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Ashok PP, Dasgupta D, Ray A, Suman SK. Challenges and prospects of microbial α-amylases for industrial application: a review. World J Microbiol Biotechnol 2023; 40:44. [PMID: 38114825 DOI: 10.1007/s11274-023-03821-y] [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: 08/29/2023] [Accepted: 10/27/2023] [Indexed: 12/21/2023]
Abstract
α-Amylases are essential biocatalysts representing a billion-dollar market with significant long-term global demand. They have varied applications ranging from detergent, textile, and food sectors such as bakery to, more recently, biofuel industries. Microbial α-amylases have distinct advantages over their plant and animal counterparts owing to generally good activities and better stability at temperature and pH extremes. With the scope of applications expanding, the need for new and improved α-amylases is ever-growing. However, scaling up microbial α-amylase technology from the laboratory to industry for practical applications is impeded by several issues, ranging from mass transfer limitations, low enzyme yields, and energy-intensive product recovery that adds to high production costs. This review highlights the major challenges and prospects for the production of microbial α-amylases, considering the various avenues of industrial bioprocessing such as culture-independent approaches, nutrient optimization, bioreactor operations with design improvements, and product down-streaming approaches towards developing efficient α-amylases with high activity and recyclability. Since the sequence and structure of the enzyme play a crucial role in modulating its functional properties, we have also tried to analyze the structural composition of microbial α-amylase as a guide to its thermodynamic properties to identify the areas that can be targeted for enhancing the catalytic activity and thermostability of the enzyme through varied immobilization or selective enzyme engineering approaches. Also, the utilization of inexpensive and renewable substrates for enzyme production to isolate α-amylases with non-conventional applications has been briefly discussed.
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Affiliation(s)
- Patel Pratima Ashok
- Biochemistry and Biotechnology Area, Material Resource Efficiency Division, CSIR-Indian Institute of Petroleum, Dehradun, 248005, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Diptarka Dasgupta
- Biochemistry and Biotechnology Area, Material Resource Efficiency Division, CSIR-Indian Institute of Petroleum, Dehradun, 248005, India.
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India.
| | - Anjan Ray
- Biochemistry and Biotechnology Area, Material Resource Efficiency Division, CSIR-Indian Institute of Petroleum, Dehradun, 248005, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Sunil K Suman
- Biochemistry and Biotechnology Area, Material Resource Efficiency Division, CSIR-Indian Institute of Petroleum, Dehradun, 248005, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India
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Song X, Sheng H, Zhou Y, Yu Y, He Y, Wang Z. Construction, expression, purification, characterization, and structural analysis of microbial transglutaminase variants. Biotechnol Appl Biochem 2022; 69:2486-2495. [PMID: 34894362 DOI: 10.1002/bab.2298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 11/30/2021] [Indexed: 12/27/2022]
Abstract
Microbial transglutaminase (MTG, EC 2.3.2.13) derived from Streptomyces mobaraensis is widely used in the food and pharmaceutical industry because of its ability to synthesize isopeptide bonds between the proteinogenic side chains of glutamine and lysine. The half-life (t1/2 ) of the activated wild-type enzyme at 60°C is 2 min. To improve the activity and thermostability of MTG for higher temperature application, three variants (Mut1, Mut2, and Mut3) were obtained by combining key amino acid mutations on the basis of previous research results. The best variant Mut2 with a specific combination of five of seven substitutions (S2P-S23V-Y24N-R215A-H289Y) shows a 10-fold increased half-life at 60°C (t1/2 = 27.6 min), and a 2.4-fold increased specific enzyme activity (39.3 U/mg). As measured by circular dichroism, the curve of Mut2 was basically the same as that of MTG-WT. The structural simulation of Mut2 shows that the overall structure is discoid with a crack, but the crack openings are wider than that of MTG-WT. Furthermore, structural analysis of Mut2 showed that there were seven hydrogen bonds and one π-anion interaction between Mut2 and its adjacent amino acids, and the number of hydrogen bonds was one more than that of MTG-WT (six hydrogen bonds).
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Affiliation(s)
- Xiaoping Song
- Department of Pharmacy, Anhui Medical College, Hefei, China.,Anhui Engineering Research Center of Recombinant Protein Pharmaceutical Biotechnology, School of Life Science, University of Science and Technology of China, Hefei, China
| | - Hefang Sheng
- Department of Pharmacy, Anhui Medical College, Hefei, China
| | - Yueqiao Zhou
- Department of Pharmacy, Anhui Medical College, Hefei, China
| | - Yin Yu
- Department of Pharmacy, Anhui Medical College, Hefei, China.,Anhui Engineering Research Center of Recombinant Protein Pharmaceutical Biotechnology, School of Life Science, University of Science and Technology of China, Hefei, China
| | - Yingjiao He
- Department of Pharmacy, Anhui Medical College, Hefei, China
| | - Zihan Wang
- Department of Pharmacy, Anhui Medical College, Hefei, China.,Anhui Engineering Research Center of Recombinant Protein Pharmaceutical Biotechnology, School of Life Science, University of Science and Technology of China, Hefei, China
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Hunt for α-amylase from metagenome and strategies to improve its thermostability: a systematic review. World J Microbiol Biotechnol 2022; 38:203. [PMID: 35999473 DOI: 10.1007/s11274-022-03396-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/18/2022] [Indexed: 10/15/2022]
Abstract
With the advent of green chemistry, the use of enzymes in industrial processes serves as an alternative to the conventional chemical catalysts. A high demand for sustainable processes for catalysis has brought a significant attention to hunt for novel enzymes. Among various hydrolases, the α-amylase has a gamut of biotechnological applications owing to its pivotal role in starch-hydrolysis. Industrial demand requires enzymes with thermostability and to ameliorate this crucial property, various methods such as protein engineering, directed evolution and enzyme immobilisation strategies are devised. Besides the traditional culture-dependent approach, metagenome from uncultured bacteria serves as a bountiful resource for novel genes/biocatalysts. Exploring the extreme-niches metagenome, advancements in protein engineering and biotechnology tools encourage the mining of novel α-amylase and its stable variants to tap its robust biotechnological and industrial potential. This review outlines α-amylase and its genetics, its catalytic domain architecture and mechanism of action, and various molecular methods to ameliorate its production. It aims to impart understanding on mechanisms involved in thermostability of α-amylase, cover strategies to screen novel genes from futile habitats and some molecular methods to ameliorate its properties.
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Silva-Salinas A, Rodríguez-Delgado M, Gómez-Treviño J, López-Chuken U, Olvera-Carranza C, Blanco-Gámez EA. Novel Thermotolerant Amylase from Bacillus licheniformis Strain LB04: Purification, Characterization and Agar-Agarose. Microorganisms 2021; 9:microorganisms9091857. [PMID: 34576752 PMCID: PMC8470300 DOI: 10.3390/microorganisms9091857] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 08/23/2021] [Accepted: 08/26/2021] [Indexed: 01/17/2023] Open
Abstract
This study analyzed the thermostability and effect of calcium ions on the enzymatic activity of α-amylase produced by Bacillus licheniformis strain LB04 isolated from Espinazo Hot springs in Nuevo Leon, Mexico. The enzyme was immobilized by entrapment on agar-agarose beads, with an entrapment yield of 19.9%. The identification of the bacteria was carried out using 16s rDNA sequencing. The enzyme was purified through ion exchange chromatography (IEX) in a DEAE-Sephadex column, revealing a protein with a molecular weight of ≈130 kDa. The enzyme was stable at pH 3.0 and heat stable up to 80 °C. However, the optimum conditions were reached at 65 °C and pH 3.0, with a specific activity of 1851.7 U mg−1 ± 1.3. The agar-agarose immobilized α-amylase had a hydrolytic activity nearly 25% higher when compared to the free enzyme. This study provides critical information for the understanding of the enzymatic profile of B. licheniformis strain LB04 and the potential application of the microorganisms at an industrial level, specifically in the food industry.
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Affiliation(s)
- Anaid Silva-Salinas
- Centro de Investigación en Biotecnología y Nanotecnología (CIByN), Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, Parquede Investigación e Innovación Tecnológica, Km. 10 Autopista al Aeropuerto Internacional Mariano Escobedo, Apodaca C.P. 66629, Nuevo León, Mexico; (A.S.-S.); (M.R.-D.); (U.L.-C.)
| | - Melissa Rodríguez-Delgado
- Centro de Investigación en Biotecnología y Nanotecnología (CIByN), Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, Parquede Investigación e Innovación Tecnológica, Km. 10 Autopista al Aeropuerto Internacional Mariano Escobedo, Apodaca C.P. 66629, Nuevo León, Mexico; (A.S.-S.); (M.R.-D.); (U.L.-C.)
| | - Jesús Gómez-Treviño
- Laboratorio de Biología Molecular, CELAES, Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza C.P. 66455, Nuevo León, Mexico;
| | - Ulrico López-Chuken
- Centro de Investigación en Biotecnología y Nanotecnología (CIByN), Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, Parquede Investigación e Innovación Tecnológica, Km. 10 Autopista al Aeropuerto Internacional Mariano Escobedo, Apodaca C.P. 66629, Nuevo León, Mexico; (A.S.-S.); (M.R.-D.); (U.L.-C.)
| | - Clarita Olvera-Carranza
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Chamilpa, Cuernavaca C.P. 62210, Morelos, Mexico;
| | - Edgar Allan Blanco-Gámez
- Centro de Investigación en Biotecnología y Nanotecnología (CIByN), Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, Parquede Investigación e Innovación Tecnológica, Km. 10 Autopista al Aeropuerto Internacional Mariano Escobedo, Apodaca C.P. 66629, Nuevo León, Mexico; (A.S.-S.); (M.R.-D.); (U.L.-C.)
- Correspondence:
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Lim SJ, Oslan SN. Native to designed: microbial -amylases for industrial applications. PeerJ 2021; 9:e11315. [PMID: 34046253 PMCID: PMC8139272 DOI: 10.7717/peerj.11315] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 03/30/2021] [Indexed: 12/31/2022] Open
Abstract
Background -amylases catalyze the endo-hydrolysis of -1,4-D-glycosidic bonds in starch into smaller moieties. While industrial processes are usually performed at harsh conditions, -amylases from mainly the bacteria, fungi and yeasts are preferred for their stabilities (thermal, pH and oxidative) and specificities (substrate and product). Microbial -amylases can be purified and characterized for industrial applications. While exploring novel enzymes with these properties in the nature is time-costly, the advancements in protein engineering techniques including rational design, directed evolution and others have privileged their modifications to exhibit industrially ideal traits. However, the commentary on the strategies and preferably mutated residues are lacking, hindering the design of new mutants especially for enhanced substrate specificity and oxidative stability. Thus, our review ensures wider accessibility of the previously reported experimental findings to facilitate the future engineering work. Survey methodology and objectives A traditional review approach was taken to focus on the engineering of microbial -amylases to enhance industrially favoured characteristics. The action mechanisms of - and -amylases were compared to avoid any bias in the research background. This review aimed to discuss the advances in modifying microbial -amylases via protein engineering to achieve longer half-life in high temperature, improved resistance (acidic, alkaline and oxidative) and enhanced specificities (substrate and product). Captivating results were discussed in depth, including the extended half-life at 100C, pH 3.5 and 10, 1.8 M hydrogen peroxide as well as enhanced substrate (65.3%) and product (42.4%) specificities. These shed light to the future microbial -amylase engineering in achieving paramount biochemical traits ameliorations to apt in the industries. Conclusions Microbial -amylases can be tailored for specific industrial applications through protein engineering (rational design and directed evolution). While the critical mutation points are dependent on respective enzymes, formation of disulfide bridge between cysteine residues after mutations is crucial for elevated thermostability. Amino acids conversion to basic residues was reported for enhanced acidic resistance while hydrophobic interaction resulted from mutated hydrophobic residues in carbohydrate-binding module or surface-binding sites is pivotal for improved substrate specificity. Substitution of oxidation-prone methionine residues with non-polar residues increases the enzyme oxidative stability. Hence, this review provides conceptual advances for the future microbial -amylases designs to exhibit industrially significant characteristics. However, more attention is needed to enhance substrate specificity and oxidative stability since they are least reported.
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Affiliation(s)
- Si Jie Lim
- Enzyme Technology Laboratory, VacBio 5, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Siti Nurbaya Oslan
- Enzyme Technology Laboratory, VacBio 5, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Enzyme and Microbial Technology (EMTech) Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
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Li S, Yang Q, Tang B. Improving the thermostability and acid resistance of Rhizopus oryzae α-amylase by using multiple sequence alignment based site-directed mutagenesis. Biotechnol Appl Biochem 2020; 67:677-684. [PMID: 32133700 DOI: 10.1002/bab.1907] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 02/25/2020] [Indexed: 12/14/2022]
Abstract
Higher thermostability or acid resistance for fungal α-amylase will help to improve the sugar-making process and cut down the production costs. Here, the thermostability or acid resistance of Rhizopus oryzae α-amylase (ROAmy) was significantly enhanced by site-directed evolution based on multiple sequence alignment (MSA) method. For instance, compared with the wild-type ROAmy, the optimum temperature of mutants G136D and A144Y was increased from 50 to 55 °C, whereas for mutants V174R and I276P, the optimum temperature was increased from 50 to 60 °C. The optimum pH of mutants G136D and A144Y shifted from 5.5 to 5.0, whereas for mutants V174R and T253E, the optimum pH changed from 5.5 to 4.5. The results showed that mutant V174R had a 2.52-fold increase in half-life at 55 °C, a 2.55-fold increase in half-life at pH 4.5, and a 1.61-fold increase in catalytic efficiency (kcat /Km ) on soluble starch. The three-dimensional model simulation revealed that changes of hydrophilicity, hydrogen bond, salt bridge, or rigidity observed in mutants might mainly account for the improvement of thermostability and acid resistance. The mutants with improved catalytic properties attained in this work may render an accessible and operable approach for directed evolution of fungal α-amylase aimed at interesting functions.
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Affiliation(s)
- Song Li
- School of Biological and Chemical Engineering, Anhui Polytechnic University, Central Beijing Road, Wuhu, China
| | - Qian Yang
- School of Biological and Chemical Engineering, Anhui Polytechnic University, Central Beijing Road, Wuhu, China
| | - Bin Tang
- School of Biological and Chemical Engineering, Anhui Polytechnic University, Central Beijing Road, Wuhu, China
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Torktaz I, Hemmat J, Karkhane AA, Rigi G, Rostami A, Khezri J, Behroozi R. Molecular Engineering of the Geobacillus stearothermophilus α-Amylase and Cel5E from Chlostridium thermocellim; In Silico Approach. IRANIAN JOURNAL OF BIOTECHNOLOGY 2019; 16:e1284. [PMID: 31457020 PMCID: PMC6697822 DOI: 10.15171/ijb.1284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 10/24/2017] [Accepted: 10/25/2017] [Indexed: 11/23/2022]
Abstract
Background Considering natural thermal stability, Geobacillus stearothermophilus amylase and Cel5E from Clostridium thermocellum are good candidates for industrial applications. To be compatible with the industrial applications, this enzyme should be stable in the high temperatures, so any improvement in their thermal stability is valuable. Objectives Using in silico approach and identifying point mutations in the structure amylase of G. stearothermophilus and Cel5E from C. termocellum we tried to increase thermal stability of the enzymes along with their catalytic activity to reach a new industrial amylase with higher thermostability and an improved function. Materials and Methods In this study we predicted the 3D structure of the enzymes, then simulated the molecular docking study using MolDock, PLANTS, and Lamarkian genetic algorithm as scoring functions for the docking and in silico engineering of the protein aiming to increase the thermal stability and catalytic activity. Results A series of thermal stability increasing point mutations were exerted around the active site of the enzyme, then by docking procedure, the binding affinity was measured and finally a list of mutations which theoretically improved the increased thermal stability as well as catalytic activity were proposed. Conclusions Based on the in silico results obtained the modified enzymes seems to be suitable candidates for considering in both laboratory and industrial scales.
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Affiliation(s)
- Ibrahim Torktaz
- National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.,Biotechnology Department. Iranian Research Organization for Science and Technology (IROST) Tehran-Iran
| | - Jafar Hemmat
- Biotechnology Department. Iranian Research Organization for Science and Technology (IROST) Tehran-Iran
| | | | - Garshasb Rigi
- Department of Genetics, Faculty of Basic Science, University of Shahrekord, Shahrekord, Iran
| | - Amin Rostami
- Department of Basic Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Jafar Khezri
- National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | - Reza Behroozi
- National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
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Yin H, Zhang L, Yang Z, Li S, Nie X, Wang Y, Yang C. Contribution of domain B to the catalytic properties of a Flavobacteriaceae α-amylase. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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