School of Life Science, Liaoning Normal University, Dalian 116081, China.
Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
Bioresour Technol. 2015 Dec;197:72-8. doi: 10.1016/j.biortech.2015.08.052. Epub 2015 Aug 21.
Escherichia coli cells expressing phenol hydroxylase (designated as PHIND) were used to biosynthesize 1,2-dihydroxydibenzofuran (1,2-dihydroxyDBF) from dibenzofuran (DBF). The pathway of DBF biotransformation by strain PHIND was proposed, in which DBF was initially monohydroxylated at C-1 and C-4 positions to produce 1- and 4-hydroxyDBF, then underwent successive hydroxylation to yield 1,2- and 3,4-dihydroxyDBF, of which 1,2-dihydroxyDBF was identified for the first time. Magnetically immobilized cells of strain PHIND in biphasic systems with dodecane as the solvent presented highest biosynthesis activity for 1,2-dihydroxyDBF, which was a 6.5-fold improvement compared to biosynthesis in aqueous system. The recycling experiments demonstrated that magnetically immobilized cells exhibited higher biosynthesis activity for 1,2-dihydroxyDBF than that by nonmagnetically immobilized cells during five cycles in biphasic systems. These works support the development of an efficient biosynthesis process using magnetically immobilized cells in biphasic systems and provide a promising technique for improving the productivity in 1,2-dihydroxyDBF biosynthesis.
表达苯酚羟化酶（命名为 PHIND）的大肠杆菌细胞被用于从二苯并呋喃（DBF）生物合成 1,2-二羟基二苯并呋喃（1,2-二羟基 DBF）。提出了 PHIND 菌株转化 DBF 的途径，其中 DBF 首先在 C-1 和 C-4 位单羟基化生成 1-和 4-羟基 DBF，然后经历连续羟化生成 1,2-和 3,4-二羟基 DBF，其中 1,2-二羟基 DBF 是首次鉴定的。在以十二烷为溶剂的双相体系中，用磁性固定化 PHIND 菌株的细胞对 1,2-二羟基 DBF 的生物合成活性最高，与在水相中的生物合成相比，提高了 6.5 倍。循环实验表明，在双相体系中，磁性固定化细胞在五个循环中比非磁性固定化细胞具有更高的 1,2-二羟基 DBF 生物合成活性。这些工作支持了在双相体系中使用磁性固定化细胞进行高效生物合成的开发，并为提高 1,2-二羟基 DBF 生物合成的生产力提供了一种有前途的技术。
