Helicases pp 223-233 | Cite as

A Method to Simultaneously Monitor Hepatitis C Virus NS3 Helicase and Protease Activities

  • David N Frick
  • Olya Ginzburg
  • Angela M.I Lam
Part of the Methods in Molecular Biology book series (MIMB, volume 587)


The hepatitis C virus NS3 protein contains an N-terminal serine protease and a C-terminal helicase that unwinds RNA or DNA duplexes. The HCV NS3 protein is the target for several antiviral drugs in clinical trials, which inhibit the protease function. A method is reported to simultaneously monitor the helicase and protease function of the NS3 protein in a single reaction using fluorescence spectroscopy and a single chain recombinant protein where NS3 is fused to its protease activator NS4A. The method monitors both activities together in real time and is amenable to high-throughput screening. This new procedure could be used to identify compounds that inhibit both the helicase and protease activity of NS3.

Key words

Helicase protease ATPase high-throughput screening antiviral agents 


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • David N Frick
    • 1
  • Olya Ginzburg
    • 1
  • Angela M.I Lam
    • 1
  1. 1.Department of Biochemistry & Molecular BiologyNew York Medical CollegeValhallaUSA

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