Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China.
World J Microbiol Biotechnol. 2021 Jan 4;37(1):2. doi: 10.1007/s11274-020-02986-0.
Polyhydroxyalkanoates (PHAs) are a class of high-molecular-weight polyesters made from hydroxy fatty acid monomers. PHAs produced by microorganisms have diverse structures, variable physical properties, and good biodegradability. They exhibit similar physical properties to petroleum-based plastics but are much more environmentally friendly. Medium-chain-length polyhydroxyalkanoates (mcl-PHAs), in particular, have attracted much interest because of their low crystallinity, low glass transition temperature, low tensile strength, high elongation at break, and customizable structure. Nevertheless, high production costs have hindered their practical application. The use of genetically modified organisms can reduce production costs by expanding the scope of substrate utilization, improving the conversion efficiency of substrate to product, and increasing the yield of mcl-PHAs. The yield of mcl-PHAs produced by a pure culture of an engineered microorganism was not high enough because of the limitations of the metabolic capacity of a single microorganism. The construction of artificial microbial consortia and the optimization of microbial co-cultivation have been studied. This type of approach avoids the addition of precursor substances and helps synthesize mcl-PHAs more efficiently. In this paper, we reviewed the design and construction principles and optimized control strategies for artificial microbial consortia that produce mcl-PHAs. We described the metabolic advantages of co-cultivating artificial microbial consortia using low-value substrates and discussed future perspectives on the production of mcl-PHAs using artificial microbial consortia.
聚羟基脂肪酸酯（PHAs）是由羟基脂肪酸单体组成的高分子量聚酯。微生物产生的 PHAs 具有不同的结构、可变的物理性质和良好的生物降解性。它们具有与石油基塑料相似的物理性质，但更环保。特别是中链长聚羟基脂肪酸酯（mcl-PHAs）因其低结晶度、低玻璃化转变温度、低拉伸强度、高断裂伸长率和可定制结构而引起了广泛关注。然而，高生产成本阻碍了它们的实际应用。通过扩大底物利用范围、提高底物到产物的转化率以及增加 mcl-PHAs 的产量，可以利用基因工程改造的生物体来降低生产成本。由于单个微生物的代谢能力有限，工程微生物的纯培养物生产的 mcl-PHAs 的产量不够高。已经研究了人工微生物群落的构建和微生物共培养的优化。这种方法避免了前体物质的添加，有助于更有效地合成 mcl-PHAs。本文综述了生产 mcl-PHAs 的人工微生物群落的设计和构建原则以及优化控制策略。我们描述了利用低价值底物共培养人工微生物群落的代谢优势，并讨论了利用人工微生物群落生产 mcl-PHAs 的未来展望。
