<p>(A) NaphSDS-Page analysis of the purification full-length NS3 (NS3FL) from <i>E coli</i>. Lane 1, molecular weight marker; lane 2, 10xHis-NS3FL (10xHis-Ubiquitin site) after refolding by dialysis; lane 3 and 4, NS3FL after 10xHis-Ubiquitin site tag excision by YUH in ratio 1:5 and 1:1, respectively; and lane 5, purified NS3FL protein following His-TRAP column chromatography. The gel was stained with Comassie brilhant blue G. (B) A range of pyran naphthoquinones was tested for their activity against ATPase site. The screening was performed in buffer containing 40 mM Tris-HCl (pH 7.5), 5 mM DTT, 100 mM KCl, and 5 mM MgCl<sub>2</sub>. The compounds were pre-incubated with 600nM NS3FL for 10 min at 30 °C followed by the addition of 1 mM ATP. The screening was carried out in duplicate and the unpaired t-test was used for the statistical analysis. Those compounds showing statistical difference from the control (p < 0.05) were labeled with an asterisk.</p
