Objective: To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope.
Methods: A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity chromatograph. After being labelled with biotin, HaPrP was mixed with PrPSc preparation from scrapie strain 263K.
Results: Protease-resistant bands were detected after four-day incubation.
Conclusion: The new conversion model provides a reliable, easily handling, and environment-friendly method for studies of prion and transmissible spongiform encephalopathies.