Role of electrostatic interactions in the binding process.

Binding rate (A) and capture rate (B) for PUMA interacting with Mcl-1 at different ionic strengths depend upon ionic strength, whereas complex evolution rate (C) and relative success probability that proceed to bound complex (D) display little or no dependence upon ionic strength. Bind rate, capture rate, and evolution rate are obtained by calculating the reciprocals of FPTon, MPTcap and FPTevo. All the units of rates are s−1. Red data points represent results from simulations performed with no charges included. Successful collision rate is calculated by mean value of each quotient of bind rate and capture rate. Relative success probability is the ratio of successful collision rate with successful collision observed without electrostatic interactions. Lines to guide the eye.