Cloning Of Phosphoserine Aminotransferase Gene Of Escherichia Coli And Expression In Brevibacterium Flavum

Phosphoserine aminotransferase (SerB) is one of key enzymes in biosynthesis of L-serine, and it can katalyzes the reaction of 3-Phosphohydroxypyruvate and glutamate forming phosphoserine and α-Ketoglutarate, which finally involved in biosynthesis of L-serine. In this study the SerB gene was obtained from E.coli Jm109 by PCR and inserted into pEC7 and this recombinant plasmids with SerB gene were transformed into Brevibacterium flavum C-l1 (BfC-11 ) by the method of electrotransformation. By testing the enzyme activity and the yield of L-serine of BfC-11 and BfC-11B, it was showed that the activity of SerB in BfC-11B was higher than that in BfC-11 by 57.06% and the yield of L-serine in BfC-11B was higher than that in BfC-11 by 16.7%. It provides the foundations for developing L-serine high expressed gene-engineering strain.