Supplementary Fig. 10: Blockade currents of chemically modified YR7 peptides.
From: Electrical recognition of the twenty proteinogenic amino acids using an aerolysin nanopore
Histogram of Ib/I0 (top plot of each panel) and scatter plot of blockade duration versus Ib/I0 (bottom plot of each panel) obtained from nanopore experiments during analysis of: (NO2)-YR7 peptide, where the Y amino acid is modified by an additional -(NO2) group (a, n = 5201 events); an equimolar mixture of YR7 and (NO2)-YR7 peptides (b, n = 10615), (SO3H2)-YR7 peptide, where the Y amino acid is modified by an additional -(SO3H2) group (c, n = 3183 events); an equimolar mixture of YR7 and (SO3H2)-YR7 peptides (d, n = 4227 events); (P)-YR7 peptide, where the Y amino acid is modified by an additional -(P) group (e, n = 2626); and a mixture of YR7 (1 M final concentration) and (P)-YR7 (10 M final concentration) peptides (f, n = 10281 events). The chemical modification of the peptide leads to a shift of the mean Ib/I0 value from 0.360 ± 0.002 (YR7) to 0.343 ± 0.002 ((NO2)-YR7), 0.354 ± 0.002 ((SO3H2)-YR7) and 0.355 ± 0.002 ((P)-YR7). The mean value (respectively uncertainty) of relative residual current of each peptide was obtained as the mean value (respectively standard deviation) of a gaussian fit of the corresponding Ib/I0 distribution; from single independent experiments. The data were acquired in 4 M KCl, 25 mM HEPES buffer, at 7.5 pH and 20.0 ± 0.5oC, and under a –50 mV bias applied to the trans compartment.
