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Cai X, Shi X, Wang JY, Hu CH, Shen JD, Zhang B, Liu ZQ, Zheng YG. Enhancing the Thermal Stability and Enzyme Activity of Ketopantoate Hydroxymethyltransferase through Interface Modification Engineering. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:13186-13195. [PMID: 38814711 DOI: 10.1021/acs.jafc.3c09589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
Ketopantoate hydroxymethyltransferase (KPHMT) plays a pivotal role in d-pantothenic acid biosynthesis. Most KPHMTs are homodecamers with low thermal stability, posing challenges for protein engineering and limiting output enhancement. Previously, a high-enzyme activity KPHMT mutant (K25A/E189S) from Corynebacterium glutamicum was screened as mother strain (M0). Building upon this strain, our study focused on interface engineering modifications, employing a multifaceted approach including integrating folding-free energy calculation, B-factor analysis, and conserved site analysis. Preliminary screening led to the selection of five mutants in the interface─E106S, E98T, E98N, S247I, and S247D─showing improved thermal stability, culminating in the double-site mutant M8 (M0-E98N/S247D). M8 exhibited a T1/2 value of 288.79 min at 50 °C, showing a 3.29-fold increase compared to M0. Meanwhile, the Tm value of M8 was elevated from 53.2 to 59.6 °C. Investigations of structural and molecular dynamics simulations revealed alterations in surface electrostatic charge distribution and the formation of increased hydrogen bonds between subunits, contributing to enhanced thermal stability. This investigation corroborates the efficacy of interface engineering modifications in bolstering KPHMT stability while showing its potential for positively impacting industrial d-pantothenic acid synthesis.
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Affiliation(s)
- Xue Cai
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Xue Shi
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Jia-Ying Wang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Cheng-Hao Hu
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Ji-Dong Shen
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Bo Zhang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Zhi-Qiang Liu
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Yu-Guo Zheng
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, P. R. China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China
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You S, Zha Z, Li J, Zhang W, Bai Z, Hu Y, Wang X, Chen Y, Chen Z, Wang J, Luo H. Improvement of XYL10C_∆N catalytic performance through loop engineering for lignocellulosic biomass utilization in feed and fuel industries. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:195. [PMID: 34598723 PMCID: PMC8487158 DOI: 10.1186/s13068-021-02044-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 09/23/2021] [Indexed: 06/01/2023]
Abstract
BACKGROUND Xylanase, an important accessory enzyme that acts in synergy with cellulase, is widely used to degrade lignocellulosic biomass. Thermostable enzymes with good catalytic activity at lower temperatures have great potential for future applications in the feed and fuel industries, which have distinct demands; however, the potential of the enzymes is yet to be researched. RESULTS In this study, a structure-based semi-rational design strategy was applied to enhance the low-temperature catalytic performance of Bispora sp. MEY-1 XYL10C_∆N wild-type (WT). Screening and comparisons were performed for the WT and mutant strains. Compared to the WT, the mutant M53S/F54L/N207G exhibited higher specific activity (2.9-fold; 2090 vs. 710 U/mg) and catalytic efficiency (2.8-fold; 1530 vs. 550 mL/s mg) at 40 °C, and also showed higher thermostability (the melting temperature and temperature of 50% activity loss after 30 min treatment increased by 7.7 °C and 3.5 °C, respectively). Compared with the cellulase-only treatment, combined treatment with M53S/F54L/N207G and cellulase increased the reducing sugar contents from corn stalk, wheat bran, and corn cob by 1.6-, 1.2-, and 1.4-folds, with 1.9, 1.2, and 1.6 as the highest degrees of synergy, respectively. CONCLUSIONS This study provides useful insights into the underlying mechanism and methods of xylanase modification for industrial utilization. We identified loop2 as a key functional area affecting the low-temperature catalytic efficiency of GH10 xylanase. The thermostable mutant M53S/F54L/N207G was selected for the highest low-temperature catalytic efficiency and reducing sugar yield in synergy with cellulase in the degradation of different types of lignocellulosic biomass.
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Affiliation(s)
- Shuai You
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212018 People’s Republic of China
| | - Ziqian Zha
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
| | - Jing Li
- Department of Nephrology, Affiliated Hospital of Jiangsu University, Zhenjiang, 212001 People’s Republic of China
| | - Wenxin Zhang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
| | - Zhiyuan Bai
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
| | - Yanghao Hu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
| | - Xue Wang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
| | - Yiwen Chen
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
| | - Zhongli Chen
- Xinyuan Cocoon Silk Group Co., Ltd., Nantong, 226600 People’s Republic of China
| | - Jun Wang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212018 People’s Republic of China
| | - Huiying Luo
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081 People’s Republic of China
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Wang L, Cao K, Pedroso MM, Wu B, Gao Z, He B, Schenk G. Sequence- and structure-guided improvement of the catalytic performance of a GH11 family xylanase from Bacillus subtilis. J Biol Chem 2021; 297:101262. [PMID: 34600889 PMCID: PMC8546418 DOI: 10.1016/j.jbc.2021.101262] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/25/2021] [Accepted: 09/27/2021] [Indexed: 12/02/2022] Open
Abstract
Xylanases produce xylooligosaccharides from xylan and have thus attracted increasing attention for their usefulness in industrial applications. Previously, we demonstrated that the GH11 xylanase XynLC9 from Bacillus subtilis formed xylobiose and xylotriose as the major products with negligible production of xylose when digesting corncob-extracted xylan. Here, we aimed to improve the catalytic performance of XynLC9 via protein engineering. Based on the sequence and structural comparisons of XynLC9 with the xylanases Xyn2 from Trichoderma reesei and Xyn11A from Thermobifida fusca, we identified the N-terminal residues 5-YWQN-8 in XynLC9 as engineering hotspots and subjected this sequence to site saturation and iterative mutagenesis. The mutants W6F/Q7H and N8Y possessed a 2.6- and 1.8-fold higher catalytic activity than XynLC9, respectively, and both mutants were also more thermostable. Kinetic measurements suggested that W6F/Q7H and N8Y had lower substrate affinity, but a higher turnover rate (kcat), which resulted in increased catalytic efficiency than WT XynLC9. Furthermore, the W6F/Q7H mutant displayed a 160% increase in the yield of xylooligosaccharides from corncob-extracted xylan. Molecular dynamics simulations revealed that the W6F/Q7H and N8Y mutations led to an enlarged volume and surface area of the active site cleft, which provided more space for substrate entry and product release and thus accelerated the catalytic activity of the enzyme. The molecular evolution approach adopted in this study provides the design of a library of sequences that captures functional diversity in a limited number of protein variants.
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Affiliation(s)
- Lijuan Wang
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, Jiangsu, China
| | - Kun Cao
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, Jiangsu, China
| | - Marcelo Monteiro Pedroso
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Bin Wu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, Jiangsu, China.
| | - Zhen Gao
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, Jiangsu, China.
| | - Bingfang He
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, Jiangsu, China
| | - Gerhard Schenk
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Brisbane, Queensland, Australia
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Klaewkla M, Pichyangkura R, Chunsrivirot S. Computational Design of Oligosaccharide-Producing Levansucrase from Bacillus licheniformis RN-01 to Increase Its Stability at High Temperature. J Phys Chem B 2021; 125:5766-5774. [PMID: 34047564 DOI: 10.1021/acs.jpcb.1c02016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Levan-type fructooligosaccharides (LFOs) and levan can potentially be used as ingredients in prebiotics, skincare products, and antitumor agents. The Y246S mutant of Bacillus licheniformis RN-01 levansucrase (oligosaccharide-producing levansucrase, OPL) was reported to productively synthesize LFOs; however, OPL's thermostability is low at high temperatures. To enhance OPL structural stability, this study employed molecular dynamics (AMBER) to identify a highly flexible region, as measured by its average root-mean-square fluctuation (RMSF) value, on the OPL surface and computational protein design (Rosetta) to rigidify and increase favorable interactions to increase its structural stability. AMBER identified region nine (residues 277-317) as a highly flexible region that was selected for design because it has the highest number of residues and the second-highest average RMSF, and it is farthest from the active site. Rosetta designed 14 mutants with the best ΔΔG value in each position, where three mutants have better ΔG than OPL. To determine whether their flexibilities and stabilities are lower than those of OPL, all 14 designed mutants were simulated at high temperature (500 K), and we found that K296E, G309S, and A310W mutants were predicted to be more stable and could retain their native structures better than OPL. Our results suggest that enhanced structural stabilities of these mutants are caused by increased hydrogen bond strengths of the designed residues and their neighboring residues. This study designed K296E, G309S, and A310W mutants of OPL with high potential for stability improvement, and they could potentially be used for the effective production of LFOs.
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Affiliation(s)
- Methus Klaewkla
- Structural and Computational Biology Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
| | - Rath Pichyangkura
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
| | - Surasak Chunsrivirot
- Structural and Computational Biology Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.,Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
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Li G, Zhou X, Li Z, Liu Y, Liu D, Miao Y, Wan Q, Zhang R. Significantly improving the thermostability of a hyperthermophilic GH10 family xylanase XynAF1 by semi-rational design. Appl Microbiol Biotechnol 2021; 105:4561-4576. [PMID: 34014347 DOI: 10.1007/s00253-021-11340-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 04/16/2021] [Accepted: 05/09/2021] [Indexed: 11/28/2022]
Abstract
Xylanases have a broad range of applications in industrial biotechnologies, which require the enzymes to resist the high-temperature environments. The majority of xylanases have maximum activity at moderate temperatures, which limited their potential applications in industries. In this study, a thermophilic GH10 family xylanase XynAF1 from the high-temperature composting strain Aspergillus fumigatus Z5 was characterized and engineered to further improve its thermostability. XynAF1 has the optimal reaction temperature of 90 °C. The crystal structure of XynAF1 was obtained by X-ray diffraction after heterologous expression, purification, and crystallization. The high-resolution X-ray crystallographic structure of the protein-product complex was obtained by soaking the apo-state crystal with xylotetraose. Structure analysis indicated that XynAF1 has a rigid skeleton, which helps to maintain the hyperthermophilic characteristic. The homologous structure analysis and the catalytic center mutant construction of XynAF1 indicated the conserved catalytic center contributed to the high optimum catalytic temperature. The amino acids in the surface of xylanase XynAF1 which might influence the enzyme thermostability were identified by the structure analysis. Combining the rational design with the saturation mutation at the high B-value regions, the integrative mutant XynAF1-AC with a 6-fold increase of thermostability was finally obtained. This study efficiently improved the thermostability of a GH10 family xylanase by semi-rational design, which provided a new biocatalyst for high-temperature biotechnological applications. KEY POINTS: • Obtained the crystal structure of GH10 family hyperthermophilic xylanase XynAF1. • Shed light on the understanding of the GH10 family xylanase thermophilic mechanism. • Constructed a 6-fold increased thermostability recombinant xylanase.
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Affiliation(s)
- Guangqi Li
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China.,Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Xuan Zhou
- National Agricultural Technology Extension and Service Center, Beijing, 100125, People's Republic of China
| | - Zhihong Li
- College of Science, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yunpeng Liu
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Dongyang Liu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Youzhi Miao
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Qun Wan
- College of Science, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China. .,The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
| | - Ruifu Zhang
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China. .,Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
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6
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Yang J, Ma T, Shang-Guan F, Han Z. Improving the catalytic activity of thermostable xylanase from Thermotoga maritima via mutagenesis of non-catalytic residues at glycone subsites. Enzyme Microb Technol 2020; 139:109579. [PMID: 32732029 DOI: 10.1016/j.enzmictec.2020.109579] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/31/2020] [Accepted: 04/14/2020] [Indexed: 10/24/2022]
Abstract
Endo-β-1,4-xylanase from Thermotoga maritima, TmxB, is an industrially attractive enzyme due to its extreme thermostability. To improve its application value, four variants were designed on the basis of multiple sequence and three-dimensional structure alignments. Wild-type TmxB (wt-TmxB) and its mutants were produced via a Pichia pastoris expression system. Among four single-site mutants, the tyrosine substitution of a threonine residue (T74Y) at putative -3/-4 subsite led to a 1.3-fold increase in specific activity at 40 °C - 100 °C and pH 5 for 5 min, with beechwood xylan as the substrate. T74Y had an improved catalytic efficiency (kcat/Km), being 1.6 times that of wt-TmxB. Variants DY (two amino acid insertions) and N68Q displayed a slight increase (1.2 fold) and dramatic decline (1.7 fold) in catalytic efficiency, respectively. Mutant E67Y was totally inactive under all test conditions. Structural modeling and docking simulation elucidated structural insights into the molecular mechanism of activity changes for these TmxB variants. This study helps in further understanding the roles of the non-catalytic amino acids at the glycone subsites of xylanases from glycoside hydrolase family 10.
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Affiliation(s)
- Jiangke Yang
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Tengfei Ma
- School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Fang Shang-Guan
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Zhenggang Han
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China.
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Sun Z, Liu Q, Qu G, Feng Y, Reetz MT. Utility of B-Factors in Protein Science: Interpreting Rigidity, Flexibility, and Internal Motion and Engineering Thermostability. Chem Rev 2019; 119:1626-1665. [PMID: 30698416 DOI: 10.1021/acs.chemrev.8b00290] [Citation(s) in RCA: 280] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Zhoutong Sun
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Qian Liu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ge Qu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Yan Feng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Manfred T. Reetz
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Chemistry Department, Philipps-University, Hans-Meerwein-Strasse 4, 35032 Marburg, Germany
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Trabelsi S, Sahnoun M, Elgharbi F, Ameri R, Ben Mabrouk S, Mezghani M, Hmida-Sayari A, Bejar S. Aspergillus oryzae S2 AmyA amylase expression in Pichia pastoris: production, purification and novel properties. Mol Biol Rep 2018; 46:921-932. [PMID: 30535895 DOI: 10.1007/s11033-018-4548-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 11/30/2018] [Indexed: 01/05/2023]
Abstract
A synthetic cDNA-AmyA gene was cloned and successfully expressed in Pichia pastoris as a His-tagged enzyme under the methanol inducible AOX1 promoter. High level of extracellular amylase production of 72 U/mL was obtained after a 72 h induction by methanol. As expected, the recombinant strain produced only the AmyA isoform since the host is a protease deficient strain. Besides, the purified r-AmyA showed a molecular mass of 54 kDa, the same pH optimum equal to 5.6 but a higher thermoactivity of 60 °C against 50 °C for the native enzyme. Unlike AmyA which maintained 50% of its activity after a 10-min incubation at 60 °C, r-AmyA reached 45 min. The higher thermoactivity and thermostability could be related to the N-glycosylation. The r-AmyA activity was enhanced by 46% and 45% respectively in the presence of 4 mM Fe2+ and Mg2+ ions. This enzyme was more efficient in bread-making since such ions were reported to have a positive impact on the nutriment quality and the rheological characteristics of the wheat flour dough. The thermoactivity/thermostability as well as the iron and magnesium activations could also be ascribed to the presence of an additional C-terminal loop containing the His tag.
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Affiliation(s)
- Sahar Trabelsi
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia
| | - Mouna Sahnoun
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia
| | - Fatma Elgharbi
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia
| | - Rihab Ameri
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia
| | - Sameh Ben Mabrouk
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia
| | - Monia Mezghani
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia
| | - Aïda Hmida-Sayari
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia
| | - Samir Bejar
- Laboratory of Microbial Biotechnology and Engineering Enzymes (LMBEE), Centre of Biotechnology of Sfax (CBS), University of Sfax, Sidi Mansour Road Km 6, P.O. Box 1177, 3018, Sfax, Tunisia.
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Li A, Sun Z, Reetz MT. Solid-Phase Gene Synthesis for Mutant Library Construction: The Future of Directed Evolution? Chembiochem 2018; 19:2023-2032. [PMID: 30044530 DOI: 10.1002/cbic.201800339] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Indexed: 11/05/2022]
Affiliation(s)
- Aitao Li
- Hubei Collaborative Innovation Center for Green Transformation of, Bio-resources; Hubei Key Laboratory of Industrial Biotechnology; College of Life Sciences; Hubei University; 368 Youyi Road Wuchang Wuhan 430062 China
| | - Zhoutong Sun
- Tianjin Institute of Industrial Biotechnology; Chinese Academy of Sciences; 32 West 7th Avenue Tianjin Airport Economic Area Tianjin 300308 China
| | - Manfred T. Reetz
- Max-Planck-Institut für Kohlenforschung; Kaiser-Wilhelm-Platz 1 45470 Mülheim Germany
- Tianjin Institute of Industrial Biotechnology; Chinese Academy of Sciences; 32 West 7th Avenue Tianjin Airport Economic Area Tianjin 300308 China
- Department of Chemistry; Philipps University; Hans-Meerwein-Strasse 4 35032 Marburg Germany
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Basit A, Liu J, Rahim K, Jiang W, Lou H. Thermophilic xylanases: from bench to bottle. Crit Rev Biotechnol 2018; 38:989-1002. [DOI: 10.1080/07388551.2018.1425662] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Abdul Basit
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Junquan Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Kashif Rahim
- Beijing Key Laboratory of Genetic Engineering Drug and Biotechnology, Institute of Biochemistry and Biotechnology, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Wei Jiang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Huiqiang Lou
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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