Electron spin resonance spin-label studies of mouse olfactory epithelium.

Three classes of interaction of spin-labeled odors with olfactory membrane of mouse were identified by electron spin resonance spectroscopy and correlated with the olfactory potencies of those odors. Also, variation of fluidity in this membrane was probed using spin-labeled lipids in which the nitroxide group was at increasing distances from the lipid headgroup. A cooperative model of olfactory transduction in agreement with the results is introduced, and typical dose response curves are computed that can predict molecular features necessary for a strong odor.