Abnormal prions are infectious agents involved in a neuro-degenerative disease, which occurs naturally such as Chronic Wasting Disease (CWD) in deer and elk, Bovine Spongiform Encephalopathy (BSE) in cattle, Scrapie in sheep and goats and Creutzfeldt-Jakob Disease (CJD) in humans. The cellular prion protein of the elk consists of 233 amino acids (residues 25-257), which represents an autonomous folding unit with three α-helices and two-stranded anti-parallel β-sheets. Here, we demonstrated elk-recPrP (Elk recombinant prion protein) which can be obtained as follows; (1) Cloning of elk PrP gene, (2) Expression of a histidine-tagged full-length elk PrP by induction with IPTG in E. coli and (3) Purification by affinity chromatography using Ni-NTA agarose resin. In Western blot and ELISA analysis, elk-recPrP showed specific activity against anti-PrP monoclonal antibody. Thus, our elk-recPrP would be a useful tool for the understanding of basic structure and mechanism studies of PrPSC formation.

  The main objective of this study is to find out the shortest path of the vehicle routing problem with time window constraints by using both genetic algorithm and heuristic. Hard time constraints were considered to the vehicle routing problem in this sug