1. Enzymatic activity of a subtilisin homolog, Tk-SP, from Thermococcus kodakarensis in detergents and its ability to degrade the abnormal prion protein.
- Author
-
Hirata A, Hori Y, Koga Y, Okada J, Sakudo A, Ikuta K, Kanaya S, and Takano K
- Subjects
- Archaeal Proteins chemistry, Archaeal Proteins genetics, Edetic Acid chemistry, Escherichia coli metabolism, Hot Temperature, Hydrogen-Ion Concentration, Recombinant Proteins biosynthesis, Recombinant Proteins chemistry, Recombinant Proteins genetics, Subtilisin chemistry, Subtilisin genetics, Archaeal Proteins metabolism, Detergents chemistry, Prions metabolism, Subtilisin metabolism, Thermococcus enzymology
- Abstract
Background: Tk-SP is a member of subtilisin-like serine proteases from a hyperthermophilic archaeon Thermococcus kodakarensis. It has been known that the hyper-stable protease, Tk-SP, could exhibit enzymatic activity even at high temperature and in the presence of chemical denaturants. In this work, the enzymatic activity of Tk-SP was measured in the presence of detergents and EDTA. In addition, we focused to demonstrate that Tk-SP could degrade the abnormal prion protein (PrPSc), a protease-resistant isoform of normal prion protein (PrPC)., Results: Tk-SP was observed to maintain its proteolytic activity with nonionic surfactants and EDTA at 80°C. We optimized the condition in which Tk-SP functions efficiently, and demonstrated that the enzyme is highly stable in the presence of 0.05% (w/v) nonionic surfactants and 0.01% (w/v) EDTA, retaining up to 80% of its activity. Additionally, we also found that Tk-SP can degrade PrPSc to a level undetectable by western-blot analysis., Conclusions: Our results indicate that Tk-SP has a great potential for technological applications, such as thermo-stable detergent additives. In addition, it is also suggested that Tk-SP-containing detergents can be developed to decrease the secondary infection risks of transmissible spongiform encephalopathies (TSE).
- Published
- 2013
- Full Text
- View/download PDF