聚对苯二甲酸酯降解酶的分子改造发展机遇与挑战
Molecular Engineering of PET-Degrading Enzymes: Opportunities and Challenges
塑料污染已成为全球性的环境挑战,其中,聚对苯二甲酸乙二醇酯(PET)作为应用最广泛的合成塑料之一,其高效降解技术的开发对推动塑料废弃物管理和资源化利用至关重要。近年来,研究表明,以PET降解酶为核心的生物催化降解策略可实现PET废弃物的闭环处理。因此,PET降解酶的性能优化已成为该领域的研究重点。本文系统解析了PET降解酶与底物之间的相互作用机制,在此基础上,从定向进化、半理性设计、理性设计和机器学习驱动设计四个方面,综述了PET降解酶的分子改造技术进展,特别强调了机器学习在PET降解酶分子改造中的重要作用,并分析了当前研究面临的重要挑战,包括PET降解酶在低温条件下催化活性不足,限制了其在堆肥等低温环境中的应用;PET降解酶对高结晶度PET的解聚效率较低,难以满足工业化降解需求。针对上述问题,机器学习与酶工程深度融合是未来发展的重要趋势,从而加速高效PET降解酶的开发,突破生物降解技术的产业化瓶颈,推动绿色循环经济的高质量发展。
Plastic pollution has become a pressing global environmental challenge. Polyethylene terephthalate (PET), one of the most widely used synthetic polymers, represents a major contributor to this problem. The development of efficient PET degradation strategies is therefore critical for advancing waste management and resource recovery. Recent studies have demonstrated that biocatalytic approaches, centered on PET-degrading enzymes, can enable closed-loop recycling of PET. As a result, the optimization of PET-degrading enzymes has become a central focus of research in this field. The interaction mechanisms between PET-degrading enzymes and their substrates have been elucidated, providing the foundation for diverse strategies in molecular engineering. Advances have been achieved through directed evolution, semi-rational design, rational design, and more recently, machine-learning-driven approaches. Notably, machine learning has emerged as a transformative tool that accelerates the design of enzymes with enhanced catalytic performance. Despite these advances, major challenges remain. Current PET-degrading enzymes display insufficient activity at low temperatures, limiting their utility in settings such as composting. Moreover, the depolymerization efficiency against highly crystalline PET remains low, hindering industrial-scale application. The convergence of machine learning and enzyme engineering is expected to be a key direction for overcoming these barriers, enabling the development of robust and efficient biocatalysts. Such progress would help break through the bottlenecks in the industrialization of PET biodegradation and promote the transition toward a sustainable circular economy.
PET / 生物降解 / PET降解酶 / 定向进化 / 理性设计 / 机器学习
polyethylene terephthalate / biodegradation / PET-degrading enzymes / directed evolution / rational design / machine learning
| [1] |
Cowger W, Willis K A, Bullock S, et al. Global producer responsibility for plastic pollution [J]. Science Advances, 2024, 10(17): eadj8275. |
| [2] |
He Y H, Deng X L, Jiang L, et al. Current advances, challenges and strategies for enhancing the biodegradation of plastic waste [J]. Science of the Total Environment, 2024, 906: 167850. |
| [3] |
Marfella R, Prattichizzo F, Sardu C, et al. Microplastics and nanoplastics in atheromas and cardiovascular events [J]. New England Journal of Medicine, 2024, 390(10): 900‒910. |
| [4] |
Austin H P, Allen M D, Donohoe B S, et al. Characterization and engineering of a plastic-degrading aromatic polyesterase [J]. PNAS, 2018, 115(19): E4350‒E4357. |
| [5] |
Melchor-Martínez E M, Macías-Garbett R, Alvarado-Ramírez L, et al. Towards a circular economy of plastics: An evaluation of the systematic transition to a new generation of bioplastics [J]. Polymers, 2022, 14(6): 1203. |
| [6] |
Carter L M, MacFarlane C E, Karlock S P, et al. Increased cytoplasmic expression of PETase enzymes in E. coli [J]. Microbial Cell Factories, 2024, 23(1): 319. |
| [7] |
Geyer R, Jambeck J R, Law K L. Production, use, and fate of all plastics ever made [J]. Science Advances, 2017, 3(7): e1700782. |
| [8] |
Kawai F, Kawabata T, Oda M. Current knowledge on enzymatic PET degradation and its possible application to waste stream management and other fields [J]. Applied Microbiology and Biotechnology, 2019, 103(11): 4253‒4268. |
| [9] |
Gao R, Pan H J, Lian J Z. Recent advances in the discovery, characterization, and engineering of poly(ethylene terephthalate) (PET) hydrolases [J]. Enzyme and Microbial Technology, 2021, 150: 109868. |
| [10] |
Carniel A, de Abreu Waldow V, de Castro A M. A comprehensive and critical review on key elements to implement enzymatic PET depolymerization for recycling purposes [J]. Biotechnology Advances, 2021, 52: 107811. |
| [11] |
Maurya A, Bhattacharya A, Khare S K. Enzymatic remediation of polyethylene terephthalate (PET)—Based polymers for effective management of plastic wastes: An overview [J]. Frontiers in Bioengineering and Biotechnology, 2020, 8: 602325. |
| [12] |
Thomsen T B, Almdal K, Meyer A S. Significance of poly(ethylene terephthalate) (PET) substrate crystallinity on enzymatic degradation [J]. New Biotechnology, 2023, 78: 162‒172. |
| [13] |
Lu H Y, Diaz D J, Czarnecki N J, et al. Machine learning-aided engineering of hydrolases for PET depolymerization [J]. Nature, 2022, 604(7907): 662‒667. |
| [14] |
Tournier V, Topham C M, Gilles A, et al. An engineered PET depolymerase to break down and recycle plastic bottles [J]. Nature, 2020, 580(7802): 216‒219. |
| [15] |
Meyer Cifuentes I E, Wu P, Zhao Y P, et al. Molecular and biochemical differences of the tandem and cold-adapted PET hydrolases Ple628 and Ple629, isolated from a marine microbial consortium [J]. Frontiers in Bioengineering and Biotechnology, 2022, 10: 930140. |
| [16] |
Sulaiman S, Yamato S, Kanaya E, et al. Isolation of a novel cutinase homolog with polyethylene terephthalate-degrading activity from leaf-branch compost by using a metagenomic approach [J]. Applied and Environmental Microbiology, 2012, 78(5): 1556‒1562. |
| [17] |
Zimmermann W, Wei R, Hille P, et al. New polypeptides having a polyester degrading activity and uses thereof: EP3517608A1 [P/OL]. 2019-07-31[2025-06-10]. https://xueshu.baidu.com/usercenter/paper/show?paperid=144j0eb02w5p0gd0594q0jc0gc327086. |
| [18] |
Müller R J, Schrader H, Profe J, et al. Enzymatic degradation of poly(ethylene terephthalate): Rapid hydrolyse using a hydrolase from T. fusca [J]. Macromolecular Rapid Communications, 2005, 26(17): 1400‒1405. |
| [19] |
Chertkov O, Sikorski J, Nolan M, et al. Complete genome sequence of Thermomonospora curvata type strain (B9) [J]. Standards in Genomic Sciences, 2011, 4(1): 13‒22. |
| [20] |
Ribitsch D, Heumann S, Trotscha E, et al. Hydrolysis of polyethyleneterephthalate by p-nitrobenzylesterase from Bacillus subtilis [J]. Biotechnology Progress, 2011, 27(4): 951‒960. |
| [21] |
Yoshida A, Okutsu I, Hamanaka I. Endoscopic tarsal tunnel syndrome surgery using the Universal Subcutaneous Endoscope system [J]. Asia-Pacific Journal of Sports Medicine, Arthroscopy, Rehabilitation and Technology, 2016, 3: 1‒5. |
| [22] |
Son H, Cho I J, Joo S, et al. Rational protein engineering of thermo-stable PETase from ideonella sakaiensis for highly efficient PET degradation [J]. ACS Catalysis, 2019, 9(4): 3519‒3526. |
| [23] |
Danso D, Schmeisser C, Chow J, et al. New insights into the function and global distribution of polyethylene terephthalate (PET)-degrading bacteria and enzymes in marine and terrestrial metagenomes [J]. Applied and Environmental Microbiology, 2018, 84(8): e02773‒17. |
| [24] |
de Castro A M, Carniel A. A novel process for poly(ethylene terephthalate) depolymerization via enzyme-catalyzed glycolysis [J]. Biochemical Engineering Journal, 2017, 124: 64‒68. |
| [25] |
Shirke A N, White C, Englaender J A, et al. Stabilizing leaf and branch compost cutinase (LCC) with glycosylation: Mechanism and effect on PET hydrolysis [J]. Biochemistry, 2018, 57(7): 1190‒1200. |
| [26] |
Xi X X, Ni K F, Hao H L, et al. Secretory expression in Bacillus subtilis and biochemical characterization of a highly thermostable polyethylene terephthalate hydrolase from bacterium HR29 [J]. Enzyme and Microbial Technology, 2021, 143: 109715. |
| [27] |
Cui Y L, Chen Y C, Sun J Y, et al. Computational redesign of a hydrolase for nearly complete PET depolymerization at industrially relevant high-solids loading [J]. Nature Communications, 2024, 15: 1417. |
| [28] |
Sonnendecker C, Oeser J, Richter P K, et al. Low carbon footprint recycling of post-consumer PET plastic with a metagenomic polyester hydrolase [J]. ChemSusChem, 2022, 15(9): e202101062. |
| [29] |
Makryniotis K, Nikolaivits E, Gkountela C, et al. Discovery of a polyesterase from Deinococcus maricopensis and comparison to the benchmark LCCICCG suggests high potential for semi-crystalline post-consumer PET degradation [J]. Journal of Hazardous Materials, 2023, 455: 131574. |
| [30] |
Seo H, Hong H, Park J, et al. Landscape profiling of PET depolymerases using a natural sequence cluster framework [J]. Science, 2025, 387(6729): eadp5637. |
| [31] |
Tournier V, Duquesne S, Guillamot F, et al. Enzymes' power for plastics degradation [J]. Chemical Reviews, 2023, 123(9): 5612‒5701. |
| [32] |
Fecker T, Galaz-Davison P, Engelberger F, et al. Active site flexibility as a hallmark for efficient PET degradation by I. sakaiensis PETase [J]. Biophysical Journal, 2018, 114(6): 1302‒1312. |
| [33] |
Roth C, Wei R, Oeser T, et al. Structural and functional studies on a thermostable polyethylene terephthalate degrading hydrolase from Thermobifida fusca [J]. Applied Microbiology and Biotechnology, 2014, 98(18): 7815‒7823. |
| [34] |
Qiu J R, Chen Y X, Zhang L Q, et al. A comprehensive review on enzymatic biodegradation of polyethylene terephthalate [J]. Environmental Research, 2024, 240: 117427. |
| [35] |
Sagong H Y, Kim S, Lee D, et al. Structural and functional characterization of an auxiliary domain-containing PET hydrolase from Burkholderiales bacterium [J]. Journal of Hazardous Materials, 2022, 429: 128267. |
| [36] |
Wei R, Oeser T, Barth M, et al. Turbidimetric analysis of the enzymatic hydrolysis of polyethylene terephthalate nanoparticles [J]. Journal of Molecular Catalysis B: Enzymatic, 2014, 103: 72‒78. |
| [37] |
Araújo R, Silva C, O'Neill A, et al. Tailoring cutinase activity towards polyethylene terephthalate and polyamide 6, 6 fibers [J]. Journal of Biotechnology, 2007, 128(4): 849‒857. |
| [38] |
Wei R, Oeser T, Zimmermann W. Synthetic polyester-hydrolyzing enzymes from thermophilic actinomycetes [J]. Advances in Applied Microbiology, 2014, 89: 267‒305. |
| [39] |
Zheng M N, Li Y W, Dong W L, et al. Depolymerase-catalyzed polyethylene terephthalate hydrolysis: A unified mechanism revealed by quantum mechanics/molecular mechanics analysis [J]. ACS Sustainable Chemistry & Engineering, 2022, 10(22): 7341‒7348. |
| [40] |
Joo S, Cho I J, Seo H, et al. Structural insight into molecular mechanism of poly(ethylene terephthalate) degradation [J]. Nature Communications, 2018, 9: 382. |
| [41] |
Shi D D, Arnaout O, Bi W L, et al. Severe radiation necrosis refractory to surgical resection in patients with melanoma and brain metastases managed with ipilimumab/nivolumab and brain-directed stereotactic radiation therapy [J]. World Neurosurgery, 2020, 139: 226‒231. |
| [42] |
Buller A R, Townsend C A. Intrinsic evolutionary constraints on protease structure, enzyme acylation, and the identity of the catalytic triad [J]. PNAS, 2013, 110(8): E653‒E661. |
| [43] |
Han X, Liu W D, Huang J W, et al. Structural insight into catalytic mechanism of PET hydrolase [J]. Nature Communications, 2017, 8: 2106. |
| [44] |
Hutchison C A, Phillips S, Edgell M H, et al. Mutagenesis at a specific position in a DNA sequence [J]. Journal of Biological Chemistry, 1978, 253(18): 6551‒6560. |
| [45] |
Trevizano L M, Ventorim R Z, de Rezende S T, et al. Thermostability improvement of Orpinomyces sp. xylanase by directed evolution [J]. Journal of Molecular Catalysis B: Enzymatic, 2012, 81: 12‒18. |
| [46] |
Shi L X, Liu P, Tan Z J, et al. Complete depolymerization of PET wastes by an evolved PET hydrolase from directed evolution [J]. Angewandte Chemie International Edition, 2023, 62(14): e202218390. |
| [47] |
Jiang K Y, Yan Z Q, Di Bernardo M, et al. Rapid in silico directed evolution by a protein language model with EVOLVEpro [J]. Science, 2025, 387(6732): eadr6006. |
| [48] |
Chen L, Zhang Z H, Li Z H, et al. Learning protein fitness landscapes with deep mutational scanning data from multiple sources [J]. Cell Systems, 2023, 14(8): 706‒721. |
| [49] |
Brott S, Pfaff L, Schuricht J, et al. Engineering and evaluation of thermostable IsPETase variants for PET degradation [J]. Engineering in Life Sciences, 2022, 22(3/4): 192‒203. |
| [50] |
Wang X T, Song C Y, Qi Q S, et al. Biochemical characterization of a polyethylene terephthalate hydrolase and design of high-throughput screening for its directed evolution [J]. Engineering Microbiology, 2022, 2(2): 100020. |
| [51] |
Wittmann B J, Johnston K E, Wu Z, et al. Advances in machine learning for directed evolution [J]. Current Opinion in Structural Biology, 2021, 69: 11‒18. |
| [52] |
Yang K K, Wu Z, Arnold F H. Machine-learning-guided directed evolution for protein engineering [J]. Nature Methods, 2019, 16(8): 687‒694. |
| [53] |
Wang Y J, Xue P, Cao M F, et al. Directed evolution: Methodologies and applications [J]. Chemical Reviews, 2021, 121(20): 12384‒12444. |
| [54] |
Pfaff L, Gao J, Li Z S, et al. Multiple substrate binding mode-guided engineering of a thermophilic PET hydrolase [J]. ACS Catalysis, 2022, 12(15): 9790‒9800. |
| [55] |
Nezhad N G, Raja Noor Zaliha Raja Abd Rahman, Normi Y M, et al. Recent advances in simultaneous thermostability-activity improvement of industrial enzymes through structure modification [J]. International Journal of Biological Macromolecules, 2023, 232: 123440. |
| [56] |
Damborsky J, Brezovsky J. Computational tools for designing and engineering enzymes [J]. Current Opinion in Chemical Biology, 2014, 19: 8‒16. |
| [57] |
Abramson J, Adler J, Dunger J, et al. Accurate structure prediction of biomolecular interactions with AlphaFold 3 [J]. Nature, 2024, 630(8016): 493‒500. |
| [58] |
Nakamura A, Kobayashi N, Koga N, et al. Positive charge introduction on the surface of thermostabilized PET hydrolase facilitates PET binding and degradation [J]. ACS Catalysis, 2021, 11(14): 8550‒8564. |
| [59] |
Zheng Y, Li Q B, Liu P, et al. Dynamic docking-assisted engineering of hydrolases for efficient PET depolymerization [J]. ACS Catalysis, 2024, 14(5): 3627‒3639. |
| [60] |
Notin P, Rollins N, Gal Y, et al. Machine learning for functional protein design [J]. Nature Biotechnology, 2024, 42(2): 216‒228. |
| [61] |
Meier J, Rao R, Verkuil R, et al. Language models enable zero-shot prediction of the effects of mutations on protein function [R]. New York: Proceedings of the 35th International Conference on Neural Information Processing Systems, 2021. |
| [62] |
Lin Z M, Akin H, Rao R, et al. Evolutionary-scale prediction of atomic-level protein structure with a language model [J]. Science, 2023, 379(6637): 1123‒1130. |
| [63] |
Rives A, Meier J, Sercu T, et al. Biological structure and function emerge from scaling unsupervised learning to 250 million protein sequences [J]. PNAS, 2021, 118(15): e2016239118. |
| [64] |
Yang K K, Fusi N, Lu A X. Convolutions are competitive with transformers for protein sequence pretraining [J]. Cell Systems, 2024, 15(3): 286‒294.e2. |
| [65] |
Madani A, Krause B, Greene E R, et al. Large language models generate functional protein sequences across diverse families [J]. Nature Biotechnology, 2023, 41(8): 1099‒1106. |
| [66] |
Ferruz N, Schmidt S, Höcker B. ProtGPT2 is a deep unsupervised language model for protein design [J]. Nature Communications, 2022, 13: 4348. |
| [67] |
Alley E C, Khimulya G, Biswas S, et al. Unified rational protein engineering with sequence-based deep representation learning [J]. Nature Methods, 2019, 16(12): 1315‒1322. |
| [68] |
Elnaggar A, Heinzinger M, Dallago C, et al. ProtTrans: Toward understanding the language of life through self-supervised learning [J]. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2022, 44(10): 7112‒7127. |
| [69] |
Brandes N, Ofer D, Peleg Y, et al. ProteinBERT: A universal deep-learning model of protein sequence and function [J]. Bioinformatics, 2022, 38(8): 2102‒2110. |
| [70] |
Heinzinger M, Elnaggar A, Wang Y, et al. Modeling aspects of the language of life through transfer-learning protein sequences [J]. BMC Bioinformatics, 2019, 20(1): 723. |
| [71] |
Stärk H, Dallago C, Heinzinger M, et al. Light attention predicts protein location from the language of life [J]. Bioinformatics Advances, 2021, 1(1): vbab035. |
| [72] |
Menke M J, Ao Y F, Bornscheuer U T. Practical machine learning-assisted design protocol for protein engineering: Transaminase engineering for the conversion of bulky substrates [J]. ACS Catalysis, 2024, 14(9): 6462‒6469. |
| [73] |
Anand N, Eguchi R, Huang P S. Fully differentiable full-atom protein back-bone generation [R]. New Orleans: The International Conference on Learning Representations (ICLR) Workshops: DeepGenStruct, 2019. |
| [74] |
Eguchi R R, Choe C A, Huang P S. Ig-VAE: Generative modeling of protein structure by direct 3D coordinate generation [J]. PLoS Computational Biology, 2022, 18(6): e1010271. |
| [75] |
Watson J L, Juergens D, Bennett N R, et al. De novo design of protein structure and function with RFdiffusion [J]. Nature, 2023, 620(7976): 1089‒1100. |
| [76] |
Ingraham J B, Baranov M, Costello Z, et al. Illuminating protein space with a programmable generative model [J]. Nature, 2023, 623(7989): 1070‒1078. |
| [77] |
Wu K E, Yang K K, van den Berg R, et al. Protein structure generation via folding diffusion [J]. Nature Communications, 2024, 15: 1059. |
| [78] |
Anishchenko I, Pellock S J, Chidyausiku T M, et al. De novo protein design by deep network hallucination [J]. Nature, 2021, 600(7889): 547‒552. |
| [79] |
Wang J, Lisanza S, Juergens D, et al. Scaffolding protein functional sites using deep learning [J]. Science, 2022, 377(6604): 387‒394. |
| [80] |
Wicky B I M, Milles L F, Courbet A, et al. Hallucinating symmetric protein assemblies [J]. Science, 2022, 378(6615): 56‒61. |
| [81] |
Li X, Huang J W, Ning Z Y, et al. Combined approaches to enhance the Pichia pastoris-expressed PET hydrolase [J]. International Journal of Biological Macromolecules, 2025, 320: 145862. |
| [82] |
Kosiorowska K E, Moreno A D, Iglesias R, et al. Streamlining biological recycling of poly(ethylene terephthalate) via pre-treatment methods [J]. International Biodeterioration & Biodegradation, 2024, 193: 105842. |
| [83] |
Giraldo-Narcizo S, Guenani N, Sánchez-Pérez A M, et al. Accelerated polyethylene terephthalate (PET) enzymatic degradation by room temperature alkali pre-treatment for reduced polymer crystallinity [J]. ChemBioChem, 2023, 24(1): e202200503. |
中国工程院咨询项目“我国化工新材料绿色低碳发展战略研究”(2024-XBZD-09)
国家重点研发计划项目(2023YFA0913600)
国家自然科学基金项目(22425803)
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