at 60 °C, glucose as the only carbon source, and potassium nitrate as the nitrogen source. The enzyme demonstrated excellent de-inking at a lower pulp consistency of 3% with a 20% enzyme dose. The cellulose and hemicellulose levels decreased, which can be attributed to fiber breaking. Further, the changes in the functional groups identified by Fourier-transform infrared spectroscopy analysis and the changes in the surface morphology of the pulp fibers were obtained using scanning electron microscope analysis.
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Affiliation(s)
- T Indumathi
- Department of Zoology, Stella Maris College, Chennai, 600 086, Tamil Nadu, India
| | - Rita Jayaraj
- Department of Zoology, Stella Maris College, Chennai, 600 086, Tamil Nadu, India
| | - P Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, Chennai, 603 110, India; Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, Chennai, 603 110, India.
| | | | | | - Ayman A Ghfar
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
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Waghmare PR, Waghmare PP, Gao L, Sun W, Qin Y, Liu G, Qu Y. Efficient Constitutive Expression of Cellulolytic Enzymes in Penicillium oxalicum for Improved Efficiency of Lignocellulose Degradation. J Microbiol Biotechnol 2021; 31:740-746. [PMID: 33746194 PMCID: PMC9705867 DOI: 10.4014/jmb.2101.01003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/05/2021] [Accepted: 03/10/2021] [Indexed: 12/15/2022]
Abstract
Efficient cellulolytic enzyme production is important for the development of lignocellulose-degrading enzyme mixtures. However, purification of cellulases from their native hosts is time- and labor-consuming. In this study, a constitutive expression system was developed in Penicillium oxalicum for the secreted production of proteins. Using a constitutive polyubiquitin gene promoter and cultivating with glucose as the sole carbon source, nine cellulolytic enzymes of different origins with relatively high purity were produced within 48 h. When supplemented to a commercial cellulase preparation, cellobiohydrolase I from P. funiculosum and cellobiohydrolase II from Talaromyces verruculosus showed remarkable enhancing effects on the hydrolysis of steam-exploded corn stover. Additionally, a synergistic effect was observed for these two cellobiohydrolases during the hydrolysis. Taken together, the constitutive expression system provides a convenient tool for the production of cellulolytic enzymes, which is expected to be useful in the development of highly efficient lignocellulose-degrading enzyme mixtures.
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Affiliation(s)
| | | | - Liwei Gao
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Shandong 266101, P. R. China
| | - Wan Sun
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China
| | - Yuqi Qin
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China
| | - Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China,Corresponding author Phone: +86-532-58632406 Fax: +86-532-58631501 E-mail:
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China
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