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Cui X, Yuan X, Li S, Hu X, Zhao J, Zhang G. Simultaneously improving the specific activity and thermostability of α-amylase BLA by rational design. Bioprocess Biosyst Eng 2022; 45:1839-1848. [PMID: 36136173 DOI: 10.1007/s00449-022-02790-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 09/10/2022] [Indexed: 11/02/2022]
Abstract
Higher activity and alkaline α-amylases are desired for textile desizing and detergent additive. Here, rational design was used to improve the specific activity and thermostability of the α-amylase BLA from Bacillus licheniformis. Seventeen mutants of BLA were designed based on sequence consensus analysis and folding free energy calculation, and characterized by measuring their respective activity and thermostability at pH 8.5. Among them, mutant Q360C exhibited nearly threefold improved activity than that of wild-type and retained a higher residual activity (75% vs 59% for wild-type) after preincubation at 70 ℃ for 30 min. The modeled structures and molecular dynamics simulations analysis demonstrated that the enhanced hydrophobic interaction near residue 360 and reduced disturbance to the conformation of catalytic residues are the possible reasons for the improved thermostability and activity of Q360C. The results suggest that 360th of BLA may act as a hotspot for engineering other enzymes in the GH13 superfamily.
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Affiliation(s)
- Xin Cui
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.,State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China
| | - Xin Yuan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China
| | - Shunyi Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China
| | - Xinlin Hu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China
| | - Jing Zhao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China.
| | - Guimin Zhang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China. .,State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China.
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2
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Su C, Gong JS, Qin A, Li H, Li H, Qin J, Qian JY, Xu ZH, Shi JS. A combination of bioinformatics analysis and rational design strategies to enhance keratinase thermostability for efficient biodegradation of feathers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 818:151824. [PMID: 34808176 DOI: 10.1016/j.scitotenv.2021.151824] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 11/06/2021] [Accepted: 11/16/2021] [Indexed: 06/13/2023]
Abstract
Keratinase has shown great significance and application potentials in the biodegradation and recycle of keratin waste due to its unique and efficient hydrolysis ability. However, the inherent instability of the enzyme limits its practical utilization. Herein, we obtained a thermostability-enhanced keratinase based on a combination of bioinformatics analysis and rational design strategies for the efficient biodegradation of feathers. A systematical in silico analysis combined with filtering of virtual libraries derived a smart library for experimental validation. Synergistic mutations around the highly flexible loop, the calcium binding site and the non-consensus amino acids generated a dominant mutant which increased the optimal temperature of keratinase from 40 °C to 60 °C, and the half-life at 60 °C was increased from 17.3 min to 66.1 min. The mutant could achieve more than 66% biodegradation of 50 g/L feathers to high-valued keratin product with a major molecular weight of 36 kDa. Collectively, this work provided a promising keratinase variant with enhanced thermostability for efficient conversion of keratin wastes to valuable products. It also generated a general strategy to facilitate enzyme thermostability design which is more targeted and predictable.
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Affiliation(s)
- Chang Su
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China.
| | - Anqi Qin
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Heng Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Hui Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Jiufu Qin
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, PR China
| | - Jian-Ying Qian
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Zheng-Hong Xu
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China; Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China.
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3
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Saad WF, Othman AM, Abdel-Fattah M, Ahmad MS. Response surface methodology as an approach for optimization of α-amylase production by the new isolated thermotolerant Bacillus licheniformis WF67 strain in submerged fermentation. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.101944] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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4
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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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5
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Pinto ÉSM, Dorn M, Feltes BC. The tale of a versatile enzyme: Alpha-amylase evolution, structure, and potential biotechnological applications for the bioremediation of n-alkanes. CHEMOSPHERE 2020; 250:126202. [PMID: 32092569 DOI: 10.1016/j.chemosphere.2020.126202] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 01/10/2020] [Accepted: 02/12/2020] [Indexed: 06/10/2023]
Abstract
As the primary source of a wide range of industrial products, the study of petroleum-derived compounds is of pivotal importance. However, the process of oil extraction and refinement is among the most environmentally hazardous practices, impacting almost all levels of the ecological chain. So far, the most appropriate strategy to overcome such an issue is through bioremediation, which revolves around the employment of different microorganisms to degrade hazardous compounds, generating less environmental impact and lower monetary costs. In this sense, a myriad of organisms and enzymes are considered possible candidates for the bioremediation process. Amidst the potential candidates is α-amylase, an evolutionary conserved starch-degrading enzyme. Notably, α-amylase was not only seen to degrade n-alkanes, a subclass of alkanes considered the most abundant petroleum-derived compounds but also low-density polyethylene, a dangerous pollutant produced from petroleum. Thus, due to its high conservation in both eukaryotic and prokaryotic lineages, in addition to the capability to degrade different types of hazardous compounds, the study of α-amylase becomes a rising interest. Nevertheless, there are no studies that review all biotechnological applications of α-amylase for bioremediation. In this work, we critically review the potential biotechnological applications of α-amylase, focusing on the biodegradation of petroleum-derived compounds. Evolutionary aspects are discussed, as well for all structural information and all features that could impact on the employment of this protein in the biotechnological industry, such as pH, temperature, and medium conditions. New perspectives and critical assessments are conducted regarding the application of α-amylase in the bioremediation of n-alkanes.
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Affiliation(s)
- Éderson Sales Moreira Pinto
- Laboratory of Structural Bioinformatics and Computational Biology, Center for Biotechnology, Federal University of Rio Grande do Sul, Brazil
| | - Márcio Dorn
- Laboratory of Structural Bioinformatics and Computational Biology, Institute of Informatics, Federal University of Rio Grande do Sul, Brazil; Laboratory of Structural Bioinformatics and Computational Biology, Center for Biotechnology, Federal University of Rio Grande do Sul, Brazil
| | - Bruno César Feltes
- Laboratory of Structural Bioinformatics and Computational Biology, Institute of Informatics, Federal University of Rio Grande do Sul, Brazil.
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Expression of Bacillus licheniformis α-amylase in Pichia pastoris without antibiotics-resistant gene and effects of glycosylation on the enzymic thermostability. 3 Biotech 2019; 9:427. [PMID: 31696032 DOI: 10.1007/s13205-019-1943-x] [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: 03/22/2019] [Accepted: 10/10/2019] [Indexed: 10/25/2022] Open
Abstract
Thermostable α-amylases are widely used in industry. The α-amylase from Bacillus licheniformis (BLA) with six potential glycosylation sites possessed excellent thermal and pH stability and high activity. Here, it was expressed in Pichia pastoris. The Pic-BLA-producing yeast without any antibiotics-resistant gene was cultivated in flasks and the amylase activity in fermentation supernatant reached 900 U/mL. The recombinant α-amylase Pic-BLA produced in P. pastoris was deeply glycosylated with 30% increase in molecular mass (MM). The deglycosylation treatment by Endoglycosidase H (Endo H) reduced the MM of Pic-BLA. Thermostability analysis showed that Pic-BLA and deglycosylated Pic-BLA were similar in heat tolerance. In order to eliminate the extra impact of Endo H, the BLA was also expressed in Escherichia coli to get non-glycosylated Eco-BLA. A comparative study between non-glycosylated Eco-BLA and glycosylated Pic-BLA showed no obvious difference in thermostability. It is speculated that the glycosylation has little effect on the thermostability of α-amylase BLA.
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7
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Enhanced acidic adaptation of Bacillus subtilis Ca-independent alpha-amylase by rational engineering of pKa values. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2018.08.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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8
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Wu H, Tian X, Dong Z, Zhang Y, Huang L, Liu X, Jin P, Lu F, Wang Z. Engineering of Bacillus amyloliquefaciens
α-Amylase with Improved Calcium Independence and Catalytic Efficiency by Error-Prone PCR. STARCH-STARKE 2017. [DOI: 10.1002/star.201700175] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Haiyang Wu
- H. Wu, X. Tian, Dr. Z. Dong, Prof. X. Liu, Dr. P. Jin, Prof. Z. Wang; Department of Biological Chemical Engineering; College of Chemical Engineering and Materials Science; Tianjin University of Science and Technology; Tianjin 300457 China
- H. Wu, X. Tian, Y. Zhang, L. Huang, Prof. F. Lu, Prof. Z. Wang; College of Biotechnology; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Xiaojing Tian
- H. Wu, X. Tian, Dr. Z. Dong, Prof. X. Liu, Dr. P. Jin, Prof. Z. Wang; Department of Biological Chemical Engineering; College of Chemical Engineering and Materials Science; Tianjin University of Science and Technology; Tianjin 300457 China
- H. Wu, X. Tian, Y. Zhang, L. Huang, Prof. F. Lu, Prof. Z. Wang; College of Biotechnology; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Zixing Dong
- H. Wu, X. Tian, Dr. Z. Dong, Prof. X. Liu, Dr. P. Jin, Prof. Z. Wang; Department of Biological Chemical Engineering; College of Chemical Engineering and Materials Science; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Yongjie Zhang
- H. Wu, X. Tian, Y. Zhang, L. Huang, Prof. F. Lu, Prof. Z. Wang; College of Biotechnology; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Lei Huang
- H. Wu, X. Tian, Y. Zhang, L. Huang, Prof. F. Lu, Prof. Z. Wang; College of Biotechnology; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Xiaoguang Liu
- H. Wu, X. Tian, Dr. Z. Dong, Prof. X. Liu, Dr. P. Jin, Prof. Z. Wang; Department of Biological Chemical Engineering; College of Chemical Engineering and Materials Science; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Peng Jin
- H. Wu, X. Tian, Dr. Z. Dong, Prof. X. Liu, Dr. P. Jin, Prof. Z. Wang; Department of Biological Chemical Engineering; College of Chemical Engineering and Materials Science; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Fuping Lu
- H. Wu, X. Tian, Y. Zhang, L. Huang, Prof. F. Lu, Prof. Z. Wang; College of Biotechnology; Tianjin University of Science and Technology; Tianjin 300457 China
| | - Zhengxiang Wang
- H. Wu, X. Tian, Dr. Z. Dong, Prof. X. Liu, Dr. P. Jin, Prof. Z. Wang; Department of Biological Chemical Engineering; College of Chemical Engineering and Materials Science; Tianjin University of Science and Technology; Tianjin 300457 China
- H. Wu, X. Tian, Y. Zhang, L. Huang, Prof. F. Lu, Prof. Z. Wang; College of Biotechnology; Tianjin University of Science and Technology; Tianjin 300457 China
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9
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Functional characterization and crystal structure of thermostable amylase from Thermotoga petrophila , reveals high thermostability and an unusual form of dimerization. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017. [DOI: 10.1016/j.bbapap.2017.06.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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10
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Crystal structure of a raw-starch-degrading bacterial α-amylase belonging to subfamily 37 of the glycoside hydrolase family GH13. Sci Rep 2017; 7:44067. [PMID: 28303907 PMCID: PMC5355875 DOI: 10.1038/srep44067] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 02/02/2017] [Indexed: 01/14/2023] Open
Abstract
Subfamily 37 of the glycoside hydrolase family GH13 was recently established on the basis of the discovery of a novel α-amylase, designated AmyP, from a marine metagenomic library. AmyP exhibits raw-starch-degrading activity and consists of an N-terminal catalytic domain and a C-terminal starch-binding domain. To understand this newest subfamily, we determined the crystal structure of the catalytic domain of AmyP, named AmyPΔSBD, complexed with maltose, and the crystal structure of the E221Q mutant AmyPΔSBD complexed with maltotriose. Glu221 is one of the three conserved catalytic residues, and AmyP is inactivated by the E221Q mutation. Domain B of AmyPΔSBD forms a loop that protrudes from domain A, stabilizes the conformation of the active site and increases the thermostability of the enzyme. A new calcium ion is situated adjacent to the -3 subsite binding loop and may be responsible for the increased thermostability of the enzyme after the addition of calcium. Moreover, Tyr36 participates in both stacking and hydrogen bonding interactions with the sugar motif at subsite -3. This work provides the first insights into the structure of α-amylases belonging to subfamily 37 of GH13 and may contribute to the rational design of α-amylase mutants with enhanced performance in biotechnological applications.
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11
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Gao Y, Huang M, Sun X, Zhang X, Zhang Y, Zhou X, Cai M. Single-site mutation of C363G or N463T strengthens thermostability improvement of IG181–182 deleted acidic α-amylase from deep-sea thermophile Geobacillus sp. FOOD BIOTECHNOL 2017. [DOI: 10.1080/08905436.2016.1276462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Yanyun Gao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Mengmeng Huang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Xiaoyue Sun
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Xiaoxu Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Yuanxing Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
- Shanghai Collaborative Innovation Center for Biomanufacturing, Shanghai, China
| | - Xiangshan Zhou
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Menghao Cai
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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12
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Chai KP, Othman NFB, Teh AH, Ho KL, Chan KG, Shamsir MS, Goh KM, Ng CL. Crystal structure of Anoxybacillus α-amylase provides insights into maltose binding of a new glycosyl hydrolase subclass. Sci Rep 2016; 6:23126. [PMID: 26975884 PMCID: PMC4791539 DOI: 10.1038/srep23126] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 02/17/2016] [Indexed: 11/18/2022] Open
Abstract
A new subfamily of glycosyl hydrolase family GH13 was recently proposed for α-amylases from Anoxybacillus species (ASKA and ADTA), Geobacillus thermoleovorans (GTA, Pizzo, and GtamyII), Bacillus aquimaris (BaqA), and 95 other putative protein homologues. To understand this new GH13 subfamily, we report crystal structures of truncated ASKA (TASKA). ASKA is a thermostable enzyme capable of producing high levels of maltose. Unlike GTA, biochemical analysis showed that Ca2+ ion supplementation enhances the catalytic activities of ASKA and TASKA. The crystal structures reveal the presence of four Ca2+ ion binding sites, with three of these binding sites are highly conserved among Anoxybacillus α-amylases. This work provides structural insights into this new GH13 subfamily both in the apo form and in complex with maltose. Furthermore, structural comparison of TASKA and GTA provides an overview of the conformational changes accompanying maltose binding at each subsite.
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Affiliation(s)
- Kian Piaw Chai
- Universiti Teknologi Malaysia, Faculty of Biosciences and Medical Engineering, 81310 Skudai, Johor, Malaysia
| | - Noor Farhan Binti Othman
- Universiti Kebangsaan Malaysia, Institute of Systems Biology, 43600 UKM Bangi, Selangor, Malaysia
| | - Aik-Hong Teh
- Universiti Sains Malaysia, Centre for Chemical Biology, 11800 Penang, Malaysia
| | - Kok Lian Ho
- Universiti Putra Malaysia, Department of Pathology, Faculty of Medicine and Health Sciences, 43400 Serdang, Selangor, Malaysia
| | - Kok-Gan Chan
- University of Malaya, Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, 50603 Kuala Lumpur, Malaysia
| | - Mohd Shahir Shamsir
- Universiti Teknologi Malaysia, Faculty of Biosciences and Medical Engineering, 81310 Skudai, Johor, Malaysia
| | - Kian Mau Goh
- Universiti Teknologi Malaysia, Faculty of Biosciences and Medical Engineering, 81310 Skudai, Johor, Malaysia
| | - Chyan Leong Ng
- Universiti Kebangsaan Malaysia, Institute of Systems Biology, 43600 UKM Bangi, Selangor, Malaysia
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13
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Ranjani V, Janeček Š, Chai KP, Shahir S, Rahman RNZRA, Chan KG, Goh KM. Protein engineering of selected residues from conserved sequence regions of a novel Anoxybacillus α-amylase. Sci Rep 2014; 4:5850. [PMID: 25069018 PMCID: PMC5376179 DOI: 10.1038/srep05850] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 07/08/2014] [Indexed: 11/08/2022] Open
Abstract
The α-amylases from Anoxybacillus species (ASKA and ADTA), Bacillus aquimaris (BaqA) and Geobacillus thermoleovorans (GTA, Pizzo and GtamyII) were proposed as a novel group of the α-amylase family GH13. An ASKA yielding a high percentage of maltose upon its reaction on starch was chosen as a model to study the residues responsible for the biochemical properties. Four residues from conserved sequence regions (CSRs) were thus selected, and the mutants F113V (CSR-I), Y187F and L189I (CSR-II) and A161D (CSR-V) were characterised. Few changes in the optimum reaction temperature and pH were observed for all mutants. Whereas the Y187F (t1/2 43 h) and L189I (t1/2 36 h) mutants had a lower thermostability at 65°C than the native ASKA (t1/2 48 h), the mutants F113V and A161D exhibited an improved t1/2 of 51 h and 53 h, respectively. Among the mutants, only the A161D had a specific activity, k(cat) and k(cat)/K(m) higher (1.23-, 1.17- and 2.88-times, respectively) than the values determined for the ASKA. The replacement of the Ala-161 in the CSR-V with an aspartic acid also caused a significant reduction in the ratio of maltose formed. This finding suggests the Ala-161 may contribute to the high maltose production of the ASKA.
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Affiliation(s)
- Velayudhan Ranjani
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, 81310 Johor, Malaysia
| | - Štefan Janeček
- Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, SK-84551 Bratislava, Slovakia
- Department of Biology, Faculty of Natural Sciences, University of SS. Cyril and Methodius, SK-91701 Trnava, Slovakia
| | - Kian Piaw Chai
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, 81310 Johor, Malaysia
| | - Shafinaz Shahir
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, 81310 Johor, Malaysia
| | - Raja Noor Zaliha Raja Abdul Rahman
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Kok-Gan Chan
- Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kian Mau Goh
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, 81310 Johor, Malaysia
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14
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Li C, Ban X, Gu Z, Li Z. Calcium ion contribution to thermostability of cyclodextrin glycosyltransferase is closely related to calcium-binding site CaIII. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:8836-8841. [PMID: 23968201 DOI: 10.1021/jf4024273] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In the study, we investigated the contribution of Ca²⁺ to the thermostability of α-cyclodextrin glycosyltransferase (α-CGTase) from Paenibacillus macerans , which has two calcium-binding sites (CaI and CaII), and β-CGTase from Bacillus circulans , which contains an additional calcium-binding site (CaIII), consisting of Ala315 and Asp577. It was found that the contribution of Ca²⁺ to the thermostability of two CGTases displayed a marked difference. Ca²⁺ affected β-CGTase thermostability significantly. After Ca²⁺ was added to β-CGTase solution to a final concentration of 5 mM followed by incubation for 120 min at 60 °C, residual activity of β-CGTase was 88.3%, which was much higher than that without Ca²⁺. However, Ca²⁺ had a small contribution to α-CGTase thermostability. Furthermore, A315D and D577K mutations at CaIII could significantly change the contribution of Ca²⁺ to β-CGTase thermostability. These results suggested that the contribution of Ca²⁺ to CGTase thermostability was closely related to CaIII.
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Affiliation(s)
- Caiming Li
- State Key Laboratory of Food Science and Technology, and ‡School of Food Science and Technology, Jiangnan University , Wuxi 214122, People's Republic of China
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15
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Sharma A, Satyanarayana T. Microbial acid-stable α-amylases: Characteristics, genetic engineering and applications. Process Biochem 2013. [DOI: 10.1016/j.procbio.2012.12.018] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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16
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Goh PH, Illias RM, Goh KM. Rational mutagenesis of cyclodextrin glucanotransferase at the calcium binding regions for enhancement of thermostability. Int J Mol Sci 2012; 13:5307-5323. [PMID: 22754298 PMCID: PMC3382795 DOI: 10.3390/ijms13055307] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 03/08/2012] [Accepted: 04/13/2012] [Indexed: 11/16/2022] Open
Abstract
Studies related to the engineering of calcium binding sites of CGTase are limited. The calcium binding regions that are known for thermostability function were subjected to site-directed mutagenesis in this study. The starting gene-protein is a variant of CGTase Bacillus sp. G1, reported earlier and denoted as “parent CGTase” herein. Four CGTase variants (S182G, S182E, N132R and N28R) were constructed. The two variants with a mutation at residue 182, located adjacent to the Ca-I site and the active site cleft, possessed an enhanced thermostability characteristic. The activity half-life of variant S182G at 60 °C was increased to 94 min, while the parent CGTase was only 22 min. This improvement may be attributed to the formation of a shorter α-helix and the alleviation of unfavorable steric strains by glycine at the corresponding region. For the variant S182E, an extra ionic interaction at the A/B domain interface increased the half-life to 31 min, yet it reduced CGTase activity. The introduction of an ionic interaction at the Ca-I site via the mutation N132R disrupted CGTase catalytic activity. Conversely, the variant N28R, which has an additional ionic interaction at the Ca-II site, displayed increased cyclization activity. However, thermostability was not affected.
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Affiliation(s)
| | | | - Kian Mau Goh
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +607-5534346; Fax: +607-5531112
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17
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Significance of Tyr302, His235 and Asp194 in the α-amylase from Bacillus licheniformis. Biotechnol Lett 2012; 34:895-9. [DOI: 10.1007/s10529-011-0843-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 12/22/2011] [Indexed: 10/14/2022]
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18
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Mutational analysis of the proposed calcium-binding aspartates of a truncated α-amylase from Bacillus sp. strain TS-23. ANN MICROBIOL 2010. [DOI: 10.1007/s13213-010-0042-3] [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] Open
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19
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Liu Y, Shen W, Shi GY, Wang ZX. Role of the calcium-binding residues Asp231, Asp233, and Asp438 in alpha-amylase of Bacillus amyloliquefaciens as revealed by mutational analysis. Curr Microbiol 2009; 60:162-6. [PMID: 19841977 DOI: 10.1007/s00284-009-9517-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Accepted: 09/24/2009] [Indexed: 11/26/2022]
Abstract
Role of the calcium-binding residues Asp231, Asp233, and Asp438 of Bacillus amyloliquefaciens alpha-amylase (BAA) on the enzyme properties was investigated by site-directed mutagenesis. The calcium-binding residues Asp231, Asp233, and Asp438 were replaced with Asn, Asn, and Gly to produce the mutants D231N, D233N, and D438G, respectively. The mutant amylases were purified to homogeneity and the purified enzymes was estimated to be approximately 58 kDa. The specific activity for the mutant enzyme D233N was decreased by 84.8%, while D231N and D438G showed a decrease of 6.3% and 3.5% to that of the wild-type enzyme, respectively. No significant changes in the K (m) value, thermo-stability, optimum temperature, and optimum pH were observed in the mutations of D231N and D438G, while substitution of Asp233 with Asn resulted in a dramatic reduction in the value of catalytic efficiency (K (cat)/K (m)) and thermo-stability at 60 degrees C. The ranges of optimum temperature and optimum pH for D233N were also reduced to about 10 degrees C and 3-4 units, respectively.
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Affiliation(s)
- Yang Liu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.
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20
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Shankar M, Priyadharshini R, Gunasekaran P. Quantitative digital image analysis of chromogenic assays for high throughput screening of α-amylase mutant libraries. Biotechnol Lett 2009; 31:1197-201. [DOI: 10.1007/s10529-009-9999-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Revised: 03/23/2009] [Accepted: 03/23/2009] [Indexed: 11/28/2022]
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