Phenylalanine biosynthesis in Brevibacterium lactofermentum using Escherichia coli genes pheA , aroG and tyrB

<正> Genetic engineering technology to increase the production of L-phenylalanine was used in the study. Three genes encoding the key enzymes involved in the biosynthesis of L-phenylalanine were utilized, in which the gene aroG encodes 3-deoxy-D-arabino-heptulosonate-7-phosphate synthetase (DS); the gene pheA encodes bifunctional enzyme of chorisate mutase (CM) and prephenate dehydratase (PD); and the gene tyrb encodes aminotransferase (AT). The three genes were amplified by polymerase chain reaction (PCR) from the genome of the E. coli mutant strains resistant to fluro-DL-phenylalanine and inserted into the cloning vectors. Then, they were expressed in E. coli and Bre-vibacterium lactofermentum in a tandem arrangement. The expressed enzymes had high activities in the host cells.