The complete mature bovine prion protein highly expressed in Escherichia coli: biochemical and structural studies

According to the `protein only' hypothesis, modification of the 3-dimensional fold of the constituent cellular protein, PrP C, into the disease-associated isoform, PrP Sc, is the cause of neurodegenerative diseases in animals and humans. Here we describe the high-level synthesis in Escherichia coli, and purification in the monomeric form, of a histidine-tagged full-length mature PrP (25–249) of bovine brain, termed His-PrP. Based on biochemical and spectroscopic data, His-PrP displays characteristics expected for the PrP C isoform. The reported expression system should allow the production of quantities of bovine PrP C sufficient to permit 3-dimensional structure determinations.