Dual Allosteric Inhibitors Jointly Modulate Protein Structure and Dynamics in the Hepatitis C Virus Polymerase

Area of Science:

• Virology
• Molecular Biology
• Drug Discovery

Background:

• Hepatitis C virus (HCV) infection affects nearly 200 million people globally.
• The HCV polymerase (NS5B) is a key viral target for developing effective therapies.
• Non-nucleoside inhibitors (NNIs) targeting NS5B have been identified, but their combined mechanisms are unclear.

Purpose of the Study:

• To elucidate the molecular mechanisms behind the enhanced inhibition of NS5B by dual NNIs.
• To investigate the compatibility of simultaneous binding of two NNIs at nonoverlapping sites.
• To identify novel enzyme conformations and dynamics induced by dual NNI binding.

Main Methods:

• Utilizing molecular dynamics simulations.
• Analyzing enzyme conformations and dynamics under dual NNI inhibition.
• Comparing inhibition by individual NNIs versus dual NNIs.

Main Results:

• Nonoverlapping binding sites for two NNIs are compatible with simultaneous NS5B inhibition.
• Dual NNIs induce novel, synergistic enzyme conformations and dynamics.
• Specific molecular mechanisms underlying enhanced NS5B inhibition were identified.

Conclusions:

• Dual NNIs can act in concert to enhance NS5B inhibition through induced conformational changes.
• Understanding these mechanisms can optimize NNI combinations for more effective HCV therapeutics.
• This approach may help overcome viral resistance, a major challenge in HCV treatment.