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Gufe C, Jambwa P, Marumure J, Makuvara Z, Khunrae P, Kayoka-Kabongo PN. Are phenolic compounds produced during the enzymatic production of prebiotic xylooligosaccharides (XOS) beneficial: a review. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2024:1-16. [PMID: 38594834 DOI: 10.1080/10286020.2024.2328723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 03/05/2024] [Indexed: 04/11/2024]
Abstract
Phenolics produced during xylooligosaccharide production might inhibit xylanases and enhance the antioxidant and antimicrobial activities of XOS. The effects of phenolic compounds on xylanases may depend on the type and concentration of the compound, the plant biomass used, and the enzyme used. Understanding the effects of phenolic compounds on xylanases and their impact on XOS is critical for developing viable bioconversion of lignocellulosic biomass to XOS. Understanding the complex relationship between phenolic compounds and xylanases can lead to the development of strategies that improve the efficiency and cost-effectiveness of XOS manufacturing processes and optimise enzyme performance.
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Affiliation(s)
- Claudious Gufe
- Department of Veterinary Technical Services, Central Veterinary Laboratories, Borrowdale Road, Harare, Zimbabwe
| | - Prosper Jambwa
- Department of Veterinary Biosciences, Faculty of Veterinary Science, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe
| | - Jerikias Marumure
- School of Natural Sciences, Great Zimbabwe University, Masvingo, Zimbabwe
| | - Zakio Makuvara
- School of Natural Sciences, Great Zimbabwe University, Masvingo, Zimbabwe
| | - Pongsak Khunrae
- Department of Microbiology, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bang Mod, Thung Khru, Bangkok, Thailand
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Li Y, Song W, Han X, Wang Y, Rao S, Zhang Q, Zhou J, Li J, Liu S, Du G. Recent progress in key lignocellulosic enzymes: Enzyme discovery, molecular modifications, production, and enzymatic biomass saccharification. BIORESOURCE TECHNOLOGY 2022; 363:127986. [PMID: 36126851 DOI: 10.1016/j.biortech.2022.127986] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 05/15/2023]
Abstract
Lignocellulose, the most prevalent biomass on earth, can be enzymatically converted into carbohydrates for bioethanol production and other uses. Among lignocellulosic enzymes, endoglucanase, xylanase, and laccase are the key enzymes, owing to their ability to disrupt the main structure of lignocellulose. Recently, new discovery methods have been established to obtain key lignocellulosic enzymes with excellent enzymatic properties. Molecular modification of enzymes to modulate their thermostability, catalytic activity, and substrate specificity has been performed with protein engineering technology. In addition, the enzyme expression has been effectively improved through expression element screening and host modification, as well as fermentation optimization. Immobilization of enzymes, use of surfactants, synergistic degradation, and optimization of reaction conditions have addressed the inefficiency of enzymatic saccharification. In this review, recent advances in key lignocellulosic enzymes are summarized, along with future prospects for the development of super-engineered strains and integrative technologies for enzymatic biomass saccharification.
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Affiliation(s)
- Yangyang Li
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Weiyan Song
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Xuyue Han
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Yachan Wang
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Shengqi Rao
- College of Food Science and Engineering, Yangzhou University, Yangzhou 214122, China
| | - Quan Zhang
- Dalian Research Institute of Petroleum and Petrochemicals, SINOPEC, Dalian 116000, China
| | - Jingwen Zhou
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Jianghua Li
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Song Liu
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China.
| | - Guocheng Du
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China; School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
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Kong J, Miao L, Lu Z, Wang S, Zhao B, Zhang C, Xiao D, Teo D, Leong SSJ, Wong A, Yu A. Enhanced production of amyrin in Yarrowia lipolytica using a combinatorial protein and metabolic engineering approach. Microb Cell Fact 2022; 21:186. [PMID: 36085205 PMCID: PMC9463779 DOI: 10.1186/s12934-022-01915-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 08/26/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Amyrin is an important triterpenoid and precursor to a wide range of cosmetic, pharmaceutical and nutraceutical products. In this study, we metabolically engineered the oleaginous yeast, Yarrowia lipolytica to produce α- and β-amyrin on simple sugar and waste cooking oil. RESULTS We first validated the in vivo enzymatic activity of a multi-functional amyrin synthase (CrMAS) from Catharanthus roseus, by expressing its codon-optimized gene in Y. lipolytica and assayed for amyrins. To increase yield, prevailing genes in the mevalonate pathway, namely HMG1, ERG20, ERG9 and ERG1, were overexpressed singly and in combination to direct flux towards amyrin biosynthesis. By means of a semi-rational protein engineering approach, we augmented the catalytic activity of CrMAS and attained ~ 10-folds higher production level on glucose. When applied together, protein engineering with enhanced precursor supplies resulted in more than 20-folds increase in total amyrins. We also investigated the effects of different fermentation conditions in flask cultures, including temperature, volumetric oxygen mass transfer coefficient and carbon source types. The optimized fermentation condition attained titers of at least 100 mg/L α-amyrin and 20 mg/L β-amyrin. CONCLUSIONS The design workflow demonstrated herein is simple and remarkably effective in amplifying triterpenoid biosynthesis in the yeast Y. lipolytica.
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Affiliation(s)
- Jing Kong
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China
| | - Lin Miao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China
| | - Zhihui Lu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China
| | - Shuhui Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China
| | - Baixiang Zhao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China
| | - Cuiying Zhang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China
| | - Dongguang Xiao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China
| | - Desmond Teo
- Food, Chemical and Biotechnology Cluster, Singapore Institute of Technology, Singapore, 138683, Singapore
| | - Susanna Su Jan Leong
- Food, Chemical and Biotechnology Cluster, Singapore Institute of Technology, Singapore, 138683, Singapore
| | - Adison Wong
- Food, Chemical and Biotechnology Cluster, Singapore Institute of Technology, Singapore, 138683, Singapore.
| | - Aiqun Yu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, No.29 the 13th Street TEDA, Tianjin, 300457, People's Republic of China.
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4
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Mali H, Shah C, Rudakiya DM, Patel DH, Trivedi U, Subramanian RB. A novel organophosphate hydrolase from Arthrobacter sp. HM01: Characterization and applications. BIORESOURCE TECHNOLOGY 2022; 349:126870. [PMID: 35192947 DOI: 10.1016/j.biortech.2022.126870] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 06/14/2023]
Abstract
Bioremediation systems coupled to efficient microbial enzymes have emerged as an attractive approach for the in-situ removal of hazardous organophosphates (OPs) pesticides from the polluted environment. However, the role of engineered enzymes in OPs-degradation is rarely studied. In this study, the potential OPs-hydrolase (opdH) gene (Arthrobacter sp. HM01) was isolated, cloned, expressed, and purified. The recombinant organophosphate hydrolase (ropdH) was ∼29 kDa; which catalyzed a broad-range of OPs-pesticides in organic-solvent (∼99 % in 30 min), and was found to increase the catalytic efficiency by 10-folds over the native enzyme (kcat/Km: 107 M-1s-1). The degraded metabolites were analyzed using HPLC/GCMS. Through site-directed mutagenesis, it was confirmed that, conserved metal-bridged residue (Lys-127), plays a crucial role in OPs-degradation, which shows ∼18-folds decline in OPs-degradation. Furthermore, the catalytic activity and its stability has been enhanced by >2.0-fold through biochemical optimization. Thus, the study suggests that ropdH has all the required properties for OPs bioremediation.
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Affiliation(s)
- Himanshu Mali
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol, Gujarat 388 315, India
| | - Chandni Shah
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol, Gujarat 388 315, India
| | - Darshan M Rudakiya
- Synergy Cignpost Diagnostics, 3 Mills Studio, London, E3 3DU, United Kingdom
| | - Darshan H Patel
- Charotar Institute of Paramedical Sciences, Charotar University of Science and Technology, (CHARUSAT), Changa, Gujarat 388421, India
| | - Ujjval Trivedi
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol, Gujarat 388 315, India
| | - R B Subramanian
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol, Gujarat 388 315, India.
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Wang Y, Wang J, Zhang Z, Yang J, Turunen O, Xiong H. High-temperature behavior of hyperthermostable Thermotoga maritima xylanase XYN10B after designed and evolved mutations. Appl Microbiol Biotechnol 2022; 106:2017-2027. [PMID: 35171339 DOI: 10.1007/s00253-022-11823-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 01/29/2022] [Accepted: 02/05/2022] [Indexed: 11/24/2022]
Abstract
A hyperthermostable xylanase XYN10B from Thermotoga maritima (PDB code 1VBR, GenBank accession number KR078269) was subjected to site-directed and error-prone PCR mutagenesis. From the selected five mutants, the two site-directed mutants (F806H and F806V) showed a 3.3-3.5-fold improved enzyme half-life at 100 °C. The mutant XYNA generated by error-prone PCR showed slightly improved stability at 100 °C and a lower Km. In XYNB and XYNC, the additional mutations over XYNA decreased the thermostability and temperature optimum, while elevating the Km. In XYNC, two large side-chains were introduced into the protein's interior. Micro-differential scanning calorimetry (DSC) showed that the melting temperature (Tm) dropped in XYNB and XYNC from 104.9 °C to 93.7 °C and 78.6 °C, respectively. The detrimental mutations showed that extremely thermostable enzymes can tolerate quite radical mutations in the protein's interior and still retain high thermostability. The analysis of mutations (F806H and F806V) in a hydrophobic area lining the substrate-binding region indicated that active site hydrophobicity is important for high activity at extreme temperatures. Although polar His at 806 provided higher stability, the hydrophobic Phe at 806 provided higher activity than His. This study generates an understanding of how extreme thermostability and high activity are formed in GH10 xylanases. KEY POINTS: • Characterization and molecular dynamics simulations of TmXYN10B and its mutants • Explanation of structural stability of GH10 xylanase.
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Affiliation(s)
- Yawei Wang
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430048, China
| | - Jing Wang
- College of Life Science, South-central University for Nationalities, Wuhan, 430074, China
| | - Zhongqiang Zhang
- College of Life Science, South-central University for Nationalities, Wuhan, 430074, China
| | - Jiangke Yang
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430048, China
| | - Ossi Turunen
- School of Forest Sciences, University of Eastern Finland, FI-80101, Joensuu, Finland.
| | - Hairong Xiong
- College of Life Science, South-central University for Nationalities, Wuhan, 430074, China.
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Gufe C, Sutthibutpong T, Muhammad A, Ngenyoung A, Rattanarojpong T, Khunrae P. Role of F124 in the inhibition of Bacillus firmus K-1 Xyn11A by monomeric aromatic phenolic compounds. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.102147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Patel DK, Patel K, Patel D, Dave G. Engineering of thermostable phytase-xylanase for hydrolysis of complex biopolymers. 3 Biotech 2021; 11:390. [PMID: 34458060 DOI: 10.1007/s13205-021-02936-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 07/20/2021] [Indexed: 10/20/2022] Open
Abstract
Industrial processing of enzymes requires higher heating that affects the thermal stability of the enzyme and increases the production cost. In this study, xylanase-phytase (XP) fusion protein was generated via co-expression in a single vector with a cold-shock promoter, leading to improved activity at optimal pH, temperature and the thermal behaviour of the protein. Xylanase-phytase (XP) fusion and phytase proteins were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The XP fusion was thermally stable up to 124 °C, higher than phytase which was steady up to 113.5 °C. XP fusion exhibits higher stability at its thermal transition midpoint (T m) 108 °C, higher than the T m value of phytase which is 90 °C. Industrially efficient and environment-friendly proteins with low production cost and higher stability can be generated by 'fusion protein' technology. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13205-021-02936-z.
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Ngenyoung A, Muhammad A, Rattanarojpong T, Sutthibutpong T, Khunrae P. Effect of N-terminal modification on the mode of action between the Xyn11A and Xylotetraose. Int J Biol Macromol 2020; 170:240-247. [PMID: 33359611 DOI: 10.1016/j.ijbiomac.2020.12.154] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/16/2020] [Accepted: 12/20/2020] [Indexed: 11/24/2022]
Abstract
The purpose of this study was to gain an insight into the effects of mutation-induced binding pocket tilting of the Xyn11A xylanase from Bacillus firmus K-1 in producing a unique hydrolysis characteristic. In this study, the wildtype Xyn11A and its K40L mutant were compared for their hydrolysis patterns on beechwood xylan and xylooligosaccharides of sizes 2 to 6. According to our thin-layer chromatography experiment, the K40L mutant produced a larger amount of xylotetraose leftover than the wildtype. Kinetic determination of the WT and K40L mutant suggested that the higher X4 leftover on TLC was reflected in the decreasing catalytic efficiency (kcat/Km) between enzyme and X4. The mechanisms underlying this efficiency loss were examined through atomistic molecular dynamics (MD) simulations. The MD trajectory analysis showed that the mutation-induced binding pocket tilting resulted in an additional hydrophobic contact between the reducing end of X4 and Trp128. Meanwhile, the interactions between the non-reducing end and the Arg112 residue near the active site became lost, which could decrease the catalytic efficiency. This work suggested that the protein engineering to fine-tune the hydrolysis pattern for some desired xylooligosaccharide products was possible.
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Affiliation(s)
- Apichet Ngenyoung
- Department of Microbiology, Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok 10140, Thailand
| | - Auwal Muhammad
- Theoretical and Computational Physics Group, Department of Physics, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok 10140, Thailand; Theoretical and Computational Science Center (TaCS), Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), 126 Pracha-Uthit Road, Bang Mod, Thrung Khru, Bangkok 10140, Thailand; Department of Physics, Faculty of Science, Kano University of Science and Technology (KUST), Wudil, Nigeria
| | - Triwit Rattanarojpong
- Department of Microbiology, Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok 10140, Thailand
| | - Thana Sutthibutpong
- Theoretical and Computational Physics Group, Department of Physics, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok 10140, Thailand; Theoretical and Computational Science Center (TaCS), Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), 126 Pracha-Uthit Road, Bang Mod, Thrung Khru, Bangkok 10140, Thailand
| | - Pongsak Khunrae
- Department of Microbiology, Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok 10140, Thailand.
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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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10
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Shen S, Zhang X, Li Z. Development of an engineered carbamoyl phosphate synthetase with released sensitivity to feedback inhibition by site-directed mutation and casting error-prone PCR. Enzyme Microb Technol 2019; 129:109354. [PMID: 31307577 DOI: 10.1016/j.enzmictec.2019.05.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/30/2019] [Accepted: 05/26/2019] [Indexed: 12/26/2022]
Abstract
Carbamoyl phosphate synthetase (CPS) is a key enzyme in both pyrimidine and arginine biosynthesis. However, it is inhibited strongly by uridine monophosphate (UMP), which is an intermediate of the de-novo synthesis of pyrimidine nucleoside. In this study, the native carbamoyl phosphate synthetase, from Escherichia coli, was evolved by site-directed mutation and casting error-prone PCR. Compared with the wild-type, the variant N1015 F had released sensitivity to UMP and exhibited 100% of the initial activity in the presence of UMP. Variant K1006A exhibited 0.14-fold improvement in initial activity and kept above 65% of relative activity under the saturated concentration of inhibitor. Structure analysis of variants demonstrated that the reduced sensitivity to inhibitor was largely attributed to the decreased hydrogen bonds, which could reduce the binding affinity with UMP. Also, Phe with large side chain could narrow the binding pocket and generate more steric hindrance. Based on the results in this study, N1015F was an ideal alternative catalyst for the wild-type CPS for pyrimidine biosynthesis.
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Affiliation(s)
- Su Shen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Xing Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Zhimin Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai 200237, China.
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