STRUCTURAL CHARACTERIZATION OF VIRAL FUSION PROTEINS

Infection by enveloped viruses is initiated by the fusion oi viral and cellular membranes. In many cases, the viral membrane proteins that m ediate fusion must undergo conformational changes to become active. In fluenza hemagglutinin, for example, is activated by a dramatic conform ational rearrangement, triggered by the low pH of the intracellular co mpartment in which fusion occurs. Structural characterization of this rearrangement has led to a reconsideration of how hemagglutinin mediat es membrane fusion.