Tamaki Shun, Yagi Mitsuhiko, Nishihata Yuki, Yamaji Hideki, Shigeri Yasushi, Uno Tomohide, Imaishi Hiromasa
Division of Signal Responses, Biosignal Research Center, Kobe University, Nada, Kobe 657-8501, Japan.
Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, Nada, Kobe 657-8501, Japan.
J Microbiol Biotechnol. 2018 Mar 28;28(3):439-447. doi: 10.4014/jmb.1711.11030.
The aromatic compound -hydroxybenzoate (PHBA) is an important material with multiple applications, including as a building block of liquid crystal polymers in chemical industries. The cytochrome P450 (CYP) enzymes are beneficial monooxygenases for the synthesis of chemicals, and CYP53A15 from fungus is capable of executing the hydroxylation from benzoate to PHBA. Here, we constructed a system for the bioconversion of benzoate to PHBA in cells coexpressing and human NADPH-P450 oxidoreductase () genes as a redox partner. For suitable coexpression of and , we originally constructed five plasmids in which we replaced the N-terminal transmembrane region of CYP53A15 with a portion of the N-terminus of various mammalian P450s. PHBA productivity was the greatest when expression was induced at 20°C in 2×YT medium in host strain Δ transformed with an N-terminal transmembrane region of rabbit CYP2C3. By optimizing each reaction condition (reaction temperature, substrate concentration, reaction time, and cell concentration), we achieved 90% whole-cell conversion of benzoate. Our data demonstrate that the described novel bioconversion system is a more efficient tool for PHBA production from benzoate than the previously described yeast system.
芳香族化合物对羟基苯甲酸(PHBA)是一种具有多种应用的重要物质,包括作为化学工业中液晶聚合物的一个组成部分。细胞色素P450(CYP)酶是用于化学品合成的有益单加氧酶,来自真菌的CYP53A15能够催化苯甲酸向PHBA的羟基化反应。在此,我们构建了一个在共表达CYP53A15和人NADPH - P450氧化还原酶(POR)基因作为氧化还原伴侣的细胞中,将苯甲酸生物转化为PHBA的系统。为了实现CYP53A15和POR的合适共表达,我们最初构建了五个质粒,其中我们用各种哺乳动物P450的N端的一部分替换了CYP53A15的N端跨膜区域。当在20°C下于2×YT培养基中诱导表达时,在用兔CYP2C3的N端跨膜区域转化的宿主大肠杆菌Δ菌株中,PHBA的产量最高。通过优化每个反应条件(反应温度、底物浓度、反应时间和大肠杆菌细胞浓度),我们实现了苯甲酸90%的全细胞转化率。我们的数据表明,所描述的新型生物转化系统是一种比先前描述的酵母系统更有效的从苯甲酸生产PHBA的工具。