Fig. 3. Strand-displacement kinetics in heterodimeric coiled coils. (A–D) Normalized time-resolved fluorescence decrease upon strand displacement in AxBy peptides. Exemplarily, strand displacements in N-A3B4 by N-Acomp (A), N-A3.5B4 by N-Bcomp (B), C-A3B4 by C-Acomp (C), and C-A3.5B4 by C-Bcomp (D) are shown. Data is fit by a single exponential decay model. (E–H) Least-squares fits of strand displacement in N-A3B4 by A3.5 (E), N-A3.5B4 by B3.5 (F), C-A3B4 by A3.5 (G), and C-A3.5B4 by B3.5 (H) using a competitive binding model in DynaFit53 (forward reaction – black, backward reaction – red). Conditions: 15 μM peptide concentration, PBS (pH 7.4), room temperature, readout: λex = 270 nm, λem = 540 nm. Measurements were performed as triplicates.
