EIS investigation on human OR 17-40. Nyquist plot for the human OR 17-40 in the absence and in the presence of specific ligands (heptanal and helional molecules). The impedances are normalized to the static value of the native state Zreal(0). In the upper figure, symbols report experiments carried out with a standard three electrode electrolytic cell sketched on the right-hand side part of the figure (with WE, working electrode; CE, counter electrode; RE, reference electrode). Here, crosses refer to the absence of an odorant and empty (full) squares to the presence of an heptanal (helional) odorants at concentration of 10−10M. In the lower part of the figure, lines report theoretical results with the continuous curve referring to the native state configuration with RC = 70 Å and the dashed line referring to the active state configuration with RC = 46 Å .
Reggiani et al. Nanoscale Research Letters 2012 7:340 doi:10.1186/1556-276X-7-340