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Zeng J, Guo J, Yuan L. Engineering of the Phytase YiAPPA to Improve Thermostability and Activity and Its Application Potential in Dephytinization of Food Ingredients. J Microbiol Biotechnol 2024; 34:1660-1670. [PMID: 39081259 PMCID: PMC11380507 DOI: 10.4014/jmb.2403.03031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 05/30/2024] [Accepted: 06/14/2024] [Indexed: 08/29/2024]
Abstract
The aim of this study was to modify phytase YiAPPA via protein surficial residue mutation to obtain phytase mutants with improved thermostability and activity, enhancing its application potential in the food industry. First, homology modeling of YiAPPA was performed. By adopting the strategy of protein surficial residue mutation, the lysine (Lys) and glycine (Gly) residues on the protein surface were selected for site-directed mutagenesis to construct single-site mutants. Thermostability screening was performed to obtain mutants (K189R and K216R) with significantly elevated thermostability. The combined mutant K189R/K216R was constructed via beneficial mutation site stacking and characterized. Compared with those of YiAPPA, the half-life of K189R/K216R at 80°C was extended from 14.81 min to 23.35 min, half-inactivation temperature (T50 30) was increased from 55.12°C to 62.44°C, and Tm value was increased from 48.36°C to 53.18°C. Meanwhile, the specific activity of K189R/K216R at 37°C and pH 4.5 increased from 3960.81 to 4469.13 U/mg. Molecular structure modeling analysis and molecular dynamics simulation showed that new hydrogen bonds were introduced into K189R/K216R, improving the stability of certain structural units of the phytase and its thermostability. The enhanced activity was primarily attributed to reduced enzyme-substrate binding energy and shorter nucleophilic attack distance between the catalytic residue His28 and the phytate substrate. Additionally, the K189R/K216R mutant increased the hydrolysis efficiency of phytate in food ingredients by 1.73-2.36 times. This study established an effective method for the molecular modification of phytase thermostability and activity, providing the food industry with an efficient phytase for hydrolyzing phytate in food ingredients.
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Affiliation(s)
- Jing Zeng
- Institute of Microbiology, Jiangxi Academy of Sciences, Nanchang 330096, Jiangxi Province, P.R. China
| | - Jianjun Guo
- Institute of Microbiology, Jiangxi Academy of Sciences, Nanchang 330096, Jiangxi Province, P.R. China
| | - Lin Yuan
- Institute of Microbiology, Jiangxi Academy of Sciences, Nanchang 330096, Jiangxi Province, P.R. China
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2
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Yang T, Hu Q, Liu Y, Xu R, Wang D, Chang Z, Jin M, Huang J. Biochemical characteristics and potential application of a thermostable starch branching enzyme from Bacillus licheniformis. AMB Express 2023; 13:8. [PMID: 36662316 PMCID: PMC9859979 DOI: 10.1186/s13568-023-01511-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 01/08/2023] [Indexed: 01/21/2023] Open
Abstract
Slowly digestible starch (SDS) has attracted increasing attention for its function of preventing metabolic diseases. Based on transglycosylation, starch branching enzymes (1,4-α-glucan branching enzymes, GBEs, EC 2.4.1.18) can be used to regulate the digestibility of starch. In this study, a GBE gene from Bacillus licheniformis (bl-GBE) was cloned, expressed, purified, and characterized. Sequence analysis and structural modeling showed that bl-GBE belong to the glycoside hydrolase 13 (GH13) family, with which its active site residues were conserved. The bl-GBE was highly active at 80 °C and a pH range of 7.5-9.0, and retained 90% of enzyme activity at 70 °C for 16 h. bl-GBE also showed high substrate specificity (80.88 U/mg) on potato starch. The stability and the changes of the secondary structure of bl-GBE at different temperature were determined by circular dichroism (CD) spectroscopy. The CD data showed a loss of 20% of the enzyme activity at high temperatures (80 °C), due to the decreased content of the α -helix in the secondary structure. Furthermore, potato starch treated with bl-GBE (300 U/g starch) showed remarkable increase in stability, solubility, and significant reduction viscosity. Meanwhile, the slowly digestible starch content of bl-GBE modified potato starch increased by 53.03% compared with native potato starch. Our results demonstrated the potential applications of thermophilic bl-GBE in food industries.
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Affiliation(s)
- Ting Yang
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
| | - Qianyu Hu
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
| | - Yu Liu
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
| | - Rui Xu
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
| | - Dongrui Wang
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
| | - Zhongyi Chang
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
| | - Mingfei Jin
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
| | - Jing Huang
- grid.22069.3f0000 0004 0369 6365School of Life Sciences, East China Normal University, Shanghai, 200241 China
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Mashhadi Farahani S, Dadmehr M, Ali Karimi M, Korouzhdehi B, Amin Karimi M, Rajabian M. Fluorometric detection of phytase enzyme activity and phosphate ion based on gelatin supported silver nanoclusters. Food Chem 2022; 396:133711. [PMID: 35853372 DOI: 10.1016/j.foodchem.2022.133711] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 07/08/2022] [Accepted: 07/12/2022] [Indexed: 11/04/2022]
Abstract
Phytase is the commercial enzyme for bioconversion of phytate substrate to digestible phosphate ions. Recently silver nanoclusters (AgNCs) have received great attention as the optical transducer nanoparticles in biosensors structure. The novel detection platform was developed to detect the phytase enzyme activity and phosphate ions based on fluorescence quenching of AgNCs. The AgNCs were synthesized through gelatin supported reaction and characterized by TEM, FTIR and XRD analysis. The hydrolytic effect of phytase enzyme and subsequent phosphate release led to suppression of AgNCs fluorescence. The linear range was observed for enzyme in the range of 0.5-5 U/mL with the detection limit of 0.2 U/mL. Also, the same fluorescence quenching effect was observed in the presence of phosphate ion in the linear range of 1 to 16 µM with a detection limit of 0.5 µM. The proposed mechanism showed effectiveness of detection strategy for detection of phytase enzyme and phosphate ion.
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Affiliation(s)
| | - Mehdi Dadmehr
- Department of Biology, Payame Noor University, Tehran, Iran.
| | | | - Behnaz Korouzhdehi
- Department of Biotechnology, College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran
| | - Mohammad Amin Karimi
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Majid Rajabian
- Department of Biology, Payame Noor University, Tehran, Iran
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4
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Li L, Wu W, Deng Z, Zhang S, Guan W. Improved thermostability of lipase Lip2 from Yarrowia lipolytica through disulfide bond design for preparation of medium-long-medium structured lipids. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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5
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Enhancing the thermostability of transglutaminase from Streptomyces mobaraensis based on the rational design of a disulfide bond. Protein Expr Purif 2022; 195-196:106079. [DOI: 10.1016/j.pep.2022.106079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 03/03/2022] [Accepted: 03/05/2022] [Indexed: 11/22/2022]
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6
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Yang LL, Shi HL, Liu F, Wang Z, Chen KL, Chen WS, Niu XR, Kan YC, Yao LG, Tang CD. Gene cloning of a highly active phytase from Lactobacillus plantarum and further improving its catalytic activity and thermostability through protein engineering. Enzyme Microb Technol 2022; 156:109997. [DOI: 10.1016/j.enzmictec.2022.109997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 01/21/2023]
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Song P, Xu W, Wang K, Zhang Y, Wang F, Zhou X, Shi H, Feng W. Cloning, expression and characterization of metalloproteinase HypZn from Aspergillus niger. PLoS One 2021; 16:e0259809. [PMID: 34762700 PMCID: PMC8584677 DOI: 10.1371/journal.pone.0259809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 10/26/2021] [Indexed: 11/18/2022] Open
Abstract
A predicted metalloproteinase gene, HypZn, was cloned from Aspergillus niger CGMCC 3.7193 and expressed in Pichia pastoris GS115, and the physicochemical characteristics of recombinant HypZn were investigated after separation and purification. The results showed that the specific activity of the purified HypZn reached 1859.2 U/mg, and the optimum temperature and pH value of HypZn were 35°C and 7.0, respectively. HypZn remained stable both at 40°C and at pH values between 5.0 and 8.0. The preferred substrate of HypZn was soybean protein isolates, and the Km and Vmax values were 21.5 μmol/mL and 4926.6 μmol/(mL∙min), respectively. HypZn was activated by Co2+ and Zn2+ and inhibited by Cu2+ and Fe2+. The degree of soybean protein isolate hydrolysis reached 14.7%, and the hydrolysates were of uniform molecular weight. HypZn could tolerate 5000 mM NaCl and completely lost its activity after 30 min at 50°C. The enzymological characterizations indicated that HypZn has great application potential in the food industry, especially in fermented food processing.
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Affiliation(s)
- Peng Song
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Wei Xu
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Kuiming Wang
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Yang Zhang
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Fei Wang
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Xiuling Zhou
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Haiying Shi
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Wei Feng
- School of Life Sciences, Liaocheng University, Liaocheng, China
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Zhao T, Yong X, Zhao Z, Dolce V, Li Y, Curcio R. Research status of Bacillus phytase. 3 Biotech 2021; 11:415. [PMID: 34485008 DOI: 10.1007/s13205-021-02964-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/27/2021] [Indexed: 10/20/2022] Open
Abstract
Phytic acid is abundant in seeds, roots and stems of plants, it acts as an anti-nutrient in food and feed industry, since it affects the absorption of nutrients by humans and monogastric animals. Furthermore, phosphorus produced through its decomposition by microorganisms can cause environmental pollution. Phytase degrades phytic acid generating precursors of inositol that can be used in clinical practice; in addition, phytase treatment can minimize the anti-nutritional effect of phytic acid. The use of phytase synthesized from Bacillus is more advantageous due to its high activity. Additionally, its good heat resistance under neutral conditions greatly fills the gap of commercial utilization of acid phytase. In this review, we summarize the latest research results on Bacillus phytase, including its physiological and biochemical characteristics, molecular structure information, calcium effects on its catalytic activity and stability, its catalytic mechanism and molecular modification.
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Affiliation(s)
- Ting Zhao
- College of Life Science and Technology, Xinjiang University, Urumqi, China
- National Facility for Protein Science in Shanghai, Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Science, Shanghai, China
| | - Xihao Yong
- College of Life Science and Technology, Xinjiang University, Urumqi, China
- Faculty of Bioengineering, Sichuan University of Science and Engineering, Zigong, People's Republic of China
| | - Ziming Zhao
- Faculty of Bioengineering, Sichuan University of Science and Engineering, Zigong, People's Republic of China
| | - Vincenza Dolce
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
| | - Yuan Li
- College of Life Science and Technology, Xinjiang University, Urumqi, China
- Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari, Bari, Italy
| | - Rosita Curcio
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
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Wu H, Chen Q, Zhang W, Mu W. Overview of strategies for developing high thermostability industrial enzymes: Discovery, mechanism, modification and challenges. Crit Rev Food Sci Nutr 2021; 63:2057-2073. [PMID: 34445912 DOI: 10.1080/10408398.2021.1970508] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Biocatalysts such as enzymes are environmentally friendly and have substrate specificity, which are preferred in the production of various industrial products. However, the strict reaction conditions in industry including high temperature, organic solvents, strong acids and bases and other harsh environments often destabilize enzymes, and thus substantially compromise their catalytic functions, and greatly restrict their applications in food, pharmaceutical, textile, bio-refining and feed industries. Therefore, developing industrial enzymes with high thermostability becomes very important in industry as thermozymes have more advantages under high temperature. Discovering new thermostable enzymes using genome sequencing, metagenomics and sample isolation from extreme environments, or performing molecular modification of the existing enzymes with poor thermostability using emerging protein engineering technology have become an effective means of obtaining thermozymes. Based on the thermozymes as biocatalytic chips in industry, this review systematically analyzes the ways to discover thermostable enzymes from extreme environment, clarifies various interaction forces that will affect thermal stability of enzymes, and proposes different strategies to improve enzymes' thermostability. Furthermore, latest development in the thermal stability modification of industrial enzymes through rational design strategies is comprehensively introduced from structure-activity relationship point of view. Challenges and future research perspectives are put forward as well.
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Affiliation(s)
- Hao Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Qiuming Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu, China
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10
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Wang S, Meng K, Su X, Hakulinen N, Wang Y, Zhang J, Luo H, Yao B, Huang H, Tu T. Cysteine Engineering of an Endo-polygalacturonase from Talaromyces leycettanus JCM 12802 to Improve Its Thermostability. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:6351-6359. [PMID: 34043362 DOI: 10.1021/acs.jafc.1c01618] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Thermostable enzymes have many advantages for industrial applications. Therefore, in this study, computer-aided design technology was used to improve the thermostability of a highly active endo-polygalacturonase from Talaromyces leycettanus JCM12802 at an optimal temperature of 70 °C. The melting temperature and specific activity of the obtained mutant T316C/G344C were increased by 10 °C and 36.5%, respectively, compared with the wild-type enzyme. The crystal structure of the T316C/G344C mutant showed no formation of a disulfide bond between the introduced cysteines, indicating a different mechanism than the conventional mechanism underlying improved enzyme thermostability. The cysteine substitutions directly formed a new alkyl hydrophobic interaction and caused conformational changes in the side chains of the adjacent residues Asn315 and Thr343, which in turn caused a local reconstruction of hydrogen bonds. This method greatly improved the thermostability of the enzyme without affecting its activity; thus, our findings are of great significance for both theoretical research and practical applications.
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Affiliation(s)
- Sheng Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Key Laboratory of Feed Biotechnology of Ministry of Agriculture and Rural Affairs, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Kun Meng
- Key Laboratory of Feed Biotechnology of Ministry of Agriculture and Rural Affairs, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xiaoyun Su
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Nina Hakulinen
- Department of Chemistry, University of Eastern Finland, Joensuu 80130, Finland
| | - Yaru Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Jie Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huiying Luo
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Bin Yao
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huoqing Huang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Tao Tu
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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Navone L, Vogl T, Luangthongkam P, Blinco JA, Luna-Flores CH, Chen X, von Hellens J, Mahler S, Speight R. Disulfide bond engineering of AppA phytase for increased thermostability requires co-expression of protein disulfide isomerase in Pichia pastoris. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:80. [PMID: 33789740 PMCID: PMC8010977 DOI: 10.1186/s13068-021-01936-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 03/20/2021] [Indexed: 05/07/2023]
Abstract
BACKGROUND Phytases are widely used commercially as dietary supplements for swine and poultry to increase the digestibility of phytic acid. Enzyme development has focused on increasing thermostability to withstand the high temperatures during industrial steam pelleting. Increasing thermostability often reduces activity at gut temperatures and there remains a demand for improved phyases for a growing market. RESULTS In this work, we present a thermostable variant of the E. coli AppA phytase, ApV1, that contains an extra non-consecutive disulfide bond. Detailed biochemical characterisation of ApV1 showed similar activity to the wild type, with no statistical differences in kcat and KM for phytic acid or in the pH and temperature activity optima. Yet, it retained approximately 50% activity after incubations for 20 min at 65, 75 and 85 °C compared to almost full inactivation of the wild-type enzyme. Production of ApV1 in Pichia pastoris (Komagataella phaffi) was much lower than the wild-type enzyme due to the presence of the extra non-consecutive disulfide bond. Production bottlenecks were explored using bidirectional promoters for co-expression of folding chaperones. Co-expression of protein disulfide bond isomerase (Pdi) increased production of ApV1 by ~ 12-fold compared to expression without this folding catalyst and restored yields to similar levels seen with the wild-type enzyme. CONCLUSIONS Overall, the results show that protein engineering for enhanced enzymatic properties like thermostability may result in folding complexity and decreased production in microbial systems. Hence parallel development of improved production strains is imperative to achieve the desirable levels of recombinant protein for industrial processes.
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Affiliation(s)
- Laura Navone
- Faculty of Science, Queensland University of Technology, Brisbane, QLD, Australia.
- ARC Centre of Excellence in Synthetic Biology, Queensland University of Technology, Brisbane, QLD, Australia.
| | - Thomas Vogl
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, Israel
| | | | - Jo-Anne Blinco
- Faculty of Science, Queensland University of Technology, Brisbane, QLD, Australia
| | - Carlos H Luna-Flores
- Faculty of Science, Queensland University of Technology, Brisbane, QLD, Australia
- Bioproton Pty Ltd, Brisbane, QLD, Australia
| | | | | | - Stephen Mahler
- ARC Training Centre for Biopharmaceutical Innovation, The University of Queensland, Brisbane, QLD, Australia
| | - Robert Speight
- Faculty of Science, Queensland University of Technology, Brisbane, QLD, Australia
- ARC Centre of Excellence in Synthetic Biology, Queensland University of Technology, Brisbane, QLD, Australia
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12
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Guo LB, Zhu CY, Wu YB, Fan XM, Zhang YW. A novel chondroitin AC lyase from Pedobacter xixiisoli: Cloning, expression, characterization and the application in the preparation of oligosaccharides. Enzyme Microb Technol 2021; 146:109765. [PMID: 33812567 DOI: 10.1016/j.enzmictec.2021.109765] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/08/2021] [Accepted: 02/14/2021] [Indexed: 01/22/2023]
Abstract
Chondroitin AC lyase can efficiently hydrolyze chondroitin sulfate (CS) to low molecule weight chondroitin sulfate, which has been widely used in clinical therapy, including anti-tumor, anti-oxidation, hypolipidemic, and anti-inflammatory. In this work, a novel chondroitin AC lyase from Pedobacter xixiisoli (PxchonAC) was cloned and overexpressed in Escherichia coli BL21 (DE3). The characterization of PxchonAC showed that it has specific activities on chondroitin sulfate A, Chondroitin sulfate C and hyaluronic acid with 428.77, 270.57, and 136.06 U mg-1, respectively. The Km and Vmax of PxchonAC were 0.61 mg mL-1 and 670.18 U mg-1 using chondroitin sulfate A as the substrate. The enzyme had a half-life of roughly 660 min at 37 °C in the presence of Ca2+ and remained a residual activity of 54 % after incubated at 4 °C for 25 days. Molecular docking revealed that Asn123, His223, Tyr232, Arg286, Arg290, Asn372, and Glu374 were mainly involved in the substrate binding. The enzymatic hydrolysis product was analyzed by gel permeation chromatography, demonstrating PxchonAC could hydrolyze CS efficiently.
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Affiliation(s)
- Li-Bin Guo
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Chen-Yuan Zhu
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Yi-Bei Wu
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Xiao-Man Fan
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Ye-Wang Zhang
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China.
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