background: parathyroid hormone (pth) secreted by parathyroid glands regulates the metabolism of calcium and phosphorus in bone and kidney. thereby, it can stimulate bone formation, and is a promising agent in the treatment of osteoporosis. mature form of pth consists of 84 amino acids; however, the first 34 residues of pth cover the majority of hormonal action. methods: in this study, the fusi...

BACKGROUND Prostase/KLK4 is a member of the human kallikrein (KLK) gene family that is expressed in prostate epithelial cells under the regulation of androgenic hormones. In this study, we sought to characterize the substrate specificity of KLK4 in order to gain insight into potential physiological roles of the enzyme. METHODS A chimeric form of KLK4 was constructed in which the pro-region of...

Analytical gel filtration A Superdex 75 column driven by an AKTA FPLC system (GE Healthcare) was used to separate monomeric and dimeric Venus-GRX2 immediately prior to spectral measurements and to evaluate the extent to which Venus-Gcn4 had been converted to monomer by enterokinase. All gel filtration experiments involving these proteins were performed using columns that had been equilibrated i...

BACKGROUND Recombinant proteins fused with specific cleavage sequences are widely used as substrate for quantitatively analyzing the activity of proteases. Here we propose a new fusion platform for multiple proteases, by using diaminopropionate ammonia-lyase (DAL) as the fusion protein. It was based on the finding that a fused His6-tag could significantly decreases the activities of DAL from E....

The VacA toxin secreted by Helicobacter pylori is considered to be an important virulence factor in the pathogenesis of peptic ulcer disease and gastric cancer. VacA monomers self-assemble into water-soluble oligomeric structures and can form anion-selective membrane channels. The goal of this study was to characterize VacA-VacA interactions that may mediate assembly of VacA monomers into highe...