ABSTRACT
The gene of beta-glucuronidase from Thermotoga maritima was cloned into the plasmid pHsh, and expressed in Escherichia coli JM109. The recombinant protein was purified to homogeneity by a simple step, heat treatment. The recombinant enzyme had a molecular mass of 65.9 kD. The optimal activity of beta-glucuronidase was found at pH 5.0 and 80 degrees C. The purified enzyme was stable over a pH range from 5.8 to 8.2 and had a half life of 2 h at 80 degrees C. The kinetic experiments at 80 degrees C with p-nitrophenyl-beta- glucuronide as substrate gave a K(m) and V(max) of 0.18 mmol/L and 312 u per mg of protein. The purified enzyme could transform glycyrrhizin to glycyrrhetinic acid.
Subject(s)
Cloning, Molecular , Enzyme Stability , Escherichia coli , Genetics , Glucuronidase , Genetics , Metabolism , Glycyrrhetinic Acid , Metabolism , Glycyrrhizic Acid , Metabolism , Hot Temperature , Kinetics , Recombinant Proteins , Genetics , Metabolism , Thermotoga maritima , GeneticsABSTRACT
Hemicellulose is a kind of very abundant carbohydrate,which is not y ot exploited Arabinofuranosidase is important enzyme in biodegradation of hemi cellulose Up to now many arabinofuranosidases and genes have been studied in t he world In this paper, we reviewed mainly on the classification, characterizati on, utility and gene expression of arabinofuranosidase