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A High-Throughput Luciferase Assay to Evaluate Proteolysis of the Single-Turnover Protease PCSK9
Published on: August 28, 2018
HTLV-I protease cleavage of P19/24 substrates is not dependent on NaCl concentration
Julie J Ha1, David A Gaul, Victoria L Mariani
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400, USA.
Abstract:
Understanding the factors that affect the activity of Human T-cell Leukemia Virus type I (HTLV-I) protease is essential for the discovery of inhibitors to be used for the treatment of HTLV-I infection, but little has been reported on the protease to date. Here we report the production of HTLV-I protease in purified yields greater than 150 mg/L, determination of its extinction coefficient, and determination of the optimum conditions for cleavage of the p19/24 substrates (DABCYL)-(GABA)-PQVL-Nph-VMH-(EDANS), (DABSYL)-(GABA)-PQVL-Nph-VMH-(EDANS), and (DABSYL)-(GABA)-PQVLPVMH-(EDANS). The highest activity was found at pH 5.2-5.3 and 37 degrees C. There was no effect on activity upon change in sodium chloride concentration from 0 to 1500 mM. The values of K(m) and k(cat) for cleavage of these substrates by the protease with and without the histidine tag were determined.
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