Fig. 5
Discrimination of endothelin 1 and 2 with WtFraC at pH 4.5. a Molecular surface representation of endothelin 1 (PDB: 1EDN) and endothelin 2 (homology model from endothelin 1, PyMOL) using electrostatic coloring (PyMOL). b Above: amino-acid sequences of endothelin 1 and 2. Blue lines indicate the disulfide bridges in each polypeptide. Below: I res% and dwell time for endothelin 1 and endothelin 2 blockades at −50 mV in pH 4.5 buffer (1 M KCl, 0.1 M citric acid, 180 mM Tris base). Standard deviations are calculated from three experiments (Supplementary Fig. 16). c Representative endothelin 1 and endothelin 2 blockades to the same FraC nanopore under −50 mV applied potential. d Histogram (left) of residual currents provoked by 2 µM endothelin 1 and corresponding heatplot depicting the standard deviation of the current amplitude vs. I res% (right). e Same as in d but after addition of 8 µM endothelin 2 to the same pore revealing a second population. Graphs were created with custom R scripts. All recordings were conducted with 50 kHz sampling rate and 10 kHz Bessel low-pass filter
