The fusion of viruses with cellular membranes is an essential step in the life cycle of enveloped viruses. Here, the authors present cryo-electron microscopy (cryo-EM) structures of a prototype class III fusion protein GP64 in prefusion and early intermediate states, and show that the coordination between multiple histidine residues acts as a pH sensor and activator.
- Jinliang Guo
- Shangrong Li
- Dijun Du
