Analysis of the steady state receptor activation in our model for single odorants and mixtures at different concentrations.

(a-b) Illustration for our model of binding of odor molecules to olfactory receptors and the activation process of the receptors for (a) single odorants (b) binary mixtures. (c) The receptor activation, r*, as described by Eq 3. In the limit of small ceff, receptors with the same Keff are activated to the same degree, regardless of the value of . In the limit of large ceff, receptor activation always approaches an asymptotic value depending on , regardless of the value of Keff. Legend format: 1st number: Keff, 2nd number: . (d-e) Examples of the response to binary mixtures as n varies. The activation in response to their constituent components are shown in black lines. In the limit of small ceff, receptor activation for mixtures can be synergistic, hypoadditive or suppressive depending on the values of n. In the other limit, the fraction of activated receptors for mixtures is independent of the value of n and always in between the fraction of activated receptors in response to the constituent components. In (d), component 1: , Keff = 8.33; component 2: , Keff = 20. In (e), component 1: , Keff = 8.33; component 2: , Keff = 20.