1
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Cannon JA, Zhou Y, Qualey LT, Reynolds TB. Surface-associated residues in subtilisins contribute to poly-L-lactic acid depolymerization via enzyme adsorption. Microb Biotechnol 2024; 17:e14473. [PMID: 38877615 PMCID: PMC11178483 DOI: 10.1111/1751-7915.14473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/22/2024] [Accepted: 04/14/2024] [Indexed: 06/16/2024] Open
Abstract
Poly-L-lactic acid (PLLA) is currently the most abundant bioplastic; however, limited environmental biodegradability and few recycling options diminish its value as a biodegradable commodity. Enzymatic recycling is one strategy for ensuring circularity of PLLA, but this approach requires a thorough understanding of enzymatic mechanisms and protein engineering strategies to enhance activity. In this study, we engineer PLLA depolymerizing subtilisin enzymes originating from Bacillus species to elucidate the molecular mechanisms dictating their PLLA depolymerization activity and to improve their function. The surface-associated amino acids of two closely related subtilisin homologues originating from Bacillus subtilis (BsAprE) and Bacillus pumilus (BpAprE) were compared, as they were previously engineered to have nearly identical active sites, but still varied greatly in PLLA depolymerizing activity. Further analysis identified several surface-associated amino acids in BpAprE that lead to enhanced PLLA depolymerization activity when engineered into BsAprE. In silico protein modelling demonstrated increased enzyme surface hydrophobicity in engineered BsAprE variants and revealed a structural motif favoured for PLLA depolymerization. Experimental evidence suggests that increases in activity are associated with enhanced polymer binding as opposed to substrate specificity. These data highlight enzyme adsorption as a key factor in PLLA depolymerization by subtilisins.
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Affiliation(s)
- Jordan A Cannon
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
| | - Yue Zhou
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
| | - Luke T Qualey
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
| | - Todd B Reynolds
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
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2
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Rahmati F, Sethi D, Shu W, Asgari Lajayer B, Mosaferi M, Thomson A, Price GW. Advances in microbial exoenzymes bioengineering for improvement of bioplastics degradation. CHEMOSPHERE 2024; 355:141749. [PMID: 38521099 DOI: 10.1016/j.chemosphere.2024.141749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 03/06/2024] [Accepted: 03/16/2024] [Indexed: 03/25/2024]
Abstract
Plastic pollution has become a major global concern, posing numerous challenges for the environment and wildlife. Most conventional ways of plastics degradation are inefficient and cause great damage to ecosystems. The development of biodegradable plastics offers a promising solution for waste management. These plastics are designed to break down under various conditions, opening up new possibilities to mitigate the negative impact of traditional plastics. Microbes, including bacteria and fungi, play a crucial role in the degradation of bioplastics by producing and secreting extracellular enzymes, such as cutinase, lipases, and proteases. However, these microbial enzymes are sensitive to extreme environmental conditions, such as temperature and acidity, affecting their functions and stability. To address these challenges, scientists have employed protein engineering and immobilization techniques to enhance enzyme stability and predict protein structures. Strategies such as improving enzyme and substrate interaction, increasing enzyme thermostability, reinforcing the bonding between the active site of the enzyme and substrate, and refining enzyme activity are being utilized to boost enzyme immobilization and functionality. Recently, bioengineering through gene cloning and expression in potential microorganisms, has revolutionized the biodegradation of bioplastics. This review aimed to discuss the most recent protein engineering strategies for modifying bioplastic-degrading enzymes in terms of stability and functionality, including enzyme thermostability enhancement, reinforcing the substrate binding to the enzyme active site, refining with other enzymes, and improvement of enzyme surface and substrate action. Additionally, discovered bioplastic-degrading exoenzymes by metagenomics techniques were emphasized.
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Affiliation(s)
- Farzad Rahmati
- Department of Microbiology, Faculty of Science, Qom Branch, Islamic Azad University (IAU), Qom 37185364, Iran
| | - Debadatta Sethi
- Sugarcane Research Station, Odisha University of Agriculture and Technology, Nayagarh, India
| | - Weixi Shu
- Faculty of Agriculture, Dalhousie University, Truro, NS, B2N 5E3, Canada
| | | | - Mohammad Mosaferi
- Health and Environment Research Center, Tabriz Health Services Management Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Allan Thomson
- Perennia Food and Agriculture Corporation., 173 Dr. Bernie MacDonald Dr., Bible Hill, Truro, NS, B6L 2H5, Canada
| | - G W Price
- Faculty of Agriculture, Dalhousie University, Truro, NS, B2N 5E3, Canada.
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3
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Choi J, Kim H, Ahn YR, Kim M, Yu S, Kim N, Lim SY, Park JA, Ha SJ, Lim KS, Kim HO. Recent advances in microbial and enzymatic engineering for the biodegradation of micro- and nanoplastics. RSC Adv 2024; 14:9943-9966. [PMID: 38528920 PMCID: PMC10961967 DOI: 10.1039/d4ra00844h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 03/19/2024] [Indexed: 03/27/2024] Open
Abstract
This review examines the escalating issue of plastic pollution, specifically highlighting the detrimental effects on the environment and human health caused by microplastics and nanoplastics. The extensive use of synthetic polymers such as polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS) has raised significant environmental concerns because of their long-lasting and non-degradable characteristics. This review delves into the role of enzymatic and microbial strategies in breaking down these polymers, showcasing recent advancements in the field. The intricacies of enzymatic degradation are thoroughly examined, including the effectiveness of enzymes such as PETase and MHETase, as well as the contribution of microbial pathways in breaking down resilient polymers into more benign substances. The paper also discusses the impact of chemical composition on plastic degradation kinetics and emphasizes the need for an approach to managing the environmental impact of synthetic polymers. The review highlights the significance of comprehending the physical characteristics and long-term impacts of micro- and nanoplastics in different ecosystems. Furthermore, it points out the environmental and health consequences of these contaminants, such as their ability to cause cancer and interfere with the endocrine system. The paper emphasizes the need for advanced analytical methods and effective strategies for enzymatic degradation, as well as continued research and development in this area. This review highlights the crucial role of enzymatic and microbial strategies in addressing plastic pollution and proposes methods to create effective and environmentally friendly solutions.
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Affiliation(s)
- Jaewon Choi
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Hongbin Kim
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Yu-Rim Ahn
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Minse Kim
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Seona Yu
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Nanhyeon Kim
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Su Yeon Lim
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Jeong-Ann Park
- Department of Environmental Engineering, Kangwon National University Chuncheon 24341 Republic of Korea
| | - Suk-Jin Ha
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Kwang Suk Lim
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
| | - Hyun-Ouk Kim
- Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University Chuncheon Korea
- Department of Smart Health Science and Technology, Kangwon National University Chuncheon Korea
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4
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Choi SY, Lee Y, Yu HE, Cho IJ, Kang M, Lee SY. Sustainable production and degradation of plastics using microbes. Nat Microbiol 2023; 8:2253-2276. [PMID: 38030909 DOI: 10.1038/s41564-023-01529-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023]
Abstract
Plastics are indispensable in everyday life and industry, but the environmental impact of plastic waste on ecosystems and human health is a huge concern. Microbial biotechnology offers sustainable routes to plastic production and waste management. Bacteria and fungi can produce plastics, as well as their constituent monomers, from renewable biomass, such as crops, agricultural residues, wood and organic waste. Bacteria and fungi can also degrade plastics. We review state-of-the-art microbial technologies for sustainable production and degradation of bio-based plastics and highlight the potential contributions of microorganisms to a circular economy for plastics.
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Affiliation(s)
- So Young Choi
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for BioCentury, KAIST, Daejeon, Republic of Korea
- BioProcess Engineering Research Center, KAIST, Daejeon, Republic of Korea
| | - Youngjoon Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for BioCentury, KAIST, Daejeon, Republic of Korea
- BioProcess Engineering Research Center, KAIST, Daejeon, Republic of Korea
| | - Hye Eun Yu
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for BioCentury, KAIST, Daejeon, Republic of Korea
| | - In Jin Cho
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for BioCentury, KAIST, Daejeon, Republic of Korea
- BioProcess Engineering Research Center, KAIST, Daejeon, Republic of Korea
| | - Minju Kang
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for BioCentury, KAIST, Daejeon, Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Four), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
- KAIST Institute for BioCentury, KAIST, Daejeon, Republic of Korea.
- BioProcess Engineering Research Center, KAIST, Daejeon, Republic of Korea.
- BioInformatics Research Center, KAIST, Daejeon, Republic of Korea.
- Graduate School of Engineering Biology, KAIST, Daejeon, Republic of Korea.
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5
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Lai J, Huang H, Lin M, Xu Y, Li X, Sun B. Enzyme catalyzes ester bond synthesis and hydrolysis: The key step for sustainable usage of plastics. Front Microbiol 2023; 13:1113705. [PMID: 36713200 PMCID: PMC9878459 DOI: 10.3389/fmicb.2022.1113705] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 12/29/2022] [Indexed: 01/15/2023] Open
Abstract
Petro-plastic wastes cause serious environmental contamination that require effective solutions. Developing alternatives to petro-plastics and exploring feasible degrading methods are two solving routes. Bio-plastics like polyhydroxyalkanoates (PHAs), polylactic acid (PLA), polycaprolactone (PCL), poly (butylene succinate) (PBS), poly (ethylene furanoate) s (PEFs) and poly (ethylene succinate) (PES) have emerged as promising alternatives. Meanwhile, biodegradation plays important roles in recycling plastics (e.g., bio-plastics PHAs, PLA, PCL, PBS, PEFs and PES) and petro-plastics poly (ethylene terephthalate) (PET) and plasticizers in plastics (e.g., phthalate esters, PAEs). All these bio- and petro-materials show structure similarity by connecting monomers through ester bond. Thus, this review focused on bio-plastics and summarized the sequences and structures of the microbial enzymes catalyzing ester-bond synthesis. Most of these synthetic enzymes belonged to α/β-hydrolases with conserved serine catalytic active site and catalyzed the polymerization of monomers by forming ester bond. For enzymatic plastic degradation, enzymes about PHAs, PBS, PCL, PEFs, PES and PET were discussed, and most of the enzymes also belonged to the α/β hydrolases with a catalytic active residue serine, and nucleophilically attacked the ester bond of substrate to generate the cleavage of plastic backbone. Enzymes hydrolysis of the representative plasticizer PAEs were divided into three types (I, II, and III). Type I enzymes hydrolyzed only one ester-bond of PAEs, type II enzymes catalyzed the ester-bond of mono-ester phthalates, and type III enzymes hydrolyzed di-ester bonds of PAEs. Divergences of catalytic mechanisms among these enzymes were still unclear. This review provided references for producing bio-plastics, and degrading or recycling of bio- and petro-plastics from an enzymatic point of view.
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Affiliation(s)
- Jinghui Lai
- Key Laboratory of Brewing Microbiology and Enzymatic Molecular Engineering of China General Chamber of Commence, Beijing Technology and Business University, Beijing, China
| | - Huiqin Huang
- Key Laboratory of Brewing Microbiology and Enzymatic Molecular Engineering of China General Chamber of Commence, Beijing Technology and Business University, Beijing, China
| | - Mengwei Lin
- Key Laboratory of Brewing Microbiology and Enzymatic Molecular Engineering of China General Chamber of Commence, Beijing Technology and Business University, Beijing, China
| | - Youqiang Xu
- Key Laboratory of Brewing Microbiology and Enzymatic Molecular Engineering of China General Chamber of Commence, Beijing Technology and Business University, Beijing, China
| | - Xiuting Li
- Key Laboratory of Brewing Microbiology and Enzymatic Molecular Engineering of China General Chamber of Commence, Beijing Technology and Business University, Beijing, China
- Key Laboratory of Brewing Molecular Engineering of China Light Industry, Beijing Technology and Business University, Beijing, China
| | - Baoguo Sun
- Key Laboratory of Brewing Microbiology and Enzymatic Molecular Engineering of China General Chamber of Commence, Beijing Technology and Business University, Beijing, China
- Key Laboratory of Brewing Molecular Engineering of China Light Industry, Beijing Technology and Business University, Beijing, China
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6
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Zhu B, Wang D, Wei N. Enzyme Discovery and Engineering for Sustainable Plastic Recycling. Trends Biotechnol 2021; 40:22-37. [PMID: 33676748 DOI: 10.1016/j.tibtech.2021.02.008] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 10/22/2022]
Abstract
The drastically increasing amount of plastic waste is causing an environmental crisis that requires innovative technologies for recycling post-consumer plastics to achieve waste valorization while meeting environmental quality goals. Biocatalytic depolymerization mediated by enzymes has emerged as an efficient and sustainable alternative for plastic treatment and recycling. A variety of plastic-degrading enzymes have been discovered from microbial sources. Meanwhile, protein engineering has been exploited to modify and optimize plastic-degrading enzymes. This review highlights the recent trends and up-to-date advances in mining novel plastic-degrading enzymes through state-of-the-art omics-based techniques and improving the enzyme catalytic efficiency and stability via various protein engineering strategies. Future research prospects and challenges are also discussed.
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Affiliation(s)
- Baotong Zhu
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, USA
| | - Dong Wang
- Department of Computer Science and Engineering, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, USA
| | - Na Wei
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, USA.
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7
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The role of enzyme adsorption in the enzymatic degradation of an aliphatic polyester. Enzyme Microb Technol 2019; 120:110-116. [DOI: 10.1016/j.enzmictec.2018.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 10/10/2018] [Accepted: 10/12/2018] [Indexed: 11/19/2022]
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8
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Lee MC, Liu EJ, Yang CH, Hsiao LJ, Wu TM, Li SY. Co-Expression of ORF Cma with PHB Depolymerase (PhaZ Cma ) in Escherichia coli Induces Efficient Whole-Cell Biodegradation of Polyesters. Biotechnol J 2018; 13:e1700560. [PMID: 29337429 DOI: 10.1002/biot.201700560] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 12/10/2017] [Indexed: 11/07/2022]
Abstract
Whole-cell degradation of polyesters not only avoids the tedious process of enzyme separation, but also allows the degraded product to be reused as a carbon source. In this study, Escherichia coli BL21(DE3) harboring phaZCma , a gene encoding poly(3-hydroxybutyrate) (PHB) depolymerase from Caldimonas manganoxidans, is constructed. The extra-cellular fraction of E. coli/pPHAZ exhibits a fast PHB degradation rate where it only took 35 h to completely degrade PHB films, while C. manganoxidans takes 81 h to do the same. The co-expression of ORFCma (a putative periplasmic substrate binding protein that is within the same operon of phaZCma ) further improves the PHB degradation. While 28 h is needed for E. coli/pPHAZ to cause an 80% weight loss in PHB films, E. coli/pORFPHAZ needs only 21 h. Furthermore, it is able to degrade at-least four different polyesters, PHB, poly(lactic acid) (PLA), polycaprolactone (PCL), and poly(butylene succinate-co-adipate) (PBSA). Testing of the time course of 3-hydroxybutyrate concentration and the turbidity of the degradation solutions over time shows that PhaZCma has both exo- and endo-enzymatic activity. The whole-cell E. coli/pORFPHAZ can be used for recycling various polyesters while ORFCma can potentially be a universal element for enhancing the secretion of recombinant protein.
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Affiliation(s)
- Ming-Chieh Lee
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 402, Taiwan
| | - En-Jung Liu
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 402, Taiwan
| | - Cheng-Han Yang
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 402, Taiwan
| | - Li-Jung Hsiao
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 402, Taiwan
| | - Tzong-Ming Wu
- Department of Materials Science and Engineering, National Chung Hsing University, Taichung, 402, Taiwan
| | - Si-Yu Li
- Department of Chemical Engineering, National Chung Hsing University, Taichung, 402, Taiwan
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9
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Zhang X, Fevre M, Jones GO, Waymouth RM. Catalysis as an Enabling Science for Sustainable Polymers. Chem Rev 2017; 118:839-885. [DOI: 10.1021/acs.chemrev.7b00329] [Citation(s) in RCA: 472] [Impact Index Per Article: 67.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Xiangyi Zhang
- Department
of Chemistry, Stanford University, Stanford, California 94305-5080, United States
| | - Mareva Fevre
- IBM Research−Almaden, 650 Harry Road, San Jose, California 95120, United States
| | - Gavin O. Jones
- IBM Research−Almaden, 650 Harry Road, San Jose, California 95120, United States
| | - Robert M. Waymouth
- Department
of Chemistry, Stanford University, Stanford, California 94305-5080, United States
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10
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Influence of surface charge, binding site residues and glycosylation on Thielavia terrestris cutinase biochemical characteristics. Appl Microbiol Biotechnol 2016; 100:4435-46. [PMID: 26758295 DOI: 10.1007/s00253-015-7254-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 09/13/2015] [Accepted: 12/12/2015] [Indexed: 02/06/2023]
Abstract
Cutinases are esterases of industrial importance for applications in recycling and surface modification of polyesters. The cutinase from Thielavia terrestris (TtC) is distinct in terms of its ability to retain its stability and activity in acidic pH. Stability and activity in acidic pHs are desirable for esterases as the pH of the reaction tends to go down with the generation of acid. The pH stability and activity are governed by the charged state of the residues involved in catalysis or in substrate binding. In this study, we performed the detailed structural and biochemical characterization of TtC coupled with surface charge analysis to understand its acidic tolerance. The stability of TtC in acidic pH was rationalized by evaluating the contribution of charge interactions to the Gibbs free energy of unfolding at varying pHs. The activity of TtC was found to be limited by substrate binding affinity, which is a function of the surface charge. Additionally, the presence of glycosylation affects the biochemical characteristics of TtC owing to steric interactions with residues involved in substrate binding.
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11
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Panagiotidou E, Konidaris C, Baklavaridis A, Zuburtikudis I, Achilias D, Mitlianga P. A Simple Route for Purifying Extracellular Poly(3-hydroxybutyrate)-depolymerase from Penicillium pinophilum. Enzyme Res 2014; 2014:159809. [PMID: 25328684 PMCID: PMC4190121 DOI: 10.1155/2014/159809] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/10/2014] [Accepted: 09/10/2014] [Indexed: 11/17/2022] Open
Abstract
This work proposes the purification of an active and efficient enzyme, extracellular poly(3-hydroxybutyrate) (PHB)-depolymerase, suitable for industrial applications. This is achieved by the application of an easy, fast, and cheap route, skipping the chromatography step. Chromatography with one or two columns is a common step in the purification procedure, which however renders the isolation of the enzyme a time consuming and an expensive process. A strain of the fungus Penicillium pinophilum (ATCC 9644) is used for the isolation of extracellular PHB-depolymerase. The molecular weight of the purified enzyme is about 35 kDa and is estimated by gel electrophoresis (SDS-PAGE, 12% polyacrylamide). The enzymatic activity of the isolated enzyme is determined to be 3.56-fold similar to that found by other researchers that have used chromatography for the isolation. The as-isolated enzyme disintegrates the poly(3-hydroxybutyrate) (PHB) films successfully, as it is demonstrated by the biodegradation test results provided here.
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Affiliation(s)
- Elpiniki Panagiotidou
- Department of Mechanical and Industrial Design Engineering, TEI of Western Macedonia, 50100 Kozani, Greece
- Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Constantinos Konidaris
- Laboratory of Biotechnology, Department of Biological Applications and Technologies, University of Ioannina, 45100 Ioannina, Greece
- Laboratory of Biochemistry, Department of Biological Applications and Technologies, University of Ioannina, 45100 Ioannina, Greece
| | - Apostolos Baklavaridis
- Department of Mechanical and Industrial Design Engineering, TEI of Western Macedonia, 50100 Kozani, Greece
| | - Ioannis Zuburtikudis
- Department of Mechanical and Industrial Design Engineering, TEI of Western Macedonia, 50100 Kozani, Greece
- Department of Chemical and Petroleum Engineering, United Arab Emirates University, Al Ain, UAE
| | - Dimitris Achilias
- Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Paraskevi Mitlianga
- Depertment of Agricultural Technology, School of Agriculture Technology, Food Technology and Nutrition, TEI of Western Macedonia, Terma Kontopoulou, 53100 Florina, Greece
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12
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Tan LT, Hiraishi T, Sudesh K, Maeda M. Effects of mutation at position 285 of Ralstonia pickettii T1 poly[(R)-3-hydroxybutyrate] depolymerase on its activities. Appl Microbiol Biotechnol 2014; 98:7061-8. [PMID: 24676749 DOI: 10.1007/s00253-014-5660-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 02/28/2014] [Accepted: 03/02/2014] [Indexed: 11/26/2022]
Abstract
Asn at position 285 (N285) in the catalytic domain of poly[(R)-3-hydroxybutyrate] (PHB) depolymerase from Ralstonia pickettii T1 most likely participates in the cleavage of ester bonds as revealed by our previous evolutionary engineering study using the error-prone polymerase chain reaction (PCR) method. To exhaustively examine the effects of mutations at that position, we conducted site-directed saturation mutagenesis at that position and the resultant mutant enzymes (N285X) were evaluated in p-nitrophenyl ester (pNPCn) hydrolysis and PHB degradation. Kinetic studies demonstrated that the PHB-degrading activities of N285X were reciprocally related to their pNPCn-hydrolyzing activities, with the exception of N285A and N285G, and that His residue could functionally substitute for Asn285 on PHB degradation.
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Affiliation(s)
- Liu-Tzea Tan
- Bioengineering Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan
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13
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Sreedevi S, Unni KN, Sajith S, Priji P, Josh MS, Benjamin S. Bioplastics: Advances in Polyhydroxybutyrate Research. ADVANCES IN POLYMER SCIENCE 2014. [DOI: 10.1007/12_2014_297] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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14
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Tan LT, Hiraishi T, Sudesh K, Maeda M. Directed evolution of poly[(R)-3-hydroxybutyrate] depolymerase using cell surface display system: functional importance of asparagine at position 285. Appl Microbiol Biotechnol 2012; 97:4859-71. [DOI: 10.1007/s00253-012-4366-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 08/10/2012] [Accepted: 08/12/2012] [Indexed: 12/01/2022]
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15
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Hiraishi T, Yamashita K, Sakono M, Nakanishi J, Tan LT, Sudesh K, Abe H, Maeda M. Display of Functionally Active PHB Depolymerase on Escherichia Coli
Cell Surface. Macromol Biosci 2011; 12:218-24. [DOI: 10.1002/mabi.201100273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 09/09/2011] [Indexed: 11/11/2022]
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