Electrochemical study of human olfactory receptor OR 17–40 stimulation by odorants in solution

The human olfactory receptor OR 17–40 co-expressed with α-subunit of Golf protein in yeast was attempted as a bio recognition part of impedimetric biosensor. The receptor in its natural membrane environment was anchored to a gold-coated glass substrate modified with thiol-based multilayer. Step-by-step building-up of the OR 17–40 based biofilm was monitored using surface plasmon resonance technique. Stimulation of the OR 17–40 with its cognate odorant helional in phosphate-buffered saline was probed by means of electrochemical impedance spectroscopy under various conditions. Activation of OR 17–40 in the presence of GTP-γ-S at 4 °C was found to improve the sensitivity of the developed label-free biosensor, probably via the enhancement of the specific biochemical signal.