Conformational modifications of gB from Herpes simplex virus type 1 analyzed by synthetic peptides

Entry of enveloped viruses requires fusion of viral and cellular membranes, driven by conformational changes of viral glycoproteins. The crystallized trimeric glycoprotein gB of Herpes simplex virus has been described as a post fusion conformation and several studies prove that like other Class III fusion proteins, gB undergoes a pH dependent switch between the pre- and post-fusion conformations. Using several biophysical techniques, we show that peptides corresponding to the long helix of gB post-fusion structure interfere with the membrane fusion event, likely hampering the conformational rearrangements from the pre- to the post-fusion structures. Those peptides represent good candidates for further design of peptidomimetic antagonists capable of blocking the fusion process.