Purification and characterization of recombinant glucose dehydrogenase isolated from a hyperthermophilic <i>Sulfolobus</i>-like bacterium

Abstract

This study aimed to clone and characterize a thermal resistant glucose dehydrogenase (GDH) and investigate its clinical potential. A Sulfolobus-like thermophilic microbe was first isolated from a hot spring in Taitung, Chihpen County, Taiwan. The gene encoding GDH was cloned from the bacterium and expressed in Escherichia coli. The molecular weight of the enzyme was found to be approximately 39,000 kDa. The enzyme is stable over pH 4.0 to 11.0 and has an optimum pH of 8.0. The thermostability range of the enzyme correlated well with that of the natural environment for Sulfolobus. The GDH showed high substrate specificity for glucose. GDH could be useful in biotechnological applications because of its higher thermostability and substrate specificity when compared with that of other glucose-degrading enzymes.

Keywords: Glucose dehydrogenase, sequencing, glucose test strip, blood glucose meter, diabetes mellitus