The document presents research on using a thermostable serine protease from the archaeon Thermococcus kodakarensis to digest abnormal prion protein (PrPSc). The protease, called Tk-subtilisin, is stable in high temperatures, denaturants, and surfactants. Western blot analysis showed that Tk-subtilisin can fully digest PrPSc at 100°C in 3% SDS or industrial surfactants, indicating its potential for decontaminating prion-infected materials. Tk-subtilisin offers advantages over other proteases for prion inactivation due to its thermostability in harsh conditions.