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Feng Y, Duan J, Yang C, Zou Q, Chen Z, Pu J, Xiang Y, Chen M, Fan M, Zhang H. Microplastics and benthic animals reshape the geochemical characteristics of dissolved organic matter by inducing changes in keystone microbes in riparian sediments. ENVIRONMENTAL RESEARCH 2024; 262:119806. [PMID: 39151559 DOI: 10.1016/j.envres.2024.119806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 08/10/2024] [Accepted: 08/14/2024] [Indexed: 08/19/2024]
Abstract
Dissolved organic matter (DOM) in riparian sediments plays a vital role in regulating element cycling and pollutant behavior of river ecosystems. Microplastics (MPs) and benthic animals (BAs) have been frequently detected in riparian sediments, influencing the substance transformation in river ecosystems. However, there is still a lack of systematic investigation on the effects of MPs and BAs on sediment DOM. This study investigated the impact of MPs and BAs on the geochemical characteristics of DOM in riparian sediments and their microbial mechanisms. The results showed that MPs and BAs increased sediment DOC concentration by 34.24%∼232.97% and promoted the conversion of macromolecular components to small molecular components, thereby reducing the humification degree of DOM. Mathematical model verified that the changes of keystone microbes composition in sediments were direct factors affecting the characteristics of DOM in riparian sediment. Especially, MPs tolerant microbes, including Planctomicrobium, Rhodobacter, Hirschia and Lautropia, significantly increased DOC concentration and decreased humification degree (P < 0.05). In addition, MPs and BAs could also influence keystone microbes in sediments by altering the structure of microbial network, thereby indirectly affecting DOM characteristics. The study demonstrates the pollution behavior of MPs in river ecosystems and provides a basis for protecting the ecological function of riparian sediments from MPs pollution.
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Affiliation(s)
- Yuanyuan Feng
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China
| | - Jinjiang Duan
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China
| | - Cheng Yang
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China
| | - Qingping Zou
- School of Energy, Geoscience, Infrastructure and Society, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom
| | - Ziwei Chen
- Key Laboratory of Hydraulic and Waterway Engineering, Ministry of Education, Chongqing Jiaotong University, Chongqing, 400074, China
| | - Jia Pu
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China
| | - Yu Xiang
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China
| | - Mengli Chen
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China.
| | - Meikun Fan
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China
| | - Han Zhang
- School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, 611756, China.
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2
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Fernandes M, Salvador AF, Vicente AA. Biodegradation of PHB/PBAT films and isolation of novel PBAT biodegraders from soil microbiomes. CHEMOSPHERE 2024; 362:142696. [PMID: 38925517 DOI: 10.1016/j.chemosphere.2024.142696] [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: 09/29/2023] [Revised: 06/04/2024] [Accepted: 06/23/2024] [Indexed: 06/28/2024]
Abstract
Polyhydroxyalkanoates (PHAs) are important candidates for replacing petroleum-based plastics. This transition is urgent for the development of a biobased economy and to protect human health and natural ecosystems. PHAs are biobased and biodegradable polyesters that when blended with other polymers, such as poly(butylene adipate-co-terephthalate) (PBAT), acquire remarkable improvements in their properties, which allow them to comply with the requirements of packaging applications. However, the biodegradation of such blends should be tested to evaluate the impact of those polymers in the environment. For instance, PBAT is a compostable aliphatic-aromatic copolyester, and its biodegradation in natural environments, such as soil, is poorly studied. In this work, we evaluated the biodegradation of a bilayer film composed of PHB and PBAT, by a soil microbiome. The bilayer film reached 47 ± 1 % mineralization in 180 days and PHB was no longer detected after this period. The increased crystallinity of the PBAT residue was a clear sign of biodegradation, indicating that the amorphous regions were preferentially biodegraded. Seven microorganisms were isolated, from which 4 were closely related to microorganisms already known as PHB degraders, but the other 3 species, closely related to Streptomyces coelicoflavus, Clonostachys rosea and Aspergillus insuetus, were found for the first time as PHB degraders. Most remarkably, two fungi closely related to Purpureocillium lilacinum and Aspergillus pseudodeflectus (99.83 % and 100 % identity by ITS sequencing) were isolated and identified as PBAT degraders. This is very interesting due to the rarity of isolating PBAT-degrading microorganisms. These results show that the bilayer film can be biodegraded in soil, at mesophilic temperatures, showing its potential to replace synthetic plastics in food packaging.
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Affiliation(s)
- Miguel Fernandes
- Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; LABBELS - Associate Laboratory, Braga/Guimarães, Portugal.
| | - Andreia F Salvador
- Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; LABBELS - Associate Laboratory, Braga/Guimarães, Portugal.
| | - António A Vicente
- Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; LABBELS - Associate Laboratory, Braga/Guimarães, Portugal.
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3
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Pham VHT, Kim J, Chang S. A Valuable Source of Promising Extremophiles in Microbial Plastic Degradation. Polymers (Basel) 2024; 16:2109. [PMID: 39125136 PMCID: PMC11314448 DOI: 10.3390/polym16152109] [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: 05/23/2024] [Revised: 07/01/2024] [Accepted: 07/22/2024] [Indexed: 08/12/2024] Open
Abstract
Plastics have accumulated in open environments, such as oceans, rivers, and land, for centuries, but their effect has been of concern for only decades. Plastic pollution is a global challenge at the forefront of public awareness worldwide due to its negative effects on ecological systems, animals, human health, and national economies. Therefore, interest has increased regarding specific circular economies for the development of plastic production and the investigation of green technologies for plastic degradation after use on an appropriate timescale. Moreover, biodegradable plastics have been found to contain potential new hazards compared with conventional plastics due to the physicochemical properties of the polymers involved. Recently, plastic biodegradation was defined as microbial conversion using functional microorganisms and their enzymatic systems. This is a promising strategy for depolymerizing organic components into carbon dioxide, methane, water, new biomass, and other higher value bioproducts under both oxic and anoxic conditions. This study reviews microplastic pollution, the negative consequences of plastic use, and the current technologies used for plastic degradation and biodegradation mediated by microorganisms with their drawbacks; in particular, the important and questionable role of extremophilic multi-enzyme-producing bacteria in synergistic systems of plastic decomposition is discussed. This study emphasizes the key points for enhancing the plastic degradation process using extremophiles, such as cell hydrophobicity, amyloid protein, and other relevant factors. Bioprospecting for novel mechanisms with unknown information about the bioproducts produced during the plastic degradation process is also mentioned in this review with the significant goals of CO2 evolution and increasing H2/CH4 production in the future. Based on the potential factors that were analyzed, there may be new ideas for in vitro isolation techniques for unculturable/multiple-enzyme-producing bacteria and extremophiles from various polluted environments.
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Affiliation(s)
- Van Hong Thi Pham
- Department of Environmental Energy Engineering, College of Creative Engineering, Kyonggi University, Suwon 16227, Republic of Korea;
- Department of Life Science, College of Natural Science, Kyonggi University, Suwon 16227, Republic of Korea
| | - Jaisoo Kim
- Department of Life Science, College of Natural Science, Kyonggi University, Suwon 16227, Republic of Korea
| | - Soonwoong Chang
- Department of Environmental Energy Engineering, College of Creative Engineering, Kyonggi University, Suwon 16227, Republic of Korea;
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4
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Wang T, Yang WT, Gong YM, Zhang YK, Fan XX, Wang GC, Lu ZH, Liu F, Liu XH, Zhu YS. Molecular engineering of PETase for efficient PET biodegradation. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 280:116540. [PMID: 38833982 DOI: 10.1016/j.ecoenv.2024.116540] [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: 02/23/2024] [Revised: 05/29/2024] [Accepted: 05/31/2024] [Indexed: 06/06/2024]
Abstract
The widespread utilization of polyethylene terephthalate (PET) has caused a variety of environmental and health problems. Compared with traditional thermomechanical or chemical PET cycling, the biodegradation of PET may offer a more feasible solution. Though the PETase from Ideonalla sakaiensis (IsPETase) displays interesting PET degrading performance under mild conditions; the relatively low thermal stability of IsPETase limits its practical application. In this study, enzyme-catalysed PET degradation was investigated with the promising IsPETase mutant HotPETase (HP). On this basis, a carbohydrate-binding module from Bacillus anthracis (BaCBM) was fused to the C-terminus of HP to construct the PETase mutant (HLCB) for increased PET degradation. Furthermore, to effectively improve PET accessibility and PET-degrading activity, the truncated outer membrane hybrid protein (FadL) was used to expose PETase and BaCBM on the surface of E. coli (BL21with) to develop regenerable whole-cell biocatalysts (D-HLCB). Results showed that, among the tested small-molecular weight ester compounds (p-nitrophenyl phosphate (pNPP), p-Nitrophenyl acetate (pNPA), 4-Nitrophenyl butyrate (pNPB)), PETase displayed the highest hydrolysing activity against pNPP. HP displayed the highest catalytic activity (1.94 μM(p-NP)/min) at 50 °C and increased longevity at 40 °C. The fused BaCBM could clearly improve the catalytic performance of PETase by increasing the optimal reaction temperature and improving the thermostability. When HLCB was used for PET degradation, the yield of monomeric products (255.7 μM) was ∼25.5 % greater than that obtained after 50 h of HP-catalysed PET degradation. Moreover, the highest yield of monomeric products from the D-HLCB-mediated system reached 1.03 mM. The whole-cell catalyst D-HLCB displayed good reusability and stability and could maintain more than 54.6 % of its initial activity for nine cycles. Finally, molecular docking simulations were utilized to investigate the binding mechanism and the reaction mechanism of HLCB, which may provide theoretical evidence to further increase the PET-degrading activities of PETases through rational design. The proposed strategy and developed variants show potential for achieving complete biodegradation of PET under mild conditions.
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Affiliation(s)
- Tao Wang
- School of Biological Science, Jining Medical University, Jining, China
| | - Wen-Tao Yang
- School of Biological Science, Jining Medical University, Jining, China
| | - Yu-Ming Gong
- School of Biological Science, Jining Medical University, Jining, China
| | - Ying-Kang Zhang
- School of Biological Science, Jining Medical University, Jining, China
| | - Xin-Xin Fan
- School of Biological Science, Jining Medical University, Jining, China
| | - Guo-Cheng Wang
- School of Biological Science, Jining Medical University, Jining, China
| | - Zhen-Hua Lu
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Fei Liu
- School of Biological Science, Jining Medical University, Jining, China
| | - Xiao-Huan Liu
- School of Biological Science, Jining Medical University, Jining, China
| | - You-Shuang Zhu
- School of Biological Science, Jining Medical University, Jining, China.
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5
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Aarsen C, Liguori A, Mattsson R, Sipponen MH, Hakkarainen M. Designed to Degrade: Tailoring Polyesters for Circularity. Chem Rev 2024; 124:8473-8515. [PMID: 38936815 PMCID: PMC11240263 DOI: 10.1021/acs.chemrev.4c00032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 04/30/2024] [Accepted: 06/11/2024] [Indexed: 06/29/2024]
Abstract
A powerful toolbox is needed to turn the linear plastic economy into circular. Development of materials designed for mechanical recycling, chemical recycling, and/or biodegradation in targeted end-of-life environment are all necessary puzzle pieces in this process. Polyesters, with reversible ester bonds, are already forerunners in plastic circularity: poly(ethylene terephthalate) (PET) is the most recycled plastic material suitable for mechanical and chemical recycling, while common aliphatic polyesters are biodegradable under favorable conditions, such as industrial compost. However, this circular design needs to be further tailored for different end-of-life options to enable chemical recycling under greener conditions and/or rapid enough biodegradation even under less favorable environmental conditions. Here, we discuss molecular design of the polyester chain targeting enhancement of circularity by incorporation of more easily hydrolyzable ester bonds, additional dynamic bonds, or degradation catalyzing functional groups as part of the polyester chain. The utilization of polyester circularity to design replacement materials for current volume plastics is also reviewed as well as embedment of green catalysts, such as enzymes in biodegradable polyester matrices to facilitate the degradation process.
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Affiliation(s)
- Celine
V. Aarsen
- Department
of Fibre and Polymer Technology, KTH Royal
Institute of Technology, Teknikringen 58, 100 44 Stockholm, Sweden
| | - Anna Liguori
- Department
of Fibre and Polymer Technology, KTH Royal
Institute of Technology, Teknikringen 58, 100 44 Stockholm, Sweden
- Department
of Chemistry “G. Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Rebecca Mattsson
- Department
of Fibre and Polymer Technology, KTH Royal
Institute of Technology, Teknikringen 58, 100 44 Stockholm, Sweden
| | - Mika H. Sipponen
- Department
of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16C, 106
91 Stockholm, Sweden
| | - Minna Hakkarainen
- Department
of Fibre and Polymer Technology, KTH Royal
Institute of Technology, Teknikringen 58, 100 44 Stockholm, Sweden
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6
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Wang Y, van Putten RJ, Tietema A, Parsons JR, Gruter GJM. Polyester biodegradability: importance and potential for optimisation. GREEN CHEMISTRY : AN INTERNATIONAL JOURNAL AND GREEN CHEMISTRY RESOURCE : GC 2024; 26:3698-3716. [PMID: 38571729 PMCID: PMC10986773 DOI: 10.1039/d3gc04489k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Accepted: 01/23/2024] [Indexed: 04/05/2024]
Abstract
To reduce global CO2 emissions in line with EU targets, it is essential that we replace fossil-derived plastics with renewable alternatives. This provides an opportunity to develop novel plastics with improved design features, such as better reusability, recyclability, and environmental biodegradability. Although recycling and reuse of plastics is favoured, this relies heavily on the infrastructure of waste management, which is not consistently advanced on a worldwide scale. Furthermore, today's bulk polyolefin plastics are inherently unsuitable for closed-loop recycling, but the introduction of plastics with enhanced biodegradability could help to combat issues with plastic accumulation, especially for packaging applications. It is also important to recognise that plastics enter the environment through littering, even where the best waste-collection infrastructure is in place. This causes endless environmental accumulation when the plastics are non-(bio)degradable. Biodegradability depends heavily on circumstances; some biodegradable polymers degrade rapidly under tropical conditions in soil, but they may not also degrade at the bottom of the sea. Biodegradable polyesters are theoretically recyclable, and even if mechanical recycling is difficult, they can be broken down to their monomers by hydrolysis for subsequent purification and re-polymerisation. Additionally, both the physical properties and the biodegradability of polyesters are tuneable by varying their building blocks. The relationship between the (chemical) structures/compositions (aromatic, branched, linear, polar/apolar monomers; monomer chain length) and biodegradation/hydrolysis of polyesters is discussed here in the context of the design of biodegradable polyesters.
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Affiliation(s)
- Yue Wang
- van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | | | - Albert Tietema
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - John R Parsons
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - Gert-Jan M Gruter
- van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
- Avantium Support BV Zekeringstraat 29 1014 BV Amsterdam The Netherlands
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7
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Eck M, Mecking S. Closed-Loop Recyclable and Nonpersistent Polyethylene-like Polyesters. Acc Chem Res 2024; 57:971-980. [PMID: 38446139 PMCID: PMC10956388 DOI: 10.1021/acs.accounts.3c00811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/19/2024] [Accepted: 02/21/2024] [Indexed: 03/07/2024]
Abstract
ConspectusAliphatic polyesters based on long-chain monomers were synthesized for the first time almost a century ago. In fact, Carothers' seminal observations that founded the entire field of synthetic polymer fibers were made on such a polyester sample. However, as materials, they have evolved only over the past decade. This is driven by the corresponding monomers becoming practically available from advanced catalytic conversions of plant oils, and future prospects comprise a possible generation from third-generation feedstocks, such as microalgae or waste. Long-chain polyesters such as polyester-18.18 can be considered to be polyethylene chains with a low density of potential breakpoints in the chain. These do not compromise the crystalline structure or the material properties, which resemble linear high-density polyethylene (HDPE), and the materials can also be melt processed by injection molding, film or fiber extrusion, and filament deposition in additive manufacturing. At the same time, they enable closed-loop chemical recycling via solvolysis, which is also possible in mixed waste streams containing polyolefins and even poly(ethylene terephthalate). Recovered monomers possess a quality that enables the generation of recycled polyesters with properties on par with those of the virgin material. The (bio)degradability varies enormously with the constituent monomers. Polyesters based on short-chain diols and long-chain dicarboxylates fully mineralize under industrial composting conditions, despite their HDPE-like crystallinity and hydrophobicity. Fundamental studies of the morphology and thermal behavior of these polymers revealed the location of the in-chain groups and their peculiar role in structure formation during crystallization as well as during melting. All of the concepts outlined were extended to, and elaborated on further, by analogous long-chain aliphatic polymers with other in-chain groups such as carbonates and acetals. The title materials are a potential solution for much needed circular closed-loop recyclable plastics that also as a backstop if lost to the environment will not be persistent for many decades.
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Affiliation(s)
- Marcel Eck
- Chair of Chemical Materials
Science, Department of Chemistry, University
of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Stefan Mecking
- Chair of Chemical Materials
Science, Department of Chemistry, University
of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
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8
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Schwab S, Baur M, Nelson TF, Mecking S. Synthesis and Deconstruction of Polyethylene-type Materials. Chem Rev 2024; 124:2327-2351. [PMID: 38408312 PMCID: PMC10941192 DOI: 10.1021/acs.chemrev.3c00587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 01/16/2024] [Accepted: 02/07/2024] [Indexed: 02/28/2024]
Abstract
Polyethylene deconstruction to reusable smaller molecules is hindered by the chemical inertness of its hydrocarbon chains. Pyrolysis and related approaches commonly require high temperatures, are energy-intensive, and yield mixtures of multiple classes of compounds. Selective cleavage reactions under mild conditions (
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Affiliation(s)
- Simon
T. Schwab
- Chair of Chemical Materials Science,
Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
| | - Maximilian Baur
- Chair of Chemical Materials Science,
Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
| | - Taylor F. Nelson
- Chair of Chemical Materials Science,
Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
| | - Stefan Mecking
- Chair of Chemical Materials Science,
Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
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9
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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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10
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Chen M, Cao M, Zhang W, Chen X, Liu H, Ning Z, Peng L, Fan C, Wu D, Zhang M, Li Q. Effect of biodegradable PBAT microplastics on the C and N accumulation of functional organic pools in tropical latosol. ENVIRONMENT INTERNATIONAL 2024; 183:108393. [PMID: 38118212 DOI: 10.1016/j.envint.2023.108393] [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: 09/03/2023] [Revised: 11/17/2023] [Accepted: 12/15/2023] [Indexed: 12/22/2023]
Abstract
Microplastics (MPs) pollution is becoming an emerging global stressor for soil ecosystems. However, studies on the impacts of biodegradable MPs on soil C sequestration have been mainly based on bulk C quantity, without considering the storage form of C, its persistency and N demand. To address this issue, the common poly (butylene adipate-co-terephthalate) (PBAT) was used as the model, and its effects on soil functional organic pools, including mineral-associated (MAOM), particulate (POM) and dissolved organic matter (DOM), were investigated from the novel coupled perspective of C and N stocks. After adding PBAT-MPs, the contents of soil POM-C, DOM-C, and MAOM-C were increased by 546.9 %-697.8 %, 54.2 %-90.3 %, and 13.7 %-18.9 %, respectively. Accordingly, the total C increased by 116.0 %-191.1 %. Structural equation modeling showed that soil C pools were regulated by PBAT input and microbial metabolism associated with C and N enzymes. Specifically, PBAT debris could be disguised as soil C to promote POM formation, which was the main pathway for C accumulation. Inversely, the MAOM-C and DOM-C formation was attributed to the PBAT microbial product and the selective consumption in DOM-N. Random forest model confirmed that N-activated (e.g., Nitrospirae) and PBAT-degrading bacteria (e.g., Gemmatinadetes) were important taxa for soil C accumulation, and the key enzymes were rhizopus oryzae lipas, invertase, and ammonia monooxygenase. The soil N accumulation was mainly related to the oligotrophic taxa (e.g., Chloroflexi and Ascomycota) associated with aggregate formation, decreasing the DOM-N by 46.9 %-84.3 %, but did not significantly change the total N storage and other N pools. Collectively, the findings highlight the urgency to control the nutrient imbalance risk of labile N loss and recalcitrant C enrichment in POM to avoid the depressed turnover rate of organic matter in MPs-polluted soil.
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Affiliation(s)
- Miao Chen
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Ming Cao
- Agro-Tech Extension and Service Center of Sanya, Sanya 572000, Hainan, China
| | - Wen Zhang
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Xin Chen
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Huiran Liu
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Ziyu Ning
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Licheng Peng
- School of Ecology and Environment, Hainan University, Haikou 570228, China
| | - Changhua Fan
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Dongming Wu
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China.
| | - Meng Zhang
- School of Electronic and Information Engineering, Beihang University, Beijing 100191, China
| | - Qinfen Li
- Key Laboratory of Low-carbon Green Agriculture in Tropical Region of China, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory of Tropical Eco-Circuling Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
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11
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Pang W, Li B, Wu Y, Tian S, Zhang Y, Yang J. Optimization of degradation behavior and conditions for the protease K of polylactic acid films by simulation. Int J Biol Macromol 2023; 253:127496. [PMID: 37858641 DOI: 10.1016/j.ijbiomac.2023.127496] [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: 08/24/2023] [Revised: 10/09/2023] [Accepted: 10/15/2023] [Indexed: 10/21/2023]
Abstract
With global enforcement of plastic bans and restrictions, the biodegradable plastic, e.g., polylactic acid (PLA), has been extensively employed as a primary substitute for traditional petroleum-based plastics. However, the growing problem associated with PLA waste accumulation is posing grand environmental challenges. In addition, although PLA has the degrading property under natural conditions, the degradation process takes too long and the degradation products cannot be recycled. In this context, enzymatic degradation of PLA arouses great attention in scientific communities. This study aims at selecting the most cost-effective protease from various enzymes and optimizing the enzymolysis conditions towards the degradation of PLA. We will demonstrate that under an optimal temperature of 45 °C, a pH vale of 11, and an enzyme concentration of 0.6 mg mL-1, the protease K would achieve a remarkable degradation efficiency (> 99 %) for PLA films within just 50 min. Finally, molecular dynamics (MD) simulation and molecular docking studies reveal the mechanism behind the protease-induced PLA degradation, providing a promising direction for waste treatment and resource utilization for future biodegradable plastics.
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Affiliation(s)
- Wenlong Pang
- Institute of Circular Economy, Beijing University of Technology, Beijing, 100022, China; Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing, 100022, China; State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Bin Li
- Institute of Circular Economy, Beijing University of Technology, Beijing, 100022, China; Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing, 100022, China
| | - Yufeng Wu
- Institute of Circular Economy, Beijing University of Technology, Beijing, 100022, China; Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing, 100022, China.
| | - Shaonan Tian
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Yu Zhang
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Jun Yang
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
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12
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Thomsen TB, Almdal K, Meyer AS. Significance of poly(ethylene terephthalate) (PET) substrate crystallinity on enzymatic degradation. N Biotechnol 2023; 78:162-172. [PMID: 37939899 DOI: 10.1016/j.nbt.2023.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 10/20/2023] [Accepted: 11/04/2023] [Indexed: 11/10/2023]
Abstract
Poly(ethylene terephthalate) (PET) is a semi-crystalline plastic polyester material with a global production volume of 83 Mt/year. PET is mainly used in textiles, but also widely used for packaging materials, notably plastic bottles, and is a major contributor to environmental plastic waste accumulation. Now that enzymes have been demonstrated to catalyze PET degradation, new options for sustainable bio-recycling of PET materials via enzymatic catalysis have emerged. The enzymatic degradation rate is strongly influenced by the properties of PET, notably the degree of crystallinity, XC. The higher the XC of the PET material, the slower the enzymatic rate. Crystallization of PET, resulting in increased XC, is induced thermally (via heating) and/or mechanically (via stretching), and the XC of most PET plastic bottles and microplastics exceeds what currently known enzymes can readily degrade. The enzymatic action occurs at the surface of the insoluble PET material and improves when the polyester chain mobility increases. The chain mobility increases drastically when the temperature exceeds the glass transition temperature, Tg, which is ∼40 °C at the surface layer of PET. Since PET crystallization starts at 70 °C, the ideal temperature for enzymatic degradation is just below 70 °C to balance high chain mobility and enzymatic reaction activation without inducing crystal formation. This paper reviews the current understanding on the properties of PET as an enzyme substrate and summarizes the most recent knowledge of how the crystalline and amorphous regions of PET form, and how the XC and the Tg impact the efficiency of enzymatic PET degradation.
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Affiliation(s)
- Thore Bach Thomsen
- Department of Biotechnology and Biomedicine, DTU Bioengineering, Protein Chemistry and Enzyme Technology Section, Building 221, Technical University of Denmark, 2800 Kgs Lyngby, Denmark
| | - Kristoffer Almdal
- DTU Chemistry, Building 206, Technical University of Denmark, 2800 Kgs Lyngby, Denmark
| | - Anne S Meyer
- Department of Biotechnology and Biomedicine, DTU Bioengineering, Protein Chemistry and Enzyme Technology Section, Building 221, Technical University of Denmark, 2800 Kgs Lyngby, Denmark.
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13
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Scaria SS, Balasubramanian B, Dandin VS, Meyyazhagan A, Pappuswamy M, Sattanathan G, Liu WC, Kadanthottu Sebastian J, Park S. Review on impacts of micro- and nano-plastic on aquatic ecosystems and mitigation strategies. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2023; 265:106759. [PMID: 37977011 DOI: 10.1016/j.aquatox.2023.106759] [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: 09/21/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
The rapid proliferation of microplastics (MPs) and nanoplastics (NPs) in our environment presents a formidable hazard to both biotic and abiotic components. These pollutants originate from various sources, including commercial production and the breakdown of larger plastic particles. Widespread contamination of the human body, agroecosystems, and animals occurs through ingestion, entry into the food chain, and inhalation. Consequently, the imperative to devise innovative methods for MPs and NPs remediation has become increasingly apparent. This review explores the current landscape of strategies proposed to mitigate the escalating threats associated with plastic waste. Among the array of methods in use, microbial remediation emerges as a promising avenue for the decomposition and reclamation of MPs and NPs. In response to the growing concern, numerous nations have already implemented or are in the process of adopting regulations to curtail MPs and NPs in aquatic habitats. This paper aims to address this gap by delving into the environmental fate, behaviour, transport, ecotoxicity, and management of MPs and NPs particles within the context of nanoscience, microbial ecology, and remediation technologies. Key findings of this review encompass the intricate interdependencies between MPs and NPs and their ecosystems. The ecological impact, from fate to ecotoxicity, is scrutinized in light of the burgeoning environmental imperative. As a result, this review not only provides an encompassing understanding of the ecological ramifications of MPs and NPs but also highlights the pressing need for further research, innovation, and informed interventions.
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Affiliation(s)
- Shilpa Susan Scaria
- Department of Life Sciences, Christ University, Bangalore, Karnataka 560029, India
| | | | | | - Arun Meyyazhagan
- Department of Life Sciences, Christ University, Bangalore, Karnataka 560029, India
| | | | | | - Wen-Chao Liu
- Department of Animal Science, College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang 524088, PR China
| | | | - Sungkwon Park
- Department of Food Science and Biotechnology, College of Life Science, Sejong University, Seoul 05006, South Korea.
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14
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Sui B, Wang T, Fang J, Hou Z, Shu T, Lu Z, Liu F, Zhu Y. Recent advances in the biodegradation of polyethylene terephthalate with cutinase-like enzymes. Front Microbiol 2023; 14:1265139. [PMID: 37849919 PMCID: PMC10577388 DOI: 10.3389/fmicb.2023.1265139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Accepted: 09/15/2023] [Indexed: 10/19/2023] Open
Abstract
Polyethylene terephthalate (PET) is a synthetic polymer in the polyester family. It is widely found in objects used daily, including packaging materials (such as bottles and containers), textiles (such as fibers), and even in the automotive and electronics industries. PET is known for its excellent mechanical properties, chemical resistance, and transparency. However, these features (e.g., high hydrophobicity and high molecular weight) also make PET highly resistant to degradation by wild-type microorganisms or physicochemical methods in nature, contributing to the accumulation of plastic waste in the environment. Therefore, accelerated PET recycling is becoming increasingly urgent to address the global environmental problem caused by plastic wastes and prevent plastic pollution. In addition to traditional physical cycling (e.g., pyrolysis, gasification) and chemical cycling (e.g., chemical depolymerization), biodegradation can be used, which involves breaking down organic materials into simpler compounds by microorganisms or PET-degrading enzymes. Lipases and cutinases are the two classes of enzymes that have been studied extensively for this purpose. Biodegradation of PET is an attractive approach for managing PET waste, as it can help reduce environmental pollution and promote a circular economy. During the past few years, great advances have been accomplished in PET biodegradation. In this review, current knowledge on cutinase-like PET hydrolases (such as TfCut2, Cut190, HiC, and LCC) was described in detail, including the structures, ligand-protein interactions, and rational protein engineering for improved PET-degrading performance. In particular, applications of the engineered catalysts were highlighted, such as improving the PET hydrolytic activity by constructing fusion proteins. The review is expected to provide novel insights for the biodegradation of complex polymers.
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Affiliation(s)
- Beibei Sui
- School of Biological Science, Jining Medical University, Jining, Shandong, China
| | - Tao Wang
- School of Biological Science, Jining Medical University, Jining, Shandong, China
| | - Jingxiang Fang
- Rizhao Administration for Market Regulation, Rizhao, Shandong, China
| | - Zuoxuan Hou
- School of Biological Science, Jining Medical University, Jining, Shandong, China
| | - Ting Shu
- School of Biological Science, Jining Medical University, Jining, Shandong, China
| | - Zhenhua Lu
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Fei Liu
- School of Biological Science, Jining Medical University, Jining, Shandong, China
| | - Youshuang Zhu
- School of Biological Science, Jining Medical University, Jining, Shandong, China
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15
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Tseng WS, Lee MJ, Wu JA, Kuo SL, Chang SL, Huang SJ, Liu CT. Poly(butylene adipate-co-terephthalate) biodegradation by Purpureocillium lilacinum strain BA1S. Appl Microbiol Biotechnol 2023; 107:6057-6070. [PMID: 37526695 DOI: 10.1007/s00253-023-12704-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/18/2023] [Accepted: 07/21/2023] [Indexed: 08/02/2023]
Abstract
Poly(butylene adipate-co-terephthalate) (PBAT), a promising biodegradable aliphatic-aromatic copolyester material, can be applied as an alternative material to reduce the adverse effects of conventional plastics. However, the degradation of PBAT plastics in soil is time-consuming, and effective PBAT-degrading microorganisms have rarely been reported. In this study, the biodegradation properties of PBAT by an elite fungal strain and related mechanisms were elucidated. Four PBAT-degrading fungal strains were isolated from farmland soils, and Purpureocillium lilacinum strain BA1S showed a prominent degradation rate. It decomposed approximately 15 wt.% of the PBAT films 30 days after inoculation. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Liquid chromatography mass spectrometry (LC‒MS) were conducted to analyze the physicochemical properties and composition of the byproducts after biodegradation. In the presence of PBAT, the lipolytic enzyme activities of BA1S were remarkably induced, and its cutinase gene was also significantly upregulated. Of note, the utilization of PBAT in BA1S cells was closely correlated with intracellular cytochrome P450 (CYP) monooxygenase. Furthermore, CreA-mediated carbon catabolite repression was confirmed to be involved in regulating PBAT-degrading hydrolases and affected the degradation efficiency. This study provides new insight into the degradation of PBAT by elite fungal strains and increases knowledge on the mechanism, which can be applied to control the biodegradability of PBAT films in the future. KEY POINTS: • Purpureocillium lilacinum strain BA1S was isolated from farmland soils and degraded PBAT plastic films at a prominent rate. • The lipolytic enzyme activities of strain BA1S were induced during coculture with PBAT, and the cutinase gene was significantly upregulated during PBAT degradation. • CreA-mediated carbon catabolite repression of BA1S plays an essential role in regulating the expression of PBAT-degrading hydrolases.
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Affiliation(s)
- Wei-Sung Tseng
- Institute of Biotechnology, National Taiwan University, R412, No. 81, Chang-Xing St, Taipei, 106, Taiwan
| | - Min-Jia Lee
- Institute of Biotechnology, National Taiwan University, R412, No. 81, Chang-Xing St, Taipei, 106, Taiwan
| | - Jin-An Wu
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Shin-Liang Kuo
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Sheng-Lung Chang
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Shu-Jiuan Huang
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Chi-Te Liu
- Institute of Biotechnology, National Taiwan University, R412, No. 81, Chang-Xing St, Taipei, 106, Taiwan.
- Department of Agricultural Chemistry, National Taiwan University No, 1, Sec. Roosevelt Road, Taipei, 106, Taiwan.
- Agricultural Biotechnology Research Center, Academia Sinica, No.128, Sec.2, Academia Rd., Nankang, Taipei, 115, Taiwan.
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16
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Liu F, Wang T, Yang W, Zhang Y, Gong Y, Fan X, Wang G, Lu Z, Wang J. Current advances in the structural biology and molecular engineering of PETase. Front Bioeng Biotechnol 2023; 11:1263996. [PMID: 37795175 PMCID: PMC10546322 DOI: 10.3389/fbioe.2023.1263996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 08/31/2023] [Indexed: 10/06/2023] Open
Abstract
Poly(ethylene terephthalate) (PET) is a highly useful synthetic polyester plastic that is widely used in daily life. However, the increase in postconsumer PET as plastic waste that is recalcitrant to biodegradation in landfills and the natural environment has raised worldwide concern. Currently, traditional PET recycling processes with thermomechanical or chemical methods also result in the deterioration of the mechanical properties of PET. Therefore, it is urgent to develop more efficient and green strategies to address this problem. Recently, a novel mesophilic PET-degrading enzyme (IsPETase) from Ideonella sakaiensis was found to streamline PET biodegradation at 30°C, albeit with a lower PET-degrading activity than chitinase or chitinase-like PET-degrading enzymes. Consequently, the molecular engineering of more efficient PETases is still required for further industrial applications. This review details current knowledge on IsPETase, MHETase, and IsPETase-like hydrolases, including the structures, ligand‒protein interactions, and rational protein engineering for improved PET-degrading performance. In particular, applications of the engineered catalysts are highlighted, including metabolic engineering of the cell factories, enzyme immobilization or cell surface display. The information is expected to provide novel insights for the biodegradation of complex polymers.
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Affiliation(s)
- Fei Liu
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Tao Wang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Wentao Yang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Yingkang Zhang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Yuming Gong
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Xinxin Fan
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Guocheng Wang
- School of Biological Science, Jining Medical University, Rizhao, China
| | - Zhenhua Lu
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jianmin Wang
- School of Pharmacy, Jining Medical University, Rizhao, China
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17
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Blázquez‐Sánchez P, Vargas JA, Furtado AA, Griñen A, Leonardo DA, Sculaccio SA, Pereira HD, Sonnendecker C, Zimmermann W, Díez B, Garratt RC, Ramírez‐Sarmiento CA. Engineering the catalytic activity of an Antarctic PET-degrading enzyme by loop exchange. Protein Sci 2023; 32:e4757. [PMID: 37574805 PMCID: PMC10464292 DOI: 10.1002/pro.4757] [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: 05/16/2023] [Revised: 08/09/2023] [Accepted: 08/10/2023] [Indexed: 08/15/2023]
Abstract
Several hydrolases have been described to degrade polyethylene terephthalate (PET) at moderate temperatures ranging from 25°C to 40°C. These mesophilic PET hydrolases (PETases) are less efficient in degrading this plastic polymer than their thermophilic homologs and have, therefore, been the subject of many protein engineering campaigns. However, enhancing their enzymatic activity through rational design or directed evolution poses a formidable challenge due to the need for exploring a large number of mutations. Additionally, evaluating the improvements in both activity and stability requires screening numerous variants, either individually or using high-throughput screening methods. Here, we utilize instead the design of chimeras as a protein engineering strategy to increase the activity and stability of Mors1, an Antarctic PETase active at 25°C. First, we obtained the crystal structure of Mors1 at 1.6 Å resolution, which we used as a scaffold for structure- and sequence-based chimeric design. Then, we designed a Mors1 chimera via loop exchange of a highly divergent active site loop from the thermophilic leaf-branch compost cutinase (LCC) into the equivalent region in Mors1. After restitution of an active site disulfide bond into this chimera, the enzyme exhibited a shift in optimal temperature for activity to 45°C and an increase in fivefold in PET hydrolysis when compared with wild-type Mors1 at 25°C. Our results serve as a proof of concept of the utility of chimeric design to further improve the activity and stability of PETases active at moderate temperatures.
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Affiliation(s)
- Paula Blázquez‐Sánchez
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological SciencesPontificia Universidad Católica de ChileSantiagoChile
- ANID—Millennium Science Initiative ProgramMillennium Institute for Integrative Biology (iBio)SantiagoChile
- Institute of Analytical ChemistryLeipzig UniversityLeipzigGermany
| | - Jhon A. Vargas
- São Carlos Institute of PhysicsUniversity of São PauloSão CarlosBrazil
| | | | - Aransa Griñen
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological SciencesPontificia Universidad Católica de ChileSantiagoChile
- ANID—Millennium Science Initiative ProgramMillennium Institute for Integrative Biology (iBio)SantiagoChile
| | - Diego A. Leonardo
- São Carlos Institute of PhysicsUniversity of São PauloSão CarlosBrazil
| | | | | | | | | | - Beatriz Díez
- Department of Molecular Genetics and Microbiology, School of Biological SciencesPontificia Universidad Católica de ChileSantiagoChile
- Center for Climate and Resilience Research (CR)SantiagoChile
- Millennium Institute Center for Genome Regulation (CGR)SantiagoChile
| | | | - César A. Ramírez‐Sarmiento
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological SciencesPontificia Universidad Católica de ChileSantiagoChile
- ANID—Millennium Science Initiative ProgramMillennium Institute for Integrative Biology (iBio)SantiagoChile
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18
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Vidal F, Smith S, Williams CK. Ring Opening Copolymerization of Boron-Containing Anhydride with Epoxides as a Controlled Platform to Functional Polyesters. J Am Chem Soc 2023. [PMID: 37311063 DOI: 10.1021/jacs.3c03261] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Boron-functionalized polymers are used in opto-electronics, biology, and medicine. Methods to produce boron-functionalized and degradable polyesters remain exceedingly rare but relevant where (bio)dissipation is required, for example, in self-assembled nanostructures, dynamic polymer networks, and bio-imaging. Here, a boronic ester-phthalic anhydride and various epoxides (cyclohexene oxide, vinyl-cyclohexene oxide, propene oxide, allyl glycidyl ether) undergo controlled ring-opening copolymerization (ROCOP), catalyzed by organometallic complexes [Zn(II)Mg(II) or Al(III)K(I)] or a phosphazene organobase. The polymerizations are well controlled allowing for the modulation of the polyester structures (e.g., by epoxide selection, AB, or ABA blocks), molar masses (9.4 < Mn < 40 kg/mol), and uptake of boron functionalities (esters, acids, "ates", boroxines, and fluorescent groups) in the polymer. The boronic ester-functionalized polymers are amorphous, with high glass transition temperatures (81 < Tg < 224 °C) and good thermal stability (285 < Td < 322 °C). The boronic ester-polyesters are deprotected to yield boronic acid- and borate-polyesters; the ionic polymers are water soluble and degradable under alkaline conditions. Using a hydrophilic macro-initiator in alternating epoxide/anhydride ROCOP, and lactone ring opening polymerization, produces amphiphilic AB and ABC copolyesters. Alternatively, the boron-functionalities are subjected to Pd(II)-catalyzed cross-couplings to install fluorescent groups (BODIPY). The utility of this new monomer as a platform to construct specialized polyesters materials is exemplified here in the synthesis of fluorescent spherical nanoparticles that self-assemble in water (Dh = 40 nm). The selective copolymerization, variable structural composition, and adjustable boron loading represent a versatile technology for future explorations of degradable, well-defined, and functional polymers.
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Affiliation(s)
- Fernando Vidal
- Department of Chemistry, Chemical Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Sevven Smith
- Department of Chemistry, Chemical Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Charlotte K Williams
- Department of Chemistry, Chemical Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
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19
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Hooda S, Mondal P. Insights into the degradation of high-density polyethylene microplastics using microbial strains: Effect of process parameters, degradation kinetics and modeling. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 164:143-153. [PMID: 37059038 DOI: 10.1016/j.wasman.2023.04.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/27/2023] [Accepted: 04/02/2023] [Indexed: 06/19/2023]
Abstract
The extensive distribution of microplastics and their abundance around the world has raised a global concern because of the lack of proper disposal channels as well as poor knowledge of their implications on human health. Sustainable remediation techniques are required owing to the absence of proper disposal methods. The present study explores the deterioration process of high-density polyethylene (HDPE) microplastics using various microbes along with the kinetics and modeling of the process using multiple non-linear regression models. Ten different microbial strains were used for the degradation of microplastics for a period of 30 days. Effect of process parameters on the degradation process was studied with the selected five microbial strains that presented the best degradation results. The reproducibility and efficacy of the process were tested for an extended period of 90 days. Fourier-transform infrared spectroscopy (FTIR) and field emission-scanning electron microscopy (FE-SEM) were used for the analysis of microplastics. Polymer reduction and half-life were evaluated. Pseudomonas putida achieved the maximum degradation efficiency of 12.07% followed by Rhodococcus ruber (11.36%), Pseudomonas stutzeri (8.28%), Bacillus cereus (8.26%), and Brevibacillus borstelensis (8.02%) after 90 days. Out of 14 models tested, 5 were found capable of modeling the process kinetics and based on simplicity and statistical data, Modified Michaelis-Menten model (F8; R2 = 0.97) was selected as superior to others. This study successfully establishes the potential of bioremediation of microplastics as the viable process.
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Affiliation(s)
- Sanjeevani Hooda
- Department of Chemical Engineering, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
| | - Prasenjit Mondal
- Department of Chemical Engineering, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
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20
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Rüthi J, Cerri M, Brunner I, Stierli B, Sander M, Frey B. Discovery of plastic-degrading microbial strains isolated from the alpine and Arctic terrestrial plastisphere. Front Microbiol 2023; 14:1178474. [PMID: 37234546 PMCID: PMC10206078 DOI: 10.3389/fmicb.2023.1178474] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 04/06/2023] [Indexed: 05/28/2023] Open
Abstract
Increasing plastic production and the release of some plastic in to the environment highlight the need for circular plastic economy. Microorganisms have a great potential to enable a more sustainable plastic economy by biodegradation and enzymatic recycling of polymers. Temperature is a crucial parameter affecting biodegradation rates, but so far microbial plastic degradation has mostly been studied at temperatures above 20°C. Here, we isolated 34 cold-adapted microbial strains from the plastisphere using plastics buried in alpine and Arctic soils during laboratory incubations as well as plastics collected directly from Arctic terrestrial environments. We tested their ability to degrade, at 15°C, conventional polyethylene (PE) and the biodegradable plastics polyester-polyurethane (PUR; Impranil®); ecovio® and BI-OPL, two commercial plastic films made of polybutylene adipate-co-terephthalate (PBAT) and polylactic acid (PLA); pure PBAT; and pure PLA. Agar clearing tests indicated that 19 strains had the ability to degrade the dispersed PUR. Weight-loss analysis showed degradation of the polyester plastic films ecovio® and BI-OPL by 12 and 5 strains, respectively, whereas no strain was able to break down PE. NMR analysis revealed significant mass reduction of the PBAT and PLA components in the biodegradable plastic films by 8 and 7 strains, respectively. Co-hydrolysis experiments with a polymer-embedded fluorogenic probe revealed the potential of many strains to depolymerize PBAT. Neodevriesia and Lachnellula strains were able to degrade all the tested biodegradable plastic materials, making these strains especially promising for future applications. Further, the composition of the culturing medium strongly affected the microbial plastic degradation, with different strains having different optimal conditions. In our study we discovered many novel microbial taxa with the ability to break down biodegradable plastic films, dispersed PUR, and PBAT, providing a strong foundation to underline the role of biodegradable polymers in a circular plastic economy.
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Affiliation(s)
- Joel Rüthi
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology ETH, Zurich, Switzerland
| | - Mattia Cerri
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology ETH, Zurich, Switzerland
| | - Ivano Brunner
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Beat Stierli
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Michael Sander
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology ETH, Zurich, Switzerland
| | - Beat Frey
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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21
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Tournier V, Duquesne S, Guillamot F, Cramail H, Taton D, Marty A, André I. Enzymes' Power for Plastics Degradation. Chem Rev 2023; 123:5612-5701. [PMID: 36916764 DOI: 10.1021/acs.chemrev.2c00644] [Citation(s) in RCA: 56] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Plastics are everywhere in our modern way of living, and their production keeps increasing every year, causing major environmental concerns. Nowadays, the end-of-life management involves accumulation in landfills, incineration, and recycling to a lower extent. This ecological threat to the environment is inspiring alternative bio-based solutions for plastic waste treatment and recycling toward a circular economy. Over the past decade, considerable efforts have been made to degrade commodity plastics using biocatalytic approaches. Here, we provide a comprehensive review on the recent advances in enzyme-based biocatalysis and in the design of related biocatalytic processes to recycle or upcycle commodity plastics, including polyesters, polyamides, polyurethanes, and polyolefins. We also discuss scope and limitations, challenges, and opportunities of this field of research. An important message from this review is that polymer-assimilating enzymes are very likely part of the solution to reaching a circular plastic economy.
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Affiliation(s)
- Vincent Tournier
- Carbios, Parc Cataroux-Bâtiment B80, 8 rue de la Grolière, 63100 Clermont-Ferrand, France
| | - Sophie Duquesne
- Toulouse Biotechnology Institute, TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France, 135, avenue de Rangueil, F-31077 Toulouse Cedex 04, France
| | - Frédérique Guillamot
- Carbios, Parc Cataroux-Bâtiment B80, 8 rue de la Grolière, 63100 Clermont-Ferrand, France
| | - Henri Cramail
- Université Bordeaux, CNRS, Bordeaux INP, LCPO, 16 Avenue Pey-Berland, 33600 Pessac, France
| | - Daniel Taton
- Université Bordeaux, CNRS, Bordeaux INP, LCPO, 16 Avenue Pey-Berland, 33600 Pessac, France
| | - Alain Marty
- Carbios, Parc Cataroux-Bâtiment B80, 8 rue de la Grolière, 63100 Clermont-Ferrand, France
| | - Isabelle André
- Toulouse Biotechnology Institute, TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France, 135, avenue de Rangueil, F-31077 Toulouse Cedex 04, France
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22
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Eck M, Schwab ST, Nelson TF, Wurst K, Iberl S, Schleheck D, Link C, Battagliarin G, Mecking S. Biodegradable High-Density Polyethylene-like Material. Angew Chem Int Ed Engl 2023; 62:e202213438. [PMID: 36480133 PMCID: PMC10107712 DOI: 10.1002/anie.202213438] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/18/2022] [Accepted: 12/08/2022] [Indexed: 12/13/2022]
Abstract
We report a novel polyester material generated from readily available biobased 1,18-octadecanedicarboxylic acid and ethylene glycol possesses a polyethylene-like solid-state structure and also tensile properties similar to high density polyethylene (HDPE). Despite its crystallinity, high melting point (Tm =96 °C) and hydrophobic nature, polyester-2,18 is subject to rapid and complete hydrolytic degradation in in vitro assays with isolated naturally occurring enzymes. Under industrial composting conditions (ISO standard 14855-1) the material is biodegraded with mineralization above 95 % within two months. Reference studies with polyester-18,18 (Tm =99 °C) reveal a strong impact of the nature of the diol repeating unit on degradation rates, possibly related to the density of ester groups in the amorphous phase. Depolymerization by methanolysis indicates suitability for closed-loop recycling.
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Affiliation(s)
- Marcel Eck
- Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Simon Timm Schwab
- Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Taylor Frederick Nelson
- Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Katrin Wurst
- Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Steffen Iberl
- Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - David Schleheck
- Microbial Ecology and Limnic Microbiology, Department of Biology, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Christoph Link
- BASF SE, PMD/GB-B001, Carl-Bosch-Strasse 38, 67056, Ludwigshafen am Rhein, Germany
| | - Glauco Battagliarin
- BASF SE, PMD/GB-B001, Carl-Bosch-Strasse 38, 67056, Ludwigshafen am Rhein, Germany
| | - Stefan Mecking
- Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
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23
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Schubert S, Schaller K, Bååth JA, Hunt C, Borch K, Jensen K, Brask J, Westh P. Reaction Pathways for the Enzymatic Degradation of Poly(Ethylene Terephthalate): What Characterizes an Efficient PET-Hydrolase? Chembiochem 2023; 24:e202200516. [PMID: 36399069 PMCID: PMC10108200 DOI: 10.1002/cbic.202200516] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/16/2022] [Accepted: 11/16/2022] [Indexed: 11/19/2022]
Abstract
Bioprocessing of polyester waste has emerged as a promising tool in the quest for a cyclic plastic economy. One key step is the enzymatic breakdown of the polymer, and this entails a complicated pathway with substrates, intermediates, and products of variable size and solubility. We have elucidated this pathway for poly(ethylene terephthalate) (PET) and four enzymes. Specifically, we combined different kinetic measurements and a novel stochastic model and found that the ability to hydrolyze internal bonds in the polymer (endo-lytic activity) was a key parameter for overall enzyme performance. Endo-lytic activity promoted the release of soluble PET fragments with two or three aromatic rings, which, in turn, were broken down with remarkable efficiency (kcat /KM values of about 105 M-1 s-1 ) in the aqueous bulk. This meant that approximatly 70 % of the final, monoaromatic products were formed via soluble di- or tri-aromatic intermediates.
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Affiliation(s)
- Sune Schubert
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
| | - Kay Schaller
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
| | | | - Cameron Hunt
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
| | - Kim Borch
- Novozymes A/S, Biologiens Vej 2, 2800 Kgs., Lyngby, Denmark
| | - Kenneth Jensen
- Novozymes A/S, Biologiens Vej 2, 2800 Kgs., Lyngby, Denmark
| | - Jesper Brask
- Novozymes A/S, Biologiens Vej 2, 2800 Kgs., Lyngby, Denmark
| | - Peter Westh
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs., Lyngby, Denmark
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24
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Santos-Beneit F, Chen LM, Bordel S, Frutos de la Flor R, García-Depraect O, Lebrero R, Rodriguez-Vega S, Muñoz R, Börner RA, Börner T. Screening Enzymes That Can Depolymerize Commercial Biodegradable Polymers: Heterologous Expression of Fusarium solani Cutinase in Escherichia coli. Microorganisms 2023; 11:microorganisms11020328. [PMID: 36838293 PMCID: PMC9963400 DOI: 10.3390/microorganisms11020328] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/12/2023] [Accepted: 01/17/2023] [Indexed: 01/31/2023] Open
Abstract
In recent years, a number of microbial enzymes capable of degrading plastics have been identified. Biocatalytic depolymerization mediated by enzymes has emerged as a potentially more efficient and environmentally friendly alternative to the currently employed methods for plastic treatment and recycling. However, the functional and systematic study of depolymerase enzymes with respect to the degradation of a series of plastic polymers in a single work has not been widely addressed at present. In this study, the ability of a set of enzymes (esterase, arylesterase and cutinase) to degrade commercial biodegradable polymers (PBS, PBAT, PHB, PHBH, PHBV, PCL, PLA and PLA/PCL) and the effect of pre-treatment methods on their degradation rate was assessed. The degradation products were identified and quantified by HPLC and LC-HRMS analysis. Out of the three enzymes, Fusarium solani cutinase (FsCut) showed the highest activity on grinded PBAT, PBS and PCL after 7 days of incubation. FsCut was engineered and heterologous expressed in Escherichia coli, which conferred the bacterium the capability of degrading solid discs of PBAT and to grow in PBS as the sole carbon source of the medium.
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Affiliation(s)
- Fernando Santos-Beneit
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Correspondence: (F.S.-B.); (T.B.)
| | - Le Min Chen
- Nestlé Research, Société des Produits Nestlé S.A, Route du Jorat 57, 1000 Lausanne, Switzerland
| | - Sergio Bordel
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raquel Frutos de la Flor
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Octavio García-Depraect
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raquel Lebrero
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Sara Rodriguez-Vega
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raúl Muñoz
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Rosa Aragão Börner
- Nestlé Research, Société des Produits Nestlé S.A, Route du Jorat 57, 1000 Lausanne, Switzerland
| | - Tim Börner
- Nestlé Research, Société des Produits Nestlé S.A, Route du Jorat 57, 1000 Lausanne, Switzerland
- Correspondence: (F.S.-B.); (T.B.)
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25
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Khare R, Khare S. Polymer and its effect on environment. J INDIAN CHEM SOC 2023. [DOI: 10.1016/j.jics.2022.100821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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26
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Wei S, Zhao Y, Zhou R, Lin J, Su T, Tong H, Wang Z. Biodegradation of polybutylene adipate-co-terephthalate by Priestia megaterium, Pseudomonas mendocina, and Pseudomonas pseudoalcaligenes following incubation in the soil. CHEMOSPHERE 2022; 307:135700. [PMID: 35850225 DOI: 10.1016/j.chemosphere.2022.135700] [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: 06/08/2022] [Revised: 06/29/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Soil that contained polybutylene adipate-co-terephthalate (PBAT) was incubated with Priestia megaterium, Pseudomonas mendocina, and Pseudomonas pseudoalcaligenes to improve the biodegradative process of this polymer. The mixture of Pr. megaterium and Ps. mendocina was highly effective at biodegrading the PBAT, and after eight weeks of soil incubation, approximately 84% of the PBAT film weight was lost. Mixtures of the other two species also positively affected the synergistic degradation of PBAT film in the soil, but the mixture of three species had a negative effect. The residual PBAT film microstructure clearly demonstrated the degradation of PBAT, and the degree of degradation was related to the different species. Cleavage of the PBAT film ester bond after soil microbial action affected its properties. The incubation of PBAT in soil that contained these species affected soil dehydrogenase and soil lipase in particular. The secretion of lipase by these species could play an important role in the degradation of PBAT in the soil.
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Affiliation(s)
- Shiwei Wei
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China
| | - Yujin Zhao
- School of Petrochemical Engineering, Liaoning Petrochemical University, Fushun, 113001, China
| | - Ruimin Zhou
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China
| | - Jingwei Lin
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China
| | - Tingting Su
- School of Petrochemical Engineering, Liaoning Petrochemical University, Fushun, 113001, China
| | - Haibin Tong
- Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection, College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China.
| | - Zhanyong Wang
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China.
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27
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Li R, Cao S, Feng X, Don J, Guo X, Wang H, Zhang Y. Guanidinium-based loose nanofiltration membranes for dye purification and chlorine resistance. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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28
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Bher A, Mayekar PC, Auras RA, Schvezov CE. Biodegradation of Biodegradable Polymers in Mesophilic Aerobic Environments. Int J Mol Sci 2022; 23:12165. [PMID: 36293023 PMCID: PMC9603655 DOI: 10.3390/ijms232012165] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/03/2022] [Accepted: 10/07/2022] [Indexed: 08/29/2023] Open
Abstract
Finding alternatives to diminish plastic pollution has become one of the main challenges of modern life. A few alternatives have gained potential for a shift toward a more circular and sustainable relationship with plastics. Biodegradable polymers derived from bio- and fossil-based sources have emerged as one feasible alternative to overcome inconveniences associated with the use and disposal of non-biodegradable polymers. The biodegradation process depends on the environment's factors, microorganisms and associated enzymes, and the polymer properties, resulting in a plethora of parameters that create a complex process whereby biodegradation times and rates can vary immensely. This review aims to provide a background and a comprehensive, systematic, and critical overview of this complex process with a special focus on the mesophilic range. Activity toward depolymerization by extracellular enzymes, biofilm effect on the dynamic of the degradation process, CO2 evolution evaluating the extent of biodegradation, and metabolic pathways are discussed. Remarks and perspectives for potential future research are provided with a focus on the current knowledge gaps if the goal is to minimize the persistence of plastics across environments. Innovative approaches such as the addition of specific compounds to trigger depolymerization under particular conditions, biostimulation, bioaugmentation, and the addition of natural and/or modified enzymes are state-of-the-art methods that need faster development. Furthermore, methods must be connected to standards and techniques that fully track the biodegradation process. More transdisciplinary research within areas of polymer chemistry/processing and microbiology/biochemistry is needed.
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Affiliation(s)
- Anibal Bher
- School of Packaging, Michigan State University, East Lansing, MI 48824, USA
- Instituto de Materiales de Misiones, CONICET-UNaM, Posadas 3300, Misiones, Argentina
| | - Pooja C. Mayekar
- School of Packaging, Michigan State University, East Lansing, MI 48824, USA
| | - Rafael A. Auras
- School of Packaging, Michigan State University, East Lansing, MI 48824, USA
| | - Carlos E. Schvezov
- Instituto de Materiales de Misiones, CONICET-UNaM, Posadas 3300, Misiones, Argentina
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29
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Hwang DH, Lee ME, Cho BH, Oh JW, You SK, Ko YJ, Hyeon JE, Han SO. Enhanced biodegradation of waste poly(ethylene terephthalate) using a reinforced plastic degrading enzyme complex. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156890. [PMID: 35753492 DOI: 10.1016/j.scitotenv.2022.156890] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/28/2022] [Accepted: 06/18/2022] [Indexed: 06/15/2023]
Abstract
Poly(ethylene terephthalate) (PET) is synthesized via a rich ester bond between terephthalate (TPA) and ethylene glycol (EG). Because of this, PET degradation takes a long time and PET accumulates in the environment. Many studies have been conducted to improve PET degrading enzyme to increase the efficiency of PET depolymerization. However, enzymatic PET decomposition is still restricted, making upcycling and recycling difficult. Here, we report a novel PET degrading complex composed of Ideonella sakaiensis PETase and Candida antarctica lipase B (CALB) that improves degradability, binding ability and enzyme stability. The reaction mechanism of chimeric PETase (cPETase) and chimeric CALB (cCALB) was confirmed by PET and bis (2-hydroxyethyl terephthalate) (BHET). cPETase generated BHET and mono (2-hydroxyethyl terephthalate (MHET) and cCALB produced terephthalate (TPA). Carbohydrate binding module 3 (CBM3) in the scaffolding protein greatly improved PET film binding affinity. Finally, the final enzyme complex demonstrated a 6.5-fold and 8.0-fold increase in the efficiency of hydrolysis from PET with either high crystalline or waste to TPA than single enzymes, respectively. This complex could effectively break down waste PET while maintaining enzyme stability and would be applied for biological upcycling of TPA.
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Affiliation(s)
- Dong-Hyeok Hwang
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Myeong-Eun Lee
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Byeong-Hyeon Cho
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Jun Won Oh
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Seung Kyou You
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Young Jin Ko
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Jeong Eun Hyeon
- Department of Food Science and Biotechnology, College of Knowledge-Based Services Engineering, Sungshin Women's University, Seoul 01133, Republic of Korea; Department of Next Generation Applied Sciences, The Graduate School of Sungshin University, Seoul 01133, Republic of Korea
| | - Sung Ok Han
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea.
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30
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Pothupitiya JU, Zheng C, Saltzman WM. Synthetic biodegradable polyesters for implantable controlled-release devices. Expert Opin Drug Deliv 2022; 19:1351-1364. [PMID: 36197839 DOI: 10.1080/17425247.2022.2131768] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION : Implantable devices can be designed to release drugs to localized regions of tissue at sustained and reliable rates. Advances in polymer engineering have led to the design and development of drug-loaded implants with predictable, desirable release profiles. Biodegradable polyesters exhibit chemical, physical, and biological properties suitable for developing implants for pain management, cancer therapy, contraception, antiviral therapy, and other applications. AREAS COVERED : This article reviews the use of biodegradable polyesters for drug-loaded implants by discussing the properties of commonly used polymers, techniques for implant formulation and manufacturing, mechanisms of drug release, and clinical applications of implants as drug delivery devices. EXPERT OPINION : Drug delivery implants are unique systems for safe and sustained drug release, providing high bioavailability and low toxicity. Depending on the implant design and tissue site of deployment, implants can offer either localized or systemic drug release. Due to the long history of use of degradable polyesters in medical devices, polyester-based implants represent an important class of controlled release technologies. Further, polyester-based implants are the largest category of drug delivery implants to reach the point of testing in humans or approval for human use.
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Affiliation(s)
- Jinal U Pothupitiya
- Department of Biomedical Engineering, Yale University; New Haven, CT 06511, USA
| | - Christy Zheng
- Department of Biomedical Engineering, Yale University; New Haven, CT 06511, USA
| | - W Mark Saltzman
- Department of Biomedical Engineering, Yale University; New Haven, CT 06511, USA
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31
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An NMR look at an engineered PET depolymerase. Biophys J 2022; 121:2882-2894. [PMID: 35794828 PMCID: PMC9388554 DOI: 10.1016/j.bpj.2022.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 06/15/2022] [Accepted: 06/30/2022] [Indexed: 12/30/2022] Open
Abstract
Plastic environmental pollution is a major issue that our generation must face to protect our planet. Plastic recycling has the potential not only to reduce the pollution but also to limit the need for fossil-fuel-based production of new plastics. Enzymes capable of breaking down plastic could thereby support such a circular economy. Polyethylene terephthalate (PET) degrading enzymes have recently attracted considerable interest and have been subjected to intensive enzyme engineering to improve their characteristics. A quadruple mutant of Leaf-branch Compost Cutinase (LCC) was identified as a most efficient and promising enzyme. Here, we use NMR to follow the initial LCC enzyme through its different mutations that lead to its improved performance. We experimentally define the two calcium-binding sites and show their importance on the all-or-nothing thermal unfolding process, which occurs at a temperature of 72°C close to the PET glass transition temperature. Using various NMR probes such as backbone amide, methyl group, and histidine side-chain resonances, we probe the interaction of the enzymes with mono-(2-hydroxyethyl)terephthalic acid. The latter experiments are interpreted in terms of accessibility of the active site to the polymer chain.
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32
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Barcoto MO, Rodrigues A. Lessons From Insect Fungiculture: From Microbial Ecology to Plastics Degradation. Front Microbiol 2022; 13:812143. [PMID: 35685924 PMCID: PMC9171207 DOI: 10.3389/fmicb.2022.812143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/15/2022] [Indexed: 11/13/2022] Open
Abstract
Anthropogenic activities have extensively transformed the biosphere by extracting and disposing of resources, crossing boundaries of planetary threat while causing a global crisis of waste overload. Despite fundamental differences regarding structure and recalcitrance, lignocellulose and plastic polymers share physical-chemical properties to some extent, that include carbon skeletons with similar chemical bonds, hydrophobic properties, amorphous and crystalline regions. Microbial strategies for metabolizing recalcitrant polymers have been selected and optimized through evolution, thus understanding natural processes for lignocellulose modification could aid the challenge of dealing with the recalcitrant human-made polymers spread worldwide. We propose to look for inspiration in the charismatic fungal-growing insects to understand multipartite degradation of plant polymers. Independently evolved in diverse insect lineages, fungiculture embraces passive or active fungal cultivation for food, protection, and structural purposes. We consider there is much to learn from these symbioses, in special from the community-level degradation of recalcitrant biomass and defensive metabolites. Microbial plant-degrading systems at the core of insect fungicultures could be promising candidates for degrading synthetic plastics. Here, we first compare the degradation of lignocellulose and plastic polymers, with emphasis in the overlapping microbial players and enzymatic activities between these processes. Second, we review the literature on diverse insect fungiculture systems, focusing on features that, while supporting insects' ecology and evolution, could also be applied in biotechnological processes. Third, taking lessons from these microbial communities, we suggest multidisciplinary strategies to identify microbial degraders, degrading enzymes and pathways, as well as microbial interactions and interdependencies. Spanning from multiomics to spectroscopy, microscopy, stable isotopes probing, enrichment microcosmos, and synthetic communities, these strategies would allow for a systemic understanding of the fungiculture ecology, driving to application possibilities. Detailing how the metabolic landscape is entangled to achieve ecological success could inspire sustainable efforts for mitigating the current environmental crisis.
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Affiliation(s)
- Mariana O. Barcoto
- Center for the Study of Social Insects, São Paulo State University (UNESP), Rio Claro, Brazil
- Department of General and Applied Biology, São Paulo State University (UNESP), Rio Claro, Brazil
| | - Andre Rodrigues
- Center for the Study of Social Insects, São Paulo State University (UNESP), Rio Claro, Brazil
- Department of General and Applied Biology, São Paulo State University (UNESP), Rio Claro, Brazil
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33
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Chen M, Zhao X, Wu D, Peng L, Fan C, Zhang W, Li Q, Ge C. Addition of biodegradable microplastics alters the quantity and chemodiversity of dissolved organic matter in latosol. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 816:151960. [PMID: 34843778 DOI: 10.1016/j.scitotenv.2021.151960] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 11/05/2021] [Accepted: 11/21/2021] [Indexed: 06/13/2023]
Abstract
Dissolved organic matter (DOM) chemodiversity plays an important role in regulating nutrient cycles and contaminant behavior in soil. However, how biodegradable microplastic (MPs) affect the DOM chemodiversity is still unknown, although developing biodegradable plastics are regarded as a promising strategy to minimize the risks of MPs residues in soil. Here, with the common poly (butylene adipate-co-terephthalate) (PBAT) as the model, the molecular effect of biodegradable MPs on soil DOM was explored by adding 0%, 5% and 10% (w/w) of PBAT to tropical latosol, respectively. The results showed that PBAT addition increased microbial activity and exoenzyme activity (e.g., rhizopus oryzae lipase, invertase and cellulose). As a result, the quantity and chemodiversity of soil DOM were changed. The multispectroscopic characterization showed that PBAT addition significantly increased the DOC molecules in soil, including condensed aromatic-like substances and carbohydrates. In contrast, the TDN molecules with high bioavailability and low aromaticity, such as amino acids, were decreased. The multivariate statistical analysis indicated that there were three mechanisms that drove the shift in DOM chemodiversity. Firstly, the degradation of PBAT by rhizopus oryzae lipase facilitated the release of exogenous aromatic molecules. Secondly, PBAT decomposition stimulated the selective consumption of native N-rich molecules by soil microbes. Thirdly, PBAT accelerated the enzymatic transformation of native aliphatic CHx and cellulose toward humic substances. In addition, concentration effect was also observed in the study that high-concentration PBAT were more likely to trigger the molecular shift in DOM chemodiversity. These findings provided a new insight into the impact of biodegradable MPs on soil DOM chemodiversity at molecular level, which will be beneficial to understanding the fate and biochemical reactivity of DOM in MPs-polluted soil.
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Affiliation(s)
- Miao Chen
- College of Ecology and Environment, Hainan University, Haikou 570228, China; Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Xiongwei Zhao
- College of Ecology and Environment, Hainan University, Haikou 570228, China
| | - Dongming Wu
- Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Licheng Peng
- College of Ecology and Environment, Hainan University, Haikou 570228, China.
| | - Changhua Fan
- Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Wen Zhang
- Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Qinfen Li
- Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China; Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China.
| | - Chengjun Ge
- College of Ecology and Environment, Hainan University, Haikou 570228, China
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Guo B, Vanga SR, Lopez-Lorenzo X, Saenz-Mendez P, Ericsson SR, Fang Y, Ye X, Schriever K, Bäckström E, Biundo A, Zubarev RA, Furó I, Hakkarainen M, Syrén PO. Conformational Selection in Biocatalytic Plastic Degradation by PETase. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05548] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Boyang Guo
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Sudarsana Reddy Vanga
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Ximena Lopez-Lorenzo
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Patricia Saenz-Mendez
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Sara Rönnblad Ericsson
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Yuan Fang
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Xinchen Ye
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Karen Schriever
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Eva Bäckström
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Antonino Biundo
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Roman A. Zubarev
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institute, SE-171 77 Stockholm, Sweden
- SciLifeLab, SE-171 21 Solna, Sweden
- Department of Pharmacological & Technological Chemistry, I.M. Sechenov First Moscow State Medical University, Moscow 119146, Russia
| | - István Furó
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Minna Hakkarainen
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Per-Olof Syrén
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
- Wallenberg Wood Science Center, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
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35
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Tyagi P, Agate S, Velev OD, Lucia L, Pal L. A Critical Review of the Performance and Soil Biodegradability Profiles of Biobased Natural and Chemically Synthesized Polymers in Industrial Applications. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:2071-2095. [PMID: 35077140 DOI: 10.1021/acs.est.1c04710] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This review explores biobased polymers for industrial applications, their end fate, and most importantly, origin and key aspects enabling soil biodegradation. The physicochemical properties of biobased synthetic and natural polymers and the primary factors governing degradation are explored. Current and future biobased systems and factors allowing for equivalent comparisons of degradation and possible sources for engineering improved biodegradation are reviewed. Factors impacting ultraviolet (UV) stability of biopolymers have been described including methods to enhance photoresistance and impact on biodegradation. It discusses end-fate of biopolymers in soil and impact of residues on soil health. A limited number of studies examine side effects (e.g., microbial toxicity) from soil biodegradation of composites and biopolymers. Currently available standards for biodegradation and composting have been described with limitations and scope for improvements. Finally, design considerations and implications for sustainable polymers used, under consideration, and to be considered within the context of a rational biodegradable strategy are elaborated.
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Affiliation(s)
- Preeti Tyagi
- Department of Forest Biomaterials, North Carolina State University, 431 Dan Allen Dr., Raleigh, North Carolina 27695, United States
- Global Breakthrough Packaging Group, Mars Wrigley, Chicago, Illinois 60642, United States
| | - Sachin Agate
- Department of Forest Biomaterials, North Carolina State University, 431 Dan Allen Dr., Raleigh, North Carolina 27695, United States
| | - Orlin D Velev
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695, United States
| | - Lucian Lucia
- Department of Forest Biomaterials, North Carolina State University, 431 Dan Allen Dr., Raleigh, North Carolina 27695, United States
| | - Lokendra Pal
- Department of Forest Biomaterials, North Carolina State University, 431 Dan Allen Dr., Raleigh, North Carolina 27695, United States
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36
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In situ formation of porous organic polymer-based thin polyester membranes for loose nanofiltration. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2021.120074] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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37
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Controllable Preparation of Chiral Oxazoline-Cu(II) Catalyst as Nanoreactor for Highly Asymmetric Henry Reaction in Water. Catal Letters 2022. [DOI: 10.1007/s10562-021-03633-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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38
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Macías SI, Ruano G, Borràs N, Alemán C, Armelin E. UV
assisted photo reactive polyether‐polyesteramide resin for future applications in
3D
printing. JOURNAL OF POLYMER SCIENCE 2021. [DOI: 10.1002/pol.20210626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Steffi I. Macías
- Departament d'Enginyeria Química, EEBE Universitat Politècnica de Catalunya Barcelona Spain
| | - Guillem Ruano
- Departament d'Enginyeria Química, EEBE Universitat Politècnica de Catalunya Barcelona Spain
| | - Núria Borràs
- Departament d'Enginyeria Química, EEBE Universitat Politècnica de Catalunya Barcelona Spain
| | - Carlos Alemán
- Departament d'Enginyeria Química, EEBE Universitat Politècnica de Catalunya Barcelona Spain
- Barcelona Research Center for Multiscale Science, EEBE Barcelona Spain
| | - Elaine Armelin
- Departament d'Enginyeria Química, EEBE Universitat Politècnica de Catalunya Barcelona Spain
- Barcelona Research Center for Multiscale Science, EEBE Barcelona Spain
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39
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Ghodke VM, Punekar NS. Environmental role of aromatic carboxylesterases. Environ Microbiol 2021; 24:2657-2668. [PMID: 34528362 DOI: 10.1111/1462-2920.15774] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 09/08/2021] [Accepted: 09/10/2021] [Indexed: 01/14/2023]
Abstract
The carboxylesterases (EC 3.1.1.x) are widely distributed and form an important yet diverse group of hydrolases catalysing the ester bond cleavage in a variety of substrates. Besides acting on plant cell wall components like cutin, tannin and feruloyl esters, they are often the first line of defence to metabolize drugs, xenobiotics, pesticides, insecticides and plastic. But for the promiscuity of some carboxylesterases and cutinases, very few enzymes act exclusively on aromatic carboxylic acid esters. Infrequent occurrence of aromatic carboxylesterases suggests that aromatic carboxylesters are inherently more difficult to hydrolyse than the regular carboxylesters because of both steric and polar effects. Naturally occurring aromatic carboxylesters were rare before the anthropogenic activity augmented their environmental presence and diversity. An appraisal of the literature shows that the hydrolysis of aromatic carboxylic esters is a uniquely difficult endeavour and hence deserves special attention. Enzymes to hydrolyse such esters are evolving rapidly in nature. Very few such enzymes are known and they often display much lower catalytic efficiencies. Obviously, the esters of aromatic carboxylic acids, including polyethylene terephthalate waste, pose an environmental challenge. In this review, we highlight the uniqueness of aromatic carboxylesters and then underscore the importance of relevant carboxylesterases.
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Affiliation(s)
- Venkatesh M Ghodke
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Narayan S Punekar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
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40
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An integrated overview of bacterial carboxylesterase: Structure, function and biocatalytic applications. Colloids Surf B Biointerfaces 2021; 205:111882. [PMID: 34087776 DOI: 10.1016/j.colsurfb.2021.111882] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 05/21/2021] [Accepted: 05/24/2021] [Indexed: 12/19/2022]
Abstract
Carboxylesterases (CEs) are members of prominent esterase, and as their name imply, they catalyze the cleavage of ester linkages. By far, a considerable number of novel CEs have been identified to investigate their exquisite physiological and biochemical properties. They are abundant enzymes in nature, widely distributed in relatively broad temperature range and in various sources; both macroorganisms and microorganisms. Given the importance of these enzymes in broad industries, interest in the study of their mechanisms and structural-based engineering are greatly increasing. This review presents the current state of knowledge and understanding about the structure and functions of this ester-metabolizing enzyme, primarily from bacterial sources. In addition, the potential biotechnological applications of bacterial CEs are also encompassed. This review will be useful in understanding the molecular basis and structural protein of bacterial CEs that are significant for the advancement of enzymology field in industries.
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41
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Wang J, Zhao X, Wu F, Niu L, Tang Z, Liang W, Zhao T, Fang M, Wang H, Wang X. Characterization, occurrence, environmental behaviors, and risks of nanoplastics in the aquatic environment: Current status and future perspectives. FUNDAMENTAL RESEARCH 2021. [DOI: 10.1016/j.fmre.2021.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Sanchez-Hernandez JC, Ro KS, Szogi AA, Chang S, Park B. Earthworms increase the potential for enzymatic bio-activation of biochars made from co-pyrolyzing animal manures and plastic wastes. JOURNAL OF HAZARDOUS MATERIALS 2021; 408:124405. [PMID: 33168317 DOI: 10.1016/j.jhazmat.2020.124405] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/26/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
We assessed the enzymatic activation of four different biochars produced from pyrolyzing swine manure and poultry litter, and by co-pyrolyzing these livestock residues with agricultural spent mulch plastic film wastes (plastichars). Enzymatic activation consisted of incubating biochars in soil inoculated with earthworms (Lumbricus terrestris), which acted as biological vectors to facilitate retention of extracellular enzymes onto biochar surface. The activity of carboxylesterase ‒a pesticide-detoxifying enzyme‒ was measured in non-bioturbed soils (reference), linings of the burrows created by earthworms, casts (feces) and biochar particles recovered from the soil. Our results revealed that: 1) biochar increased soil carboxylesterase activity respect to biochar-free (control) soils, which was more prominent in the presence of earthworms. 2) The maximum enzyme activity was found in soils amended with plastichars. 3) The plastichars showed higher enzyme binding capacities than that of the biochars produced from animal manure alone, corroborating the pattern of enzyme distribution found in soil. 4) The presence of earthworms in soil significantly increased the potential of the plastichars for enzymatic activation. These findings suggest that the plastichars are suitable for increasing and stabilizing soil enzyme activities with no toxicity on earthworms.
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Affiliation(s)
- Juan C Sanchez-Hernandez
- Laboratory of Ecotoxicology, Institute of Environmental Sciences, University of Castilla-La Mancha, 45071 Toledo, Spain.
| | - Kyoung S Ro
- Coastal Plains Soil, Water & Plant Research Center, Agricultural Research Service, US Department of Agriculture, 2611 West Lucas Street, Florence, SC 29501, USA
| | - Ariel A Szogi
- Coastal Plains Soil, Water & Plant Research Center, Agricultural Research Service, US Department of Agriculture, 2611 West Lucas Street, Florence, SC 29501, USA
| | - Sechin Chang
- Souther Regional Research Center, Agricultural Research Service, US Department of Agriculture, 1100 Robert E. Lee Blvd., New Orleans, LA 70124, USA
| | - Bosoon Park
- National Poultry Research Center, Quality and Safety Assessment Research Unit, 950 College Station Road, Athens, GA 30605, USA
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43
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Zhu B, Wang D, Wei N. Enzyme Discovery and Engineering for Sustainable Plastic Recycling. Trends Biotechnol 2021; 40:22-37. [PMID: 33676748 DOI: 10.1016/j.tibtech.2021.02.008] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 10/22/2022]
Abstract
The drastically increasing amount of plastic waste is causing an environmental crisis that requires innovative technologies for recycling post-consumer plastics to achieve waste valorization while meeting environmental quality goals. Biocatalytic depolymerization mediated by enzymes has emerged as an efficient and sustainable alternative for plastic treatment and recycling. A variety of plastic-degrading enzymes have been discovered from microbial sources. Meanwhile, protein engineering has been exploited to modify and optimize plastic-degrading enzymes. This review highlights the recent trends and up-to-date advances in mining novel plastic-degrading enzymes through state-of-the-art omics-based techniques and improving the enzyme catalytic efficiency and stability via various protein engineering strategies. Future research prospects and challenges are also discussed.
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Affiliation(s)
- Baotong Zhu
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, USA
| | - Dong Wang
- Department of Computer Science and Engineering, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, USA
| | - Na Wei
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, USA.
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Abstract
This short paper reviews two groups of enzymes designated as polyethylene terephthalate (PET) hydrolases: one consists of thermophilic cutinases from thermophilic microorganisms (actinomycetes and a fungus) and the other consists of mesophilic cutinases, the representative of which is IsPETase from a mesophilic bacterium. From the viewpoint that PET hydrolysis requires a high temperature close to the glass transition temperature (65–70 °C in water) of PET, mesophilic cutinases are not suitable for use in the enzymatic recycling of PET since their degradation level is one to three orders of magnitude lower than that of thermophilic cutinases. Many studies have attempted to increase the thermostability of IsPETase by introducing mutations, but even with these modifications, the mesophilic cutinase does not reach the same level of degradation as thermophilic cutinases. In addition, this kind of trial contradicts the claim that IsPETase works at ambient temperature. As plastic pollution is an urgent environmental issue, scientists must focus on feasible thermophilic enzymes for the enzymatic processing of disposed PET, rather than on mesophilic cutinases. Thermophilic and mesophilic cutinases must be evaluated precisely and comparatively, based on their features that enable them to hydrolyze PET, with the aim of enzymatic PET disposal. The level of thermophilic cutinases has already reached their optimal level in PET biorecycling. The optimal level may be reached through the processing of PET waste, by amorphization and micronization into readily hydrolysable forms and the improvement of PET hydrolases by engineering higher degradation ability and low-cost production. Here I summarize the critical points in the evaluation of PET hydrolases and discuss the biorecycling of PET.
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45
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Soulenthone P, Tachibana Y, Suzuki M, Mizuno T, Ohta Y, Kasuya KI. Characterization of a poly(butylene adipate-co-terephthalate) hydrolase from the mesophilic actinobacteria Rhodococcus fascians. Polym Degrad Stab 2021. [DOI: 10.1016/j.polymdegradstab.2021.109481] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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46
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Feng S, Yue Y, Chen J, Zhou J, Li Y, Zhang Q. Biodegradation mechanism of polycaprolactone by a novel esterase MGS0156: a QM/MM approach. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:2332-2344. [PMID: 33146659 DOI: 10.1039/d0em00340a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nowadays micro-plastic pollution has become one of the most serious global environmental problems. A potential strategy in managing micro-plastic waste is enzyme-catalyzed degradation. MGS0156 is a hydrolase screened from environmental metagenomes, which can efficiently degrade commercial plastics such as polycaprolactone, polylactide, etc. Here a combined molecular dynamics, molecular mechanics Poisson-Boltzmann surface area, and quantum mechanics/molecular mechanism method was used to reveal the enzymatic depolymerization mechanism. By systematically analyzing the binding processes of nine oligomers (from a monomer to tetramer), we found that longer oligomers have relatively stronger binding energy. The degradation process involves two concerted elementary steps: triad-assisted nucleophilic attack and C-O bond cleavage. C-O bond cleavage is the rate determining step with an average barrier of 15.7 kcal mol-1, which is consistent with the experimentally determined kcat (1101 s-1, corresponds to 13.3 kcal mol-1). The electrostatic influence analysis of twenty amino acids highlights His231 and Asp237 as potential mutation targets for designing more efficient MGS0156 mutants.
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Affiliation(s)
- Shanshan Feng
- Environment Research Institute, Shandong University, Qingdao, 266200, P. R. China.
| | - Yue Yue
- Environment Research Institute, Shandong University, Qingdao, 266200, P. R. China.
| | - Jinfeng Chen
- Environment Research Institute, Shandong University, Qingdao, 266200, P. R. China.
| | - Jie Zhou
- Environment Research Institute, Shandong University, Qingdao, 266200, P. R. China.
| | - Yanwei Li
- Environment Research Institute, Shandong University, Qingdao, 266200, P. R. China.
| | - Qingzhu Zhang
- Environment Research Institute, Shandong University, Qingdao, 266200, P. R. China.
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47
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Mohanan N, Montazer Z, Sharma PK, Levin DB. Microbial and Enzymatic Degradation of Synthetic Plastics. Front Microbiol 2020; 11:580709. [PMID: 33324366 PMCID: PMC7726165 DOI: 10.3389/fmicb.2020.580709] [Citation(s) in RCA: 262] [Impact Index Per Article: 65.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/20/2020] [Indexed: 12/13/2022] Open
Abstract
Synthetic plastics are pivotal in our current lifestyle and therefore, its accumulation is a major concern for environment and human health. Petroleum-derived (petro-)polymers such as polyethylene (PE), polyethylene terephthalate (PET), polyurethane (PU), polystyrene (PS), polypropylene (PP), and polyvinyl chloride (PVC) are extremely recalcitrant to natural biodegradation pathways. Some microorganisms with the ability to degrade petro-polymers under in vitro conditions have been isolated and characterized. In some cases, the enzymes expressed by these microbes have been cloned and sequenced. The rate of polymer biodegradation depends on several factors including chemical structures, molecular weights, and degrees of crystallinity. Polymers are large molecules having both regular crystals (crystalline region) and irregular groups (amorphous region), where the latter provides polymers with flexibility. Highly crystalline polymers like polyethylene (95%), are rigid with a low capacity to resist impacts. PET-based plastics possess a high degree of crystallinity (30-50%), which is one of the principal reasons for their low rate of microbial degradation, which is projected to take more than 50 years for complete degraded in the natural environment, and hundreds of years if discarded into the oceans, due to their lower temperature and oxygen availability. The enzymatic degradation occurs in two stages: adsorption of enzymes on the polymer surface, followed by hydro-peroxidation/hydrolysis of the bonds. The sources of plastic-degrading enzymes can be found in microorganisms from various environments as well as digestive intestine of some invertebrates. Microbial and enzymatic degradation of waste petro-plastics is a promising strategy for depolymerization of waste petro-plastics into polymer monomers for recycling, or to covert waste plastics into higher value bioproducts, such as biodegradable polymers via mineralization. The objective of this review is to outline the advances made in the microbial degradation of synthetic plastics and, overview the enzymes involved in biodegradation.
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Affiliation(s)
- Nisha Mohanan
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Zahra Montazer
- Faculty of Food Engineering, The Educational Complex of Agriculture and Animal Science, Torbat-e-jam, Iran
| | - Parveen K. Sharma
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - David B. Levin
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, MB, Canada
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48
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Carr CM, Clarke DJ, Dobson ADW. Microbial Polyethylene Terephthalate Hydrolases: Current and Future Perspectives. Front Microbiol 2020; 11:571265. [PMID: 33262744 PMCID: PMC7686037 DOI: 10.3389/fmicb.2020.571265] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 10/19/2020] [Indexed: 12/18/2022] Open
Abstract
Plastic has rapidly transformed our world, with many aspects of human life now relying on a variety of plastic materials. Biological plastic degradation, which employs microorganisms and their degradative enzymes, has emerged as one way to address the unforeseen consequences of the waste streams that have resulted from mass plastic production. The focus of this review is microbial hydrolase enzymes which have been found to act on polyethylene terephthalate (PET) plastic. The best characterized examples are discussed together with the use of genomic and protein engineering technologies to obtain PET hydrolase enzymes for different applications. In addition, the obstacles which are currently limiting the development of efficient PET bioprocessing are presented. By continuing to study the possible mechanisms and the structural elements of key enzymes involved in microbial PET hydrolysis, and by assessing the ability of PET hydrolase enzymes to work under practical conditions, this research will help inform large-scale waste management operations. Finally, the contribution of microbial PET hydrolases in creating a potential circular PET economy will be explored. This review combines the current knowledge on enzymatic PET processing with proposed strategies for optimization and use, to help clarify the next steps in addressing pollution by PET and other plastics.
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Affiliation(s)
- Clodagh M. Carr
- School of Microbiology, University College Cork, Cork, Ireland
| | - David J. Clarke
- School of Microbiology, University College Cork, Cork, Ireland
| | - Alan D. W. Dobson
- School of Microbiology, University College Cork, Cork, Ireland
- SSPC-SFI Research Centre for Pharmaceuticals, University College Cork, Cork, Ireland
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49
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Slavko E, Taylor MS. Site-Selective, Organoboron-Catalyzed Polymerization of Pyranosides: Access to Sugar-Derived Polyesters with Tunable Properties. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01686] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ekaterina Slavko
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Mark S. Taylor
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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50
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Suzuki M, Tachibana Y, Kasuya KI. Biodegradability of poly(3-hydroxyalkanoate) and poly(ε-caprolactone) via biological carbon cycles in marine environments. Polym J 2020. [DOI: 10.1038/s41428-020-00396-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
AbstractApproximately 4.8–12.7 million tons of plastic waste has been estimated to be discharged into marine environments annually by wind and river currents. The Ellen MacArthur Foundation warns that the total weight of plastic waste in the oceans will exceed the total weight of fish in 2050 if the environmental runoff of plastic continues at the current rate. Hence, biodegradable plastics are attracting attention as a solution to the problems caused by plastic waste. Among biodegradable plastics, polyhydroxyalkanoates (PHAs) and poly(ε-caprolactone) (PCL) are particularly noteworthy because of their excellent marine biodegradability. In this review, the biosynthesis of PHA and cutin, a natural analog of PCL, and the biodegradation of PHA and PCL in carbon cycles in marine ecosystems are discussed. PHA is biosynthesized and biodegraded by various marine microbes in a wide range of marine environments, including coastal, shallow-water, and deep-sea environments. Marine cutin is biosynthesized by marine plants or obtained from terrestrial environments, and PCL and cutin are biodegraded by cutin hydrolytic enzyme-producing microbes in broad marine environments. Thus, biological carbon cycles for PHA and PCL exist in the marine environment, which would allow materials made of PHA and PCL to be quickly mineralized in marine environments.
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