{"title":"以乙二醇为原料,不同乙醇酸摩尔分数生物合成聚乙醇酸-氨基-3-羟基丁酸","authors":"Munenori Hayashida , Yosuke Ota , Masayoshi Honda , Sumio Aisawa , Yuji Shibasaki , Hideki Abe , Miwa Yamada","doi":"10.1016/j.polymdegradstab.2025.111502","DOIUrl":null,"url":null,"abstract":"<div><div>Glycolate (GL)-based polyhydroxyalkanoates have potential for biomedical and other applications owing to their high hydrodegradability. Here, we established a biosynthetic pathway for the synthesis of random copolymer poly(glycolate-<em>ran</em>-3-hydroxybutyrate) [P(GL-<em>ran</em>-3HB)] from ethylene glycol (EG) contained in industrial wastes in recombinant <em>Escherichia coli</em>. Recombinant <em>E. coli</em> expressing an engineered polyhydroxyalkanoate (PHA) synthase (PhaC) capable of polymerizing GL, two enzymes providing 3HB monomer (PhaA and PhaB), and three enzymes providing GL monomer from EG (FucO, AldA, and PCT) in a medium containing EG and xylose, produced a GL molar fraction in P(GL-<em>ran</em>-3HB) of 0.24±0.003 mol % maximum. Therefore, we split this method into GL- and polymer synthesis, which enabled the increase of the GL molar fraction from 4.5 to 49.5 mol % in P(GL-<em>ran</em>-3HB)s by initial concentrations of EG in the medium; this indicates that EGs derived from industrial waste have a potential for use in P(GL-<em>ran</em>-3HB) synthesis with a variety of GL molar fractions. P(GL-<em>ran</em>-3HB) biosynthesis with a GL molar fraction exceeding 17 mol % was reported for the first time in this study. Polymer characterization revealed that incorporation of the GL unit slightly increased glass transition temperature and decreased melting temperature and molecular weight of P(GL-<em>ran</em>-3HB). A decrease in crystallinity with increasing GL molar fraction was observed, particularly for polymers with GL molar fractions above 46 mol %, which were almost amorphous. Our findings contribute to the expanding application of EG as a new feedstock for PHAs and broadening the applications of novel PHA copolymers.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"240 ","pages":"Article 111502"},"PeriodicalIF":7.4000,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Biosynthesis of poly(glycolate-ran-3-hydroxybutyrate)s with different glycolate molar fractions from ethylene glycol\",\"authors\":\"Munenori Hayashida , Yosuke Ota , Masayoshi Honda , Sumio Aisawa , Yuji Shibasaki , Hideki Abe , Miwa Yamada\",\"doi\":\"10.1016/j.polymdegradstab.2025.111502\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Glycolate (GL)-based polyhydroxyalkanoates have potential for biomedical and other applications owing to their high hydrodegradability. Here, we established a biosynthetic pathway for the synthesis of random copolymer poly(glycolate-<em>ran</em>-3-hydroxybutyrate) [P(GL-<em>ran</em>-3HB)] from ethylene glycol (EG) contained in industrial wastes in recombinant <em>Escherichia coli</em>. Recombinant <em>E. coli</em> expressing an engineered polyhydroxyalkanoate (PHA) synthase (PhaC) capable of polymerizing GL, two enzymes providing 3HB monomer (PhaA and PhaB), and three enzymes providing GL monomer from EG (FucO, AldA, and PCT) in a medium containing EG and xylose, produced a GL molar fraction in P(GL-<em>ran</em>-3HB) of 0.24±0.003 mol % maximum. Therefore, we split this method into GL- and polymer synthesis, which enabled the increase of the GL molar fraction from 4.5 to 49.5 mol % in P(GL-<em>ran</em>-3HB)s by initial concentrations of EG in the medium; this indicates that EGs derived from industrial waste have a potential for use in P(GL-<em>ran</em>-3HB) synthesis with a variety of GL molar fractions. P(GL-<em>ran</em>-3HB) biosynthesis with a GL molar fraction exceeding 17 mol % was reported for the first time in this study. Polymer characterization revealed that incorporation of the GL unit slightly increased glass transition temperature and decreased melting temperature and molecular weight of P(GL-<em>ran</em>-3HB). A decrease in crystallinity with increasing GL molar fraction was observed, particularly for polymers with GL molar fractions above 46 mol %, which were almost amorphous. Our findings contribute to the expanding application of EG as a new feedstock for PHAs and broadening the applications of novel PHA copolymers.</div></div>\",\"PeriodicalId\":406,\"journal\":{\"name\":\"Polymer Degradation and Stability\",\"volume\":\"240 \",\"pages\":\"Article 111502\"},\"PeriodicalIF\":7.4000,\"publicationDate\":\"2025-06-18\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Polymer Degradation and Stability\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0141391025003313\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"POLYMER SCIENCE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Polymer Degradation and Stability","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0141391025003313","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
Biosynthesis of poly(glycolate-ran-3-hydroxybutyrate)s with different glycolate molar fractions from ethylene glycol
Glycolate (GL)-based polyhydroxyalkanoates have potential for biomedical and other applications owing to their high hydrodegradability. Here, we established a biosynthetic pathway for the synthesis of random copolymer poly(glycolate-ran-3-hydroxybutyrate) [P(GL-ran-3HB)] from ethylene glycol (EG) contained in industrial wastes in recombinant Escherichia coli. Recombinant E. coli expressing an engineered polyhydroxyalkanoate (PHA) synthase (PhaC) capable of polymerizing GL, two enzymes providing 3HB monomer (PhaA and PhaB), and three enzymes providing GL monomer from EG (FucO, AldA, and PCT) in a medium containing EG and xylose, produced a GL molar fraction in P(GL-ran-3HB) of 0.24±0.003 mol % maximum. Therefore, we split this method into GL- and polymer synthesis, which enabled the increase of the GL molar fraction from 4.5 to 49.5 mol % in P(GL-ran-3HB)s by initial concentrations of EG in the medium; this indicates that EGs derived from industrial waste have a potential for use in P(GL-ran-3HB) synthesis with a variety of GL molar fractions. P(GL-ran-3HB) biosynthesis with a GL molar fraction exceeding 17 mol % was reported for the first time in this study. Polymer characterization revealed that incorporation of the GL unit slightly increased glass transition temperature and decreased melting temperature and molecular weight of P(GL-ran-3HB). A decrease in crystallinity with increasing GL molar fraction was observed, particularly for polymers with GL molar fractions above 46 mol %, which were almost amorphous. Our findings contribute to the expanding application of EG as a new feedstock for PHAs and broadening the applications of novel PHA copolymers.
期刊介绍:
Polymer Degradation and Stability deals with the degradation reactions and their control which are a major preoccupation of practitioners of the many and diverse aspects of modern polymer technology.
Deteriorative reactions occur during processing, when polymers are subjected to heat, oxygen and mechanical stress, and during the useful life of the materials when oxygen and sunlight are the most important degradative agencies. In more specialised applications, degradation may be induced by high energy radiation, ozone, atmospheric pollutants, mechanical stress, biological action, hydrolysis and many other influences. The mechanisms of these reactions and stabilisation processes must be understood if the technology and application of polymers are to continue to advance. The reporting of investigations of this kind is therefore a major function of this journal.
However there are also new developments in polymer technology in which degradation processes find positive applications. For example, photodegradable plastics are now available, the recycling of polymeric products will become increasingly important, degradation and combustion studies are involved in the definition of the fire hazards which are associated with polymeric materials and the microelectronics industry is vitally dependent upon polymer degradation in the manufacture of its circuitry. Polymer properties may also be improved by processes like curing and grafting, the chemistry of which can be closely related to that which causes physical deterioration in other circumstances.