Gene expression and characterization of 2-keto-3-deoxy-gluconate
kinase, a key enzyme in the modified Entner-Doudoroff pathway of
Serratia marcescens KCTC 2172
We cloned 2-keto-3-deoxy-gluconate kinase (KDGK), which catalyzes the
phosphorylation of 2-keto-3-deoxygluconate (KDG) to
2-keto-3-deoxy-6-phophogluconate (KDPG) from Serratia marcescens KCTC
2172. The nucleotide sequence revealed a single open reading frame
containing 1,208 bp and encoding for 309 amino acids, with a molecular
weight of 33,993 Da. The enzyme was purified via GST affinity
chromatography. The putative KdgT binding site was detected upstream of
the initial codon. The KDG kinase utilized 2-ketogluconate (KG) and KDG
as substrates. The optimal temperature and pH for KDGK activity were
50\ubaC and 8.0, respectively