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Kawai F, Iizuka R, Kawabata T. Engineered polyethylene terephthalate hydrolases: perspectives and limits. Appl Microbiol Biotechnol 2024; 108:404. [PMID: 38953996 PMCID: PMC11219463 DOI: 10.1007/s00253-024-13222-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 06/03/2024] [Accepted: 06/04/2024] [Indexed: 07/04/2024]
Abstract
Polyethylene terephthalate (PET) is a major component of plastic waste. Enzymatic PET hydrolysis is the most ecofriendly recycling technology. The biorecycling of PET waste requires the complete depolymerization of PET to terephthalate and ethylene glycol. The history of enzymatic PET depolymerization has revealed two critical issues for the industrial depolymerization of PET: industrially available PET hydrolases and pretreatment of PET waste to make it susceptible to full enzymatic hydrolysis. As none of the wild-type enzymes can satisfy the requirements for industrialization, various mutational improvements have been performed, through classical technology to state-of-the-art computational/machine-learning technology. Recent engineering studies on PET hydrolases have brought a new insight that flexibility of the substrate-binding groove may improve the efficiency of PET hydrolysis while maintaining sufficient thermostability, although the previous studies focused only on enzymatic thermostability above the glass transition temperature of PET. Industrial biorecycling of PET waste is scheduled to be implemented, using micronized amorphous PET. Next stage must be the development of PET hydrolases that can efficiently degrade crystalline parts of PET and expansion of target PET materials, not only bottles but also textiles, packages, and microplastics. This review discusses the current status of PET hydrolases, their potential applications, and their profespectal goals. KEY POINTS: • PET hydrolases must be thermophilic, but their operation must be below 70 °C • Classical and state-of-the-art engineering approaches are useful for PET hydrolases • Enzyme activity on crystalline PET is most expected for future PET biorecycling.
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Affiliation(s)
- Fusako Kawai
- Graduate School of Environmental and Life Sciences, Okayama University, 1-1-1 Tsushima-Naka, Kita-Ku, Okayama, 700-8530, Japan.
| | - Ryo Iizuka
- Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo, 113-0033, Japan
| | - Takeshi Kawabata
- Graduate School of Information Sciences, Tohoku University, Aoba 6-3-09, Aoba-ku, Sendai, Miyagi, 980-8579, Japan
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2
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Amanna R, Rakshit SK. Review of nomenclature and methods of analysis of polyethylene terephthalic acid hydrolyzing enzymes activity. Biodegradation 2024; 35:341-360. [PMID: 37688750 DOI: 10.1007/s10532-023-10048-z] [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: 03/07/2023] [Accepted: 08/15/2023] [Indexed: 09/11/2023]
Abstract
Enzymatic degradation of polyethylene terephthalic acid (PET) has been gaining increasing importance. This has resulted in a significant increase in the search for newer enzymes and the development of more efficient enzyme-based systems. Due to the lack of a standard screening process, screening new enzymes has relied on other assays to determine the presence of esterase activity. This, in turn, has led to various nomenclatures and methods used to describe them and measure their activity. Since all PET-hydrolyzing enzymes are α/β hydrolases, they catalyze a serine nucleophilic attack and cleave an ester bond. They are lipases, esterases, cutinases and hydrolases. This has been used interchangeably, leading to difficulties while comparing results and evaluating progress. This review discusses the varied enzyme nomenclature being adapted, the different assays and analysis methods reported, and the strategies used to increase PET-hydrolyzing enzyme efficiency. A section on the various ways to quantify PET hydrolysis is also covered.
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Affiliation(s)
- Ruth Amanna
- Department of Biotechnology, Lakehead University, Thunder Bay, ON, Canada
- Biorefining Research Institute (BRI), Lakehead University, Thunder Bay, ON, Canada
| | - Sudip K Rakshit
- Department of Biotechnology, Lakehead University, Thunder Bay, ON, Canada.
- Biorefining Research Institute (BRI), Lakehead University, Thunder Bay, ON, Canada.
- Department of Chemical Engineering, Lakehead University, Thunder Bay, ON, Canada.
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3
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Orr G, Niv Y, Barakat M, Boginya A, Dessau M, Afriat-Jurnou L. Streamlined screening of extracellularly expressed PETase libraries for improved polyethylene terephthalate degradation. Biotechnol J 2024; 19:e2400021. [PMID: 38987219 DOI: 10.1002/biot.202400021] [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: 01/09/2024] [Revised: 05/26/2024] [Accepted: 06/03/2024] [Indexed: 07/12/2024]
Abstract
Enzyme-mediated polyethylene terephthalate (PET) depolymerization has recently emerged as a sustainable solution for PET recycling. Towards an industrial-scale implementation of this technology, various strategies are being explored to enhance PET depolymerization (PETase) activity and improve enzyme stability, expression, and purification processes. Recently, rational engineering of a known PET hydrolase (LCC-leaf compost cutinase) has resulted in the isolation of a variant harboring four-point mutations (LCC-ICCG), presenting increased PETase activity and thermal stability. Here, we revealed the enzyme's natural extracellular expression and used it to efficiently screen error-prone genetic libraries based on LCC-ICCG for enhanced activity toward consumer-grade PET. Following multiple rounds of mutagenesis and screening, we successfully isolated variants that exhibited up to a 60% increase in PETase activity. Among other mutations, the improved variants showed a histidine to tyrosine substitution at position 218, a residue known to be involved in substrate binding and stabilization. Introducing H218Y mutation on the background of LCC-ICCG (named here LCC-ICCG/H218Y) resulted in a similar level of activity improvement. Analysis of the solved structure of LCC-ICCG/H218Y compared to other known PETases featuring different amino acids at the equivalent position suggests that H218Y substitution promotes enhanced PETase activity. The expression and screening processes developed in this study can be further used to optimize additional enzymatic parameters crucial for efficient enzymatic degradation of consumer-grade PET.
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Affiliation(s)
- Guy Orr
- Migal-Galilee Research Institute, Kiryat Shmona, Israel
| | - Yoav Niv
- Migal-Galilee Research Institute, Kiryat Shmona, Israel
| | - Maya Barakat
- The Azrieli Faculty of Medicine, Bar Ilan University, Safed, Israel
| | | | - Moshe Dessau
- The Azrieli Faculty of Medicine, Bar Ilan University, Safed, Israel
| | - Livnat Afriat-Jurnou
- Migal-Galilee Research Institute, Kiryat Shmona, Israel
- Faculty of Sciences and Technology, Tel-Hai Academic College, Upper Galilee, Israel
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Yang J, Li Z, Xu Q, Liu W, Gao S, Qin P, Chen Z, Wang A. Towards carbon neutrality: Sustainable recycling and upcycling strategies and mechanisms for polyethylene terephthalate via biotic/abiotic pathways. ECO-ENVIRONMENT & HEALTH 2024; 3:117-130. [PMID: 38638172 PMCID: PMC11021832 DOI: 10.1016/j.eehl.2024.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 01/09/2024] [Accepted: 01/25/2024] [Indexed: 04/20/2024]
Abstract
Polyethylene terephthalate (PET), one of the most ubiquitous engineering plastics, presents both environmental challenges and opportunities for carbon neutrality and a circular economy. This review comprehensively addressed the latest developments in biotic and abiotic approaches for PET recycling/upcycling. Biotically, microbial depolymerization of PET, along with the biosynthesis of reclaimed monomers [terephthalic acid (TPA), ethylene glycol (EG)] to value-added products, presents an alternative for managing PET waste and enables CO2 reduction. Abiotically, thermal treatments (i.e., hydrolysis, glycolysis, methanolysis, etc.) and photo/electrocatalysis, enabled by catalysis advances, can depolymerize or convert PET/PET monomers in a more flexible, simple, fast, and controllable manner. Tandem abiotic/biotic catalysis offers great potential for PET upcycling to generate commodity chemicals and alternative materials, ideally at lower energy inputs, greenhouse gas emissions, and costs, compared to virgin polymer fabrication. Remarkably, over 25 types of upgraded PET products (e.g., adipic acid, muconic acid, catechol, vanillin, and glycolic acid, etc.) have been identified, underscoring the potential of PET upcycling in diverse applications. Efforts can be made to develop chemo-catalytic depolymerization of PET, improve microbial depolymerization of PET (e.g., hydrolysis efficiency, enzymatic activity, thermal and pH level stability, etc.), as well as identify new microorganisms or hydrolases capable of degrading PET through computational and machine learning algorithms. Consequently, this review provides a roadmap for advancing PET recycling and upcycling technologies, which hold the potential to shape the future of PET waste management and contribute to the preservation of our ecosystems.
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Affiliation(s)
- Jiaqi Yang
- School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Zhiling Li
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qiongying Xu
- School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Wenzong Liu
- School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Shuhong Gao
- School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Peiwu Qin
- Institute of Biopharmaceutical and Health Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Tsinghua-Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Zhenglin Chen
- Institute of Biopharmaceutical and Health Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Tsinghua-Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Aijie Wang
- School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
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Peña-Montes C, Bermúdez-García E, Castro-Ochoa D, Vega-Pérez F, Esqueda-Domínguez K, Castro-Rodríguez JA, González-Canto A, Segoviano-Reyes L, Navarro-Ocaña A, Farrés A. ANCUT1, a novel thermoalkaline cutinase from Aspergillus nidulans and its application on hydroxycinnamic acids lipophilization. Biotechnol Lett 2024; 46:409-430. [PMID: 38416309 PMCID: PMC11055803 DOI: 10.1007/s10529-024-03467-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/17/2023] [Accepted: 01/08/2024] [Indexed: 02/29/2024]
Abstract
One of the four cutinases encoded in the Aspergillus nidulans genome, ANCUT1, is described here. Culture conditions were evaluated, and it was found that this enzyme is produced only when cutin is present in the culture medium, unlike the previously described ANCUT2, with which it shares 62% amino acid identity. The differences between them include the fact that ANCUT1 is a smaller enzyme, with experimental molecular weight and pI values of 22 kDa and 6, respectively. It shows maximum activity at pH 9 and 60 °C under assayed conditions and retains more than 60% of activity after incubation for 1 h at 60 °C in a wide range of pH values (6-10) after incubations of 1 or 3 h. It has a higher activity towards medium-chain esters and can modify long-chain length hydroxylated fatty acids constituting cutin. Its substrate specificity properties allow the lipophilization of alkyl coumarates, valuable antioxidants and its thermoalkaline behavior, which competes favorably with other fungal cutinases, suggests it may be useful in many more applications.
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Affiliation(s)
- Carolina Peña-Montes
- Tecnológico Nacional de México/IT Veracruz, Unidad de Investigación y Desarrollo en Alimentos (UNIDA), Calzada Miguel Angel de Quevedo, 2779. Col. Formando Hogar, Veracruz, México, CP 91897
| | - Eva Bermúdez-García
- Departamento de Alimentos y Biotecnología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP 04510, Ciudad de México, Mexico
| | - Denise Castro-Ochoa
- Tecnológico Nacional de México/IT Mochis, Juan de Dios Batiz y 20 de Noviembre, CP 81259, Los Mochis, Sinaloa, Mexico
| | - Fernanda Vega-Pérez
- Departamento de Alimentos y Biotecnología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP 04510, Ciudad de México, Mexico
| | - Katia Esqueda-Domínguez
- Departamento de Alimentos y Biotecnología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP 04510, Ciudad de México, Mexico
| | - José Augusto Castro-Rodríguez
- Departamento de Alimentos y Biotecnología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP 04510, Ciudad de México, Mexico
| | - Augusto González-Canto
- Unidad de Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Hospital General de México, Dr. Balmis, 148, CP 06726, Ciudad de México, Mexico
| | - Laura Segoviano-Reyes
- Departamento de Alimentos y Biotecnología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP 04510, Ciudad de México, Mexico
| | - Arturo Navarro-Ocaña
- Departamento de Alimentos y Biotecnología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP 04510, Ciudad de México, Mexico
| | - Amelia Farrés
- Departamento de Alimentos y Biotecnología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, CP 04510, Ciudad de México, Mexico.
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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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Schreiber S, Gercke D, Lenz F, Jose J. Application of an alchemical free energy method for the prediction of thermostable DuraPETase variants. Appl Microbiol Biotechnol 2024; 108:305. [PMID: 38643427 PMCID: PMC11033240 DOI: 10.1007/s00253-024-13144-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/25/2024] [Accepted: 04/09/2024] [Indexed: 04/22/2024]
Abstract
Non-equilibrium (NEQ) alchemical free energy calculations are an emerging tool for accurately predicting changes in protein folding free energy resulting from amino acid mutations. In this study, this method in combination with the Rosetta ddg monomer tool was applied to predict more thermostable variants of the polyethylene terephthalate (PET) degrading enzyme DuraPETase. The Rosetta ddg monomer tool efficiently enriched promising mutations prior to more accurate prediction by NEQ alchemical free energy calculations. The relative change in folding free energy of 96 single amino acid mutations was calculated by NEQ alchemical free energy calculation. Experimental validation of ten of the highest scoring variants identified two mutations (DuraPETaseS61M and DuraPETaseS223Y) that increased the melting temperature (Tm) of the enzyme by up to 1 °C. The calculated relative change in folding free energy showed an excellent correlation with experimentally determined Tm resulting in a Pearson's correlation coefficient of r = - 0.84. Limitations in the prediction of strongly stabilizing mutations were, however, encountered and are discussed. Despite these challenges, this study demonstrates the practical applicability of NEQ alchemical free energy calculations in prospective enzyme engineering projects. KEY POINTS: • Rosetta ddg monomer enriches stabilizing mutations in a library of DuraPETase variants • NEQ free energy calculations accurately predict changes in Tm of DuraPETase • The DuraPETase variants S223Y, S42M, and S61M have increased Tm.
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Affiliation(s)
- Sebastian Schreiber
- University of Münster, Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus, Corrensstr. 48, 48149, Münster, Germany
| | - David Gercke
- University of Münster, Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus, Corrensstr. 48, 48149, Münster, Germany
| | - Florian Lenz
- University of Münster, Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus, Corrensstr. 48, 48149, Münster, Germany
| | - Joachim Jose
- University of Münster, Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus, Corrensstr. 48, 48149, Münster, Germany.
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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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Naidu G, Nagar N, Poluri KM. Mechanistic Insights into Cellular and Molecular Basis of Protein-Nanoplastic Interactions. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2305094. [PMID: 37786309 DOI: 10.1002/smll.202305094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 09/07/2023] [Indexed: 10/04/2023]
Abstract
Plastic waste is ubiquitously present across the world, and its nano/sub-micron analogues (plastic nanoparticles, PNPs), raise severe environmental concerns affecting organisms' health. Considering the direct and indirect toxic implications of PNPs, their biological impacts are actively being studied; lately, with special emphasis on cellular and molecular mechanistic intricacies. Combinatorial OMICS studies identified proteins as major regulators of PNP mediated cellular toxicity via activation of oxidative enzymes and generation of ROS. Alteration of protein function by PNPs results in DNA damage, organellar dysfunction, and autophagy, thus resulting in inflammation/cell death. The molecular mechanistic basis of these cellular toxic endeavors is fine-tuned at the level of structural alterations in proteins of physiological relevance. Detailed biophysical studies on such protein-PNP interactions evidenced prominent modifications in their structural architecture and conformational energy landscape. Another essential aspect of the protein-PNP interactions includes bioenzymatic plastic degradation perspective, as the interactive units of plastics are essentially nano-sized. Combining all these attributes of protein-PNP interactions, the current review comprehensively documented the contemporary understanding of the concerned interactions in the light of cellular, molecular, kinetic/thermodynamic details. Additionally, the applicatory, economical facet of these interactions, PNP biogeochemical cycle and enzymatic advances pertaining to plastic degradation has also been discussed.
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Affiliation(s)
- Goutami Naidu
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Nupur Nagar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Krishna Mohan Poluri
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
- Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
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Joho Y, Vongsouthi V, Gomez C, Larsen JS, Ardevol A, Jackson CJ. Improving plastic degrading enzymes via directed evolution. Protein Eng Des Sel 2024; 37:gzae009. [PMID: 38713696 PMCID: PMC11091475 DOI: 10.1093/protein/gzae009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 04/30/2024] [Accepted: 05/05/2024] [Indexed: 05/09/2024] Open
Abstract
Plastic degrading enzymes have immense potential for use in industrial applications. Protein engineering efforts over the last decade have resulted in considerable enhancement of many properties of these enzymes. Directed evolution, a protein engineering approach that mimics the natural process of evolution in a laboratory, has been particularly useful in overcoming some of the challenges of structure-based protein engineering. For example, directed evolution has been used to improve the catalytic activity and thermostability of polyethylene terephthalate (PET)-degrading enzymes, although its use for the improvement of other desirable properties, such as solvent tolerance, has been less studied. In this review, we aim to identify some of the knowledge gaps and current challenges, and highlight recent studies related to the directed evolution of plastic-degrading enzymes.
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Affiliation(s)
- Yvonne Joho
- Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Research Way, Clayton, Victoria 3168, Australia
- Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
- CSIRO Advanced Engineering Biology Future Science Platform, GPO Box 1700, Canberra, ACT 2601, Australia
| | - Vanessa Vongsouthi
- Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
| | - Chloe Gomez
- Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
| | - Joachim S Larsen
- Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
- ARC Centre of Excellence for Synthetic Biology, Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
| | - Albert Ardevol
- Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Research Way, Clayton, Victoria 3168, Australia
- CSIRO Advanced Engineering Biology Future Science Platform, GPO Box 1700, Canberra, ACT 2601, Australia
| | - Colin J Jackson
- Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
- ARC Centre of Excellence for Synthetic Biology, Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
- ARC Centre of Excellence for Innovations in Peptide & Protein Science, Research School of Chemistry, Australian National University, Sullivans Creek Rd, Canberra, ACT 2601, Australia
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11
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Shi L, Zhu L. Recent Advances and Challenges in Enzymatic Depolymerization and Recycling of PET Wastes. Chembiochem 2024; 25:e202300578. [PMID: 37960968 DOI: 10.1002/cbic.202300578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 11/12/2023] [Accepted: 11/13/2023] [Indexed: 11/15/2023]
Abstract
Poly (ethylene terephthalate) (PET) is one of the most commonly used plastics in daily life and various industries. Enzymatic depolymerization and recycling of post-consumer PET (pc-PET) provides a promising strategy for the sustainable circular economy of polymers. Great protein engineering efforts have been devoted to improving the depolymerization performance of PET hydrolytic enzymes (PHEs). In this review, we first discuss the mechanisms and challenges of enzymatic PET depolymerization. Subsequently, we summarize the state-of-the-art engineering of PHEs including rational design, machine learning, and directed evolution for improved depolymerization performance, and highlight the advances in screening methods of PHEs. We further discuss several factors that affect the enzymatic depolymerization efficiency. We conclude with our perspective on the opportunities and challenges in bio-recycling and bio-upcycling of PET wastes.
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Affiliation(s)
- Lixia Shi
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
| | - Leilei Zhu
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China
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12
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Qiu J, Chen Y, Zhang L, Wu J, Zeng X, Shi X, Liu L, Chen J. A comprehensive review on enzymatic biodegradation of polyethylene terephthalate. ENVIRONMENTAL RESEARCH 2024; 240:117427. [PMID: 37865324 DOI: 10.1016/j.envres.2023.117427] [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: 08/28/2023] [Revised: 10/11/2023] [Accepted: 10/15/2023] [Indexed: 10/23/2023]
Abstract
Polyethylene terephthalate (PET) is a polymer synthesized via the dehydration and condensation reaction between ethylene glycol and terephthalic acid. PET has emerged as one of the most extensively employed plastic materials due to its exceptional plasticity and durability. Nevertheless, PET has a complex structure and is extremely difficult to degrade in nature, causing severe pollution to the global ecological environment and posing a threat to human health. Currently, the methods for PET processing mainly include physical, chemical, and biological methods. Biological enzyme degradation is considered the most promising PET degradation method. In recent years, an increasing number of enzymes that can degrade PET have been identified, and they primarily target the ester bond of PET. This review comprehensively introduced the latest research progress in PET enzymatic degradation from the aspects of PET-degrading enzymes, PET biodegradation pathways, the catalytic mechanism of PET-degrading enzymes, and biotechnological strategies for enhancing PET-degrading enzymes. On this basis, the current challenges within the enzymatic PET degradation process were summarized, and the directions that need to be worked on in the future were pointed out. This review provides a reference and basis for the subsequent effective research on PET biodegradation.
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Affiliation(s)
- Jiarong Qiu
- School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China; Development Center of Science and Education Park of Fuzhou University, Jinjiang, 362251, China
| | - Yuxin Chen
- School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
| | - Liangqing Zhang
- School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China; Development Center of Science and Education Park of Fuzhou University, Jinjiang, 362251, China.
| | - Jinzhi Wu
- School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
| | - Xianhai Zeng
- College of Energy, Xiamen University, Xiamen 361102, China
| | - Xinguo Shi
- School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
| | - Lemian Liu
- School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
| | - Jianfeng Chen
- School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
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13
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Buhari SB, Nezhad NG, Normi YM, Shariff FM, Leow TC. Insight on recently discovered PET polyester-degrading enzymes, thermostability and activity analyses. 3 Biotech 2024; 14:31. [PMID: 38178895 PMCID: PMC10761646 DOI: 10.1007/s13205-023-03882-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 12/05/2023] [Indexed: 01/06/2024] Open
Abstract
The flexibility and the low production costs offered by plastics have made them crucial to society. Unfortunately, due to their resistance to biological degradation, plastics remain in the environment for an extended period of time, posing a growing risk to life on earth. Synthetic treatments of plastic waste damage the environment and may cause damage to human health. Bacterial and fungal isolates have been reported to degrade plastic polymers in a logistic safe approach with the help of their microbial cell enzymes. Recently, the bacterial strain Ideonella sakaiensis (201-F6) was discovered to break down and assimilate polyethylene terephthalate (PET) plastic via metabolic processes at 30 °C to 37 °C. PETase and MHETase enzymes help the bacterium to accomplish such tremendous action at lower temperatures than previously discovered enzymes. In addition to functioning at low temperatures, the noble bacterium's enzymes have amazing qualities over pH and PET plastic degradation, including a shorter period of degradation. It has been proven that using the enzyme PETase, this bacterium hydrolyzes the ester linkages of PET plastic, resulting in production of terephthalic acid (TPA), nontoxic compound and mono-2-hydroxyethyl (MHET), along with further depolymerization of MHET to release ethylene glycogen (EG) and terephthalic acid (TPA) by the second enzyme MHETase. Enzymatic plastic degradation has been proposed as an environmentally friendly and long-term solution to plastic waste in the environment. As a result, this review focuses on the enzymes involved in hydrolyzing PET plastic polymers, as well as some of the other microorganisms involved in plastic degradation.
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Affiliation(s)
- Sunusi Bataiya Buhari
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
| | - Nima Ghahremani Nezhad
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
| | - Yahaya M. Normi
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
| | - Fairolniza Mohd Shariff
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
| | - Thean Chor Leow
- Enzyme and Microbial Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Malaysia
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14
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Cao Z, Xia W, Wu S, Ma J, Zhou X, Qian X, Xu A, Dong W, Jiang M. Bioengineering Comamonas testosteroni CNB-1: a robust whole-cell biocatalyst for efficient PET microplastic degradation. BIORESOUR BIOPROCESS 2023; 10:94. [PMID: 38647778 PMCID: PMC10992048 DOI: 10.1186/s40643-023-00715-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 12/10/2023] [Indexed: 04/25/2024] Open
Abstract
The escalating crisis of polyethylene terephthalate (PET) microplastic contamination in biological wastewater treatment systems is a pressing environmental concern. These microplastics inevitably accumulate in sewage sludge due to the absence of effective removal technologies. Addressing this urgent issue, this study introduces a novel approach using DuraPETase, a potent enzyme with enhanced PET hydrolytic activity at ambient temperatures. Remarkably, this enzyme was successfully secreted from Comamonas testosteroni CNB-1, a dominant species in the active sludge. The secreted DuraPETase showed significant hydrolytic activity toward p-NPB and PET nanoplastics. Furthermore, the CNB-1 derived whole-cell biocatalyst was able to depolymerize PET microplastics under ambient temperature, achieving a degradation efficiency of 9% within 7 days. The CNB-1-based whole biocatalysts were also capable of utilizing PET degradation intermediates, such as terephthalic acid (TPA) and ethylene glycol (EG), and bis(2-hydroxyethyl)-TPA (BHET), for growth. This indicates that it can completely mineralize PET, as opposed to merely breaking it down into smaller molecules. This research highlights the potential of activated sludge as a potent source for insitu microplastic removal.
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Affiliation(s)
- Zhanqing Cao
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Wei Xia
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Shilei Wu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Jiale Ma
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Xiaoli Zhou
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Xiujuan Qian
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Anming Xu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China.
| | - Weiliang Dong
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China.
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China.
- Key Laboratory for Waste Plastics Biocatalytic Degradation and Recycling, Nanjing Tech University, Nanjing, 211816, China.
| | - Min Jiang
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China
- Key Laboratory for Waste Plastics Biocatalytic Degradation and Recycling, Nanjing Tech University, Nanjing, 211816, China
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15
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Soong YHV, Abid U, Chang AC, Ayafor C, Patel A, Qin J, Xu J, Lawton C, Wong HW, Sobkowicz MJ, Xie D. Enzyme selection, optimization, and production toward biodegradation of post-consumer poly(ethylene terephthalate) at scale. Biotechnol J 2023; 18:e2300119. [PMID: 37594123 DOI: 10.1002/biot.202300119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 08/07/2023] [Accepted: 08/11/2023] [Indexed: 08/19/2023]
Abstract
Poly(ethylene terephthalate) (PET) is one of the world's most widely used polyester plastics. Due to its chemical stability, PET is extremely difficult to hydrolyze in a natural environment. Recent discoveries in new polyester hydrolases and breakthroughs in enzyme engineering strategies have inspired enormous research on biorecycling of PET. This study summarizes our research efforts toward large-scale, efficient, and economical biodegradation of post-consumer waste PET, including PET hydrolase selection and optimization, high-yield enzyme production, and high-capacity enzymatic degradation of post-consumer waste PET. First, genes encoding PETase and MHETase from Ideonella sakaiensis and the ICCG variant of leaf-branch compost cutinase (LCCICCG ) were codon-optimized and expressed in Escherichia coli BL21(DE3) for high-yield production. To further lower the enzyme production cost, a pelB leader sequence was fused to LCCICCG so that the enzyme can be secreted into the medium to facilitate recovery. To help bind the enzyme on the hydrophobic surface of PET, a substrate-binding module in a polyhydroxyalkanoate depolymerase from Alcaligenes faecalis (PBM) was fused to the C-terminus of LCCICCG . The resulting four different LCCICCG variants (LCC, PelB-LCC, LCC-PBM, and PelB-LCC-PBM), together with PETase and MHETase, were compared for PET degradation efficiency. A fed-batch fermentation process was developed to produce the target enzymes up to 1.2 g L-1 . Finally, the best enzyme, PelB-LCC, was selected and used for the efficient degradation of 200 g L-1 recycled PET in a well-controlled, stirred-tank reactor. The results will help develop an economical and scalable biorecycling process toward a circular PET economy.
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Affiliation(s)
- Ya-Hue Valerie Soong
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Umer Abid
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Allen C Chang
- Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Christian Ayafor
- Energy Engineering Program, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Akanksha Patel
- Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Jiansong Qin
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Jin Xu
- Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Carl Lawton
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Hsi-Wu Wong
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Margaret J Sobkowicz
- Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Dongming Xie
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
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16
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Zhang J, Wang H, Luo Z, Yang Z, Zhang Z, Wang P, Li M, Zhang Y, Feng Y, Lu D, Zhu Y. Computational design of highly efficient thermostable MHET hydrolases and dual enzyme system for PET recycling. Commun Biol 2023; 6:1135. [PMID: 37945666 PMCID: PMC10636135 DOI: 10.1038/s42003-023-05523-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023] Open
Abstract
Recently developed enzymes for the depolymerization of polyethylene terephthalate (PET) such as FAST-PETase and LCC-ICCG are inhibited by the intermediate PET product mono(2-hydroxyethyl) terephthalate (MHET). Consequently, the conversion of PET enzymatically into its constituent monomers terephthalic acid (TPA) and ethylene glycol (EG) is inefficient. In this study, a protein scaffold (1TQH) corresponding to a thermophilic carboxylesterase (Est30) was selected from the structural database and redesigned in silico. Among designs, a double variant KL-MHETase (I171K/G130L) with a similar protein melting temperature (67.58 °C) to that of the PET hydrolase FAST-PETase (67.80 °C) exhibited a 67-fold higher activity for MHET hydrolysis than FAST-PETase. A fused dual enzyme system comprising KL-MHETase and FAST-PETase exhibited a 2.6-fold faster PET depolymerization rate than FAST-PETase alone. Synergy increased the yield of TPA by 1.64 fold, and its purity in the released aromatic products reached 99.5%. In large reaction systems with 100 g/L substrate concentrations, the dual enzyme system KL36F achieved over 90% PET depolymerization into monomers, demonstrating its potential applicability in the industrial recycling of PET plastics. Therefore, a dual enzyme system can greatly reduce the reaction and separation cost for sustainable enzymatic PET recycling.
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Affiliation(s)
- Jun Zhang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
- Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China
| | - Hongzhao Wang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Zhaorong Luo
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Zhenwu Yang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Zixuan Zhang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Pengyu Wang
- Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China
| | - Mengyu Li
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yi Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yue Feng
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Diannan Lu
- Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China.
| | - Yushan Zhu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
- National Energy R&D Center for Biorefinery, Beijing University of Chemical Technology, Beijing, 100029, China.
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17
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Howard SA, McCarthy RR. Modulating biofilm can potentiate activity of novel plastic-degrading enzymes. NPJ Biofilms Microbiomes 2023; 9:72. [PMID: 37788986 PMCID: PMC10547765 DOI: 10.1038/s41522-023-00440-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 09/19/2023] [Indexed: 10/05/2023] Open
Abstract
Plastic pollution is an increasing global issue desperately requiring a solution. Only 9% of all plastic waste has been recycled, and whilst recycling gives a second life to plastic, it is costly and there are limited downstream uses of recycled plastic, therefore an alternative is urgently needed. Biodegradation of plastic by microorganisms is a developing field of interest with the potential for bioreactors to be used alongside recycling to degrade plastic that may otherwise be sent to landfill. Here, we have identified two novel polyethylene terephthalate (PET) degrading enzymes through genomic mining and characterised their activity, including their ability to degrade PET. One of the main roadblocks facing the development of microbial enzymes as a plastic biodegradation solution, is that their efficiency is too low to facilitate development as bioremediation tools. In an innovative approach to tackle this roadblock, we hypothesised that enhancing a bacteria's ability to attach to and form a biofilm on plastic could maximise the local concentration of the enzyme around the target substrate, therefore increasing the overall rate of plastic degradation. We found that increasing biofilm levels, by manipulating the levels of the second messenger, Cyclic-di-GMP, led to increased levels of polyester degradation in cells expressing novel and well characterised polyester-degrading enzymes. This indicates that modulating biofilm formation is a viable mechanism to fast track the development of bacterial plastic bioremediation solutions.
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Affiliation(s)
- Sophie A Howard
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Ronan R McCarthy
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK.
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18
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Duan S, Zhang N, Chao T, Wu Y, Wang M. The structural and molecular mechanisms of type II PETases: a mini review. Biotechnol Lett 2023; 45:1249-1263. [PMID: 37535135 DOI: 10.1007/s10529-023-03418-3] [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: 03/21/2023] [Accepted: 07/15/2023] [Indexed: 08/04/2023]
Abstract
The advent of plastics has led to significant advances for humans, although the accompanying pollution has also been a source of concern for countries globally. Consequently, a biological method to effectively degrade polyethylene terephthalate (PET) has been an area of significant scientific interest. Following the report of the highly efficient PET hydrolase from the bacterium Ideonella sakaiensis strain 201-F6 (i.e., IsPETase) in 2016, its structure has been extensively studied, showing that it belongs to the type II PETase group. Unlike type I PETases that include most known cutinases, structural investigations of type II PETases have only been conducted since 2017. Type II PETases are further divided into type IIa and IIb enzymes. Moreover, even less research has been conducted on type IIa plastic-degrading enzymes. Here, we present a review of recent studies of the structure and mechanism of type II PETases, using the known structure of the type IIa PETase PE-H from the marine bacterium Pseudomonas aestusnigri in addition to the type IIb enzyme IsPETase as representatives. These studies have provided new insights into the structural features of type II PETases that exhibit PET catalytic activity. In addition, recent studies investigating the rational design of IsPETases are reviewed and summarized alongside a discussion of controversies surrounding PETase investigations.
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Affiliation(s)
- Shuyan Duan
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang, 277160, Shandong, China.
| | - Nan Zhang
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang, 277160, Shandong, China
| | - Tianzhu Chao
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang, 277160, Shandong, China
| | - Yaoyao Wu
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang, 277160, Shandong, China
| | - Mengying Wang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, Guangdong, China.
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19
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Liu F, Wang T, Yang W, Zhang Y, Gong Y, Fan X, Wang G, Lu Z, Wang J. Current advances in the structural biology and molecular engineering of PETase. Front Bioeng Biotechnol 2023; 11:1263996. [PMID: 37795175 PMCID: PMC10546322 DOI: 10.3389/fbioe.2023.1263996] [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: 07/20/2023] [Accepted: 08/31/2023] [Indexed: 10/06/2023] Open
Abstract
Poly(ethylene terephthalate) (PET) is a highly useful synthetic polyester plastic that is widely used in daily life. However, the increase in postconsumer PET as plastic waste that is recalcitrant to biodegradation in landfills and the natural environment has raised worldwide concern. Currently, traditional PET recycling processes with thermomechanical or chemical methods also result in the deterioration of the mechanical properties of PET. Therefore, it is urgent to develop more efficient and green strategies to address this problem. Recently, a novel mesophilic PET-degrading enzyme (IsPETase) from Ideonella sakaiensis was found to streamline PET biodegradation at 30°C, albeit with a lower PET-degrading activity than chitinase or chitinase-like PET-degrading enzymes. Consequently, the molecular engineering of more efficient PETases is still required for further industrial applications. This review details current knowledge on IsPETase, MHETase, and IsPETase-like hydrolases, including the structures, ligand‒protein interactions, and rational protein engineering for improved PET-degrading performance. In particular, applications of the engineered catalysts are highlighted, including metabolic engineering of the cell factories, enzyme immobilization or cell surface display. The information is expected to provide novel insights for the biodegradation of complex polymers.
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Affiliation(s)
- Fei Liu
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Tao Wang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Wentao Yang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Yingkang Zhang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Yuming Gong
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Xinxin Fan
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Guocheng Wang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Zhenhua Lu
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jianmin Wang
- School of Pharmacy, Jining Medical University, Rizhao, China
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20
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Williams GB, Ma H, Khusnutdinova AN, Yakunin AF, Golyshin PN. Harnessing extremophilic carboxylesterases for applications in polyester depolymerisation and plastic waste recycling. Essays Biochem 2023; 67:715-729. [PMID: 37334661 PMCID: PMC10423841 DOI: 10.1042/ebc20220255] [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: 03/19/2023] [Revised: 06/01/2023] [Accepted: 06/05/2023] [Indexed: 06/20/2023]
Abstract
The steady growth in industrial production of synthetic plastics and their limited recycling have resulted in severe environmental pollution and contribute to global warming and oil depletion. Currently, there is an urgent need to develop efficient plastic recycling technologies to prevent further environmental pollution and recover chemical feedstocks for polymer re-synthesis and upcycling in a circular economy. Enzymatic depolymerization of synthetic polyesters by microbial carboxylesterases provides an attractive addition to existing mechanical and chemical recycling technologies due to enzyme specificity, low energy consumption, and mild reaction conditions. Carboxylesterases constitute a diverse group of serine-dependent hydrolases catalysing the cleavage and formation of ester bonds. However, the stability and hydrolytic activity of identified natural esterases towards synthetic polyesters are usually insufficient for applications in industrial polyester recycling. This necessitates further efforts on the discovery of robust enzymes, as well as protein engineering of natural enzymes for enhanced activity and stability. In this essay, we discuss the current knowledge of microbial carboxylesterases that degrade polyesters (polyesterases) with focus on polyethylene terephthalate (PET), which is one of the five major synthetic polymers. Then, we briefly review the recent progress in the discovery and protein engineering of microbial polyesterases, as well as developing enzyme cocktails and secreted protein expression for applications in the depolymerisation of polyester blends and mixed plastics. Future research aimed at the discovery of novel polyesterases from extreme environments and protein engineering for improved performance will aid developing efficient polyester recycling technologies for the circular plastics economy.
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Affiliation(s)
- Gwion B Williams
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Road, Bangor LL57 2UW, U.K
| | - Hairong Ma
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Road, Bangor LL57 2UW, U.K
| | - Anna N Khusnutdinova
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Road, Bangor LL57 2UW, U.K
| | - Alexander F Yakunin
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Road, Bangor LL57 2UW, U.K
| | - Peter N Golyshin
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Road, Bangor LL57 2UW, U.K
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21
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Chen L, Fan F, Yang M, Wang L, Bai Y, Qiu S, Lyu C, Huang J. Atomistic insight into the binding mode and self-regulation mechanism of IsPETase towards PET substrates with different polymerization degrees. Phys Chem Chem Phys 2023. [PMID: 37401198 DOI: 10.1039/d3cp01700a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2023]
Abstract
Poly(ethylene terephthalate) (PET) is one of the most widely used synthetic polyesters, however, its extensive use creates a long-term environmental burden. Unlike traditional recycling methods, biodegradation is a sustainable strategy. The emergence of PETase from Ideonella sakaiensis 201-F6 (IsPETase) has brought great potential for the industrialization of degradable PET. In this work, models of enzyme-substrate complexes with different degrees of polymerization were established to study the binding mode using molecular dynamics simulation. We found that the whole binding site can be further subdivided into three parts, including head, middle and tail binding regions. Most importantly, the presence of the middle region formed by both ends of Ser93 and Ser236 provides a potential possibility for the binding of substrates with different chain lengths, and exerts the self-regulation ability of enzymes to accommodate substrates. Meanwhile, the 'pocket bottom' Arg280 in the tail region echoes the 'pocket mouth' Trp185 in the head region, defining the substrate binding region. This work reveals the self-regulation of IsPETase, as well as the key residues for the substrate binding. The solution to these problems enables us to better understand the function of enzymes and design high-performance degradation enzymes, which is of great significance for industrial application research.
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Affiliation(s)
- Linyu Chen
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
| | - Fangfang Fan
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 360015, P. R. China
| | - Meiyuan Yang
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
| | - Linquan Wang
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
| | - Yushuo Bai
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
| | - Shuai Qiu
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
| | - Changjiang Lyu
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
| | - Jun Huang
- Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province, Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, P. R. China.
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22
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Fransen KA, Av-Ron SHM, Buchanan TR, Walsh DJ, Rota DT, Van Note L, Olsen BD. High-throughput experimentation for discovery of biodegradable polyesters. Proc Natl Acad Sci U S A 2023; 120:e2220021120. [PMID: 37252959 PMCID: PMC10266013 DOI: 10.1073/pnas.2220021120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Accepted: 03/08/2023] [Indexed: 06/01/2023] Open
Abstract
The consistent rise of plastic pollution has stimulated interest in the development of biodegradable plastics. However, the study of polymer biodegradation has historically been limited to a small number of polymers due to costly and slow standard methods for measuring degradation, slowing new material innovation. High-throughput polymer synthesis and a high-throughput polymer biodegradation method are developed and applied to generate a biodegradation dataset for 642 chemically distinct polyesters and polycarbonates. The biodegradation assay was based on the clear-zone technique, using automation to optically observe the degradation of suspended polymer particles under the action of a single Pseudomonas lemoignei bacterial colony. Biodegradability was found to depend strongly on aliphatic repeat unit length, with chains less than 15 carbons and short side chains improving biodegradability. Aromatic backbone groups were generally detrimental to biodegradability; however, ortho- and para-substituted benzene rings in the backbone were more likely to be degradable than metasubstituted rings. Additionally, backbone ether groups improved biodegradability. While other heteroatoms did not show a clear improvement in biodegradability, they did demonstrate increases in biodegradation rates. Machine learning (ML) models were leveraged to predict biodegradability on this large dataset with accuracies over 82% using only chemical structure descriptors.
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Affiliation(s)
- Katharina A. Fransen
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Sarah H. M. Av-Ron
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Tess R. Buchanan
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Dylan J. Walsh
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Dechen T. Rota
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Lana Van Note
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Bradley D. Olsen
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
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23
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Carr CM, Keller MB, Paul B, Schubert SW, Clausen KSR, Jensen K, Clarke DJ, Westh P, Dobson ADW. Purification and biochemical characterization of SM14est, a PET-hydrolyzing enzyme from the marine sponge-derived Streptomyces sp. SM14. Front Microbiol 2023; 14:1170880. [PMID: 37250061 PMCID: PMC10213408 DOI: 10.3389/fmicb.2023.1170880] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/21/2023] [Indexed: 05/31/2023] Open
Abstract
The successful enzymatic degradation of polyester substrates has fueled worldwide investigation into the treatment of plastic waste using bio-based processes. Within this realm, marine-associated microorganisms have emerged as a promising source of polyester-degrading enzymes. In this work, we describe the hydrolysis of the synthetic polymer PET by SM14est, a polyesterase which was previously identified from Streptomyces sp. SM14, an isolate of the marine sponge Haliclona simulans. The PET hydrolase activity of purified SM14est was assessed using a suspension-based assay and subsequent analysis of reaction products by UV-spectrophotometry and RP-HPLC. SM14est displayed a preference for high salt conditions, with activity significantly increasing at sodium chloride concentrations from 100 mM up to 1,000 mM. The initial rate of PET hydrolysis by SM14est was determined to be 0.004 s-1 at 45°C, which was increased by 5-fold to 0.02 s-1 upon addition of 500 mM sodium chloride. Sequence alignment and structural comparison with known PET hydrolases, including the marine halophile PET6, and the highly efficient, thermophilic PHL7, revealed conserved features of interest. Based on this work, SM14est emerges as a useful enzyme that is more similar to key players in the area of PET hydrolysis, like PHL7 and IsPETase, than it is to its marine counterparts. Salt-tolerant polyesterases such as SM14est are potentially valuable in the biological degradation of plastic particles that readily contaminate marine ecosystems and industrial wastewaters.
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Affiliation(s)
- Clodagh M. Carr
- School of Microbiology, University College Cork, Cork, Ireland
- SSPC-SFI Research Centre for Pharmaceuticals, University College Cork, Cork, Ireland
| | - Malene B. Keller
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Bijoya Paul
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Sune W. Schubert
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Kristine S. R. Clausen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | | | - David J. Clarke
- School of Microbiology, University College Cork, Cork, Ireland
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Peter Westh
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Alan D. W. Dobson
- School of Microbiology, University College Cork, Cork, Ireland
- SSPC-SFI Research Centre for Pharmaceuticals, University College Cork, Cork, Ireland
- Environmental Research Institute, University College Cork, Cork, Ireland
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24
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Avilan L, Lichtenstein BR, König G, Zahn M, Allen MD, Oliveira L, Clark M, Bemmer V, Graham R, Austin HP, Dominick G, Johnson CW, Beckham GT, McGeehan JE, Pickford AR. Concentration-Dependent Inhibition of Mesophilic PETases on Poly(ethylene terephthalate) Can Be Eliminated by Enzyme Engineering. CHEMSUSCHEM 2023; 16:e202202277. [PMID: 36811288 DOI: 10.1002/cssc.202202277] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Enzyme-based depolymerization is a viable approach for recycling of poly(ethylene terephthalate) (PET). PETase from Ideonella sakaiensis (IsPETase) is capable of PET hydrolysis under mild conditions but suffers from concentration-dependent inhibition. In this study, this inhibition is found to be dependent on incubation time, the solution conditions, and PET surface area. Furthermore, this inhibition is evident in other mesophilic PET-degrading enzymes to varying degrees, independent of the level of PET depolymerization activity. The inhibition has no clear structural basis, but moderately thermostable IsPETase variants exhibit reduced inhibition, and the property is completely absent in the highly thermostable HotPETase, previously engineered by directed evolution, which simulations suggest results from reduced flexibility around the active site. This work highlights a limitation in applying natural mesophilic hydrolases for PET hydrolysis and reveals an unexpected positive outcome of engineering these enzymes for enhanced thermostability.
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Affiliation(s)
- Luisana Avilan
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Bruce R Lichtenstein
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Gerhard König
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Michael Zahn
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Mark D Allen
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Liliana Oliveira
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Matilda Clark
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Victoria Bemmer
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Rosie Graham
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Harry P Austin
- Institute of Biochemistry, Department of Biotechnology & Enzyme Catalysis, University of Greifswald, D-17487, Greifswald, Germany
| | - Graham Dominick
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, United States
| | - Christopher W Johnson
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, United States
| | - Gregg T Beckham
- BOTTLE Consortium, Golden, CO 80401, United States
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, United States
| | - John E McGeehan
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
| | - Andrew R Pickford
- Centre for Enzyme Innovation, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, United Kingdom
- BOTTLE Consortium, Golden, CO 80401, United States
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25
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Hellesnes KN, Vijayaraj S, Fojan P, Petersen E, Courtade G. Biochemical Characterization and NMR Study of a PET-Hydrolyzing Cutinase from Fusarium solani pisi. Biochemistry 2023; 62:1369-1375. [PMID: 36967526 PMCID: PMC10116592 DOI: 10.1021/acs.biochem.2c00619] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
In recent years, the drawbacks of plastics have become evident, with plastic pollution becoming a major environmental issue. There is an urgent need to find solutions to efficiently manage plastic waste by using novel recycling methods. Biocatalytic recycling of plastics by using enzyme-catalyzed hydrolysis is one such solution that has gained interest, in particular for recycling poly(ethylene terephthalate) (PET). To provide insights into PET hydrolysis by cutinases, we have here characterized the kinetics of a PET-hydrolyzing cutinase from Fusarium solani pisi (FsC) at different pH values, mapped the interaction between FsC and the PET analogue BHET by using NMR spectroscopy, and monitored product release directly and in real time by using time-resolved NMR experiments. We found that primarily aliphatic side chains around the active site participate in the interaction with BHET and that pH conditions and a mutation around the active site (L182A) can be used to tune the relative amounts of degradation products. Moreover, we propose that the low catalytic performance of FsC on PET is caused by poor substrate binding combined with slow MHET hydrolysis. Overall, our results provide insights into obstacles that preclude efficient PET hydrolysis by FsC and suggest future approaches for overcoming these obstacles and generating efficient PET-hydrolyzing enzymes.
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26
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Determinants for an Efficient Enzymatic Catalysis in Poly(Ethylene Terephthalate) Degradation. Catalysts 2023. [DOI: 10.3390/catal13030591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
Abstract
The enzymatic degradation of the recalcitrant poly(ethylene terephthalate) (PET) has been an important biotechnological goal. The present review focuses on the state of the art in enzymatic degradation of PET, and the challenges ahead. This review covers (i) enzymes acting on PET, (ii) protein improvements through selection or engineering, (iii) strategies to improve biocatalyst–polymer interaction and monomer yields. Finally, this review discusses critical points on PET degradation, and their related experimental aspects, that include the control of physicochemical parameters. The search for, and engineering of, PET hydrolases, have been widely studied to achieve this, and several examples are discussed here. Many enzymes, from various microbial sources, have been studied and engineered, but recently true PET hydrolases (PETases), active at moderate temperatures, were reported. For a circular economy process, terephtalic acid (TPA) production is critical. Some thermophilic cutinases and engineered PETases have been reported to release terephthalic acid in significant amounts. Some bottlenecks in enzyme performance are discussed, including enzyme activity, thermal stability, substrate accessibility, PET microstructures, high crystallinity, molecular mass, mass transfer, and efficient conversion into reusable fragments.
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27
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Tournier V, Duquesne S, Guillamot F, Cramail H, Taton D, Marty A, André I. Enzymes' Power for Plastics Degradation. Chem Rev 2023; 123:5612-5701. [PMID: 36916764 DOI: 10.1021/acs.chemrev.2c00644] [Citation(s) in RCA: 56] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Plastics are everywhere in our modern way of living, and their production keeps increasing every year, causing major environmental concerns. Nowadays, the end-of-life management involves accumulation in landfills, incineration, and recycling to a lower extent. This ecological threat to the environment is inspiring alternative bio-based solutions for plastic waste treatment and recycling toward a circular economy. Over the past decade, considerable efforts have been made to degrade commodity plastics using biocatalytic approaches. Here, we provide a comprehensive review on the recent advances in enzyme-based biocatalysis and in the design of related biocatalytic processes to recycle or upcycle commodity plastics, including polyesters, polyamides, polyurethanes, and polyolefins. We also discuss scope and limitations, challenges, and opportunities of this field of research. An important message from this review is that polymer-assimilating enzymes are very likely part of the solution to reaching a circular plastic economy.
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Affiliation(s)
- Vincent Tournier
- Carbios, Parc Cataroux-Bâtiment B80, 8 rue de la Grolière, 63100 Clermont-Ferrand, France
| | - Sophie Duquesne
- Toulouse Biotechnology Institute, TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France, 135, avenue de Rangueil, F-31077 Toulouse Cedex 04, France
| | - Frédérique Guillamot
- Carbios, Parc Cataroux-Bâtiment B80, 8 rue de la Grolière, 63100 Clermont-Ferrand, France
| | - Henri Cramail
- Université Bordeaux, CNRS, Bordeaux INP, LCPO, 16 Avenue Pey-Berland, 33600 Pessac, France
| | - Daniel Taton
- Université Bordeaux, CNRS, Bordeaux INP, LCPO, 16 Avenue Pey-Berland, 33600 Pessac, France
| | - Alain Marty
- Carbios, Parc Cataroux-Bâtiment B80, 8 rue de la Grolière, 63100 Clermont-Ferrand, France
| | - Isabelle André
- Toulouse Biotechnology Institute, TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France, 135, avenue de Rangueil, F-31077 Toulouse Cedex 04, France
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28
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Kulkarni A, Quintens G, Pitet LM. Trends in Polyester Upcycling for Diversifying a Problematic Waste Stream. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Affiliation(s)
- Amruta Kulkarni
- Advanced Functional Polymers (AFP) Laboratory, Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
| | - Greg Quintens
- Advanced Functional Polymers (AFP) Laboratory, Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
| | - Louis M. Pitet
- Advanced Functional Polymers (AFP) Laboratory, Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
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29
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Microbial Enzyme Biotechnology to Reach Plastic Waste Circularity: Current Status, Problems and Perspectives. Int J Mol Sci 2023; 24:ijms24043877. [PMID: 36835289 PMCID: PMC9967032 DOI: 10.3390/ijms24043877] [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: 01/22/2023] [Revised: 02/08/2023] [Accepted: 02/10/2023] [Indexed: 02/17/2023] Open
Abstract
The accumulation of synthetic plastic waste in the environment has become a global concern. Microbial enzymes (purified or as whole-cell biocatalysts) represent emerging biotechnological tools for waste circularity; they can depolymerize materials into reusable building blocks, but their contribution must be considered within the context of present waste management practices. This review reports on the prospective of biotechnological tools for plastic bio-recycling within the framework of plastic waste management in Europe. Available biotechnology tools can support polyethylene terephthalate (PET) recycling. However, PET represents only ≈7% of unrecycled plastic waste. Polyurethanes, the principal unrecycled waste fraction, together with other thermosets and more recalcitrant thermoplastics (e.g., polyolefins) are the next plausible target for enzyme-based depolymerization, even if this process is currently effective only on ideal polyester-based polymers. To extend the contribution of biotechnology to plastic circularity, optimization of collection and sorting systems should be considered to feed chemoenzymatic technologies for the treatment of more recalcitrant and mixed polymers. In addition, new bio-based technologies with a lower environmental impact in comparison with the present approaches should be developed to depolymerize (available or new) plastic materials, that should be designed for the required durability and for being susceptible to the action of enzymes.
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30
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Schubert S, Schaller K, Bååth JA, Hunt C, Borch K, Jensen K, Brask J, Westh P. Reaction Pathways for the Enzymatic Degradation of Poly(Ethylene Terephthalate): What Characterizes an Efficient PET-Hydrolase? Chembiochem 2023; 24:e202200516. [PMID: 36399069 PMCID: PMC10108200 DOI: 10.1002/cbic.202200516] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/16/2022] [Accepted: 11/16/2022] [Indexed: 11/19/2022]
Abstract
Bioprocessing of polyester waste has emerged as a promising tool in the quest for a cyclic plastic economy. One key step is the enzymatic breakdown of the polymer, and this entails a complicated pathway with substrates, intermediates, and products of variable size and solubility. We have elucidated this pathway for poly(ethylene terephthalate) (PET) and four enzymes. Specifically, we combined different kinetic measurements and a novel stochastic model and found that the ability to hydrolyze internal bonds in the polymer (endo-lytic activity) was a key parameter for overall enzyme performance. Endo-lytic activity promoted the release of soluble PET fragments with two or three aromatic rings, which, in turn, were broken down with remarkable efficiency (kcat /KM values of about 105 M-1 s-1 ) in the aqueous bulk. This meant that approximatly 70 % of the final, monoaromatic products were formed via soluble di- or tri-aromatic intermediates.
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Affiliation(s)
- Sune Schubert
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
| | - Kay Schaller
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
| | | | - Cameron Hunt
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
| | - Kim Borch
- Novozymes A/S, Biologiens Vej 2, 2800 Kgs., Lyngby, Denmark
| | - Kenneth Jensen
- Novozymes A/S, Biologiens Vej 2, 2800 Kgs., Lyngby, Denmark
| | - Jesper Brask
- Novozymes A/S, Biologiens Vej 2, 2800 Kgs., Lyngby, Denmark
| | - Peter Westh
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
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31
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Hayes HC, Luk LYP. Investigating the effects of cyclic topology on the performance of a plastic degrading enzyme for polyethylene terephthalate degradation. Sci Rep 2023; 13:1267. [PMID: 36690710 PMCID: PMC9870871 DOI: 10.1038/s41598-023-27780-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 01/09/2023] [Indexed: 01/24/2023] Open
Abstract
Agitation is a commonly encountered stress for enzymes during all stages of production and application, but investigations that aim to improve their tolerance using topological engineering have yet to be reported. Here, the plastic-degrading enzyme IsPETase was cyclized in a range of topologies including a cyclic monomer, cyclic dimer and catenane using SpyTag/SpyCatcher technologies, and their tolerance towards different stresses including mechanical agitation was investigated. The cyclic dimer and catenane topologies were less susceptible to agitation-induced inactivation resulting in enhancement of polyethylene terephthalate (PET) degradation. While contrary to conventional belief, cyclic topologies did not improve tolerance of IsPETase towards heat or proteolytic treatment, the close proximity of active sites in the dimeric and catenane variants was found to enhance PET conversion into small soluble products. Together, these findings illustrate that it is worthwhile to explore the topology engineering of enzymes used in heterogeneous catalysis as it improves factors that are often overlooked in homogeneous catalysis studies.
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Affiliation(s)
- Heather C Hayes
- School of Chemistry, Cardiff University Main Building, Park Place, Cardiff, CF10 3AT, UK
- Cardiff Catalysis Institute, Cardiff University Main Building, Park Place, Cardiff, CF10 3AT, UK
| | - Louis Y P Luk
- School of Chemistry, Cardiff University Main Building, Park Place, Cardiff, CF10 3AT, UK.
- Cardiff Catalysis Institute, Cardiff University Main Building, Park Place, Cardiff, CF10 3AT, UK.
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32
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Holst LH, Madsen NG, Toftgård FT, Rønne F, Moise IM, Petersen EI, Fojan P. De novo design of a polycarbonate hydrolase. Protein Eng Des Sel 2023; 36:gzad022. [PMID: 38035789 DOI: 10.1093/protein/gzad022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 10/31/2023] [Accepted: 11/14/2023] [Indexed: 12/02/2023] Open
Abstract
Enzymatic degradation of plastics is currently limited to the use of engineered natural enzymes. As of yet, all engineering approaches applied to plastic degrading enzymes retain the natural $\alpha /\beta $-fold. While mutations can be used to increase thermostability, an inherent maximum likely exists for the $\alpha /\beta $-fold. It is thus of interest to introduce catalytic activity toward plastics in a different protein fold to escape the sequence space of plastic degrading enzymes. Here, a method for designing highly thermostable enzymes that can degrade plastics is described. With the help of Rosetta an active site catalysing the hydrolysis of polycarbonate is introduced into a set of thermostable scaffolds. Through computational evaluation, a potential PCase was selected and produced recombinantly in Escherichia coli. Thermal analysis suggests that the design has a melting temperature of >95$^{\circ }$C. Activity toward polycarbonate was confirmed using atomic force spectroscopy (AFM), proving the successful design of a PCase.
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Affiliation(s)
- Laura H Holst
- Material Science and Engineering Group, Department of Materials and Production, Aalborg University, 9000 Aalborg, Denmark
| | - Niklas G Madsen
- Material Science and Engineering Group, Department of Materials and Production, Aalborg University, 9000 Aalborg, Denmark
| | - Freja T Toftgård
- Material Science and Engineering Group, Department of Materials and Production, Aalborg University, 9000 Aalborg, Denmark
| | - Freja Rønne
- Material Science and Engineering Group, Department of Materials and Production, Aalborg University, 9000 Aalborg, Denmark
| | - Ioana-Malina Moise
- Material Science and Engineering Group, Department of Materials and Production, Aalborg University, 9000 Aalborg, Denmark
| | - Evamaria I Petersen
- Material Science and Engineering Group, Department of Materials and Production, Aalborg University, 9000 Aalborg, Denmark
| | - Peter Fojan
- Material Science and Engineering Group, Department of Materials and Production, Aalborg University, 9000 Aalborg, Denmark
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33
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Joho Y, Vongsouthi V, Spence MA, Ton J, Gomez C, Tan LL, Kaczmarski JA, Caputo AT, Royan S, Jackson CJ, Ardevol A. Ancestral Sequence Reconstruction Identifies Structural Changes Underlying the Evolution of Ideonella sakaiensis PETase and Variants with Improved Stability and Activity. Biochemistry 2023; 62:437-450. [PMID: 35951410 DOI: 10.1021/acs.biochem.2c00323] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The improved production, recycling, and removal of plastic waste, such as polyethylene terephthalate (PET), are pressing environmental and economic issues for society. Biocatalytic (enzymatic) PET depolymerization is potentially a sustainable, low-energy solution to PET recycling, especially when compared with current disposal methods such as landfills, incineration, or gasification. IsPETase has been extensively studied for its use in PET depolymerization; however, its evolution from cutinases is not fully understood, and most engineering studies have neglected the majority of the available sequence space remote from the active site. In this study, ancestral protein reconstruction (ASR) has been used to trace the evolutionary trajectory from ancient serine hydrolases to IsPETase, while ASR and the related design approach, protein repair one-stop shop, were used to identify enzyme variants with improved activity and stability. Kinetic and structural characterization of these variants reveals new insights into the evolution of PETase activity and the role of second-shell mutations around the active site. Among the designed and reconstructed variants, we identified several with melting points 20 °C higher than that of IsPETase and two variants with significantly higher catalytic activity.
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Affiliation(s)
- Yvonne Joho
- Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Clayton, Victoria 3168, Australia.,Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Vanessa Vongsouthi
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Matthew A Spence
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Jennifer Ton
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Chloe Gomez
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Li Lynn Tan
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Joe A Kaczmarski
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.,ARC Centre of Excellence for Innovations in Synthetic Biology, Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Alessandro T Caputo
- Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Clayton, Victoria 3168, Australia
| | - Santana Royan
- Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Clayton, Victoria 3168, Australia
| | - Colin J Jackson
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.,ARC Centre of Excellence for Innovations in Peptide & Protein Science, Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.,ARC Centre of Excellence for Innovations in Synthetic Biology, Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Albert Ardevol
- Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Clayton, Victoria 3168, Australia.,CSIRO Synthetic Biology Future Science Platform, GPO Box 1700, Canberra, ACT 2601, Australia
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34
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Maheswaran B, Al-Ansari M, Al-Humaid L, Sebastin Raj J, Kim W, Karmegam N, Mohamed Rafi K. In vivo degradation of polyethylene terephthalate using microbial isolates from plastic polluted environment. CHEMOSPHERE 2023; 310:136757. [PMID: 36228720 DOI: 10.1016/j.chemosphere.2022.136757] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 09/23/2022] [Accepted: 10/02/2022] [Indexed: 06/16/2023]
Abstract
Accumulation of plastics alarms a risk to the environment worldwide. As polyethylene pterephthalate (PET) degrades slowly and produces hazardous substances, therefore, it is now essential to eliminate plastic wastes from the environment. Given that, the current study is concerned with PET degradation potential of naturally occurring microbial strains isolated from plastic waste dumping sites, Sarcina aurantiaca (TB3), Bacillus subtilis (TB8), Aspergillus flavus (STF1), Aspergillus niger (STF2). To test the biodegradability of PET films, the films were incubated for 60 days at 37 °C with the microorganisms designated as TB3, TB8, STF1, STF2 and the microbial consortium (TB3+TB8+STF1+STF2) in Minimal Salt Medium and Bushnell Hass Broth. Hydrophobicity, viability, and total protein content of isolates were investigated. Using Field Emission Scanning Electron Microscopy and Fourier Transform Infrared Spectrophotometry to measure variations in functional groups and carbonyl index on PET surface, biodegradation process was affirmed by fissures and modified surfaces. Results revealed that the microbial consortium (S. aurantiaca + B. subtilis + A. flavus + A. niger) that the weight loss of PET films was 28.78%. The microbial consortium could be used to treat PET waste, posing no health or environmental risks. The developed microbial consortium has the potential to degrade PET, hence can be employed for eliminating PET in plastic contaminated sites.
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Affiliation(s)
- Baskaran Maheswaran
- Post Graduate and Research Department of Biotechnology, Jamal Mohamed College (Autonomous), Affiliated to Bharathidasan University, Tiruchirappalli, 620 020, Tamil Nadu, India
| | - Mysoon Al-Ansari
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Latifah Al-Humaid
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Joseph Sebastin Raj
- Post Graduate and Research Department of Biotechnology, Jamal Mohamed College (Autonomous), Affiliated to Bharathidasan University, Tiruchirappalli, 620 020, Tamil Nadu, India.
| | - Woong Kim
- Department of Environmental Engineering, Kyungpook National University, Daegu, 41566, Republic of Korea.
| | - Natchimuthu Karmegam
- PG and Research Department of Botany, Government Arts College (Autonomous), Salem, 636 007, Tamil Nadu, India.
| | - Kasim Mohamed Rafi
- Post Graduate and Research Department of Botany, Jamal Mohamed College (Autonomous), Affiliated to Bharathidasan University, Tiruchirappalli, 620 020, Tamil Nadu, India
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35
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von Haugwitz G, Han X, Pfaff L, Li Q, Wei H, Gao J, Methling K, Ao Y, Brack Y, Mican J, Feiler CG, Weiss MS, Bednar D, Palm GJ, Lalk M, Lammers M, Damborsky J, Weber G, Liu W, Bornscheuer UT, Wei R. Structural Insights into (Tere)phthalate-Ester Hydrolysis by a Carboxylesterase and Its Role in Promoting PET Depolymerization. ACS Catal 2022; 12:15259-15270. [PMID: 36570084 PMCID: PMC9764356 DOI: 10.1021/acscatal.2c03772] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/09/2022] [Indexed: 12/03/2022]
Abstract
TfCa, a promiscuous carboxylesterase from Thermobifida fusca, was found to hydrolyze polyethylene terephthalate (PET) degradation intermediates such as bis(2-hydroxyethyl) terephthalate (BHET) and mono-(2-hydroxyethyl)-terephthalate (MHET). In this study, we elucidated the structures of TfCa in its apo form, as well as in complex with a PET monomer analogue and with BHET. The structure-function relationship of TfCa was investigated by comparing its hydrolytic activity on various ortho- and para-phthalate esters of different lengths. Structure-guided rational engineering of amino acid residues in the substrate-binding pocket resulted in the TfCa variant I69W/V376A (WA), which showed 2.6-fold and 3.3-fold higher hydrolytic activity on MHET and BHET, respectively, than the wild-type enzyme. TfCa or its WA variant was mixed with a mesophilic PET depolymerizing enzyme variant [Ideonella sakaiensis PETase (IsPETase) PM] to degrade PET substrates of various crystallinity. The dual enzyme system with the wild-type TfCa or its WA variant produced up to 11-fold and 14-fold more terephthalate (TPA) than the single IsPETase PM, respectively. In comparison to the recently published chimeric fusion protein of IsPETase and MHETase, our system requires 10% IsPETase and one-fourth of the reaction time to yield the same amount of TPA under similar PET degradation conditions. Our simple dual enzyme system reveals further advantages in terms of cost-effectiveness and catalytic efficiency since it does not require time-consuming and expensive cross-linking and immobilization approaches.
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Affiliation(s)
- Gerlis von Haugwitz
- Department
of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Xu Han
- Tianjin
Institute of Industrial Biotechnology, Chinese
Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China,National
Technology Innovation Center of Synthetic Biology, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Lara Pfaff
- Department
of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Qian Li
- Tianjin
Institute of Industrial Biotechnology, Chinese
Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China,National
Technology Innovation Center of Synthetic Biology, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Hongli Wei
- Tianjin
Institute of Industrial Biotechnology, Chinese
Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China,National
Technology Innovation Center of Synthetic Biology, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Jian Gao
- Tianjin
Institute of Industrial Biotechnology, Chinese
Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China,National
Technology Innovation Center of Synthetic Biology, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Karen Methling
- Department
of Cellular Biochemistry and Metabolomics, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Yufei Ao
- Department
of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany,University
of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China
| | - Yannik Brack
- Department
of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Jan Mican
- Loschmidt
Laboratories, Department of Experimental Biology and RECETOX, Faculty
of Science, Masaryk University, Kamenice 5/C13, 625 00 Brno, Czech Republic,International
Clinical Research Center, St. Anne’s
University Hospital, Pekarska 53, 656 91 Brno, Czech Republic
| | - Christian G. Feiler
- Macromolecular
Crystallography, Helmholtz-Zentrum Berlin, Alber-Einstein-Straße 15, 12489 Berlin, Germany
| | - Manfred S. Weiss
- Macromolecular
Crystallography, Helmholtz-Zentrum Berlin, Alber-Einstein-Straße 15, 12489 Berlin, Germany
| | - David Bednar
- Loschmidt
Laboratories, Department of Experimental Biology and RECETOX, Faculty
of Science, Masaryk University, Kamenice 5/C13, 625 00 Brno, Czech Republic,International
Clinical Research Center, St. Anne’s
University Hospital, Pekarska 53, 656 91 Brno, Czech Republic
| | - Gottfried J. Palm
- Department
of Synthetic and Structural Biochemistry, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Michael Lalk
- Department
of Cellular Biochemistry and Metabolomics, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Michael Lammers
- Department
of Synthetic and Structural Biochemistry, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Jiri Damborsky
- Loschmidt
Laboratories, Department of Experimental Biology and RECETOX, Faculty
of Science, Masaryk University, Kamenice 5/C13, 625 00 Brno, Czech Republic,International
Clinical Research Center, St. Anne’s
University Hospital, Pekarska 53, 656 91 Brno, Czech Republic
| | - Gert Weber
- Macromolecular
Crystallography, Helmholtz-Zentrum Berlin, Alber-Einstein-Straße 15, 12489 Berlin, Germany
| | - Weidong Liu
- Tianjin
Institute of Industrial Biotechnology, Chinese
Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China,National
Technology Innovation Center of Synthetic Biology, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China,University
of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China,
| | - Uwe T. Bornscheuer
- Department
of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany,
| | - Ren Wei
- Department
of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany,
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36
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Tarazona NA, Wei R, Brott S, Pfaff L, Bornscheuer UT, Lendlein A, Machatschek R. Rapid depolymerization of poly(ethylene terephthalate) thin films by a dual-enzyme system and its impact on material properties. CHEM CATALYSIS 2022; 2:3573-3589. [PMID: 37350932 PMCID: PMC10284027 DOI: 10.1016/j.checat.2022.11.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/17/2022] [Accepted: 11/04/2022] [Indexed: 06/24/2023]
Abstract
Enzymatic hydrolysis holds great promise for plastic waste recycling and upcycling. The interfacial catalysis mode, and the variability of polymer specimen properties under different degradation conditions, add to the complexity and difficulty of understanding polymer cleavage and engineering better biocatalysts. We present a systemic approach to studying the enzyme-catalyzed surface erosion of poly(ethylene terephthalate) (PET) while monitoring/controlling operating conditions in real time with simultaneous detection of mass loss and changes in viscoelastic behavior. PET nanofilms placed on water showed a porous morphology and a thickness-dependent glass transition temperature (Tg) between 40°C and 44°C, which is >20°C lower than the Tg of bulk amorphous PET. Hydrolysis by a dual-enzyme system containing thermostabilized variants of Ideonella sakaiensis PETase and MHETase resulted in a maximum depolymerization of 70% in 1 h at 50°C. We demonstrate that increased accessible surface area, amorphization, and Tg reduction speed up PET degradation while simultaneously lowering the threshold for degradation-induced crystallization.
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Affiliation(s)
- Natalia A. Tarazona
- Institute of Active Polymers, Helmholtz-Zentrum Hereon, Kantstraße 55, 14513 Teltow, Germany
| | - Ren Wei
- Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Straße 8, 17489 Greifswald, Germany
| | - Stefan Brott
- Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Straße 8, 17489 Greifswald, Germany
| | - Lara Pfaff
- Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Straße 8, 17489 Greifswald, Germany
| | - Uwe T. Bornscheuer
- Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Straße 8, 17489 Greifswald, Germany
| | - Andreas Lendlein
- Institute of Active Polymers, Helmholtz-Zentrum Hereon, Kantstraße 55, 14513 Teltow, Germany
- Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Straße 24-25, 14469 Potsdam, Germany
| | - Rainhard Machatschek
- Institute of Active Polymers, Helmholtz-Zentrum Hereon, Kantstraße 55, 14513 Teltow, Germany
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37
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Lomwongsopon P, Varrone C. Critical Review on the Progress of Plastic Bioupcycling Technology as a Potential Solution for Sustainable Plastic Waste Management. Polymers (Basel) 2022; 14:polym14224996. [PMID: 36433123 PMCID: PMC9692586 DOI: 10.3390/polym14224996] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/11/2022] [Accepted: 11/14/2022] [Indexed: 11/19/2022] Open
Abstract
Plastic production worldwide has doubled in the last two decades and is expected to reach a four-fold increase by 2050. The durability of plastic makes them a perfect material for many applications, but it is also a key limitation to their end-of-life management. The current plastic lifecycle is far from circular, with only 13% being collected for recycling and 9% being successfully recycled, indicating the failure of current recycling technology. The remaining plastic waste streams are thus incinerated, landfilled, or worse, mismanaged, leading to them leaking into the environment. To promote plastic circularity, keeping material in the loop is a priority and represents a more sustainable solution. This can be achieved through the reuse of plastic items, or by using plastic waste as a resource for new materials, instead of discarding them as waste. As the discovery of plastic-degrading/utilizing microorganisms and enzymes has been extensively reported recently, the possibility of developing biological plastic upcycling processes is opening up. An increasing amount of studies have investigated the use of plastic as a carbon source for biotechnological processes to produce high-value compounds such as bioplastics, biochemicals, and biosurfactants. In the current review, the advancements in fossil-based plastic bio- and thermochemical upcycling technologies are presented and critically discussed. In particular, we highlight the developed (bio)depolymerization coupled with bioconversion/fermentation processes to obtain industrially valuable products. This review is expected to contribute to the future development and scale-up of effective plastic bioupcycling processes that can act as a drive to increase waste removal from the environment and valorize post-consumer plastic streams, thus accelerating the implementation of a circular (plastic) economy.
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38
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Chow J, Perez‐Garcia P, Dierkes R, Streit WR. Microbial enzymes will offer limited solutions to the global plastic pollution crisis. Microb Biotechnol 2022; 16:195-217. [PMID: 36099200 PMCID: PMC9871534 DOI: 10.1111/1751-7915.14135] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/09/2022] [Accepted: 08/14/2022] [Indexed: 01/27/2023] Open
Abstract
Global economies depend on the use of fossil-fuel-based polymers with 360-400 million metric tons of synthetic polymers being produced per year. Unfortunately, an estimated 60% of the global production is disposed into the environment. Within this framework, microbiologists have tried to identify plastic-active enzymes over the past decade. Until now, this research has largely failed to deliver functional biocatalysts acting on the commodity polymers such as polyethylene (PE), polypropylene (PP), polyvinylchloride (PVC), ether-based polyurethane (PUR), polyamide (PA), polystyrene (PS) and synthetic rubber (SR). However, few enzymes are known to act on low-density and low-crystalline (amorphous) polyethylene terephthalate (PET) and ester-based PUR. These above-mentioned polymers represent >95% of all synthetic plastics produced. Therefore, the main challenge microbiologists are currently facing is in finding polymer-active enzymes targeting the majority of fossil-fuel-based plastics. However, identifying plastic-active enzymes either to implement them in biotechnological processes or to understand their potential role in nature is an emerging research field. The application of these enzymes is still in its infancy. Here, we summarize the current knowledge on microbial plastic-active enzymes, their global distribution and potential impact on plastic degradation in industrial processes and nature. We further outline major challenges in finding novel plastic-active enzymes, optimizing known ones by synthetic approaches and problems arising through falsely annotated and unfiltered use of database entries. Finally, we highlight potential biotechnological applications and possible re- and upcycling concepts using microorganisms.
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Affiliation(s)
- Jennifer Chow
- Department of Microbiology and BiotechnologyUniversity of HamburgHamburgGermany
| | - Pablo Perez‐Garcia
- Department of Microbiology and BiotechnologyUniversity of HamburgHamburgGermany
| | - Robert Dierkes
- Department of Microbiology and BiotechnologyUniversity of HamburgHamburgGermany
| | - Wolfgang R. Streit
- Department of Microbiology and BiotechnologyUniversity of HamburgHamburgGermany
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39
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Eiamthong B, Meesawat P, Wongsatit T, Jitdee J, Sangsri R, Patchsung M, Aphicho K, Suraritdechachai S, Huguenin-Dezot N, Tang S, Suginta W, Paosawatyanyong B, Babu MM, Chin JW, Pakotiprapha D, Bhanthumnavin W, Uttamapinant C. Discovery and Genetic Code Expansion of a Polyethylene Terephthalate (PET) Hydrolase from the Human Saliva Metagenome for the Degradation and Bio-Functionalization of PET. Angew Chem Int Ed Engl 2022; 61:e202203061. [PMID: 35656865 PMCID: PMC7613822 DOI: 10.1002/anie.202203061] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Indexed: 11/24/2022]
Abstract
We report a bioinformatic workflow and subsequent discovery of a new polyethylene terephthalate (PET) hydrolase, which we named MG8, from the human saliva metagenome. MG8 has robust PET plastic degradation activities under different temperature and salinity conditions, outperforming several naturally occurring and engineered hydrolases in degrading PET. Moreover, we genetically encoded 2,3-diaminopropionic acid (DAP) in place of the catalytic serine residue of MG8, thereby converting a PET hydrolase into a covalent binder for bio-functionalization of PET. We show that MG8(DAP), in conjunction with a split green fluorescent protein system, can be used to attach protein cargos to PET as well as other polyester plastics. The discovery of a highly active PET hydrolase from the human metagenome-currently an underexplored resource for industrial enzyme discovery-as well as the repurposing of such an enzyme into a plastic functionalization tool, should facilitate ongoing efforts to degrade and maximize reusability of PET.
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Affiliation(s)
- Bhumrapee Eiamthong
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | - Piyachat Meesawat
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | - Thanakrit Wongsatit
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | - Jariya Jitdee
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Raweewan Sangsri
- Department of Biochemistry and Center for Excellence in Protein and Enzyme Technology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Maturada Patchsung
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | - Kanokpol Aphicho
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | - Surased Suraritdechachai
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | | | - Shan Tang
- Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Wipa Suginta
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | | | - M Madan Babu
- Department of Structural Biology and Center of Excellence for Data Driven Discovery, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Danaya Pakotiprapha
- Department of Biochemistry and Center for Excellence in Protein and Enzyme Technology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Worawan Bhanthumnavin
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Chayasith Uttamapinant
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
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40
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Pfaff L, Gao J, Li Z, Jäckering A, Weber G, Mican J, Chen Y, Dong W, Han X, Feiler CG, Ao YF, Badenhorst CPS, Bednar D, Palm GJ, Lammers M, Damborsky J, Strodel B, Liu W, Bornscheuer UT, Wei R. Multiple Substrate Binding Mode-Guided Engineering of a Thermophilic PET Hydrolase. ACS Catal 2022; 12:9790-9800. [PMID: 35966606 PMCID: PMC9361285 DOI: 10.1021/acscatal.2c02275] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 07/06/2022] [Indexed: 12/13/2022]
Abstract
![]()
Thermophilic polyester hydrolases (PES-H) have recently
enabled
biocatalytic recycling of the mass-produced synthetic polyester polyethylene
terephthalate (PET), which has found widespread use in the packaging
and textile industries. The growing demand for efficient PET hydrolases
prompted us to solve high-resolution crystal structures of two metagenome-derived
enzymes (PES-H1 and PES-H2) and notably also in complex with various
PET substrate analogues. Structural analyses and computational modeling
using molecular dynamics simulations provided an understanding of
how product inhibition and multiple substrate binding modes influence
key mechanistic steps of enzymatic PET hydrolysis. Key residues involved
in substrate-binding and those identified previously as mutational
hotspots in homologous enzymes were subjected to mutagenesis. At 72
°C, the L92F/Q94Y variant of PES-H1 exhibited 2.3-fold and 3.4-fold
improved hydrolytic activity against amorphous PET films and pretreated
real-world PET waste, respectively. The R204C/S250C variant of PES-H1
had a 6.4 °C higher melting temperature than the wild-type enzyme
but retained similar hydrolytic activity. Under optimal reaction conditions,
the L92F/Q94Y variant of PES-H1 hydrolyzed low-crystallinity PET materials
2.2-fold more efficiently than LCC ICCG, which was previously the
most active PET hydrolase reported in the literature. This property
makes the L92F/Q94Y variant of PES-H1 a good candidate for future
applications in industrial plastic recycling processes.
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Affiliation(s)
- Lara Pfaff
- Department of Biotechnology & Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Jian Gao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, 32 West Seventh Avenue, Tianjin
Airport Economic Area, Tianjin 300308, China
| | - Zhishuai Li
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049 China
| | - Anna Jäckering
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Wilhelm-Johnen-Straße, 52428 Jülich, Germany
- Institute of Theoretical and Computational Chemistry, Heinrich Heine University, Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Gert Weber
- Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
| | - Jan Mican
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/C13, 625 00 Brno, Czech Republic
| | - Yinping Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Xu Han
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, 32 West Seventh Avenue, Tianjin
Airport Economic Area, Tianjin 300308, China
| | - Christian G. Feiler
- Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
| | - Yu-Fei Ao
- Department of Biotechnology & Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
- CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun North First Street 2, Beijing 100190, China
| | - Christoffel P. S. Badenhorst
- Department of Biotechnology & Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - David Bednar
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/C13, 625 00 Brno, Czech Republic
- International Clinical Research Center, St. Anne’s University Hospital, Pekarska 53, 656 91 Brno, Czech Republic
| | - Gottfried J. Palm
- Department Synthetic and Structural Biochemistry, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Michael Lammers
- Department Synthetic and Structural Biochemistry, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Jiri Damborsky
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/C13, 625 00 Brno, Czech Republic
- International Clinical Research Center, St. Anne’s University Hospital, Pekarska 53, 656 91 Brno, Czech Republic
| | - Birgit Strodel
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Wilhelm-Johnen-Straße, 52428 Jülich, Germany
- Institute of Theoretical and Computational Chemistry, Heinrich Heine University, Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Weidong Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, 32 West Seventh Avenue, Tianjin
Airport Economic Area, Tianjin 300308, China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049 China
| | - Uwe T. Bornscheuer
- Department of Biotechnology & Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
| | - Ren Wei
- Department of Biotechnology & Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487 Greifswald, Germany
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41
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Meyer Cifuentes IE, Wu P, Zhao Y, Liu W, Neumann-Schaal M, Pfaff L, Barys J, Li Z, Gao J, Han X, Bornscheuer UT, Wei R, Öztürk B. Molecular and Biochemical Differences of the Tandem and Cold-Adapted PET Hydrolases Ple628 and Ple629, Isolated From a Marine Microbial Consortium. Front Bioeng Biotechnol 2022; 10:930140. [PMID: 35935485 PMCID: PMC9350882 DOI: 10.3389/fbioe.2022.930140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 05/23/2022] [Indexed: 01/27/2023] Open
Abstract
Polybutylene adipate terephthalate (PBAT) is a biodegradable alternative to polyethylene and can be broadly used in various applications. These polymers can be degraded by hydrolases of terrestrial and aquatic origin. In a previous study, we identified tandem PETase-like hydrolases (Ples) from the marine microbial consortium I1 that were highly expressed when a PBAT blend was supplied as the only carbon source. In this study, the tandem Ples, Ple628 and Ple629, were recombinantly expressed and characterized. Both enzymes are mesophilic and active on a wide range of oligomers. The activities of the Ples differed greatly when model substrates, PBAT-modified polymers or PET nanoparticles were supplied. Ple629 was always more active than Ple628. Crystal structures of Ple628 and Ple629 revealed a structural similarity to other PETases and can be classified as member of the PETases IIa subclass, α/β hydrolase superfamily. Our results show that the predicted functions of Ple628 and Ple629 agree with the bioinformatic predictions, and these enzymes play a significant role in the plastic degradation by the consortium.
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Affiliation(s)
- Ingrid E. Meyer Cifuentes
- Junior Research Group Microbial Biotechnology, Leibniz Institute DSMZ—German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Pan Wu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Yipei Zhao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Weidong Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Meina Neumann-Schaal
- Research Group Metabolomics, Leibniz Institute DSMZ—German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Lara Pfaff
- Junior Research Group Plastic Biodegradation, Institute of Biochemistry, Department of Biotechnology and Enzyme Catalysis, University of Greifswald, Greifswald, Germany
| | - Justyna Barys
- Junior Research Group Microbial Biotechnology, Leibniz Institute DSMZ—German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Zhishuai Li
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jian Gao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Xu Han
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Uwe T. Bornscheuer
- Department of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Greifswald, Germany
| | - Ren Wei
- Junior Research Group Plastic Biodegradation, Institute of Biochemistry, Department of Biotechnology and Enzyme Catalysis, University of Greifswald, Greifswald, Germany
| | - Başak Öztürk
- Junior Research Group Microbial Biotechnology, Leibniz Institute DSMZ—German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
- *Correspondence: Başak Öztürk,
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42
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An NMR look at an engineered PET depolymerase. Biophys J 2022; 121:2882-2894. [PMID: 35794828 PMCID: PMC9388554 DOI: 10.1016/j.bpj.2022.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 06/15/2022] [Accepted: 06/30/2022] [Indexed: 12/30/2022] Open
Abstract
Plastic environmental pollution is a major issue that our generation must face to protect our planet. Plastic recycling has the potential not only to reduce the pollution but also to limit the need for fossil-fuel-based production of new plastics. Enzymes capable of breaking down plastic could thereby support such a circular economy. Polyethylene terephthalate (PET) degrading enzymes have recently attracted considerable interest and have been subjected to intensive enzyme engineering to improve their characteristics. A quadruple mutant of Leaf-branch Compost Cutinase (LCC) was identified as a most efficient and promising enzyme. Here, we use NMR to follow the initial LCC enzyme through its different mutations that lead to its improved performance. We experimentally define the two calcium-binding sites and show their importance on the all-or-nothing thermal unfolding process, which occurs at a temperature of 72°C close to the PET glass transition temperature. Using various NMR probes such as backbone amide, methyl group, and histidine side-chain resonances, we probe the interaction of the enzymes with mono-(2-hydroxyethyl)terephthalic acid. The latter experiments are interpreted in terms of accessibility of the active site to the polymer chain.
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43
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Eiamthong B, Meesawat P, Wongsatit T, Jitdee J, Sangsri R, Patchsung M, Aphicho K, Suraritdechachai S, Huguenin-Dezot N, Tang S, Suginta W, Paosawatyanyong B, Babu MM, Chin JW, Pakotiprapha D, Bhanthumnavin W, Uttamapinant C. Discovery and Genetic Code Expansion of a Polyethylene Terephthalate (PET) Hydrolase from the Human Saliva Metagenome for the Degradation and Bio‐Functionalization of PET. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Bhumrapee Eiamthong
- Vidyasirimedhi Institute of Science and Technology School of Biomolecular Science and Engineering THAILAND
| | - Piyachat Meesawat
- Vidyasirimedhi Institute of Science and Technology School of Biomolecular Science and Engineering THAILAND
| | - Thanakrit Wongsatit
- Vidyasirimedhi Institute of Science and Technology School of Biomolecular Science and Engineering THAILAND
| | - Jariya Jitdee
- Chulalongkorn University Faculty of Science Chemistry THAILAND
| | | | - Maturada Patchsung
- Vidyasirimedhi Institute of Science and Technology Biomolecular Science and Engineering THAILAND
| | - Kanokpol Aphicho
- Vidyasirimedhi Institute of Science and Technology Biomolecular Science and Engineering THAILAND
| | - Surased Suraritdechachai
- Vidyasirimedhi Institute of Science and Technology Biomolecular Science and Engineering THAILAND
| | | | - Shan Tang
- MRC Laboratory of Molecular Biology Protein and nucleic acid chemistry UNITED KINGDOM
| | - Wipa Suginta
- Vidyasirimedhi Institute of Science and Technology Biomolecular Science and Engineering THAILAND
| | | | - M. Madan Babu
- St Jude Children's Research Hospital Department of Structural Biology Structural Biology UNITED STATES
| | - Jason W Chin
- MRC Laboratory of Molecular Biology Protein and nucleic acid chemistry UNITED KINGDOM
| | | | | | - Chayasith Uttamapinant
- Vidyasirimedhi Institute of Science and Technology School of Biomolecular Science and Engineering 555 Moo 1 PayupnaiWangchan Valley 21210 Rayong THAILAND
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44
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Alcántara AR, Domínguez de María P, Littlechild JA, Schürmann M, Sheldon RA, Wohlgemuth R. Biocatalysis as Key to Sustainable Industrial Chemistry. CHEMSUSCHEM 2022; 15:e202102709. [PMID: 35238475 DOI: 10.1002/cssc.202102709] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/10/2022] [Indexed: 06/14/2023]
Abstract
The role and power of biocatalysis in sustainable chemistry has been continuously brought forward step by step to its present outstanding position. The problem-solving capabilities of biocatalysis have been realized by numerous substantial achievements in biology, chemistry and engineering. Advances and breakthroughs in the life sciences and interdisciplinary cooperation with chemistry have clearly accelerated the implementation of biocatalytic synthesis in modern chemistry. Resource-efficient biocatalytic manufacturing processes have already provided numerous benefits to sustainable chemistry as well as customer-centric value creation in the pharmaceutical, food, flavor, fragrance, vitamin, agrochemical, polymer, specialty, and fine chemical industries. Biocatalysis can make significant contributions not only to manufacturing processes, but also to the design of completely new value-creation chains. Biocatalysis can now be considered as a key enabling technology to implement sustainable chemistry.
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Affiliation(s)
- Andrés R Alcántara
- Department of Chemistry in Pharmaceutical Sciences (QUICIFARM), Complutense University of Madrid (UCM), 28040-, Madrid, Spain
| | - Pablo Domínguez de María
- Sustainable Momentum, SL, Av. Ansite 3, 4-6, 35011, Las Palmas de Gran Canaria, Canary Is., Spain
| | - Jennifer A Littlechild
- Henry Wellcome Building for Biocatalysis, Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4QD, United Kingdom
| | | | - Roger A Sheldon
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Braamfontein, Johannesburg, South Africa
| | - Roland Wohlgemuth
- Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, 90-537, Lodz, Poland
- Swiss Coordination Committee for Biotechnology, 8021, Zurich, Switzerland
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45
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Wei R, von Haugwitz G, Pfaff L, Mican J, Badenhorst CP, Liu W, Weber G, Austin HP, Bednar D, Damborsky J, Bornscheuer UT. Mechanism-Based Design of Efficient PET Hydrolases. ACS Catal 2022; 12:3382-3396. [PMID: 35368328 PMCID: PMC8939324 DOI: 10.1021/acscatal.1c05856] [Citation(s) in RCA: 81] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/04/2022] [Indexed: 01/06/2023]
Abstract
Polyethylene terephthalate (PET) is the most widespread synthetic polyester, having been utilized in textile fibers and packaging materials for beverages and food, contributing considerably to the global solid waste stream and environmental plastic pollution. While enzymatic PET recycling and upcycling have recently emerged as viable disposal methods for a circular plastic economy, only a handful of benchmark enzymes have been thoroughly described and subjected to protein engineering for improved properties over the last 16 years. By analyzing the specific material properties of PET and the reaction mechanisms in the context of interfacial biocatalysis, this Perspective identifies several limitations in current enzymatic PET degradation approaches. Unbalanced enzyme-substrate interactions, limited thermostability, and low catalytic efficiency at elevated reaction temperatures, and inhibition caused by oligomeric degradation intermediates still hamper industrial applications that require high catalytic efficiency. To overcome these limitations, successful protein engineering studies using innovative experimental and computational approaches have been published extensively in recent years in this thriving research field and are summarized and discussed in detail here. The acquired knowledge and experience will be applied in the near future to address plastic waste contributed by other mass-produced polymer types (e.g., polyamides and polyurethanes) that should also be properly disposed by biotechnological approaches.
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Affiliation(s)
- Ren Wei
- Institute
of Biochemistry, Department of Biotechnology & Enzyme Catalysis, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany,
| | - Gerlis von Haugwitz
- Institute
of Biochemistry, Department of Biotechnology & Enzyme Catalysis, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
| | - Lara Pfaff
- Institute
of Biochemistry, Department of Biotechnology & Enzyme Catalysis, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
| | - Jan Mican
- Loschmidt
Laboratories, Department of Experimental Biology and RECETOX, Faculty
of Science, Masaryk University, 625 00 Brno, Czech Republic,International
Clinical Research Center, St. Anne’s University Hospital and
Faculty of Medicine, Masaryk University, 656 91 Brno, Czech Republic
| | - Christoffel P.
S. Badenhorst
- Institute
of Biochemistry, Department of Biotechnology & Enzyme Catalysis, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
| | - Weidong Liu
- Tianjin
Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport
Economic Area, Tianjin, 300308, China
| | - Gert Weber
- Macromolecular
Crystallography, Helmholtz-Zentrum Berlin
für Materialien und Energie, Albert-Einstein-Straße 15, D-12489 Berlin, Germany
| | - Harry P. Austin
- Institute
of Biochemistry, Department of Biotechnology & Enzyme Catalysis, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
| | - David Bednar
- Loschmidt
Laboratories, Department of Experimental Biology and RECETOX, Faculty
of Science, Masaryk University, 625 00 Brno, Czech Republic,International
Clinical Research Center, St. Anne’s University Hospital and
Faculty of Medicine, Masaryk University, 656 91 Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt
Laboratories, Department of Experimental Biology and RECETOX, Faculty
of Science, Masaryk University, 625 00 Brno, Czech Republic,International
Clinical Research Center, St. Anne’s University Hospital and
Faculty of Medicine, Masaryk University, 656 91 Brno, Czech Republic
| | - Uwe T. Bornscheuer
- Institute
of Biochemistry, Department of Biotechnology & Enzyme Catalysis, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany,
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