Chemo-enzymatic synthesis of polyhydroxyalkanoate by an improved two-phase reaction system (TPRS)
Chemo-enzymatic synthesis of polyhydroxyalkanoate by an improved two-phase reaction system (TPRS)
复制标题
DOI：
10.1016/j.jbiosc.2009.06.004
复制
发表时间：
2009-12-01
影响因子：
2.8
通讯作者：
Munekata, Masanobu
中科院分区：
文献类型：
--
作者：
Han, Xuerong;Satoh, Yasuharu;Munekata, Masanobu
在我们的前期工作中，我们以（R）-3-羟基丁酸噻吩酯[（R）-3HBTP]为前体，采用水-有机溶剂两相反应体系（TPRS）合成了聚-3-羟基丁酸酯[P（3 HB）]。我们开发了一种改进的TPRS用于化学-酶法合成聚羟基烷酸酯（PHA）。在该方法中，巯基乙酸乙酯的乙酰基硫酯（AcETC）用作乙酰CoA（AcCoA）的前体，乙酰CoA是CoA的供体。水相中的CoA与有机溶剂相中的AcETC发生酯交换反应生成AcCoA。水相中的AcCoA和游离3-羟基丁酸（3 HB）通过丙酰CoA转移酶（PCT）的CoA转移反应转化为3 HBCoA和乙酸。合成的3 HBCoA在PHA合成酶的作用下依次聚合，成功地形成了P（3 HB）。在最佳反应条件下，P（3 HB）的最大产率为1.2 g/l，这与体内PHA生产的产率相当。此外，通过构建融合蛋白PCT-PhaC，减少了酶的数量，简化了酶的制备。利用该融合蛋白，通过改进的TPRS，实现了P（3 HB-co-3-hydroxypropionate）和P（3 HB-co-3-mercaptopropionate）的化学-酶促合成。(C)2009年，生物技术学会，日本。All rights reserved.
In our previous paper, we synthesized poly-3-hydroxybutyrate [P(3HB)] by using the water-organic solvent two-phase reaction system (TPRS), in which thiophenyl (R)-3-hydroxybutyrate [(R)-3HBTP] was used as a precursor of 3HBCoA. We have developed an improved TPRS for the chemo-enzymatic synthesis of polyhydroxyalkanoate (PHA). In this method, acetyl thioester of ethyl thioglycolate (AcETC) was used as a precursor of acetylCoA (AcCoA), which was a donor of CoA. The AcCoA was formed by the ester exchange reaction between CoA in the water phase and AcETC in the organic solvent phase. The AcCoA and free 3-hydroxybutyrate (3HB) in the water phase were converted into 3HBCoA and acetate by a CoA transfer reaction of propionylCoA transferase (PCT). The synthesized 3HBCoA was polymerized sequentially by PHA synthase, and P(3HB) was successfully formed. The maximal yield of P(3HB) was 1.2 g/l under the optimal reaction condition; this is comparable to that of in vivo PHA production. Furthermore, the number of enzymes was reduced and enzyme preparation was simplified by the construction of a fusion protein, PCT-PhaC. The chemo-enzymatic synthesis of P(3HB-co-3-hydroxypropionate) and P(3HB-co-3-mercaptopropionate) was also achieved by the improved TPRS using the fusion protein. (C) 2009, The Society for Biotechnology, Japan. All rights reserved.