Figure 6
From: Modification of the loops in the ligand-binding site turns avidin into a steroid-binding protein
Analysis of sbAvd protein-testosterone interaction by MRFS method (A) A schematic representation of the experimental assembly used in the analyses. Testosterone was tethered to the AFM tip using a flexible PEG crosslinker. The steroid-binders sbAvd-1 and sbAvd-2 were covalently bound to the mica surface via a short homobifunctional spacer. (B) The force-distance cycle of the sbAvd-1 - testosterone interaction showing an unbinding event. The typical non-linear shape of the event results from the elastic properties of the PEG linker. (C) The force-distance cycle showing a sbAvd-2 - testosterone bond dissociation. Insets in (B) and (C) represent force-distance cycles in which the protein-testosterone interaction is inhibited with free testosterone.