Fig. 4: BAK 15–186 1H,15N-HSQC perturbation indicates Eltrombopag binds to the α4/α6/α7 groove.
From: Eltrombopag directly activates BAK and induces apoptosis
a 1H,15N-HSQC spectra of 0.2 mM 15N-labeled BAK 15–186 were recorded in the presence of DMSO (control, red) or 4.0 mM Eltro (green) shown in different colors. Peaks on the right indicate the perturbations at selected residues. b Chemical shift perturbations (CSPs) were plotted as a function for BAK residues, when 1H,15N-HSQC spectra of BAK 15–186 were recorded after titration of Eltro at the ratio of protein:Eltro=1:20. CSPs per BAK residue were calculated using the formula CSPs = [(∆δNH2 + (∆δN/25)2)/2]1/2. The threshold value was defined as average CSP value plus 1/2 standard deviation. c, d Surface and cartoon mixed model (c) or surface model (d) of BAK (PDB:2IMS) showing residues (indicated in blue) that have obvious chemical shift changes or disappearance of signals (peak intensities decreased to the level of noise) in the 1H,15N-HSQC spectra after the perturbation by Eltro.
