Cloning expression and purification of glycerol dehydrogenase from Klebsiella pneumoniae / 生物工程学报

ABSTRACT

The gldA gene coding glycerol dehydrogenase (GDH) was amplified by PCR with the genomic DNA of Klebsiella pneumoniae as the template. The gldA were inserted in pMD-18T to construct the recombinant cloning vector pMD-gldA. After the DNA sequence was determined, the gldA was subcloned into expression vector pET-32a (+) to construct the recombinant expression vector pET-32gldA. Upon lactose induction, soluble GDH was over-produced by E. coli BL21 (DE3) harboring the expression construct. Recombinant GDH purified by Ni-NTA affinity chromatography showed a single band about 54 kD on SDS-PAGE gel, and the specified activity was about 188 u/mg, the purification fold is 3 times and the activity recovery is 67.5%.