Supporting Information

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Supporting Figure 8
Supporting Figure 9
Supporting Figure 10
Supporting Figure 11
Supporting Text

Fig. 8. Fraction of abortive attempts to methylate in the presence of attractant (Attr) (a) and to demethylate at zero ambient ligand concentration and in the presence of repellent (Rep) (b) for mixed-receptor clusters with and without AN. Statistics were taken from the simulations in Fig. 2a (with AN) and Fig. 2 Inset (without AN).

Fig. 9. Time-averaged histogram of receptor methylation level without (a) and with (b) AN at zero ambient in the presence of attractant (Attr) and repellent (Rep). Statistics were taken from the simulation in Fig. 2b Inset for a and Fig. 2a for b.

Fig. 10. Adaptation error [A([MeAsp]) – A(0)]/A(0) for different-sized clusters where A([MeAsp]) and A(0) are the time-averaged activities at MeAsp concentration [MeAsp] and zero ambient MeAsp, respectively. The mixed cluster of 18 receptors is shown with AN of size 6 (open circles) and without AN (filled circles). Also shown are a single Tar receptor (crosses) and a mixed cluster of 36 receptors without AN (filled squares).

Fig. 11. Adaptation of a mixed cluster of 18 receptors with 12 Tsrs and 6 Tars to step increases of aspartate (solid lines) and serine (dashed lines). Both the cluster activity (a) and average receptor methylation level (b) are shown. The activity curve for aspartate binding is raised vertically by 0.3. Model parameters are given in Model in the main text; for simplicity, the dissociation constants for MeAsp are used for aspartate.