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Liu Y, Peng W, Wei T, Yuan Y, Cao X, Ma M, Sun Q, Li M, Xie F. Strong, anti-swelling, and biodegradable seaweed-based straws with surface mineralized CaCO 3 armor. Carbohydr Polym 2024; 341:122347. [PMID: 38876717 DOI: 10.1016/j.carbpol.2024.122347] [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: 02/15/2024] [Revised: 05/21/2024] [Accepted: 05/28/2024] [Indexed: 06/16/2024]
Abstract
While the extensive utilization of disposable plastic straws has resulted in significant environmental issues such as microplastics and soil and ocean pollution, the quest for alternative straws for versatile use remains a formidable challenge. Here, drawing inspiration from naturally water-resistant materials such as bones and sea urchins, we have developed seaweed-based straws with significantly improved water resistance and mechanical strength via in-situ mineralization of CaCO3 on their surfaces. Specifically, the COO- groups on the G (α-L-guluronate) blocks of alginate were employed to establish a robust cross-linked network, while the COO- groups on the M (β-D-mannuronate) blocks attracted free Ca2+ through electrostatic forces, thereby promoting CaCO3 nucleation. This effectively prevents COOH groups from hydrating, reducing swelling, and results in the fabrication of nano- to micron-sized CaCO3 particles that reinforce the structure without compromising the cross-linked network. Compared with the control group, the S5% sample (prepared with 5 % Na2CO3 solution) exhibited a 102 % increase in water contact angle, a 35 % decrease in swelling degree, and a 35.5 % and 37.5 % increase in ultimate flexural and tensile stress, respectively. Furthermore, the potential use of these straws as a waste for heavy metal adsorption was investigated, addressing environmental concerns while demonstrating economic feasibility.
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Affiliation(s)
- Yuanpu Liu
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, PR China; Qingdao Special Food Research Institute, Qingdao 266109, PR China
| | - Wen Peng
- College of Horticulture, Qingdao Agricultural University, Qingdao 266109, PR China
| | - Ting Wei
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, PR China; Qingdao Special Food Research Institute, Qingdao 266109, PR China
| | - Yajie Yuan
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, PR China; Qingdao Special Food Research Institute, Qingdao 266109, PR China
| | - Xianyu Cao
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, PR China; Qingdao Special Food Research Institute, Qingdao 266109, PR China
| | - Meng Ma
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, PR China; Qingdao Special Food Research Institute, Qingdao 266109, PR China
| | - Qingjie Sun
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, PR China; Qingdao Special Food Research Institute, Qingdao 266109, PR China
| | - Man Li
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, PR China; Qingdao Special Food Research Institute, Qingdao 266109, PR China.
| | - Fengwei Xie
- Department of Chemical Engineering, University of Bath, Bath BA2 7AY, United Kingdom
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Tang S, Ma S, Lin L, Ding Y, Zhang X, Wu X, Zhang Q, Pervez MN, Cao C, Zhao Y. Carrier effects of face mask-derived microplastics on metal ions: Enhanced adsorption by photoaging combined with biofilms, exemplified with Pb(Ⅱ). JOURNAL OF HAZARDOUS MATERIALS 2024; 477:135311. [PMID: 39068889 DOI: 10.1016/j.jhazmat.2024.135311] [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: 06/14/2024] [Revised: 07/16/2024] [Accepted: 07/23/2024] [Indexed: 07/30/2024]
Abstract
Face masks have emerged as a significant source of microplastics (MPs) under the influence of biotic and abiotic interactions. However, the combined effects of abiotic photoaging and biofilm-loading on mask-derived MPs as carriers of metal ions are not clear. We investigated the Pb(Ⅱ) adsorption onto polypropylene (PP) and polyurethane (PU) mask-derived MPs treated by photoaging, biofilm-loading, and both combinations, evaluating the composite risks. PU mask-derived MPs (1.157.47 mg/g) exhibited greater Pb(Ⅱ) adsorption capacity than PP mask-derived MPs (0.842.08 mg/g) because of the presence of intrinsic carbonyl functional groups. Photoaging (30.5%, 88.4%), biofilm-loading (110.7%, 87.1%), and both combinations (146.7%, 547.0%) of PP and PU masks enhanced Pb(Ⅱ) adsorption compared to virgin mask-derived MPs due to the increase of oxygen-containing functional groups. High-throughput sequencing indicated that the structural morphology and chemical composition of masks significantly affected the microbial community. Adsorption mechanisms involved electrostatic force and surface complexation. A combination of photoaging and biofilms increased the ecological risk index of mask-derived MPs in freshwater, showing the risk level to be high (PP mask) and very high (PU mask). This research highlights the crucial role of photoaging combined with biofilms in controlling metal ion adsorption onto mask-derived MPs, thereby increasing the composite risks.
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Affiliation(s)
- Shuai Tang
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming, and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Shengjia Ma
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming, and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Lujian Lin
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen 361102, China
| | - Yimei Ding
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming, and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Xiaoting Zhang
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen 361102, China
| | - Xiaowei Wu
- School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China.
| | - Qun Zhang
- School of Public Health, Shandong Second Medical University, Weifang 261053, China
| | - Md Nahid Pervez
- Department of Environmental and Sustainable Engineering, University at Albany, State University of New York, Albany, NY 12222, USA
| | - Chengjin Cao
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming, and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Yaping Zhao
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming, and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China.
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3
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Tang S, Zhang Q, Xu H, Zhu M, Nahid Pervez M, Wu B, Zhao Y. Fabric structure and polymer composition as key contributors to micro(nano)plastic contamination in face masks. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:135089. [PMID: 38959827 DOI: 10.1016/j.jhazmat.2024.135089] [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: 04/17/2024] [Revised: 06/25/2024] [Accepted: 07/01/2024] [Indexed: 07/05/2024]
Abstract
The surge in face mask use due to COVID-19 has raised concerns about micro(nano)plastics (MNPs) from masks. Herein, focusing on fabric structure and polymer composition, we investigated MNP generation characteristics, mechanisms, and potential risks of surgical polypropylene (PP) and fashionable polyurethane (PU) masks during their wearing and photoaging based on stereomicroscope, μ-Fourier transform infrared spectroscopy (μ-FTIR), and scanning electron microscope (SEM) techniques. Compared with new PP and PU masks (66 ± 16 MPs/PP-mask, 163 ± 83 MPs/PU-mask), single- and multiple-used masks exhibited remarkably increased MP type and abundance (600-1867 MPs/PP-mask, 607-2167 MPs/PU-mask). Disinfection exacerbated endogenous MP generation in masks, with washing (416 MPs/PP-mask, 30,708 MPs/PU-mask) being the most prominent compared to autoclaving (219 MPs/PP-mask, 553 MPs/PU-mask) and alcohol spray (162 MPs/PP-mask, 18,333 MPs/PU-mask). Photoaging led to massive generation of MPs (8.8 × 104-3.7 × 105 MPs/PP-layer, 1.0 × 105 MPs/PU-layer) and NPs (5.2 × 109-3.6 × 1013 NPs/PP-layer, 3.5 × 1012 NPs/PU-layer) from masks, presenting highly fabric structure-dependent aging modes as "fragmentation" for fine fiber-structure PP mask and "erosion" for 3D mesh-structure PU mask. The MNPs derived from PP/PU mask caused significant deformities of Zebrafish (Danio rerio) larvae. These findings underscore the potential adverse effects of masks on humans and aquatic organisms, advocating to enhance proper use and rational disposal for masks.
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Affiliation(s)
- Shuai Tang
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Qun Zhang
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; School of Public Health, Shandong Second Medical University, Weifang 261053, China
| | - Haowen Xu
- School of Life Sciences, The Chinese University of Hong Kong, 999077, Hong Kong, China
| | - Mengyuan Zhu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Md Nahid Pervez
- Department of Environmental and Sustainable Engineering, University at Albany, State University of New York, Albany, NY 12222, USA
| | - Bing Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Yaping Zhao
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area of Ministry of Natural Resources, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, Institute of Eco-Chongming and School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China.
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Aer L, Jiang Q, Zhong L, Si Q, Liu X, Pan Y, Feng J, Zeng H, Tang L. Optimization of polyethylene terephthalate biodegradation using a self-assembled multi-enzyme cascade strategy. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:134887. [PMID: 38901251 DOI: 10.1016/j.jhazmat.2024.134887] [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: 02/04/2024] [Revised: 06/04/2024] [Accepted: 06/10/2024] [Indexed: 06/22/2024]
Abstract
Although many efforts have been devoted to the modification of polyethylene terephthalate (PET) hydrolases for improving the efficiency of PET degradation, the catalytic performance of these enzymes at near-ambient temperatures remains a challenge. Herein, a multi-enzyme cascade system (PT-EC) was developed and validated by assembling three well-developed PETases, PETaseEHA, Fast-PETase, and Z1-PETase, respectively, together with carboxylesterase TfCa, and hydrophobic binding module CBM3a using scaffold proteins. The resulting PT-ECEHA, PT-ECFPE, PT-ECZPE all demonstrated outstanding PET degradation efficacy. Notably, PT-ECEHA exhibited a 16.5-fold increase in product release compared to PETaseEHA, and PT-ECZPE yielded the highest amount of product. Subsequently, PT-ECs were displayed on the surface of Escherichia coli, respectively, and their degradation efficiency toward three PET types was investigated. The displayed PT-ECEHA exhibited a 20-fold increase in degradation efficiency with PET film compared to the surface-displayed PETaseEHA. Remarkably, an almost linear increase in product release was observed for the displayed PT-ECZPE over a one-week degradation period, reaching 11.56 ± 0.64 mM after 7 days. TfCaI69W/L281Y evolved using a docking-based virtual screening strategy showed a further 2.5-fold increase in the product release of PET degradation. Collectively, these advantages of PT-EC demonstrated the potential of a multi-enzyme cascade system for PET bio-cycling.
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Affiliation(s)
- Lizhu Aer
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Qifa Jiang
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Linling Zhong
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Qiuyue Si
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Xianghong Liu
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Yan Pan
- Medical School of University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Juan Feng
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China; Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Hongjuan Zeng
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China; Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Lixia Tang
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China; Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu 610054, China.
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Du M, Xue R, Yuan W, Cheng Y, Cui Z, Dong W, Qiu B. Tandem Integration of Biological and Electrochemical Catalysis for Efficient Polyester Upcycling under Ambient Conditions. NANO LETTERS 2024; 24:9768-9775. [PMID: 39057181 DOI: 10.1021/acs.nanolett.4c02966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Excessive production of waste polyethylene terephthalate (PET) poses an ecological challenge, which necessitates developing technologies to extract the values from end-of-life PET. Upcycling has proven effective in addressing the low profitability of current recycling strategies, yet existing upcycling technologies operate under energy-intensive conditions. Here we report a cascade strategy to steer the transformation of PET waste into glycolate in an overall yield of 92.6% under ambient conditions. The cascade approach involves setting up a robust hydrolase with 95.6% PET depolymerization into ethylene glycol (EG) monomer within 12 h, followed by an electrochemical process initiated by a CO-tolerant Pd/Ni(OH)2 catalyst to convert the EG intermediate into glycolate with high Faradaic efficiency of 97.5%. Techno-economic analysis and life cycle assessment indicate that, compared with the widely adopted electrochemical technology that heavily relies on alkaline pretreatment for PET depolymerization, our designed enzymatic-electrochemical approach offers a cost-effective and low-carbon pathway to upgrade PET.
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Affiliation(s)
- Mengmeng Du
- Jiangsu Key Laboratory of Pesticide Sciences, Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Rui Xue
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Wenfang Yuan
- Jiangsu Key Laboratory of Pesticide Sciences, Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Yun Cheng
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Zhongli Cui
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Weiliang Dong
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Bocheng Qiu
- Jiangsu Key Laboratory of Pesticide Sciences, Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
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Zheng M, Li Y, Dong W, Zhang Q, Wang W. Regioselective enzymatic depolymerization of aromatic-aliphatic polyester revealed by computational modelling. JOURNAL OF HAZARDOUS MATERIALS 2024; 474:134797. [PMID: 38865921 DOI: 10.1016/j.jhazmat.2024.134797] [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: 03/15/2024] [Revised: 05/25/2024] [Accepted: 06/01/2024] [Indexed: 06/14/2024]
Abstract
Poly(butylene adipate-co-terephthalate) (PBAT) is widely utilized in the production of food packaging and mulch films. Its extensive application has contributed significantly to global solid waste, posing numerous environmental challenges. Recently, enzymatic recycling has emerged as a promising eco-friendly solution for the management of plastic waste. Here, we systematically investigate the depolymerization mechanism of PBAT catalyzed by cutinase TfCutSI with molecular docking, molecular dynamics simulations, and quantum mechanics/molecular mechanics calculations. Although the binding affinities for acid ester and terephthalic acid ester bonds are similar, a regioselective depolymerization mechanism and a "chain-length" effect on regioselectivity were proposed and evidenced. The regioselectivity is highly associated with specific structural parameters, namely Substrate@O4-Met@H7 and Substrate@C1-Ser@O1 distances. Notably, the binding mode of BTa captured by X-ray crystallography does not facilitate subsequent depolymerization. Instead, a previously unanticipated binding mode, predicted through computational analysis, is confirmed to play a crucial role in BTa depolymerization. This finding proves the critical role of computational modelling in refining experimental results. Furthermore, our results revealed that both the hydrogen bond network and enzyme's intrinsic electric field are instrumental in the formation of the final product. In summary, these novel molecular insights into the PBAT depolymerization mechanism offer a fundamental basis for enzyme engineering to enhance industrial plastic recycling.
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Affiliation(s)
- Mingna Zheng
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Yanwei Li
- Environment Research Institute, Shandong University, Qingdao 266237, PR China.
| | - Weiliang Dong
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China
| | - Qingzhu Zhang
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Wenxing Wang
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
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Kaushik A, Singh A, Kumar Gupta V, Mishra YK. Nano/micro-plastic, an invisible threat getting into the brain. CHEMOSPHERE 2024; 361:142380. [PMID: 38763401 DOI: 10.1016/j.chemosphere.2024.142380] [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: 03/25/2024] [Revised: 05/16/2024] [Accepted: 05/17/2024] [Indexed: 05/21/2024]
Abstract
Due to weather and working/operational conditions, plastic degradation produces toxic and non-biodegradable nano and microplastics (N/M-Ps, ranging from 10 nm to 5 mm), and over time these N/M-Ps have integrated with the human cycle through ingestion and inhalation. These N/M-Ps, as serious emerging pollutants, are causing considerable adverse health issues due to up-taken by the cells, tissue, and organs, including the brain. It has been proven that N/M-Ps can cross the blood-brain barrier (via olfactory and blood vessels) and affect the secretion of neuroinflammatory (cytokine and chemokine), transporters, and receptor markers. Neurotoxicity, neuroinflammation, and brain injury, which may result in such scenarios are a serious concern and may cause brain disorders. However, the related pathways and pathogenesis are not well-explored but are the focus of upcoming emerging research. Therefore, as a focus of this editorial, well-organized multidisciplinary research is required to explore associated pathways and pathogenesis, leading to brain mapping and nano-enabled therapeutics in acute and chronic N/M - Ps exposure.
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Affiliation(s)
- Ajeet Kaushik
- NanoBioTech Laboratory, Department of Environmental Engineering, Florida Polytechnic University, Lakeland, FL, USA.
| | - Avtar Singh
- Research and Development, Molekule Inc., 3802 Spectrum Blvd., Tampa, FL, 33612, USA.
| | - V Kumar Gupta
- School of Biotechnology, Dublin City University, Dublin, Ireland.
| | - Yogendra Kumar Mishra
- Mads Clausen Institute, NanoSYD, University of Southern Denmark, Alsion 2, 6400, Sønderborg, Denmark.
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Ercolano C, Iacono R, Cafaro V, Pizzo E, Giovannelli D, Feuerriegel G, Streit WR, Strazzulli A, Moracci M. Biochemical Characterisation of Sis: A Distinct Thermophilic PETase with Enhanced NanoPET Substrate Hydrolysis and Thermal Stability. Int J Mol Sci 2024; 25:8120. [PMID: 39125688 PMCID: PMC11311821 DOI: 10.3390/ijms25158120] [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: 05/27/2024] [Revised: 07/12/2024] [Accepted: 07/23/2024] [Indexed: 08/12/2024] Open
Abstract
Polyethylene terephthalate (PET) degradation by enzymatic hydrolysis is significant for addressing plastic pollution and fostering sustainable waste management practices. Identifying thermophilic and thermostable PET hydrolases is particularly crucial for industrial bioprocesses, where elevated temperatures may enhance enzymatic efficiency and process kinetics. In this study, we present the discovery of a novel thermophilic and thermostable PETase enzyme named Sis, obtained through metagenomic sequence-based analysis. Sis exhibits robust activity on nanoPET substrates, demonstrating effectiveness at temperatures up to 70 °C and displaying exceptional thermal stability with a melting temperature (Tm) of 82 °C. Phylogenetically distinct from previously characterised PET hydrolases, Sis represents a valuable addition to the repertoire of enzymes suitable for PET degradation.
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Affiliation(s)
- Carmen Ercolano
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, Via Cinthia 21, 80126 Naples, Italy; (C.E.); (R.I.); (V.C.); (E.P.); (D.G.); (M.M.)
| | - Roberta Iacono
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, Via Cinthia 21, 80126 Naples, Italy; (C.E.); (R.I.); (V.C.); (E.P.); (D.G.); (M.M.)
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy
| | - Valeria Cafaro
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, Via Cinthia 21, 80126 Naples, Italy; (C.E.); (R.I.); (V.C.); (E.P.); (D.G.); (M.M.)
| | - Elio Pizzo
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, Via Cinthia 21, 80126 Naples, Italy; (C.E.); (R.I.); (V.C.); (E.P.); (D.G.); (M.M.)
- Centro Servizi Metrologici e Tecnologici Avanzati (CeSMA), University of Naples Federico II, 80126 Naples, Italy
| | - Donato Giovannelli
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, Via Cinthia 21, 80126 Naples, Italy; (C.E.); (R.I.); (V.C.); (E.P.); (D.G.); (M.M.)
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy
- Institute for Marine Biological Resources and Biotechnologies, Italian National Research Council, CNR-IRBIM, 60125 Ancona, Italy
- Department of Marine and Coastal Science, Rutgers University, New Brunswick, NJ 08901, USA
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
- Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, Tokyo 152-8552, Japan
| | - Golo Feuerriegel
- Department of Microbiology and Biotechnology, University of Hamburg, 22609 Hamburg, Germany; (G.F.); (W.R.S.)
| | - Wolfgang R. Streit
- Department of Microbiology and Biotechnology, University of Hamburg, 22609 Hamburg, Germany; (G.F.); (W.R.S.)
| | - Andrea Strazzulli
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, Via Cinthia 21, 80126 Naples, Italy; (C.E.); (R.I.); (V.C.); (E.P.); (D.G.); (M.M.)
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy
| | - Marco Moracci
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, Via Cinthia 21, 80126 Naples, Italy; (C.E.); (R.I.); (V.C.); (E.P.); (D.G.); (M.M.)
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy
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Huang X, Li Y, Shu Z, Huang L, Liu Q, Jiang G. High-Efficiency Degradation of PET Plastics by Glutathione S-Transferase under Mild Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 39012182 DOI: 10.1021/acs.est.4c02132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Plastic pollution is a significant environmental concern globally. Plastics are normally considered chemically inert and resistant to biodegradation. Although many papers have reported enzyme-induced biodegradation of plastics, these studies are primarily limited to enzymes of microbial origin or engineered enzymes. This study reveals that poly(ethylene terephthalate) (PET, ∼6000 Da and 100 kDa) particles and plastic bottle debris (PBD, 24.9 kDa) can be efficiently degraded by a mammal-origin natural phase II metabolic isozyme, glutathione S-transferase (GST), under mild conditions. The degradation efficiency of PET plastics reached 98.9%, with a degradation rate of 2.6 g·L-1·h-1 under ambient or physiological conditions at 1 atm. PET plastics can be degraded by GST with varying environmental or biological factors (i.e., temperature, light irradiation, pH, and presence of humic acid or protein). We suggest a novel mechanism for PET degradation other than hydrolysis, i.e., the mechanism of cleavage and release of PET plastic monomers via nitridation and oxidation. This finding also reveals a novel function of GST, previously thought to only degrade small molecules (<1000 Da). This method has been successfully applied in real human serum samples. Additionally, we have tested and confirmed the ability to degrade PET of a mammal-origin natural digestive enzyme (trypsin) and a human-derived natural metabolic enzyme (CYP450). Overall, our findings provide a potential new route to plastic pollution control and contribute to our understanding of the metabolism and fate of plastics in organisms.
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Affiliation(s)
- Xiu Huang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu 610041, China
| | - Yong Li
- College of Life Science and Technology, Central South University of Forestry and Technology, Changsha 410004, China
| | - Zhao Shu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100190, China
| | - Li Huang
- West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu 610041, China
| | - Qian Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100190, China
- Institute of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100190, China
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10
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Qin W, Zhang L, Yang Y, Zhou W, Hou S, Huang J, Gao B. Rational design of short-chain dehydrogenase DHDR for efficient synthesis of (S)-equol. Enzyme Microb Technol 2024; 180:110480. [PMID: 39067324 DOI: 10.1016/j.enzmictec.2024.110480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 06/08/2024] [Accepted: 07/14/2024] [Indexed: 07/30/2024]
Abstract
(S)-equol, the most influential metabolite of daidzein in vivo, has aroused great attention due to the excellent biological activities. Although existing studies have accomplished the construction of its heterologous synthetic pathway in the context of anaerobicity and inefficiency of natural strains, the low productivity of (S)-equol limits its industrial application. Here, rational design strategies based on decreasing the pocket steric hindrance and fine-tuning the pocket microenvironment to systematically redesign the binding pocket of enzyme were developed and processed to the rate-limiting enzyme dihydrodaidzein reductase in (S)-equol synthesis. After iterative combinatorial mutagenesis, an effective mutant S118G/T169A capable of significantly increasing (S)-equol yield was obtained. Computational analyses illustrated that the main reason of the increased activity relied on the decreased critical distance and more stable interacting conformation. Then, the reaction optimization was performed, and the recombinant Escherichia coli whole-cell biocatalyst harboring S118G/T169A enabled the efficient conversion of 2 mM daidzein to (S)-equol, achieving conversion rate of 84.5 %, which was 2.9 times higher than that of the parental strain expressing wide type dihydrodaidzein reductase. This study provides an effective idea and a feasible method for enzyme modification and whole-cell catalytic synthesis of (S)-equol, and will greatly accelerate the process of industrial production.
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Affiliation(s)
- Weichuang Qin
- State Key of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China
| | - Lujia Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Yichen Yang
- State Key of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China
| | - Wei Zhou
- State Key of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China
| | - Shuting Hou
- State Key of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China
| | - Jie Huang
- State Key of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China
| | - Bei Gao
- State Key of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China.
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11
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Tian R, Guan M, Chen L, Wan Y, He L, Zhao Z, Gao T, Zong L, Chang J, Zhang J. Mechanism insights into the histopathological changes of polypropylene microplastics induced gut and liver in zebrafish. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 280:116537. [PMID: 38852469 DOI: 10.1016/j.ecoenv.2024.116537] [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: 04/17/2024] [Revised: 05/20/2024] [Accepted: 05/30/2024] [Indexed: 06/11/2024]
Abstract
Microplastics (MPs), emerging as significant pollutants, have been consistently detected in aquatic environments, with the Yangtze River experiencing a particularly severe level of microplastic pollution, exceeding all other watersheds in China. Polypropylene (PP), the plastic most abundantly found in the middle and lower reaches of the Yangtze River Basin, has less comprehensive research results into its toxic effects. Consequently, the present investigation employed zebrafish as a model organism to delve into the toxicological impacts of polypropylene microplastics (PP-MPs) with a diameter of 5 μm across varying concentrations (300 mg/L and 600 mg/L). Using histopathological, microbiota profiling, and transcriptomic approaches, we systematically evaluated the impact of PP-MPs exposure on the intestine and liver of zebrafish. Histopathological analysis revealed that exposure to PP-MPs resulted in thinner intestinal walls, damaged intestinal mucosa, and hepatic cellular damage. Intestinal microbiota profiling demonstrated that, the richness, uniformity, diversity, and homogeneity of gut microbes significantly increased after the PP-MPs exposure at high concentration. These alterations were accompanied by shifts in the relative abundance of microbiota associated with intestinal pathologies, suggesting a profound impact on the intestinal microbial community structure. Concurrently, hepatic transcriptome analysis and RT-qPCR indicated that the downregulation of pathways and genes associated with cell proliferation regulation and DNA damage repair mechanisms contributed to hepatic cellular damage, ultimately exerting adverse effects on the liver. Correlation analysis between the intestinal microbiota and liver transcriptome profiles further highlighted significant associations between intestinal microbiota and the downregulated hepatic pathways. Collectively, these results provide novel insights into the subacute toxicological mechanisms of PP-MPs in aquatic organisms and highlight the need for further research on the ecological and health risks associated with PP-MPs pollution.
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Affiliation(s)
- Ran Tian
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Miao Guan
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Lei Chen
- Department of Thoracic Surgery, the Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Yaming Wan
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Le He
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Ziwen Zhao
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Ting Gao
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Linhao Zong
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Jiang Chang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Junfeng Zhang
- School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210000, China.
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12
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Li A, Wu L, Cui H, Song Y, Zhang X, Li X. Unlocking a Sustainable Future for Plastics: A Chemical-Enzymatic Pathway for Efficient Conversion of Mixed Waste to MHET and Energy-Saving PET Recycling. CHEMSUSCHEM 2024; 17:e202301612. [PMID: 38385577 DOI: 10.1002/cssc.202301612] [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: 01/04/2024] [Revised: 02/21/2024] [Accepted: 02/21/2024] [Indexed: 02/23/2024]
Abstract
The heterogeneous monomers obtained from plastic waste degradation are unfavorable for PET recondensation and high-value derivative synthesis. Herein, we developed an efficient chemical-enzymatic approach to convert mixed plastic wastes into homogeneous mono-2-hydroxyethyl terephthalate (MHET) without downstream purification, benefiting from three discovered BHETases (KbEst, KbHyd, and BrevEst) in nature. Towards the mixed plastic waste, integrating the chemical K2CO3-driven glycolysis process with the BHETase depolymerization technique resulted in an MHET yield of up to 98.26 % in 40 h. Remarkably, BrevEst accomplished the highest BHET hydrolysis (~87 % efficiency in 12 h) for yielding analytical-grade MHET compared to seven state-of-the-art PET hydrolases (18 %-40 %). In an investigation combining quantum theoretical computations and experimental validations, we established a MHET-initiated PET repolymerization pathway. This shortcut approach with MHET promises to strengthen the valorization of mixed plastics, offering a substantially more efficient and energy-saving route for PET recycling.
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Affiliation(s)
- Anni Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Luxuan Wu
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Haiyang Cui
- School of Life Sciences, Nanjing Normal University, Nanjing, People's Republic of China
| | - Yibo Song
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Xing Zhang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
| | - Xiujuan Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210009, People's Republic of China
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13
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Chen H, Huang D, Zhou W, Deng R, Yin L, Xiao R, Li S, Li F, Lei Y. Hotspots lurking underwater: Insights into the contamination characteristics, environmental fates and impacts on biogeochemical cycling of microplastics in freshwater sediments. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:135132. [PMID: 39002483 DOI: 10.1016/j.jhazmat.2024.135132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 06/19/2024] [Accepted: 07/05/2024] [Indexed: 07/15/2024]
Abstract
The widespread presence of microplastics (MPs) in aquatic environments has become a significant concern, with freshwater sediments acting as terminal sinks, rapidly picking up these emerging anthropogenic particles. However, the accumulation, transport, degradation and biochemical impacts of MPs in freshwater sediments remain unresolved issues compared to other environmental compartments. Therefore, this paper systematically revealed the spatial distribution and characterization information of MPs in freshwater (rivers, lakes, and estuaries) sediments, in which small-size (<1 mm), fibers, transparent, polyethylene (PE), and polypropylene (PP) predominate, and the average abundance of MPs in river sediments displayed significant heterogeneity compared to other matrices. Next, the transport kinetics and drivers of MPs in sediments are summarized, MPs transport is controlled by the particle diversity and surrounding environmental variability, leading to different migration behaviors and transport efficiencies. Also emphasized the spatio-temporal evolution of MPs degradation processes and biodegradation mechanisms in sediments, different microorganisms can depolymerize high molecular weight polymers into low molecular weight biodegradation by-products via secreting hydrolytic enzymes or redox enzymes. Finally, discussed the ecological impacts of MPs on microbial-nutrient coupling in sediments, MPs can interfere with the ecological balance of microbially mediated nutrient cycling by altering community networks and structures, enzyme activities, and nutrient-related functional gene expressions. This work aims to elucidate the plasticity characteristics, fate processes, and potential ecological impact mechanisms of MPs in freshwater sediments, facilitating a better understanding of environmental risks of MPs in freshwater sediments.
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Affiliation(s)
- Haojie Chen
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Danlian Huang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China; Greater Bay Area Institute for Innovation, Hunan University, Guangzhou 511300, Guangdong, PR China.
| | - Wei Zhou
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Rui Deng
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Lingshi Yin
- College of Water Resources & Civil Engineering, Hunan Agricultural University, Changsha 410128, PR China
| | - Ruihao Xiao
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Sai Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Fei Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Yang Lei
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
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14
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Bornscheuer UT. Concluding remarks: biocatalysis. Faraday Discuss 2024. [PMID: 38958033 DOI: 10.1039/d4fd00127c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Biocatalysis is a rapidly evolving field with increasing impact in organic synthesis, chemical manufacturing and medicine. The Faraday Discussion reflected the current state of biocatalysis, covering the design of de novo enzymatic activities, but especially methods for the improvement of enzymes targeting a broad range of applications (i.e., hydroxylations by P450 monooxygenases, enzymatic deprotection of organic compounds under mild conditions, synthesis of chiral intermediates, plastic degradation, silicone polymer synthesis, and peptide synthesis). Central themes have been how to improve an enzyme using methods of rational design and directed evolution, informed by computer modelling and machine learning, and the incorporation of new catalytic functionalities to create hybrid and artificial enzymes.
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Affiliation(s)
- Uwe T Bornscheuer
- Department of Biotechnology & Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17489 Greifswald, Germany.
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15
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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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16
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Denton MR, Murphy NP, Norton-Baker B, Lua M, Steel H, Beckham GT. Integration of pH Control into Chi.Bio Reactors and Demonstration with Small-Scale Enzymatic Poly(ethylene terephthalate) Hydrolysis. Biochemistry 2024; 63:1599-1607. [PMID: 38907702 PMCID: PMC11223484 DOI: 10.1021/acs.biochem.4c00149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2024] [Revised: 06/05/2024] [Accepted: 06/05/2024] [Indexed: 06/24/2024]
Abstract
Small-scale bioreactors that are affordable and accessible would be of major benefit to the research community. In previous work, an open-source, automated bioreactor system was designed to operate up to the 30 mL scale with online optical monitoring, stirring, and temperature control, and this system, dubbed Chi.Bio, is now commercially available at a cost that is typically 1-2 orders of magnitude less than commercial bioreactors. In this work, we further expand the capabilities of the Chi.Bio system by enabling continuous pH monitoring and control through hardware and software modifications. For hardware modifications, we sourced low-cost, commercial pH circuits and made straightforward modifications to the Chi.Bio head plate to enable continuous pH monitoring. For software integration, we introduced closed-loop feedback control of the pH measured inside the Chi.Bio reactors and integrated a pH-control module into the existing Chi.Bio user interface. We demonstrated the utility of pH control through the small-scale depolymerization of the synthetic polyester, poly(ethylene terephthalate) (PET), using a benchmark cutinase enzyme, and compared this to 250 mL bioreactor hydrolysis reactions. The results in terms of PET conversion and rate, measured both by base addition and product release profiles, are statistically equivalent, with the Chi.Bio system allowing for a 20-fold reduction of purified enzyme required relative to the 250 mL bioreactor setup. Through inexpensive modifications, the ability to conduct pH control in Chi.Bio reactors widens the potential slate of biochemical reactions and biological cultivations for study in this system, and may also be adapted for use in other bioreactor platforms.
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Affiliation(s)
- Mackenzie
C. R. Denton
- Renewable
Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
- BOTTLE
Consortium, Golden, Colorado 80401, United States
| | - Natasha P. Murphy
- Renewable
Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
- BOTTLE
Consortium, Golden, Colorado 80401, United States
| | - Brenna Norton-Baker
- Renewable
Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
- BOTTLE
Consortium, Golden, Colorado 80401, United States
| | - Mauro Lua
- Catalytic
Carbon Transformation and Scale-up Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Harrison Steel
- Department
of Engineering Science, University of Oxford, Oxford OX1 3PJ, U.K.
| | - Gregg T. Beckham
- Renewable
Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
- BOTTLE
Consortium, Golden, Colorado 80401, United States
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17
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Ji L, Meng J, Li C, Wang M, Jiang X. From Polyester Plastics to Diverse Monomers via Low-Energy Upcycling. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2403002. [PMID: 38626364 PMCID: PMC11220695 DOI: 10.1002/advs.202403002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 03/31/2024] [Indexed: 04/18/2024]
Abstract
Polyester plastics, constituting over 10% of the total plastic production, are widely used in packaging, fiber, single-use beverage bottles, etc. However, their current depolymerization processes face challenges such as non-broad spectrum recyclability, lack of diversified high-value-added depolymerization products, and crucially high energy consumption. Herein, an efficient strategy is developed for dismantling the compact structure of polyester plastics to achieve diverse monomer recovery. Polyester plastics undergo swelling and decrystallization with a low depolymerization energy barrier via synergistic effects of polyfluorine/hydrogen bonding, which is further demonstrated via density functional theory calculations. The swelling process is elucidated through scanning electron microscopy analysis. Obvious destruction of the crystalline region is demonstrated through X-ray crystal diffractometry curves. PET undergoes different aminolysis efficiently, yielding nine corresponding high-value-added monomers via low-energy upcycling. Furthermore, four types of polyester plastics and five types of blended polyester plastics are closed-loop recycled, affording diverse monomers with exceeding 90% yields. Kilogram-scale depolymerization of real polyethylene terephthalate (PET) waste plastics is successfully achieved with a 96% yield.
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Affiliation(s)
- Lei Ji
- State Key Laboratory of Molecular & Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal UniversityNorth Zhongshan Road 3663Shanghai200062China
| | - Jiaolong Meng
- State Key Laboratory of Molecular & Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal UniversityNorth Zhongshan Road 3663Shanghai200062China
| | - Chengliang Li
- State Key Laboratory of Molecular & Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal UniversityNorth Zhongshan Road 3663Shanghai200062China
| | - Ming Wang
- State Key Laboratory of Molecular & Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal UniversityNorth Zhongshan Road 3663Shanghai200062China
| | - Xuefeng Jiang
- State Key Laboratory of Molecular & Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal UniversityNorth Zhongshan Road 3663Shanghai200062China
- School of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007China
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18
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Ramírez O, Lopéz-Frances A, Baldoví HG, Saldías C, Navalón S, Leiva A, Díaz DD. Hydrogel composites based on chitosan and CuAuTiO 2 photocatalysts for hydrogen production under simulated sunlight irradiation. Int J Biol Macromol 2024; 273:132898. [PMID: 38844280 DOI: 10.1016/j.ijbiomac.2024.132898] [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: 02/08/2024] [Revised: 05/16/2024] [Accepted: 06/02/2024] [Indexed: 06/22/2024]
Abstract
This study explored the photocatalytic hydrogen evolution reaction (HER) using novel biohydrogel composites comprising chitosan, and a photocatalyst consisting in TiO2 P25 decorated with Au and/or Cu mono- and bimetallic nanoparticles (NPs) to boost its optical and catalytic properties. Low loads of Cu and Au (1 mol%) were incorporated onto TiO2 via a green photodeposition methodology. Characterization techniques confirmed the incorporation of decoration metals as well as improvements in the light absorption properties in the visible light interval (λ > 390 nm) and electron transfer capability of the semiconductors. Thereafter, Au and/or Cu NP-supported TiO2 were incorporated into chitosan-based physically crosslinked hydrogels revealing significant interactions between chitosan functional groups (hydroxyls, amines and amides) with the NPs to ensure its encapsulation. These materials were evaluated as photocatalysts for the HER using water and methanol mixtures under simulated sunlight and visible light irradiation. Sample CuAuTiO2/ChTPP exhibited a maximum hydrogen generation of 1790 μmol g-1 h-1 under simulated sunlight irradiation, almost 12-folds higher compared with TiO2/ChTPP. Also, the nanocomposites revealed a similar tendency under visible light with a maximum hydrogen production of 590 μmol g-1 h-1. These results agree with the efficiency of photoinduced charge separation revealed by transient photocurrent and EIS.
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Affiliation(s)
- Oscar Ramírez
- Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Antón Lopéz-Frances
- Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, Valencia 46022, Spain
| | - Herme G Baldoví
- Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, Valencia 46022, Spain
| | - César Saldías
- Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Sergio Navalón
- Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, Valencia 46022, Spain
| | - Angel Leiva
- Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - David Díaz Díaz
- Departamento de Química Orgánica, Universidad de la Laguna, La Laguna 38206, Spain; Instituto Universitario de Bio-Orgánica, Universidad de la Laguna, La Laguna 38206, Spain.
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19
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Charlier C, Gavalda S, Grga J, Perrot L, Gabrielli V, Löhr F, Schörghuber J, Lichtenecker R, Arnal G, Marty A, Tournier V, Lippens G. Exploring the pH dependence of an improved PETase. Biophys J 2024; 123:1542-1552. [PMID: 38664965 PMCID: PMC11213969 DOI: 10.1016/j.bpj.2024.04.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/20/2024] [Accepted: 04/23/2024] [Indexed: 05/12/2024] Open
Abstract
Enzymatic recycling of plastic and especially of polyethylene terephthalate (PET) has shown great potential to reduce its negative impact on our society. PET hydrolases (PETases) have been optimized using rational design and machine learning, but the mechanistic details of the PET depolymerization process remain unclear. Belonging to the carboxylic-ester hydrolase family with a canonical Ser-His-Asp catalytic triad, their observed alkaline pH optimum is generally thought to be related to the protonation state of the catalytic His. Here, we explore this aspect in the context of LCCICCG, an optimized PETase, derived from the leaf-branch compost cutinase enzyme. We use NMR to identify the dominant tautomeric structure of the six histidines. Five show surprisingly low pKa values below 4.0, whereas the catalytic H242 in the active enzyme displays a pKa value that varies from 4.9 to 4.7 when temperatures increase from 30°C to 50°C. Whereas the hydrolytic activity of the enzyme toward a soluble substrate can be modeled by the corresponding protonation/deprotonation curve, an important discrepancy is found when the substrate is the solid plastic. This opens the way to further mechanistic understanding of the PETase activity and underscores the importance of studying the enzyme at the liquid-solid interface.
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Affiliation(s)
- Cyril Charlier
- Toulouse Biotechnology Institute (TBI), University of Toulouse, CNRS, INRAE, INSA Toulouse, Toulouse Cedex, France
| | - Sabine Gavalda
- Carbios, Parc Cataroux - Bâtiment B80, Clermont-Ferrand, France
| | - Jelena Grga
- Toulouse Biotechnology Institute (TBI), University of Toulouse, CNRS, INRAE, INSA Toulouse, Toulouse Cedex, France
| | - Laura Perrot
- Toulouse Biotechnology Institute (TBI), University of Toulouse, CNRS, INRAE, INSA Toulouse, Toulouse Cedex, France
| | - Valeria Gabrielli
- Toulouse Biotechnology Institute (TBI), University of Toulouse, CNRS, INRAE, INSA Toulouse, Toulouse Cedex, France
| | - Frank Löhr
- Institute of Biophysical Chemistry, Center for Biomolecular Magnetic Resonance, Goethe, University Frankfurt, Frankfurt am Main, Germany
| | - Julia Schörghuber
- Institute of Organic Chemistry, University of Vienna, Währingerstraße 38, Vienna, Austria
| | - Roman Lichtenecker
- Institute of Organic Chemistry, University of Vienna, Währingerstraße 38, Vienna, Austria; MAG-LAB, Vienna, Austria
| | - Grégory Arnal
- Carbios, Parc Cataroux - Bâtiment B80, Clermont-Ferrand, France
| | - Alain Marty
- Carbios, Parc Cataroux - Bâtiment B80, Clermont-Ferrand, France
| | | | - Guy Lippens
- Toulouse Biotechnology Institute (TBI), University of Toulouse, CNRS, INRAE, INSA Toulouse, Toulouse Cedex, France.
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20
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Taxeidis G, Nikolaivits E, Nikodinovic-Runic J, Topakas E. Mimicking the enzymatic plant cell wall hydrolysis mechanism for the degradation of polyethylene terephthalate. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 356:124347. [PMID: 38857840 DOI: 10.1016/j.envpol.2024.124347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 06/06/2024] [Accepted: 06/07/2024] [Indexed: 06/12/2024]
Abstract
Plastic pollution presents a global challenge, impacting ecosystems, wildlife, and economies. Polyethylene terephthalate (PET), widely used in products like bottles, significantly contributes to this issue due to poor waste collection. In recent years, there has been increasing interest in plant biomass-degrading enzymes for plastic breakdown, due to the structural and physicochemical similarities between natural and synthetic polymers. Filamentous fungi involved in hemicellulose degradation have developed a complex mode of action that includes not only enzymes but also biosurfactants; surface-active molecules that facilitate enzyme-substrate interactions. For this reason, this study aimed to mimic the mechanism of biomass degradation by repurposing plant cell wall degrading enzymes including a cutinase and three esterases to cooperatively contribute to PET degradation. Surfactants of different charge were also introduced in the reactions, as their role is similar to biosurfactants, altering the surface tension of the polymers and thus improving enzymes' accessibility. Notably, Fusarium oxysporum cutinase combined with anionic surfactant exhibited a 2.3- and 1.6-fold higher efficacy in hydrolyzing amorphous and semi-crystalline PET, respectively. When cutinase was combined with either of two ferulic acid esterases, it resulted in complete conversion of PET intermediate products to TPA, increasing the overall product release up to 1.9- fold in presence of surfactant. The combination of cutinase with a glucuronoyl esterase demonstrated significant potential in plastic depolymerization, increasing degradation yields in semi-crystalline PET by up to 1.4-fold. The approach of incorporating enzyme cocktails and surfactants emerge as an efficient solution for PET degradation in mild reaction conditions, with potential applications in eco-friendly plastic waste management.
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Affiliation(s)
- George Taxeidis
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Heroon Polytechniou 9, Zografou, 15772, Athens, Greece
| | - Efstratios Nikolaivits
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Heroon Polytechniou 9, Zografou, 15772, Athens, Greece
| | - Jasmina Nikodinovic-Runic
- Eco-Biotechnology & Drug Development Group, Laboratory for Microbial Molecular Genetics and Ecology, Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, 11000, Belgrade, Serbia
| | - Evangelos Topakas
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Heroon Polytechniou 9, Zografou, 15772, Athens, Greece.
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21
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Bergeson AR, Silvera AJ, Alper HS. Bottlenecks in biobased approaches to plastic degradation. Nat Commun 2024; 15:4715. [PMID: 38830860 PMCID: PMC11148140 DOI: 10.1038/s41467-024-49146-8] [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: 07/29/2023] [Accepted: 05/23/2024] [Indexed: 06/05/2024] Open
Abstract
Plastic waste is an environmental challenge, but also presents a biotechnological opportunity as a unique carbon substrate. With modern biotechnological tools, it is possible to enable both recycling and upcycling. To realize a plastics bioeconomy, significant intrinsic barriers must be overcome using a combination of enzyme, strain, and process engineering. This article highlights advances, challenges, and opportunities for a variety of common plastics.
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Affiliation(s)
- Amelia R Bergeson
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Ashli J Silvera
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Hal S Alper
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, USA.
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA.
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22
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Cannon JA, Zhou Y, Qualey LT, Reynolds TB. Surface-associated residues in subtilisins contribute to poly-L-lactic acid depolymerization via enzyme adsorption. Microb Biotechnol 2024; 17:e14473. [PMID: 38877615 PMCID: PMC11178483 DOI: 10.1111/1751-7915.14473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/22/2024] [Accepted: 04/14/2024] [Indexed: 06/16/2024] Open
Abstract
Poly-L-lactic acid (PLLA) is currently the most abundant bioplastic; however, limited environmental biodegradability and few recycling options diminish its value as a biodegradable commodity. Enzymatic recycling is one strategy for ensuring circularity of PLLA, but this approach requires a thorough understanding of enzymatic mechanisms and protein engineering strategies to enhance activity. In this study, we engineer PLLA depolymerizing subtilisin enzymes originating from Bacillus species to elucidate the molecular mechanisms dictating their PLLA depolymerization activity and to improve their function. The surface-associated amino acids of two closely related subtilisin homologues originating from Bacillus subtilis (BsAprE) and Bacillus pumilus (BpAprE) were compared, as they were previously engineered to have nearly identical active sites, but still varied greatly in PLLA depolymerizing activity. Further analysis identified several surface-associated amino acids in BpAprE that lead to enhanced PLLA depolymerization activity when engineered into BsAprE. In silico protein modelling demonstrated increased enzyme surface hydrophobicity in engineered BsAprE variants and revealed a structural motif favoured for PLLA depolymerization. Experimental evidence suggests that increases in activity are associated with enhanced polymer binding as opposed to substrate specificity. These data highlight enzyme adsorption as a key factor in PLLA depolymerization by subtilisins.
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Affiliation(s)
- Jordan A Cannon
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
| | - Yue Zhou
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
| | - Luke T Qualey
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
| | - Todd B Reynolds
- Department of Microbiology, University of Tennessee at Knoxville, Knoxville, Tennessee, USA
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23
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Luo S, Wang N, Pan Y, Zheng B, Li F, Dong S. Supramolecular/Dynamic Covalent Design of High-Performance Pressure-Sensitive Adhesive from Natural Low-Molecular-Weight Compounds. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2310839. [PMID: 38225689 DOI: 10.1002/smll.202310839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 12/29/2023] [Indexed: 01/17/2024]
Abstract
Adhesive materials have played an essential role in the history of humanity. Natural adhesives composed of low-molecular-weight monomers have been overshadowed by modern petroleum-based glues. With the development of green economy, the demand for eco-friendly materials has increased. Herein, two natural biocompatible compounds, namely thioctic acid (TA) and malic acid (MA), are selected to prepare a high-performance pressure-sensitive adhesive poly[TA-MA]. This adhesive can be quantitatively obtained via a simple mixing and heating process. Poly[TA-MA] shows interesting and useful properties, including reversible flexibility, high elongation, and good self-healing, owing to its dynamic polymerization pattern and reversible cross-linking behavior. Poly[TA-MA] exhibits excellent adhesion performance under various extreme conditions, such as at low temperatures and in hot water. High values of shear strength (3.86 MPa), peel strength (7.90 N cm-1), loop tack (10.60 N cm-1), tensile strength (1.02 MPa), and shear resistance (1628 h) demonstrate the strong adhesive effect of poly[TA-MA]. Additionally, TA can be regenerated in the monomer forms from poly[TA-MA] with high recovery rate (>90%). Meanwhile, strong anti-bacterial behavior of poly[TA-MA] is recorded. This study not only reported a new pressure-sensitive adhesive but also fully displayed the feasibility of using natural small molecules to achieve robust surface adhesion.
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Affiliation(s)
- Sha Luo
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Na Wang
- Xi'an Key Laboratory of Functional Supramolecular Structure and Materials, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, China
| | - Yanjuan Pan
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Bo Zheng
- Xi'an Key Laboratory of Functional Supramolecular Structure and Materials, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, China
| | - Fenfang Li
- College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, China
| | - Shengyi Dong
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
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24
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Carr CM, Göttsch F, de Oliveira BFR, Murcia PAS, Jackson SA, Wei R, Clarke DJ, Bornscheuer UT, Dobson ADW. Identification and expression of MarCE, a marine carboxylesterase with synthetic ester-degrading activity. Microb Biotechnol 2024; 17:e14479. [PMID: 38881500 PMCID: PMC11180994 DOI: 10.1111/1751-7915.14479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/15/2024] [Accepted: 04/30/2024] [Indexed: 06/18/2024] Open
Abstract
Carboxylic ester hydrolases with the capacity to degrade polyesters are currently highly sought after for their potential use in the biological degradation of PET and other chemically synthesized polymers. Here, we describe MarCE, a carboxylesterase family protein identified via genome mining of a Maribacter sp. isolate from the marine sponge Stelligera stuposa. Based on phylogenetic analysis, MarCE and its closest relatives belong to marine-associated genera from the Cytophaga-Flavobacterium-Bacteroides taxonomic group and appear evolutionarily distinct to any homologous carboxylesterases that have been studied to date in terms of structure or function. Molecular docking revealed putative binding of BHET, a short-chain PET derivative, onto the predicted MarCE three-dimensional structure. The synthetic ester-degrading activity of MarCE was subsequently confirmed by MarCE-mediated hydrolysis of 2 mM BHET substrate, indicated by the release of its breakdown products MHET and TPA, which were measured, respectively, as 1.28 and 0.12 mM following 2-h incubation at 30°C. The findings of this study provide further insight into marine carboxylic ester hydrolases, which have the potential to display unique functional plasticity resulting from their adaptation to complex and fluctuating marine environmentsw.
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Affiliation(s)
- Clodagh M. Carr
- School of MicrobiologyUniversity College CorkCorkIreland
- SSPC‐SFI Research Centre for PharmaceuticalsUniversity College CorkCorkIreland
| | - Frederike Göttsch
- Department of Biotechnology and Enzyme Catalysis, Institute of BiochemistryUniversity of GreifswaldGreifswaldGermany
| | | | - Pedro A. Sánchez Murcia
- Laboratory of Computer‐Aided Molecular Design, Division of Medicinal Chemistry, Otto‐Loewi Research CenterMedical University of GrazGrazAustria
- BioTechMed‐GrazGrazAustria
| | - Stephen A. Jackson
- School of MicrobiologyUniversity College CorkCorkIreland
- SSPC‐SFI Research Centre for PharmaceuticalsUniversity College CorkCorkIreland
- Environmental Research InstituteUniversity College CorkCorkIreland
| | - Ren Wei
- Department of Biotechnology and Enzyme Catalysis, Institute of BiochemistryUniversity of GreifswaldGreifswaldGermany
| | - David J. Clarke
- School of MicrobiologyUniversity College CorkCorkIreland
- SSPC‐SFI Research Centre for PharmaceuticalsUniversity College CorkCorkIreland
- APC Microbiome IrelandUniversity College CorkCorkIreland
| | - Uwe T. Bornscheuer
- Department of Biotechnology and Enzyme Catalysis, Institute of BiochemistryUniversity of GreifswaldGreifswaldGermany
| | - Alan D. W. Dobson
- School of MicrobiologyUniversity College CorkCorkIreland
- SSPC‐SFI Research Centre for PharmaceuticalsUniversity College CorkCorkIreland
- Environmental Research InstituteUniversity College CorkCorkIreland
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25
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Si Q, Wang F, Ding Q, Yang W, Lin H, Xu C, Li S. Chiral Cu xCo yS-Cu zS Nanoflowers with Bioinspired Enantioselective Catalytic Performances. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2311275. [PMID: 38196019 DOI: 10.1002/smll.202311275] [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: 12/04/2023] [Indexed: 01/11/2024]
Abstract
Nanomaterials with biomimetic catalytic abilities have attracted significant attention. However, the stereoselectivity of natural enzymes determined by their unique configurations is difficult to imitate. In this work, a kind of chiral CuxCoyS-CuzS nanoflowers (L/D-Pen-NFs) is developed, using porous CuxCoyS nanoparticles (NPs) as stamens, CuzS sheets as petals, and chiral penicillamine as surface stabilizers. Compared to the natural laccase enzyme, L/D-Pen-NFs exhibit significant advantages in catalytic efficiency, stability against harsh environments, recyclability, and convenience in construction. Most importantly, they display high enantioselectivity toward chiral neurotransmitters, which is proved by L- and D-Pen-NFs' different catalytic efficiencies toward chiral enantiomers. L-Pen-NFs are more efficient in catalyzing the oxidation of L-epinephrine and L-dopamine compared with D-Pen-NFs. However, their catalytic efficiency in oxidizing L-norepinephrine and L-DOPA is lower than that of D-Pen-NFs. The reason for the difference in catalytic efficiency is the distinct binding affinities between CuxCoyS-CuzS nano-enantiomers and chiral molecules. This work can spur the development of chiral nanostructures with biomimetic functions.
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Affiliation(s)
- Qingrui Si
- International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China
| | - Fang Wang
- International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China
| | - Qi Ding
- International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China
| | - Weimin Yang
- International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China
| | - Hengwei Lin
- International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China
| | - Chuanlai Xu
- State Key Lab of Food Science and Technology, International Joint Research Laboratory for Biointerface and Biodetection School of Food Science and Technology, Jiangnan University, Wuxi, 214122, P. R. China
| | - Si Li
- International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China
- State Key Lab of Food Science and Technology, International Joint Research Laboratory for Biointerface and Biodetection School of Food Science and Technology, Jiangnan University, Wuxi, 214122, P. R. China
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26
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Zandieh M, Griffiths E, Waldie A, Li S, Honek J, Rezanezhad F, Van Cappellen P, Liu J. Catalytic and biocatalytic degradation of microplastics. EXPLORATION (BEIJING, CHINA) 2024; 4:20230018. [PMID: 38939860 PMCID: PMC11189586 DOI: 10.1002/exp.20230018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 11/21/2023] [Indexed: 06/29/2024]
Abstract
In recent years, there has been a surge in annual plastic production, which has contributed to growing environmental challenges, particularly in the form of microplastics. Effective management of plastic and microplastic waste has become a critical concern, necessitating innovative strategies to address its impact on ecosystems and human health. In this context, catalytic degradation of microplastics emerges as a pivotal approach that holds significant promise for mitigating the persistent effects of plastic pollution. In this article, we critically explored the current state of catalytic degradation of microplastics and discussed the definition of degradation, characterization methods for degradation products, and the criteria for standard sample preparation. Moreover, the significance and effectiveness of various catalytic entities, including enzymes, transition metal ions (for the Fenton reaction), nanozymes, and microorganisms are summarized. Finally, a few key issues and future perspectives regarding the catalytic degradation of microplastics are proposed.
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Affiliation(s)
- Mohamad Zandieh
- Department of ChemistryUniversity of WaterlooWaterlooOntarioCanada
- Waterloo Institute for NanotechnologyUniversity of WaterlooWaterlooOntarioCanada
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
| | - Erin Griffiths
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
- Ecohydrology Research GroupDepartment of Earth and Environmental SciencesUniversity of WaterlooWaterlooOntarioCanada
| | - Alexander Waldie
- Department of ChemistryUniversity of WaterlooWaterlooOntarioCanada
- Waterloo Institute for NanotechnologyUniversity of WaterlooWaterlooOntarioCanada
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
| | - Shuhuan Li
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
- Ecohydrology Research GroupDepartment of Earth and Environmental SciencesUniversity of WaterlooWaterlooOntarioCanada
| | - John Honek
- Department of ChemistryUniversity of WaterlooWaterlooOntarioCanada
- Waterloo Institute for NanotechnologyUniversity of WaterlooWaterlooOntarioCanada
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
| | - Fereidoun Rezanezhad
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
- Ecohydrology Research GroupDepartment of Earth and Environmental SciencesUniversity of WaterlooWaterlooOntarioCanada
| | - Philippe Van Cappellen
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
- Ecohydrology Research GroupDepartment of Earth and Environmental SciencesUniversity of WaterlooWaterlooOntarioCanada
| | - Juewen Liu
- Department of ChemistryUniversity of WaterlooWaterlooOntarioCanada
- Waterloo Institute for NanotechnologyUniversity of WaterlooWaterlooOntarioCanada
- Water InstituteUniversity of WaterlooWaterlooOntarioCanada
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27
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Pal A, Wong AR, Lamb JR. Chemically Recyclable, High Molar Mass Polyoxazolidinones via Ring-Opening Metathesis Polymerization. ACS Macro Lett 2024; 13:502-507. [PMID: 38625148 DOI: 10.1021/acsmacrolett.4c00147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
The development of robust methods for the synthesis of chemically recyclable polymers with tunable properties is necessary for the design of next-generation materials. Polyoxazolidinones (POxa), polymers with five-membered urethanes in their backbones, are an attractive target because they are strongly polar and have high thermal stability, but existing step-growth syntheses limit molar masses and methods to chemically recycle POxa to monomer are rare. Herein, we report the synthesis of high molar mass POxa via ring-opening metathesis polymerization of oxazolidinone-fused cyclooctenes. These novel polymers show <5% mass loss up to 382-411 °C and have tunable glass transition temperatures (14-48 °C) controlled by the side chain structure. We demonstrate facile chemical recycling to monomer and repolymerization despite moderately high monomer ring-strain energies, which we hypothesize are facilitated by the conformational restriction introduced by the fused oxazolidinone ring. This method represents the first chain growth synthesis of POxa and provides a versatile platform for the study and application of this emerging subclass of polyurethanes.
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Affiliation(s)
- Arpan Pal
- Department of Chemistry, University of Minnesota-Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Allison R Wong
- Department of Chemistry, University of Minnesota-Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Jessica R Lamb
- Department of Chemistry, University of Minnesota-Twin Cities, Minneapolis, Minnesota 55455, United States
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28
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Martín-González D, de la Fuente Tagarro C, De Lucas A, Bordel S, Santos-Beneit F. Genetic Modifications in Bacteria for the Degradation of Synthetic Polymers: A Review. Int J Mol Sci 2024; 25:5536. [PMID: 38791573 PMCID: PMC11121894 DOI: 10.3390/ijms25105536] [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: 03/28/2024] [Revised: 05/07/2024] [Accepted: 05/17/2024] [Indexed: 05/26/2024] Open
Abstract
Synthetic polymers, commonly known as plastics, are currently present in all aspects of our lives. Although they are useful, they present the problem of what to do with them after their lifespan. There are currently mechanical and chemical methods to treat plastics, but these are methods that, among other disadvantages, can be expensive in terms of energy or produce polluting gases. A more environmentally friendly alternative is recycling, although this practice is not widespread. Based on the practice of the so-called circular economy, many studies are focused on the biodegradation of these polymers by enzymes. Using enzymes is a harmless method that can also generate substances with high added value. Novel and enhanced plastic-degrading enzymes have been obtained by modifying the amino acid sequence of existing ones, especially on their active site, using a wide variety of genetic approaches. Currently, many studies focus on the common aim of achieving strains with greater hydrolytic activity toward a different range of plastic polymers. Although in most cases the depolymerization rate is improved, more research is required to develop effective biodegradation strategies for plastic recycling or upcycling. This review focuses on a compilation and discussion of the most important research outcomes carried out on microbial biotechnology to degrade and recycle plastics.
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Affiliation(s)
- Diego Martín-González
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain; (D.M.-G.); (A.D.L.); (S.B.)
| | - Carlos de la Fuente Tagarro
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain; (D.M.-G.); (A.D.L.); (S.B.)
| | - Andrea De Lucas
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain; (D.M.-G.); (A.D.L.); (S.B.)
| | - Sergio Bordel
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain; (D.M.-G.); (A.D.L.); (S.B.)
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Fernando Santos-Beneit
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain; (D.M.-G.); (A.D.L.); (S.B.)
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
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29
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An Y, Padermshoke A, Van Nguyen T, Takahara A. Surface Chemistry in Environmental Degradation of Polymeric Solids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:9336-9344. [PMID: 38669192 DOI: 10.1021/acs.langmuir.4c00731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2024]
Abstract
Microplastics (MPs) cause significant adverse environmental effects. To address this issue, a scientific approach for understanding the formation of MPs is essential. In this Perspective, we summarize the three typical degradation behaviors of polymeric solids from a surface chemistry perspective: chemical degradation, biodegradation, and mechanical degradation. These three degradation processes can occur consecutively or simultaneously in poorly managed polymeric materials, ultimately resulting in their disintegration into the environment. This Perspective provides valuable insights into controlling the degradation of polymeric solids and designing eco-friendly polymers for a sustainable future.
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Affiliation(s)
- Yingjun An
- Research Center for Negative Emission Technologies, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Adchara Padermshoke
- Research Center for Negative Emission Technologies, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Thinh Van Nguyen
- Research Center for Negative Emission Technologies, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Atsushi Takahara
- Research Center for Negative Emission Technologies, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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30
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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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31
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Wu Y, Hu Q, Che Y, Niu Z. Opportunities and challenges for plastic depolymerization by biomimetic catalysis. Chem Sci 2024; 15:6200-6217. [PMID: 38699266 PMCID: PMC11062090 DOI: 10.1039/d4sc00070f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 03/20/2024] [Indexed: 05/05/2024] Open
Abstract
Plastic waste has imposed significant burdens on the environment. Chemical recycling allows for repeated regeneration of plastics without deterioration in quality, but often requires harsh reaction conditions, thus being environmentally unfriendly. Enzymatic catalysis offers a promising solution for recycling under mild conditions, but it faces inherent limitations such as poor stability, high cost, and narrow substrate applicability. Biomimetic catalysis may provide a new avenue by combining high enzyme-like activity with the stability of inorganic materials. Biomimetic catalysis has demonstrated great potential in biomass conversion and has recently shown promising progress in plastic degradation. This perspective discusses biomimetic catalysis for plastic degradation from two perspectives: the imitation of the active centers and the imitation of the substrate-binding clefts. Given the chemical similarity between biomass and plastics, relevant work is also included in the discussion to draw inspiration. We conclude this perspective by highlighting the challenges and opportunities in achieving sustainable plastic recycling via a biomimetic approach.
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Affiliation(s)
- Yanfen Wu
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University Beijing 100084 China
| | - Qikun Hu
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University Beijing 100084 China
| | - Yizhen Che
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University Beijing 100084 China
| | - Zhiqiang Niu
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University Beijing 100084 China
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Bocci V, Galafassi S, Levantesi C, Crognale S, Amalfitano S, Congestri R, Matturro B, Rossetti S, Di Pippo F. Freshwater plastisphere: a review on biodiversity, risks, and biodegradation potential with implications for the aquatic ecosystem health. Front Microbiol 2024; 15:1395401. [PMID: 38699475 PMCID: PMC11064797 DOI: 10.3389/fmicb.2024.1395401] [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: 03/03/2024] [Accepted: 04/05/2024] [Indexed: 05/05/2024] Open
Abstract
The plastisphere, a unique microbial biofilm community colonizing plastic debris and microplastics (MPs) in aquatic environments, has attracted increasing attention owing to its ecological and public health implications. This review consolidates current state of knowledge on freshwater plastisphere, focussing on its biodiversity, community assembly, and interactions with environmental factors. Current biomolecular approaches revealed a variety of prokaryotic and eukaryotic taxa associated with plastic surfaces. Despite their ecological importance, the presence of potentially pathogenic bacteria and mobile genetic elements (i.e., antibiotic resistance genes) raises concerns for ecosystem and human health. However, the extent of these risks and their implications remain unclear. Advanced sequencing technologies are promising for elucidating the functions of plastisphere, particularly in plastic biodegradation processes. Overall, this review emphasizes the need for comprehensive studies to understand plastisphere dynamics in freshwater and to support effective management strategies to mitigate the impact of plastic pollution on freshwater resources.
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Affiliation(s)
- Valerio Bocci
- Water Research Institute, CNR-IRSA, National Research Council, Rome, Italy
- PhD Program in Evolutionary Biology and Ecology, Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Silvia Galafassi
- Water Research Institute, CNR-IRSA, National Research Council, Verbania, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Caterina Levantesi
- Water Research Institute, CNR-IRSA, National Research Council, Rome, Italy
| | - Simona Crognale
- Water Research Institute, CNR-IRSA, National Research Council, Rome, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Stefano Amalfitano
- Water Research Institute, CNR-IRSA, National Research Council, Rome, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Roberta Congestri
- Laboratory of Biology of Algae, Department of Biology, University of Rome “Tor Vergata”, Rome, Italy
| | - Bruna Matturro
- Water Research Institute, CNR-IRSA, National Research Council, Rome, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Simona Rossetti
- Water Research Institute, CNR-IRSA, National Research Council, Rome, Italy
| | - Francesca Di Pippo
- Water Research Institute, CNR-IRSA, National Research Council, Rome, Italy
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Horváth T, Kecskés K, Jordán Csábrádiné A, Szőri-Dorogházi E, Viskolcz B, Szőri M. Searching for the Achilles' Heel of Urethane Linkage-An Energetic Perspective. Polymers (Basel) 2024; 16:1126. [PMID: 38675045 PMCID: PMC11053941 DOI: 10.3390/polym16081126] [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: 02/06/2024] [Revised: 03/21/2024] [Accepted: 04/15/2024] [Indexed: 04/28/2024] Open
Abstract
A sudden increase in polyurethane (PU) production necessitates viable recycling methods for the waste generated. PU is one of the most important plastic materials with a wide range of applications; however, the stability of the urethane linkage is a major issue in chemical recycling. In this work, termination reactions of a model urethane molecule, namely methyl N-phenyl carbamate (MPCate), are investigated using G3MP2B3 composite quantum chemical method. Our main goal was to gain insights into the energetic profile of urethane bond termination and find an applicable chemical recycling method. Hydrogenation, hydrolysis, methanolysis, peroxidation, glycolysis, ammonolysis, reduction with methylamine and termination by dimethyl phosphite were explored in both gas and condensed phases. Out of these chemicals, degradation by H2, H2O2 and CH3NH2 revealed promising results with lower activation barriers and exergonic pathways, especially in water solvation. Implementing these effective PU recycling methods can also have significant economic benefits since the obtained products from the reactions are industrially relevant substances. For example, aniline and dimethyl carbonate could be reusable in polymer technologies serving as potential methods for circular economy. As further potential transformations, several ionizations of MPCate were also examined including electron capture and detachment, protonation/deprotonation and reaction with OH-. Alkaline digestion against the model urethane MPCate was found to be promising due to the relatively low activation energy. In an ideal case, the transformation of the urethane bond could be an enzymatic process; therefore, potential enzymes, such as lipoxygenase, were also considered for the catalysis of peroxidation, and lipases for methanolysis.
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Affiliation(s)
- Tamás Horváth
- Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros A/2, H-3515 Miskolc, Hungary; (K.K.); (A.J.C.); (E.S.-D.)
| | - Karina Kecskés
- Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros A/2, H-3515 Miskolc, Hungary; (K.K.); (A.J.C.); (E.S.-D.)
| | - Anikó Jordán Csábrádiné
- Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros A/2, H-3515 Miskolc, Hungary; (K.K.); (A.J.C.); (E.S.-D.)
| | - Emma Szőri-Dorogházi
- Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros A/2, H-3515 Miskolc, Hungary; (K.K.); (A.J.C.); (E.S.-D.)
| | - Béla Viskolcz
- Higher Education and Industrial Cooperation Centre, University of Miskolc, H-3515 Miskolc, Hungary;
| | - Milán Szőri
- Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros A/2, H-3515 Miskolc, Hungary; (K.K.); (A.J.C.); (E.S.-D.)
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34
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Salam LB. Metagenomic investigations into the microbial consortia, degradation pathways, and enzyme systems involved in the biodegradation of plastics in a tropical lentic pond sediment. World J Microbiol Biotechnol 2024; 40:172. [PMID: 38630153 DOI: 10.1007/s11274-024-03972-6] [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: 02/18/2024] [Accepted: 03/29/2024] [Indexed: 04/19/2024]
Abstract
The exploitation of exciting features of plastics for diverse applications has resulted in significant plastic waste generation, which negatively impacts environmental compartments, metabolic processes, and the well-being of aquatic ecosystems biota. A shotgun metagenomic approach was deployed to investigate the microbial consortia, degradation pathways, and enzyme systems involved in the degradation of plastics in a tropical lentic pond sediment (APS). Functional annotation of the APS proteome (ORFs) using the PlasticDB database revealed annotation of 1015 proteins of enzymes such as depolymerase, esterase, lipase, hydrolase, nitrobenzylesterase, chitinase, carboxylesterase, polyesterase, oxidoreductase, polyamidase, PETase, MHETase, laccase, alkane monooxygenase, among others involved in the depolymerization of the plastic polymers. It also revealed that polyethylene glycol (PEG), polyhydroxyalkanoates (PHA), polyhydroxybutyrate (PHB), polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polyethylene terephthalate (PET), and nylon have the highest number of annotated enzymes. Further annotation using the KEGG GhostKOALA revealed that except for terephthalate, all the other degradation products of the plastic polymers depolymerization such as glyoxylate, adipate, succinate, 1,4-butanediol, ethylene glycol, lactate, and acetaldehyde were further metabolized to intermediates of the tricarboxylic acid cycle. Taxonomic characterization of the annotated proteins using the AAI Profiler and BLASTP revealed that Pseudomonadota members dominate most plastic types, followed by Actinomycetota and Acidobacteriota. The study reveals novel plastic degraders from diverse phyla hitherto not reported to be involved in plastic degradation. This suggests that plastic pollution in aquatic environments is prevalent with well-adapted degrading communities and could be the silver lining in mitigating the impacts of plastic pollution in aquatic environments.
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Affiliation(s)
- Lateef B Salam
- Microbiology Unit, Department of Biological Sciences, Elizade University, Ilara-Mokin, Ondo State, Nigeria.
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He L, Ding J, Yang SS, Zang YN, Pang JW, Xing D, Zhang LY, Ren N, Wu WM. Molecular-Weight-Dependent Degradation of Plastics: Deciphering Host-Microbiome Synergy Biodegradation of High-Purity Polypropylene Microplastics by Mealworms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6647-6658. [PMID: 38563431 DOI: 10.1021/acs.est.3c06954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The biodegradation of polypropylene (PP), a highly persistent nonhydrolyzable polymer, by Tenebrio molitor has been confirmed using commercial PP microplastics (MPs) (Mn 26.59 and Mw 187.12 kDa). This confirmation was based on the reduction of the PP mass, change in molecular weight (MW), and a positive Δδ13C in the residual PP. A MW-dependent biodegradation mechanism was investigated using five high-purity PP MPs, classified into low (0.83 and 6.20 kDa), medium (50.40 and 108.0 kDa), and high (575.0 kDa) MW categories to access the impact of MW on the depolymerization pattern and associated gene expression of gut bacteria and the larval host. The larvae can depolymerize/biodegrade PP polymers with high MW although the consumption rate and weight losses increased, and survival rates declined with increasing PP MW. This pattern is similar to observations with polystyrene (PS) and polyethylene (PE), i.e., both Mn and Mw decreased after being fed low MW PP, while Mn and/or Mw increased after high MW PP was fed. The gut microbiota exhibited specific bacteria associations, such as Kluyvera sp. and Pediococcus sp. for high MW PP degradation, Acinetobacter sp. for medium MW PP, and Bacillus sp. alongside three other bacteria for low MW PP metabolism. In the host transcriptome, digestive enzymes and plastic degradation-related bacterial enzymes were up-regulated after feeding on PP depending on different MWs. The T. molitor host exhibited both defensive function and degradation capability during the biodegradation of plastics, with high MW PP showing a relatively negative impact on the larvae.
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Affiliation(s)
- Lei He
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Jie Ding
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Shan-Shan Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Ya-Ni Zang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Ji-Wei Pang
- CECEP Digital Technology Co., Ltd., China Energy Conservation and Environmental Protection Group, Beijing 100096, China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Lu-Yan Zhang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wei-Min Wu
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Stanford University, Stanford, California 94305, United States
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36
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Ramírez O, Bonardd S, Saldías C, Leiva A, Díaz Díaz D. Highly efficient and reusable CuAu nanoparticles supported on crosslinked chitosan hydrogels as a plasmonic catalyst for nitroarene reduction. ENVIRONMENTAL RESEARCH 2024; 247:118204. [PMID: 38224938 DOI: 10.1016/j.envres.2024.118204] [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: 11/14/2023] [Revised: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 01/17/2024]
Abstract
The synthesis of CuAu-based monometallic (MNPs) and bimetallic nanoparticles (BNPs) supported on chitosan-based hydrogels for their application as catalysts is presented. The hydrogels consisted of chitosan chains cross-linked with tripolyphosphate (TPP) in the form of beads with an approximate average diameter of 1.81 mm. The MNPs and BNPs were obtained by the adsorption of metallic ions and their subsequent reduction with hydrazine, achieving a metallic loading of 0.297 mmol per gram of dry sample, with average nanoparticle sizes that were found between 2.6 and 4.4 nm. Both processes, metal adsorption and the stabilization of the nanoparticles, are mainly attributed to the participation of chitosan hydroxyl, amine and amide functional groups. The materials revealed important absorption bands in the visible region of the light spectra, specifically between 520 and 590 nm, mainly attributed to LSPR given the nature of the MNPs and BNPs inside the hydrogels. Subsequently, the hydrogels were evaluated as catalysts against the reduction of 4-nitrophenol (4NP) into 4-aminophenol (4AP), followed by UV-visible spectroscopy. The kinetic advance of the reaction revealed important improvements in the catalytic activity of the materials by synergistic effect of BNPs and plasmonic enhancement under visible light irradiation, given the combination of metals and the light harvesting properties of the nanocomposites. Finally, the catalytic performance of hydrogels containing BNPs CuAu 3:1 showed an important selectivity, recyclability and reusability performance, due to the relevant interaction of the BNPs with the chitosan matrix, highlighting the potential of this nanocomposite as an effective catalyst, with a potential environmental application.
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Affiliation(s)
- Oscar Ramírez
- Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, 7820436, Chile.
| | - Sebastián Bonardd
- Materials Physics Center, CSIC-UPV/EHU, San Sebastián, 20018, Spain; Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, University of the Basque Country UPV/EHU, Donostia-San Sebastian, 20018, Spain
| | - César Saldías
- Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, 7820436, Chile
| | - Angel Leiva
- Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, 7820436, Chile.
| | - David Díaz Díaz
- Departamento de Química Orgánica, Avda. Astrofísico Francisco Sánchez 3, La Laguna 38206, Tenerife, Spain; Instituto Universitario de Bio-Orgánica Antonio González, Astrofísico Francisco Sánchez 2, La Laguna 38206, Tenerife, Spain.
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37
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Taxeidis G, Djapovic M, Nikolaivits E, Maslak V, Nikodinovic-Runic J, Topakas E. New Labeled PET Analogues Enable the Functional Screening and Characterization of PET-Degrading Enzymes. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2024; 12:5943-5952. [PMID: 38903150 PMCID: PMC11187625 DOI: 10.1021/acssuschemeng.4c00143] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 03/14/2024] [Accepted: 03/15/2024] [Indexed: 06/22/2024]
Abstract
The discovery and engineering of novel biocatalysts capable of depolymerizing polyethylene terephthalate (PET) have gained significant attention since the need for green technologies to combat plastic pollution has become increasingly urgent. This study focuses on the development of novel substrates that can indicate enzymes with PET hydrolytic activity, streamlining the process of enzyme evaluation and selection. Four novel substrates, mimicking the structure of PET, were chemically synthesized and labeled with fluorogenic or chromogenic moieties, enabling the direct analysis of candidate enzymes without complex preparatory or analysis steps. The fluorogenic substrates, mUPET1, mUPET2, and mUPET3, not only identify enzymes capable of PET breakdown but also differentiate those with exceptional performance on the polymer, such as the benchmark PETase, LCCICCG. Among the substrates, the chromogenic p-NPhPET3 stands out as a reliable tool for screening both pure and crude enzymes, offering advantages over fluorogenic substrates such as ease of assay using UV-vis spectroscopy and compatibility with crude enzyme samples. However, ferulic acid esterases and mono-(2-hydroxyethyl) terephthalate esterases (MHETases), which exhibit remarkably high affinity for PET oligomers, also show high catalytic activity on these substrates. The substrates introduced in this study hold significant value in the function-based screening and characterization of enzymes that degrade PET, as well as the the potential to be used in screening mutant libraries derived from directed evolution experiments. Following this approach, a rapid and dependable assay method can be carried out using basic laboratory infrastructure, eliminating the necessity for intricate preparatory procedures before analysis.
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Affiliation(s)
- George Taxeidis
- Industrial
Biotechnology & Biocatalysis Group, Biotechnology Laboratory,
School of Chemical Engineering, National
Technical University of Athens, Heroon Polytechniou 9, Zografou, 15772 Athens, Greece
| | - Milica Djapovic
- Faculty
of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Belgrade, Serbia
| | - Efstratios Nikolaivits
- Industrial
Biotechnology & Biocatalysis Group, Biotechnology Laboratory,
School of Chemical Engineering, National
Technical University of Athens, Heroon Polytechniou 9, Zografou, 15772 Athens, Greece
| | - Veselin Maslak
- Faculty
of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Belgrade, Serbia
| | - Jasmina Nikodinovic-Runic
- Institute
of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia
| | - Evangelos Topakas
- Industrial
Biotechnology & Biocatalysis Group, Biotechnology Laboratory,
School of Chemical Engineering, National
Technical University of Athens, Heroon Polytechniou 9, Zografou, 15772 Athens, Greece
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38
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Zheng L, Wang M, Li Y, Xiong Y, Wu C. Recycling and Degradation of Polyamides. Molecules 2024; 29:1742. [PMID: 38675560 PMCID: PMC11052090 DOI: 10.3390/molecules29081742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 03/31/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
As one of the five major engineering plastics, polyamide brings many benefits to humans in the fields of transportation, clothing, entertainment, health, and more. However, as the production of polyamide increases year by year, the pollution problems it causes are becoming increasingly severe. This article reviews the current recycling and treatment processes of polyamide, such as chemical, mechanical, and energy recovery, and degradation methods such as thermal oxidation, photooxidation, enzyme degradation, etc. Starting from the synthesis mechanism of polyamide, it discusses the advantages and disadvantages of different treatment methods of polyamide to obtain more environmentally friendly and economical treatment schemes. Finding enzymes that can degrade high-molecular-weight polyamides, exploring the recovery of polyamides under mild conditions, synthesizing environmentally degradable polyamides through copolymerization or molecular design, and finally preparing degradable bio-based polyamides may be the destination of polyamide.
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Affiliation(s)
- Lin Zheng
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-Weight Materials and Processing, New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base, School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China; (L.Z.); (M.W.); (Y.L.); (Y.X.)
| | - Mengjin Wang
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-Weight Materials and Processing, New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base, School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China; (L.Z.); (M.W.); (Y.L.); (Y.X.)
| | - Yaoqin Li
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-Weight Materials and Processing, New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base, School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China; (L.Z.); (M.W.); (Y.L.); (Y.X.)
| | - Yan Xiong
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-Weight Materials and Processing, New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base, School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China; (L.Z.); (M.W.); (Y.L.); (Y.X.)
- Hubei Longzhong Laboratory, Xiangyang 441000, China
| | - Chonggang Wu
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-Weight Materials and Processing, New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base, School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China; (L.Z.); (M.W.); (Y.L.); (Y.X.)
- Hubei Longzhong Laboratory, Xiangyang 441000, China
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39
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Shi C, Quinn EC, Diment WT, Chen EYX. Recyclable and (Bio)degradable Polyesters in a Circular Plastics Economy. Chem Rev 2024; 124:4393-4478. [PMID: 38518259 DOI: 10.1021/acs.chemrev.3c00848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2024]
Abstract
Polyesters carrying polar main-chain ester linkages exhibit distinct material properties for diverse applications and thus play an important role in today's plastics economy. It is anticipated that they will play an even greater role in tomorrow's circular plastics economy that focuses on sustainability, thanks to the abundant availability of their biosourced building blocks and the presence of the main-chain ester bonds that can be chemically or biologically cleaved on demand by multiple methods and thus bring about more desired end-of-life plastic waste management options. Because of this potential and promise, there have been intense research activities directed at addressing recycling, upcycling or biodegradation of existing legacy polyesters, designing their biorenewable alternatives, and redesigning future polyesters with intrinsic chemical recyclability and tailored performance that can rival today's commodity plastics that are either petroleum based and/or hard to recycle. This review captures these exciting recent developments and outlines future challenges and opportunities. Case studies on the legacy polyesters, poly(lactic acid), poly(3-hydroxyalkanoate)s, poly(ethylene terephthalate), poly(butylene succinate), and poly(butylene-adipate terephthalate), are presented, and emerging chemically recyclable polyesters are comprehensively reviewed.
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Affiliation(s)
- Changxia Shi
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Ethan C Quinn
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Wilfred T Diment
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Eugene Y-X Chen
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
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40
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Frey B, Aiesi M, Rast BM, Rüthi J, Julmi J, Stierli B, Qi W, Brunner I. Searching for new plastic-degrading enzymes from the plastisphere of alpine soils using a metagenomic mining approach. PLoS One 2024; 19:e0300503. [PMID: 38578779 PMCID: PMC10997104 DOI: 10.1371/journal.pone.0300503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 02/28/2024] [Indexed: 04/07/2024] Open
Abstract
Plastic materials, including microplastics, accumulate in all types of ecosystems, even in remote and cold environments such as the European Alps. This pollution poses a risk for the environment and humans and needs to be addressed. Using shotgun DNA metagenomics of soils collected in the eastern Swiss Alps at about 3,000 m a.s.l., we identified genes and their proteins that potentially can degrade plastics. We screened the metagenomes of the plastisphere and the bulk soil with a differential abundance analysis, conducted similarity-based screening with specific databases dedicated to putative plastic-degrading genes, and selected those genes with a high probability of signal peptides for extracellular export and a high confidence for functional domains. This procedure resulted in a final list of nine candidate genes. The lengths of the predicted proteins were between 425 and 845 amino acids, and the predicted genera producing these proteins belonged mainly to Caballeronia and Bradyrhizobium. We applied functional validation, using heterologous expression followed by enzymatic assays of the supernatant. Five of the nine proteins tested showed significantly increased activities when we used an esterase assay, and one of these five proteins from candidate genes, a hydrolase-type esterase, clearly had the highest activity, by more than double. We performed the fluorescence assays for plastic degradation of the plastic types BI-OPL and ecovio® only with proteins from the five candidate genes that were positively active in the esterase assay, but like the negative controls, these did not show any significantly increased activity. In contrast, the activity of the positive control, which contained a PLA-degrading gene insert known from the literature, was more than 20 times higher than that of the negative controls. These findings suggest that in silico screening followed by functional validation is suitable for finding new plastic-degrading enzymes. Although we only found one new esterase enzyme, our approach has the potential to be applied to any type of soil and to plastics in various ecosystems to search rapidly and efficiently for new plastic-degrading enzymes.
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Affiliation(s)
- Beat Frey
- Swiss Federal Institute for Forest, Forest Soils and Biogeochemistry, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Margherita Aiesi
- Swiss Federal Institute for Forest, Forest Soils and Biogeochemistry, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Facoltà de Science Agrarie e Alimentari, University Degli Studi di Milano, Milano, Italy
| | - Basil M. Rast
- Swiss Federal Institute for Forest, Forest Soils and Biogeochemistry, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Joel Rüthi
- Swiss Federal Institute for Forest, Forest Soils and Biogeochemistry, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Jérôme Julmi
- Swiss Federal Institute for Forest, Forest Soils and Biogeochemistry, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Beat Stierli
- Swiss Federal Institute for Forest, Forest Soils and Biogeochemistry, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Weihong Qi
- Functional Genomics Center Zürich, ETH Zürich and University of Zürich, Zürich, Switzerland
- Swiss Institute of Bioinformatics SIB, Geneva, Switzerland
| | - Ivano Brunner
- Swiss Federal Institute for Forest, Forest Soils and Biogeochemistry, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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41
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Makryniotis K, Nikolaivits E, Taxeidis G, Nikodinovic-Runic J, Topakas E. Exploring the substrate spectrum of phylogenetically distinct bacterial polyesterases. Biotechnol J 2024; 19:e2400053. [PMID: 38593303 DOI: 10.1002/biot.202400053] [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: 02/12/2024] [Revised: 03/09/2024] [Accepted: 03/25/2024] [Indexed: 04/11/2024]
Abstract
The rapid escalation of plastic waste accumulation presents a significant threat of the modern world, demanding an immediate solution. Over the last years, utilization of the enzymatic machinery of various microorganisms has emerged as an environmentally friendly asset in tackling this pressing global challenge. Thus, various hydrolases have been demonstrated to effectively degrade polyesters. Plastic waste streams often consist of a variety of different polyesters, as impurities, mainly due to wrong disposal practices, rendering recycling process challenging. The elucidation of the selective degradation of polyesters by hydrolases could offer a proper solution to this problem, enhancing the recyclability performance. Towards this, our study focused on the investigation of four bacterial polyesterases, including DaPUase, IsPETase, PfPHOase, and Se1JFR, a novel PETase-like lipase. The enzymes, which were biochemically characterized and structurally analyzed, demonstrated degradation ability of synthetic plastics. While a consistent pattern of polyesters' degradation was observed across all enzymes, Se1JFR stood out in the degradation of PBS, PLA, and polyether PU. Additionally, it exhibited comparable results to IsPETase, a benchmark mesophilic PETase, in the degradation of PCL and semi-crystalline PET. Our results point out the wide substrate spectrum of bacterial hydrolases and underscore the significant potential of PETase-like enzymes in polyesters degradation.
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Affiliation(s)
- Konstantinos Makryniotis
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - Efstratios Nikolaivits
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - George Taxeidis
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - Jasmina Nikodinovic-Runic
- Eco-Biotechnology & Drug Development Group, Laboratory for Microbial Molecular Genetics and Ecology, Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia
| | - Evangelos Topakas
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
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42
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Gopal MR, Kunjapur AM. Harnessing biocatalysis to achieve selective functional group interconversion of monomers. Curr Opin Biotechnol 2024; 86:103093. [PMID: 38417202 DOI: 10.1016/j.copbio.2024.103093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 03/01/2024]
Abstract
Polymeric materials are ubiquitous to modern life. However, reliance of petroleum for polymeric building blocks is not sustainable. The synthesis of macromolecules from recalcitrant polymer waste feedstocks, such as plastic waste and lignocellulosic biomass, presents an opportunity to bypass the use of petroleum-based feedstocks. However, the deconstruction and transformation of these alternative feedstocks remained limited until recently. Herein, we highlight examples of monomers liberated from the deconstruction of recalcitrant polymers, and more extensively, we showcase the state-of-the-art in biocatalytic technologies that are enabling synthesis of diverse upcycled monomeric starting materials for a wide variety of macromolecules. Overall, this review emphasizes the importance of functional group interconversion as a promising strategy by which biocatalysis can aid the diversification and upcycling of monomers.
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Affiliation(s)
- Madan R Gopal
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, USA; Center for Plastics Innovation, University of Delaware, Newark, DE, USA
| | - Aditya M Kunjapur
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, USA; Center for Plastics Innovation, University of Delaware, Newark, DE, USA.
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43
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Barbe V, Jacquin J, Bouzon M, Wolinski A, Derippe G, Cheng J, Cruaud C, Roche D, Fouteau S, Petit JL, Conan P, Pujo-Pay M, Bruzaud S, Ghiglione JF. Bioplastic degradation and assimilation processes by a novel bacterium isolated from the marine plastisphere. JOURNAL OF HAZARDOUS MATERIALS 2024; 466:133573. [PMID: 38306834 DOI: 10.1016/j.jhazmat.2024.133573] [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: 10/17/2023] [Revised: 11/23/2023] [Accepted: 01/17/2024] [Indexed: 02/04/2024]
Abstract
Biosourced and biodegradable plastics offer a promising solution to reduce environmental impacts of plastics for specific applications. Here, we report a novel bacterium named Alteromonas plasticoclasticus MED1 isolated from the marine plastisphere that forms biofilms on foils of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Experiments of degradation halo, plastic matrix weight loss, bacterial oxygen consumption and heterotrophic biosynthetic activity showed that the bacterial isolate MED1 is able to degrade PHBV and to use it as carbon and energy source. The likely entire metabolic pathway specifically expressed by this bacterium grown on PHBV matrices was shown by further genomic and transcriptomic analysis. In addition to a gene coding for a probable secreted depolymerase, a gene cluster was located that encodes characteristic enzymes involved in the complete depolymerization of PHBV, the transport of oligomers, and in the conversion of the monomers into intermediates of central carbon metabolism. The transcriptomic experiments showed the activation of the glyoxylate shunt during PHBV degradation, setting the isocitrate dehydrogenase activity as regulated branching point of the carbon flow entering the tricarboxylic acid cycle. Our study also shows the potential of exploring the natural plastisphere to discover new bacteria with promising metabolic capabilities.
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Affiliation(s)
- Valérie Barbe
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France
| | - Justine Jacquin
- CNRS, Sorbonne Université, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls, France
| | - Madeleine Bouzon
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France
| | - Adèle Wolinski
- CNRS, Sorbonne Université, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls, France
| | - Gabrielle Derippe
- CNRS, Sorbonne Université, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls, France; Institut de Recherche Dupuy de Lôme (IRDL), Université de Bretagne-Sud, UMR CNRS 6027, Rue Saint Maudé, Lorient, France
| | - Jingguang Cheng
- CNRS, Sorbonne Université, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls, France
| | - Corinne Cruaud
- Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France
| | - David Roche
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France
| | - Stéphanie Fouteau
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France
| | - Jean-Louis Petit
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France
| | - Pascal Conan
- CNRS, Sorbonne Université, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls, France
| | - Mireille Pujo-Pay
- CNRS, Sorbonne Université, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls, France
| | - Stéphane Bruzaud
- Institut de Recherche Dupuy de Lôme (IRDL), Université de Bretagne-Sud, UMR CNRS 6027, Rue Saint Maudé, Lorient, France
| | - Jean-François Ghiglione
- CNRS, Sorbonne Université, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique de Banyuls, France.
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He L, Yang SS, Ding J, Chen CX, Yang F, He ZL, Pang JW, Peng BY, Zhang Y, Xing DF, Ren NQ, Wu WM. Biodegradation of polyethylene terephthalate by Tenebrio molitor: Insights for polymer chain size, gut metabolome and host genes. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133446. [PMID: 38219578 DOI: 10.1016/j.jhazmat.2024.133446] [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: 08/18/2023] [Revised: 01/02/2024] [Accepted: 01/03/2024] [Indexed: 01/16/2024]
Abstract
Polyethylene terephthalate (PET or polyester) is a commonly used plastic and also contributes to the majority of plastic wastes. Mealworms (Tenebrio molitor larvae) are capable of biodegrading major plastic polymers but their degrading ability for PET has not been characterized based on polymer chain size molecular size, gut microbiome, metabolome and transcriptome. We verified biodegradation of commercial PET by T. molitor larvae in a previous report. Here, we reported that biodegradation of commercial PET (Mw 29.43 kDa) was further confirmed by using the δ13C signature as an indication of bioreaction, which was increased from - 27.50‰ to - 26.05‰. Under antibiotic suppression of gut microbes, the PET was still depolymerized, indicating that the host digestive enzymes could degrade PET independently. Biodegradation of high purity PET with low, medium, and high molecular weights (MW), i.e., Mw values of 1.10, 27.10, and 63.50 kDa with crystallinity 53.66%, 33.43%, and 4.25%, respectively, showed a mass reduction of > 95%, 86%, and 74% via broad depolymerization. Microbiome analyses indicated that PET diets shifted gut microbiota to three distinct structures, depending on the low, medium, and high MW. Metagenome sequencing, transcriptomic, and metabolic analyses indicated symbiotic biodegradation of PET by the host and gut microbiota. After PET was fed, the host's genes encoding degradation enzymes were upregulated, including genes encoding oxidizing, hydrolyzing, and non-specific CYP450 enzymes. Gut bacterial genes for biodegrading intermediates and nitrogen fixation also upregulated. The multiple-functional metabolic pathways for PET biodegradation ensured rapid biodegradation resulting in a half-life of PET less than 4 h with less negative impact by PET MW and crystallinity.
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Affiliation(s)
- Lei He
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Shan-Shan Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Jie Ding
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Cheng-Xin Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Fan Yang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150090, China
| | - Zhi-Li He
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China
| | - Ji-Wei Pang
- China Energy Conservation and Environmental Protection Group, Beijing 100089, China
| | - Bo-Yu Peng
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yalei Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - De-Feng Xing
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Nan-Qi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wei-Min Wu
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Stanford University, Stanford, CA 94305, USA.
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45
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Zhou X, Zhou X, Xu Z, Zhang M, Zhu H. Characterization and engineering of plastic-degrading polyesterases jmPE13 and jmPE14 from Pseudomonas bacterium. Front Bioeng Biotechnol 2024; 12:1349010. [PMID: 38425995 PMCID: PMC10904013 DOI: 10.3389/fbioe.2024.1349010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 01/31/2024] [Indexed: 03/02/2024] Open
Abstract
Polyester plastics are widely used in daily life, but also cause a large amount of waste. Degradation by microbial enzymes is the most promising way for the biobased upcycling of the wastes. However, there is still a shortage of high-performance enzymes, and more efficient polyester hydrolases need to be developed. Here we identified two polyester hydrolases, jmPE13 and jmPE14, from a previously isolated strain Pseudomonas sp. JM16B3. The proteins were recombinantly expressed and purified in E. coli, and their enzymatic properties were characterized. JmPE13 and jmPE14 showed hydrolytic activity towards polyethylene terephthalate (PET) and Poly (butylene adipate-co-terephthalate) (PBAT) at medium temperatures. The enzyme activity and stability of jmPE13 were further improved to 3- and 1.5-fold, respectively, by rational design. The results of our research can be helpful for further engineering of more efficient polyester plastic hydrolases and their industrial applications.
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Affiliation(s)
| | | | | | | | - Honghui Zhu
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Key Laboratory of Agricultural Microbiome (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
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46
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Bell EL, Rosetto G, Ingraham MA, Ramirez KJ, Lincoln C, Clarke RW, Gado JE, Lilly JL, Kucharzyk KH, Erickson E, Beckham GT. Natural diversity screening, assay development, and characterization of nylon-6 enzymatic depolymerization. Nat Commun 2024; 15:1217. [PMID: 38336849 PMCID: PMC10858056 DOI: 10.1038/s41467-024-45523-5] [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: 09/10/2023] [Accepted: 01/24/2024] [Indexed: 02/12/2024] Open
Abstract
Successes in biocatalytic polyester recycling have raised the possibility of deconstructing alternative polymers enzymatically, with polyamide (PA) being a logical target due to the array of amide-cleaving enzymes present in nature. Here, we screen 40 potential natural and engineered nylon-hydrolyzing enzymes (nylonases), using mass spectrometry to quantify eight compounds resulting from enzymatic nylon-6 (PA6) hydrolysis. Comparative time-course reactions incubated at 40-70 °C showcase enzyme-dependent variations in product distributions and extent of PA6 film depolymerization, with significant nylon deconstruction activity appearing rare. The most active nylonase, a NylCK variant we rationally thermostabilized (an N-terminal nucleophile (Ntn) hydrolase, NylCK-TS, Tm = 87.4 °C, 16.4 °C higher than the wild-type), hydrolyzes 0.67 wt% of a PA6 film. Reactions fail to restart after fresh enzyme addition, indicating that substrate-based limitations, such as restricted enzyme access to hydrolysable bonds, prohibit more extensive deconstruction. Overall, this study expands our understanding of nylonase activity distribution, indicates that Ntn hydrolases may have the greatest potential for further development, and identifies key targets for progressing PA6 enzymatic depolymerization, including improving enzyme activity, product selectivity, and enhancing polymer accessibility.
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Affiliation(s)
- Elizabeth L Bell
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- BOTTLE Consortium, Golden, CO, 80401, USA
| | - Gloria Rosetto
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Morgan A Ingraham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- BOTTLE Consortium, Golden, CO, 80401, USA
| | - Kelsey J Ramirez
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- BOTTLE Consortium, Golden, CO, 80401, USA
| | - Clarissa Lincoln
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- BOTTLE Consortium, Golden, CO, 80401, USA
| | - Ryan W Clarke
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- BOTTLE Consortium, Golden, CO, 80401, USA
| | - Japheth E Gado
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- BOTTLE Consortium, Golden, CO, 80401, USA
| | - Jacob L Lilly
- Battelle Memorial Institute, Columbus, OH, 43201, USA
| | | | - Erika Erickson
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- BOTTLE Consortium, Golden, CO, 80401, USA
| | - Gregg T Beckham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA.
- BOTTLE Consortium, Golden, CO, 80401, USA.
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47
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Amalia L, Chang CY, Wang SSS, Yeh YC, Tsai SL. Recent advances in the biological depolymerization and upcycling of polyethylene terephthalate. Curr Opin Biotechnol 2024; 85:103053. [PMID: 38128200 DOI: 10.1016/j.copbio.2023.103053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 11/16/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023]
Abstract
Polyethylene terephthalate (PET) is favored for its exceptional properties and widespread daily use. This review highlights recent advancements that enable the development of biological tools for PET decomposition, transforming PET into valuable platform chemicals and materials in upcycling processes. Enhancing PET hydrolases' catalytic activity and efficiency through protein engineering strategies is a priority, facilitating more effective PET waste management. Efforts to create novel PET hydrolases for large-scale PET depolymerization continue, but cost-effectiveness remains challenging. Hydrolyzed monomers must add additional value to make PET recycling economically attractive. Valorization of hydrolysis products through the upcycling process is expected to produce new compounds with different values and qualities from the initial polymer, making the decomposed monomers more appealing. Advances in synthetic biology and enzyme engineering hold promise for PET upcycling. While biological depolymerization offers environmental benefits, further research is needed to make PET upcycling sustainable and economically feasible.
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Affiliation(s)
- Lita Amalia
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan
| | - Chia-Yu Chang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Steven S-S Wang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Yi-Chun Yeh
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Shen-Long Tsai
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan.
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48
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Thomsen TB, Radmer TS, Meyer AS. Enzymatic degradation of poly(ethylene terephthalate) (PET): Identifying the cause of the hypersensitive enzyme kinetic response to increased PET crystallinity. Enzyme Microb Technol 2024; 173:110353. [PMID: 37979402 DOI: 10.1016/j.enzmictec.2023.110353] [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: 10/04/2023] [Revised: 11/01/2023] [Accepted: 11/01/2023] [Indexed: 11/20/2023]
Abstract
Plastic pollution poses a significant environmental challenge, with poly(ethylene terephthalate) (PET) being a major contributor due to its extensive use in single use applications such as plastic bottles and other packaging material. Enzymatic degradation of PET offers a promising solution for PET recycling, but the enzyme kinetics in relation to the degree of crystallinity (XC) of the PET substrate are poorly understood. In this study, we investigated the hypersensitive enzyme kinetic response on PET at XC from ∼8.5-12% at 50 °C using the benchmark PET hydrolysing enzyme LCCICCG. We observed a substantial reduction in the maximal enzymatic reaction rate (invVmax) with increasing XC, corresponding to a 3-fold reduction in invVmax when the XC of PET increased from 8.6% to 12.2%. The kinetic analysis revealed that the level of the Mobile Amorphous Fraction (XMAF) was a better descriptor for the enzymatic degradation rate response than XC (or (100%-XC)). By continuous monitoring of the enzymatic reaction progress, we quantified the lag phase prolongation in addition to the steady-state kinetic rates (vss) of the reactions and found that the duration of the lag phase of a reaction could be predicted from the vss and XC by multiple linear regression modeling. The linear correlation between the duration of the lag phase and the vss of the enzymatic PET degradation affirmed that the LCCICCG worked via a random/endo-type enzymatic attack pattern. The longer lag phase at increased XC of PET is proposed to be due to increased substrate entanglement density as well as unproductive enzyme binding to the crystalline regions of PET. The findings enhance our understanding of PET enzymatic degradation kinetics and its dependence on substrate composition, i.e., XMAF and XC.
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Affiliation(s)
- Thore Bach Thomsen
- Protein Chemistry and Enzyme Technology Section, Department of Biotechnology and Biomedicine, DTU Bioengineering, Technical University of Denmark, Building 221, 2800 Kgs. Lyngby, Denmark
| | - Tobias S Radmer
- Protein Chemistry and Enzyme Technology Section, Department of Biotechnology and Biomedicine, DTU Bioengineering, Technical University of Denmark, Building 221, 2800 Kgs. Lyngby, Denmark
| | - Anne S Meyer
- Protein Chemistry and Enzyme Technology Section, Department of Biotechnology and Biomedicine, DTU Bioengineering, Technical University of Denmark, Building 221, 2800 Kgs. Lyngby, Denmark.
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49
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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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50
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Oda K, Wlodawer A. Development of Enzyme-Based Approaches for Recycling PET on an Industrial Scale. Biochemistry 2024. [PMID: 38285602 DOI: 10.1021/acs.biochem.3c00554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2024]
Abstract
Pollution by plastics such as polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyurethane (PUR), polyamide (PA), polystyrene (PS), and poly(ethylene terephthalate) (PET) is now gaining worldwide attention as a critical environmental issue, closely linked to climate change. Among them, PET is particularly prone to hydrolysis, breaking down into its constituents, ethylene glycol (EG) and terephthalate (TPA). Biorecycling or bioupcycling stands out as one of the most promising methods for addressing PET pollution. For dealing with pollution by the macrosize PET, a French company Carbios has developed a pilot-scale plant for biorecycling waste PET beverage bottles into new bottles using derivatives of thermophilic leaf compost cutinase (LCC). However, this system still provides significant challenges in its practical implementation. For the micro- or nanosize PET pollution that poses significant human health risks, including cancer, no industrial-scale approach has been established so far, despite the need to develop such technologies. In this Perspective, we explore the enhancement of the low activity and thermostability of the enzyme PETase to match that of LCC, along with the potential application of microbes and enzymes for the treatment of waste PET as microplastics. Additionally, we discuss the shortcomings of the current biorecycling protocols from a life cycle assessment perspective, covering aspects such as the diversity of PET-hydrolyzing enzymes in nature, the catalytic mechanism for crystallized PET, and more. We also provide an overview of the Ideonella sakaiensis system, highlighting its ability to operate and grow at moderate temperatures, in contrast to high-temperature processes.
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Affiliation(s)
- Kohei Oda
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Alexander Wlodawer
- Center for Structural Biology, National Cancer Institute, Frederick, Maryland 21702, United States
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