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Wang YC, Ma JW, Liu HJ, Jiang ZQ, Li YX. Simultaneous improvement of thermostability and maltotriose-forming ability of a fungal α-amylase for bread making by directed evolution. Int J Biol Macromol 2024; 264:130481. [PMID: 38431017 DOI: 10.1016/j.ijbiomac.2024.130481] [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: 08/04/2023] [Revised: 02/03/2024] [Accepted: 02/26/2024] [Indexed: 03/05/2024]
Abstract
For applications in food industries, a fungal α-amylase from Malbranchea cinnamomea was engineered by directed evolution. Through two rounds of screening, a mutant α-amylase (mMcAmyA) was obtained with higher optimal temperature (70 °C, 5 °C increase) and better hydrolysis properties (18.6 % maltotriose yield, 2.5-fold increase) compared to the wild-type α-amylase (McAmyA). Site-directed mutations revealed that Threonine (Thr) 226 Serine (Ser) substitution was the main reason for the property evolution of mMcAmyA. Through high cell density fermentation, the highest expression level of Thr226Ser was 3951 U/mL. Thr226Ser was further used for bread baking with a dosage of 1000 U/kg flour, resulting in a 17.8 % increase in specific volume and a 35.6 % decrease in hardness compared to the control. The results were a significant improvement on those of McAmyA. Moreover, the mutant showed better anti-staling properties compared to McAmyA, as indicated by the improved sensory evaluation after 4 days of storage at 4 and 25 °C. These findings provide insights into the structure-function relationship of fungal α-amylase and introduce a potential candidate for bread-making industry.
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Affiliation(s)
- Yu-Chuan Wang
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, 100083, China
| | - Jun-Wen Ma
- Bioresource Utilization Laboratory, College of Engineering, China Agricultural University, Beijing 100083, China
| | - Hai-Jie Liu
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, 100083, China.
| | - Zheng-Qiang Jiang
- Key Laboratory of Food Bioengineering (China National Light Industry), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, 100083, China; College of Food Science and Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Yan-Xiao Li
- Bioresource Utilization Laboratory, College of Engineering, China Agricultural University, Beijing 100083, China; Food Laboratory of Zhongyuan, Luohe 462000, China.
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Muniasamy R, Rathnasaamy S. Sustainable production and preparative purification of thermostable alkaline α-amylase by Bacillus simplex (ON754233) employing natural deep eutectic solvent-based extractive fermentation. Sci Rep 2024; 14:481. [PMID: 38177253 PMCID: PMC10766970 DOI: 10.1038/s41598-024-51168-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 01/01/2024] [Indexed: 01/06/2024] Open
Abstract
Using PEG-based deep eutectic solvents (PDES), the current study proposes extractive fermentation as a sustainable process integration for the production and purification of α-amylase from Bacillus simplex (ON754233). Glucose: PEG 400 outperformed five PDES in terms of tie lie length (58) and slope value (1.23) against sodium sulphatt. Apple cider pomace was used as a low-cost, sustainable carbon source to produce-amylase, with a maximum enzyme production of 2200.13 U/mL. PDES concentration (20% w/v), salt (12.75 w/v), and apple waste (2.75 g/mL) were all optimized using response surface methodology. When scaled upto 3 L benchtop bioreactor, extractive fermentation was proved to be better technology with maximum recovery of 92.4% with highest partition coefficient (3.59). The partially purified enzyme was further purified using a Sephadex G 100 followed by DEAE-Sephadex anion exchange chromatography with a purity fold of 33. The enzyme was found to be thermostable at the temperature (60 °C), remains alkaline (pH 8), and the activity was stimulated in the presence of Mg2+ ions. With SDS PAGE electrophoresis, the molecular weight was found to be around 140 kDa. Finally, the enzyme kinetics parameters were evaluated with observed Km (0.00396 mM) and Vmax (37.87 U/mL). Thus scaling up extractive fermentation entails increasing production capacity with improved extraction efficiency using green solvents.
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Affiliation(s)
- Ramya Muniasamy
- Green Separation Engineering Laboratory, School of Chemical and Biotechnology, SASTRA Deemed to Be University, Thanjavur, Tamilnadu, India
| | - Senthilkumar Rathnasaamy
- Green Separation Engineering Laboratory, School of Chemical and Biotechnology, SASTRA Deemed to Be University, Thanjavur, Tamilnadu, India.
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Phetlum S, Champasri C. Purification and characterization of amylases from three freshwater fish species providing new insight application as enzyme molecular markers for zymography. FISH PHYSIOLOGY AND BIOCHEMISTRY 2023; 49:1257-1276. [PMID: 37889390 DOI: 10.1007/s10695-023-01255-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023]
Abstract
Purification of amylases from digestive tracts of three freshwater fish species with Q-Sepharose Fast Flow and Sephacryl S-200 columns displayed two isoforms of amylases from Osteochilus hasselti (O1, O2) and three isoforms of those from both Hampala dispar (UB, H1, H2) and Puntioplites proctozystron (P1, P2, P3). The optimum pH values displayed at 7.0 and 8.0, while the optimum temperatures revealed at 40 and 50 °C. Almost isoenzyme activities were activated by NaCl and CaCl2, whereas EDTA and SDS strongly inhibited all enzymatic activities. Verification with an atomic absorption spectrophotometry exhibited the presence of Ca2+ ions in the range of 0.02-13.53 ppm per mg protein indicating that amylases are Ca2+ dependent. Molecular weight analysis revealed 12 to 147 kDa. The UB, O1, and H2 amylases with appropriate molecular masses of 64, 49, and 25 kDa validated with LC-MS/MS were selected. Three certain enzymes revealed high stability in a sample buffer after five cycles of freeze-thawing process upon storage at - 20 °C for 12 weeks. No protein degradation was observed on polyacrylamide gel, and the enzymes still displayed sharp and clear bands on zymograms. The result suggested that the purified fish amylases, which expressed high activities and stabilities, were potentially used as enzyme molecular weight markers for zymography.
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Affiliation(s)
- Suthathip Phetlum
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Chamaiporn Champasri
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen, 40002, Thailand.
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Mendonça APS, Dos Reis KL, Barbosa-Tessmann IP. Aspergillus clavatus UEM 04: An efficient producer of glucoamylase and α-amylase able to hydrolyze gelatinized and raw starch. Int J Biol Macromol 2023; 249:125890. [PMID: 37479205 DOI: 10.1016/j.ijbiomac.2023.125890] [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: 02/25/2023] [Revised: 06/04/2023] [Accepted: 07/17/2023] [Indexed: 07/23/2023]
Abstract
The best amylolytic activity production by Aspergillus clavatus UEM 04 occurred in submersed culture, with starch, for 72 h, at 25 °C, and 100 rpm. Exclusion chromatography partially purified two enzymes, which ran as unique bands in SDS-PAGE with approximately 84 kDa. LC-MS/MS identified a glucoamylase (GH15) and an α-amylase (GH13_1) as the predominant proteins and other co-purified proteins. Zn2+, Cu2+, and Mn2+ activated the glucoamylase, and SDS, Zn2+, Fe3+, and Cu2+ inhibited the α-amylase. The α-amylase optimum pH was 6.5. The optimal temperatures for the glucoamylase and α-amylase were 50 °C and 40 °C, and the Tm was 53.1 °C and 56.3 °C, respectively. Both enzymes remained almost fully active for 28-32 h at 40 °C, but the α-amylase thermal stability was calcium-dependent. Furthermore, the glucoamylase and α-amylase KM for starch were 2.95 and 1.0 mg/mL, respectively. Still, the Vmax was 0.28 μmol/min of released glucose for glucoamylase and 0.1 mg/min of consumed starch for α-amylase. Moreover, the glucoamylase showed greater affinity for amylopectin and α-amylase for maltodextrin. Additionally, both enzymes efficiently degraded raw starch. At last, glucose was the main product of glucoamylase, and α-amylase produced mainly maltose from gelatinized soluble starch hydrolysis.
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Affiliation(s)
- Ana Paula Silva Mendonça
- Biological Sciences Center, Department of Biochemistry, Universidade Estadual de Maringá, Maringá, PR, Brazil
| | - Karina Lima Dos Reis
- Biological Sciences Center, Department of Biochemistry, Universidade Estadual de Maringá, Maringá, PR, Brazil
| | - Ione Parra Barbosa-Tessmann
- Biological Sciences Center, Department of Biochemistry, Universidade Estadual de Maringá, Maringá, PR, Brazil.
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Bamigboye CO, Okonji RE, Oluremi IO, James V. Stain removing, juice-clarifying, and starch-liquefying potentials of amylase from Pleurotus tuberregium in submerged fermentation system. J Genet Eng Biotechnol 2022; 20:23. [PMID: 35142943 PMCID: PMC8831669 DOI: 10.1186/s43141-022-00298-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 01/07/2022] [Indexed: 11/10/2022]
Abstract
Background Amylase is used commercially in food, textiles, sugar syrup, paper, and detergent industries. Bacteria and fungi remain a significant source of industrial enzymes. Pleurotus tuberregium is a macro-fungi that can exist as a fruiting body, sclerotium, mycelium, and spores. Some studies have been conducted on this fungus, with minimal studies on its enzyme activity (s) using the submerged fermentation technique. Results The purified amylase has a specific activity of 5.26 U/mg, total activity of 189.20 U, maximally active at 70 °C, pH of 5, and retaining 100% of its activity at 30 oC for 4 min. P. tuberregium amylase showed optimal activity with plantain peel, followed by starch and pineapple peel (42, 30, and 29 μg/mL/min respectively). The presence of Ca2+, Mg2+, and Na+ ions in the reaction mixture activated the enzyme activity, but was slightly and moderately inhibited by KCl and Na2H2PO4 respectively. The crude enzyme effectively clarified juice, liquefied soluble cassava starch (with a release of appreciable glucose quantity), and partially de-stained white fabric. Conclusions The amylase obtained from the submerged fermentation of Pleurotus tuberregium has potential applications in food and detergent industries.
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Affiliation(s)
- Comfort Olukemi Bamigboye
- Microbiology Unit, Department of Pure and Applied Biology, Ladoke Akintola University of Technology, Ogbomoso, P.M.B. 4000, Nigeria.
| | - Raphael E Okonji
- Department of Biochemistry and Molecular Biology, Obafemi Awolowo University, Ile-Ife, Nigeria
| | - Iyanu Oluwalonimi Oluremi
- Microbiology Unit, Department of Pure and Applied Biology, Ladoke Akintola University of Technology, Ogbomoso, P.M.B. 4000, Nigeria
| | - Victoria James
- Microbiology Unit, Department of Pure and Applied Biology, Ladoke Akintola University of Technology, Ogbomoso, P.M.B. 4000, Nigeria
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Yang H, Yang X, Ning Z, Kwon SY, Li ML, Tack FMG, Kwon EE, Rinklebe J, Yin R. The beneficial and hazardous effects of selenium on the health of the soil-plant-human system: An overview. JOURNAL OF HAZARDOUS MATERIALS 2022; 422:126876. [PMID: 34416699 DOI: 10.1016/j.jhazmat.2021.126876] [Citation(s) in RCA: 63] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/25/2021] [Accepted: 08/07/2021] [Indexed: 06/13/2023]
Abstract
Selenium (Se), which can be both hazardous and beneficial to plants, animals and humans, plays a pivotal role in regulating soil-plant-human ecosystem functions. The biogeochemical behavior of Se and its environmental impact on the soil-plant-human system has received broad attention in the last decades. This review provides a comprehensive understanding of Se biogeochemistry in the soil-plant-human system. The speciation, transformation, bioavailability as well as the beneficial and hazardous effects of Se in the soil-plant-human system are summarized. Several important aspects in Se in the soil-plant-human system are detailed mentioned, including (1) strategies for biofortification in Se-deficient areas and phytoremediation of soil Se in seleniferous areas; (2) factors affecting Se uptake and transport by plants; (3) metabolic pathways of Se in the human body; (4) the interactions between Se and other trace elements in plant and animals, in particular, the detoxification of heavy metals by Se. Important research hotspots of Se biogeochemistry are outlined, including (1) the coupling of soil microbial activity and the Se biogeochemical cycle; (2) the molecular mechanism of Se metabolic in plants and animals; and (3) the application of Se isotopes as a biogeochemical tracer in research. This review provides up-to-date knowledge and guidelines on Se biogeochemistry research.
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Affiliation(s)
- Hui Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Guizhou Academy of Tobacco Science, 550081 Guiyang, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuefeng Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zengping Ning
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Sae Yun Kwon
- Division of Environmental Science & Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam Gu, Pohang 37673, South Korea
| | - Mi-Ling Li
- School of Marine Science and Policy, University of Delaware, Newark, DE 19716 USA
| | - Filip M G Tack
- Ghent University, Department of Green Chemistry and Technology, Ghent, Belgium
| | - Eilhann E Kwon
- Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Guangjin-Gu, Seoul, Republic of Korea
| | - Jörg Rinklebe
- Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Guangjin-Gu, Seoul, Republic of Korea; University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water and Waste Management, Laboratory of Soil and Groundwater Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany
| | - Runsheng Yin
- State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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7
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Oyedeji O, Olakusehin VO, Okonji RE. A thermostable extracellular α-amylase from Aspergillus flavus S2-OY: Purification, characterisation and application in raw starch hydrolysis. BIOCATAL BIOTRANSFOR 2021. [DOI: 10.1080/10242422.2021.2005032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Olaoluwa Oyedeji
- Department of Microbiology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Nigeria
| | | | - Raphael Emuebie Okonji
- Department of Biochemistry and Molecular Biology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Nigeria
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Kalia S, Bhattacharya A, Prajapati SK, Malik A. Utilization of starch effluent from a textile industry as a fungal growth supplement for enhanced α-amylase production for industrial application. CHEMOSPHERE 2021; 279:130554. [PMID: 33873067 DOI: 10.1016/j.chemosphere.2021.130554] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 03/19/2021] [Accepted: 04/07/2021] [Indexed: 06/12/2023]
Abstract
Desizing process in textile industry produces large volume of starch effluent. This carbon-rich waste can be used for resource recovery, such as the production of industrially useful enzymes. The present work assesses the usability of starch effluent from textile industry as an additional carbon source for enhanced production of α-amylase during solid-state fermentation (SSF) of agro-wastes by Trichoderma reesei. A significant increase (p ≤ 0.05) in α-amylase activity (25.48 ± 1.12 U mL-1) was observed with supplementation of starch effluent in SSF. Partial purification of α-amylase by 80% ammonium sulphate precipitation produced a yield of 58.39% enzyme with purification fold of 1.89. The enzyme was thermally stable at 40 °C with 90% residual activity after 5 h and 70% residual activity at 50 °C after 3 h. Using Michaelis-Menten kinetics analysis, the estimated Km and Vmax values for the partially purified α-amylase were found to be 2.55 mg mL-1 and 53.47 U mg-1, respectively. For the rapid assessment of the industrial application, desizing of the fabric was attempted. The cotton fabric was efficiently desized using α-amylase (at a concentration of 1% on the weight of fabric basis) at 80 °C. The present work demonstrates starch effluent from desizing process as a resource for the production of amylase. The amylase can further be used in the desizing process. With in-depth research, the work may lead to the development of a closed-loop, waste-recycling process for the textile industry.
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Affiliation(s)
- Shweta Kalia
- Applied Microbiology Lab, Centre for Rural Development and Technology, Indian Institute of Technology Delhi, 110016, India.
| | - Arghya Bhattacharya
- Applied Microbiology Lab, Centre for Rural Development and Technology, Indian Institute of Technology Delhi, 110016, India; Department of Biotechnology, Gandhi Institute of Engineering and Technology University, Gunupur, Odisha, 765022, India.
| | - Sanjeev Kumar Prajapati
- Environment and Biofuel Research Lab, Department of Hydro and Renewable Energy, Indian Institute of Technology, Roorkee, Uttarakhand, 247667, India.
| | - Anushree Malik
- Applied Microbiology Lab, Centre for Rural Development and Technology, Indian Institute of Technology Delhi, 110016, India.
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Structure Prediction of a Thermostable SR74 α-Amylase from Geobacillus stearothermophilus Expressed in CTG-Clade Yeast Meyerozyma guilliermondii Strain SO. Catalysts 2020. [DOI: 10.3390/catal10091059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
α-amylase which catalyzes the hydrolysis of α-1,4-glycosidic bonds in starch have frequently been cloned into various microbial workhorses to yield a higher recombinant titer. A thermostable SR74 α-amylase from Geobacillus stearothermophilus was found to have a huge potential in detergent industries due to its thermostability properties. The gene was cloned into a CTG-clade yeast Meyerozyma guilliermondii strain SO. However, the CUG ambiguity present in the strain SO has possibly altered the amino acid residues in SR74 amylase wild type (WT) encoded by CUG the codon from the leucine to serine. From the multiple sequence alignment, six mutations were found in recombinant SR74 α-amylase (rc). Their effects on SR74 α-amylase structure and function remain unknown. Herein, we predicted the structures of the SR74 amylases (WT and rc) using the template 6ag0.1.A (PDB ID: 6ag0). We sought to decipher the possible effects of CUG ambiguity in strain SO via in silico analysis. They are structurally identical, and the metal triad (CaI–CaIII) might contribute to the thermostability while CaIV was attributed to substrate specificity. Since the pairwise root mean square deviation (RMSD) between the WT and rc SR74 α-amylase was lower than the template, we suggest that the biochemical properties of rc SR74 α-amylase were better deduced from its WT, especially its thermostability.
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10
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Elyasi Far B, Ahmadi Y, Yari Khosroshahi A, Dilmaghani A. Microbial Alpha-Amylase Production: Progress, Challenges and Perspectives. Adv Pharm Bull 2020; 10:350-358. [PMID: 32665893 PMCID: PMC7335993 DOI: 10.34172/apb.2020.043] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 10/23/2019] [Accepted: 11/09/2019] [Indexed: 11/24/2022] Open
Abstract
Alpha-amylase reputes for starch modification by breaking of 1-4 glycosidic bands and is widely applied in different industrial sectors. Microorganisms express unique alpha-amylases with thermostable and halotolerant characteristics dependent on the microorganism’s intrinsic features. Likewise, genetic engineering methods are applied to produce enzymes with higher stability in contrast to wild types. As there are widespread application of α-amylase in industry, optimization methods like RSM are used to improve the production of the enzyme ex vivo. This study aimed to review the latest researches on the production improvement and stability of α-amylase.
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Affiliation(s)
- Babak Elyasi Far
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yassin Ahmadi
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ahmad Yari Khosroshahi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Medical Nanotechnology, Faculty of Advanced Medical Science, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Azita Dilmaghani
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Karim KMR, Husaini A, Sing NN, Tasnim T, Mohd Sinang F, Hussain H, Hossain MA, Roslan H. Characterization and expression in Pichia pastoris of a raw starch degrading glucoamylase (GA2) derived from Aspergillus flavus NSH9. Protein Expr Purif 2019; 164:105462. [PMID: 31351992 DOI: 10.1016/j.pep.2019.105462] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 06/19/2019] [Accepted: 07/24/2019] [Indexed: 11/25/2022]
Abstract
The Aspergillus flavus NSH9 gene, encoding a pH and thermostable glucoamylase with a starch binding domain (SBD), was expressed in Pichia pastoris to produce recombinant glucoamylase (rGA2). The full-length glucoamylase gene (2039 bp), and cDNA (1839 bp) encode a 612 amino acid protein most similar to glucoamylase from Aspergillus oryzae RIB40; the first 19 amino acids are presumed to be a signal peptide for secretion, and the SBD is at the C-terminal. The cDNA was successfully secreted by Pichia at 8.23 U mL-1, and the rGA2 was found to be: a 80 kDa monomer, stable from pH 3.0-9.0, with optimum catalytic activity at pH 5.0, active at temperatures up to 80°C (rGA2 retained 58% of its activity after 60 min of incubation at 70°C), and metal ions such as Na+, K+, Ca++ and Mg++ enhanced rGA2 enzyme activity. The starch degrading ability of rGA2 was also observed on raw sago starch and where prolonged incubation generated larger, deeper, holes on the starch granules, indicating rGA2 is an excellent candidate for industrial starch processing applications.
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Affiliation(s)
| | - Ahmad Husaini
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300, Kota, Samarahan, Sarawak, Malaysia.
| | - Ngieng Ngui Sing
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300, Kota, Samarahan, Sarawak, Malaysia
| | - Tasmia Tasnim
- Department of Nutrition and Food Engineering, Daffodil International University, Dhaka, 1207, Bangladesh
| | - Fazia Mohd Sinang
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300, Kota, Samarahan, Sarawak, Malaysia
| | - Hasnain Hussain
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300, Kota, Samarahan, Sarawak, Malaysia
| | - Md Anowar Hossain
- Department of Biochemistry and Molecular Biology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Hairul Roslan
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300, Kota, Samarahan, Sarawak, Malaysia
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12
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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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13
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Chen Z, Zaky AA, Liu Y, Chen Y, Liu L, Li S, Jia Y. Purification and characterization of a new xylanase with excellent stability from Aspergillus flavus and its application in hydrolyzing pretreated corncobs. Protein Expr Purif 2019; 154:91-97. [DOI: 10.1016/j.pep.2018.10.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/01/2018] [Accepted: 10/10/2018] [Indexed: 12/31/2022]
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