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在Vivo生产α分支聚合物的工程
Hongjun Dong, Stephanie Liffland1, Marc A Hillmyer1
1Department of Chemistry , University of Minnesota , Minneapolis , Minnesota 55455 , United States.
Journal of the American Chemical Society
|September 25, 2019
概括
研究人员设计了一种生产分支聚酸 (PHAs) 的途径, 这项工作扩大了PHA途径的实用性,用于创建具有可调节性质的新生物材料.
科学领域:
- 生物技术和聚合物科学
- 可持续材料开发
- 代谢工程
背景情况:
- 聚合物是非常重要的材料, 但可持续的生产和回收仍然是挑战.
- 聚酸 (PHAs) 提供可再生的聚合物来源,但自然单体的多样性限制了材料的特性.
- 工程PHA途径是扩大生物基聚合物的应用的关键.
研究的目的:
- 为生产α-甲基分支多酸盐 (PHAs) 设计一种生物合成途径.
- 识别和表征一种具有增强结合分支单体的能力的PHA聚合酶.
- 通过单体多样化扩大生物基可持续聚合物的特性.
主要方法:
- 对大肠杆菌进行代谢工程,以产生α分支PHA.
- 从活性污泥中识别和描述PHA聚合酶 (CapPhaEC).
- 使用葡萄糖和酸盐作为碳来源的发酵.
- 聚合物的特性,包括分子质量和热性质 (玻璃过渡,化过渡).
主要成果:
- 成功设计的菌株产生了21-36%α分支单体的共聚体.
- 已识别的CapPhaEC聚合酶具有高结合分支单体的能力.
- 生产的聚合物具有1.7-2.0×105gmol-1的重量平均摩尔质量.
- 聚合物是无形的,没有化过渡和低玻璃过渡温度 (-13至-20°C).
结论:
- 设计的途径和确定的聚合酶使得α分支PHAs的生物合成产生.
- 这些新型PHAs与天然对应物相比具有更强的材料特性.
- 这项研究有助于开发先进的生物基可持续聚合物.
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