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

The human olfactory receptor OR 17-40 co-expressed with alpha-subunit of G(olf) 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-gamma-S at 4 degrees C was found to improve the sensitivity of the developed label-free biosensor, probably via the enhancement of the specific biochemical signal. (c) 2008 Elsevier B.V. All fights reserved.