Effect of CHAPS and Tween-20 on the measurement of enzymatic activity of dengue virus's NS3

LEILA A. CABABIE; J. JEREMÍAS INCICCO; LEOPOLDO G. GEBHARD; ANDREA V. GAMARNIK; RODOLFO M. GONZÁLEZ-LEBRERO; SERGIO B. KAUFMAN

Sierra de la Ventana, Buenos Aires

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Biofísica; 2014

The dengue virus's NS3 protein is a helicase that catalyzes thehydrolysis of ATP and couples the free energy of this reaction todrive translocation on single strands and unwinding double strandsof RNA. A frequent experimental problem encountered workingwith enzymes is the loss of specific catalytic activity when thismeasurement is performed at low enzyme concentrations.Therefore we examined whether the presence of detergents in thereaction medium during activity measurements is able to overcomethis difficulty. We will present experimental results which show thattwo detergents of different chemical nature such as CHAPS (3 -[(3-Cholamidopropyl) dimethylammonio] -1- propanesulfonate) andTween 20 (Polyoxyethylene (20) sorbitan monolaurate) keep thecatalytic activity constant regardless of the concentration enzymeused.