Figure 9. Tat/Env binding kinetics and thermodynamics.

(A) Binding kinetics of trimeric wt Env (tw Env), trimeric ΔV2 Env (tΔV2 Env), monomeric wt Env (mwt Env) or monomeric ΔV2 Env (mΔV2 Env) to Tat bound to the Biacore chip. The range of concentrations of Env molecules is indicated. (B) Tat/Env binding thermodynamics by ITC. Tat was titrated with trimeric wt Env. The top panel shows calorimetric data versus time; the lower panel shows integrated areas normalized to the number of moles of Env subunits injected at each injection step.