Computational Study on the Wealth Conformations of Hepatitis C Virus Envelope Glycoprotein 2 and Role of Its Glycan Coat.

Hepatitis C virus (HCV) is a major cause of chronic liver disease and hepatocellular carcinoma. Antibody development efforts mainly revolve around HCV envelope glycoprotein 2 (E2), which mediates host cell entry by interacting with several cell surface receptors, including CD81. We still have limited knowledge about the structural ensembles and the dynamic behavior of both the CD81 binding sites and the glycans on E2. Here, multiple microsecond-long, all-atom molecular dynamics (MD) simulations, as well as a Markov state model (MSM), were performed to provide an atomistic perspective on the dynamic nature of E2 and its glycans. End-to-end accessibility analyses outline a complete overview of the vulnerabilities of the glycan shield of E2, which may be exploited in therapeutic efforts. Additionally, the Markov state model built from the simulation maps four metastable states for AS412 and three metastable states for the front layer in CD81 binding sites, while binding with HEPC3 would induce a conformation selection for both of them. Overall, this work presents hitherto unseen functional and structural insights into E2 and its glycan coat, providing a new theoretical foundation to control the conformational plasticity of E2 that could be harnessed for vaccine development.