FIG. 7.

Schematic of the kinetic and mechanical parameters describing early fusion dynamics of HIV-1. Mean adhesion force (f), dissociation rate (k₀), change in free energy (ΔG^‡), and distance from the free energy minimum (x^‡) of the bonds involved in early HIV-1 fusion dynamics. The values above and below the arrows compare the mean adhesion forces and dissociation rates of the bonds corresponding to the binding and conformational states linked by the arrows. The initial binding of CD4 to gp120, the conformation change of gp120, and finally gp120 binding to CCR5 are illustrated here above their corresponding energy potentials. Data were collected with a retraction velocity of 10 μm/s.