Cloning and expression of the genes encoding glycerol dehydratase reactivase and identification of its biological activity

The gdrA and gdrB genes encoding glycerol dehydratase reactivase were amplified using the genomic DNA of Klebsiella pneumoniae as the template. The gdrA and gdrB genes were inserted into pMD-18T to yield the recombinant cloning vector pMD-gdrAB. After the DNA sequence was determined, the gdrAB gene was subcloned into expression vector pET-28a(+) to yield the recombinant expression vector pET-28gdrAB. Under screening pressure by ampicillin and kanamycin simultaneously, the activity of glycerol dehydratase reactivase was characterized by the coexpression of pET-32gldABC, which carried the gldABC gene encoding glycerol dehydratase, and pET-28gdrAB in E. coli BL21 (DE3).