The stability and validity of the final MTX-IK
complex. (A) Root-mean-square deviations (Å) of the α-carbons in the final MTX-IKCa complex from the starting complex during the 10-ns unrestrained MD simulations. (B) The free energy convergence during the 10-ns unrestrained MD simulations, trajectories were sampled every ns along the simulation time. (C) Calculated and experimental effects for 5 single-alanine mutations on the blocking activity of MTX toward the IKCa channel after 10-ns MDS. The calculated results are normalized values of ΔΔGbinding, whereas the experimental results are obtained as k
T ln [IC50(mutant)/IC50(wt)]. (D) An overview of the final model of the MTX-IKCa complex, with the labels of all the experimentally determined residues.