One-step fermentative production of poly(lactate-co-glycolate) from carbohydrates in Escherichia coli
One-step fermentative production of poly(lactate-co-glycolate) from carbohydrates in Escherichia coli
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DOI：
10.1038/nbt.3485
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发表时间：
2016-04-01
影响因子：
46.9
通讯作者：
Lee, Sang Yup
中科院分区：
文献类型：
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作者：
Choi, So Young;Park, Si Jae;Lee, Sang Yup
聚乳酸-羟基乙酸共聚物（PLGA）是一种广泛应用的生物可降解和生物相容性合成聚合物。在这里，我们报告了一步发酵生产的PLGA在工程大肠杆菌窝藏进化的聚羟基链烷酸酯（PHA）合成酶，聚合D-乳酰辅酶A和乙醇酰辅酶A到PLGA。Dahms途径的引入使得能够从木糖生产乙醇酸盐。ptsG的缺失使得能够同时利用葡萄糖和木糖。一种进化的丙酰辅酶A转移酶将D-乳酸和乙醇酸分别转化为D-乳酰辅酶A和乙醇酰辅酶A。adhE、frdB、pflB和poxB的缺失防止副产物形成。我们还证明了通过过表达ldhA和删除dld以增加D-乳酸盐的比例或通过删除aceB、glcB、glcD、glcE、glcF和glcG以增加乙醇酸盐的比例来调节PLGA中的单体组分。通过删除ilvA或用l-异亮氨酸喂养菌株来防止2-羟基丁酸的掺入。我们的方法用于产生不同形式的PLGA的效用通过含有3-羟基丁酸酯、4-羟基丁酸酯或2-羟基异戊酸酯的共聚物的生产来显示。
Poly(lactate-co-glycolate) (PLGA) is a widely used biodegradable and biocompatible synthetic polymer. Here we report one-step fermentative production of PLGA in engineered Escherichia coli harboring an evolved polyhydroxyalkanoate (PHA) synthase that polymerizes D-lactyl-CoA and glycolyl-CoA into PLGA. Introduction of the Dahms pathway enables production of glycolate from xylose. Deletion of ptsG enables simultaneous utilization of glucose and xylose. An evolved propionyl-CoA transferase converts D-lactate and glycolate to D-lactyl-CoA and glycolyl-CoA, respectively. Deletion of adhE, frdB, pflB and poxB prevents by-product formation. We also demonstrate modulation of the monomer fractions in PLGA by overexpressing ldhA and deleting dld to increase the proportion of D-lactate or by deleting aceB, glcB, glcD, glcE, glcF and glcG to increase the proportion of glycolate. Incorporation of 2-hydroxybutyrate is prevented by deleting ilvA or feeding strains with l-isoleucine. The utility of our approach for generating diverse forms of PLGA is shown by the production of copolymers containing 3-hydroxybutyrate, 4-hydroxybutyrate or 2-hydroxyisovalerate.