Compounds and reagents

GP205, sofosbuvir, daclatasvir, and telaprevir were synthesized by GinkgoPharma, China. KK4A peptides (NH₂-KKGSVVIVGRIVLSGK-COOH) were synthesized by GL Biochem (Shanghai) Ltd, China. The MEGAscript T7 High-Yield Transcription Kit was obtained from Ambion (Carlsbad, CA, USA). The HCV protease FRET substrate (RET S1) (sequence: Ac-Asp-Glu-Asp(EDANS)-Glu-Glu-Abu-Ψ-[COO]-Ala-Ser-Lys(DABCYL)-NH₂) was obtained from AnaSpec, Inc (Fremont, CA, USA). The Renilla-Glo™ Luciferase Assay System kit was obtained from Promega (Madison, WI, USA). The cell viability and proliferation assay kit (WST-1) was obtained from Roche Applied Science (Mannheim, Germany). Human plasmin, kallikrein, and alpha-thrombin were obtained from Calbiochem (La Jolla, CA, USA). Human factor Xa was obtained from Abcam (Cambridge, MA, USA). The protease substrates H-[d-Ile]-Phe-Lys-pNA, H-[d-Val]-Leu-Arg-pNA, Boc-Ile-Glu-Gly-Arg-AMC, and Bz-Phe-Val-Arg-pNA and protease inhibitors H-[d-Phe]-Pro-Arg-chloromethyl ketone and D-VLK-CMK were obtained from Bachem (King of Prussia, PA, USA). Leupeptin was obtained from Bachem (King of Prussia, PA, USA). The plasmids pET22b, pET28a, pMD18, and pFKI were obtained from Novagen, Darmstadt, Germany. Liver mircosomes of rats, dogs, and humans; Liver Pool suspended human primary hepatic cells; and testosterone were obtained from the Research Institute for Liver Diseases (Shanghai) Co., Ltd. China.