Gateway to assembly of face-on trimer configuration.

<p>Calculated elastic interaction energy between two chemoreceptor trimers as a function of trimer orientation (upper axes) and center-to-center trimer distance (lower axes), and (A) membrane thickness and (B) membrane tension. Trimer configurations are rotated from the tip-on to the face-on configuration while maintaining reflection symmetry and a minimum edge-to-edge separation of nm, which yields the face-on trimer configuration at nm (and the tip-on trimer configuration at nm). The vertical lines at nm indicate the face-on trimer separation measured for chemoreceptor lattices <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1003932#pcbi.1003932-Briegel1" target="_blank">[19]</a>, <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1003932#pcbi.1003932-Briegel3" target="_blank">[22]</a>. For ease of comparison, the zero energy for each curve was set at the tip-on configuration. For (A) we set and for (B) we used the monolayer thickness nm corresponding to the <i>E. coli</i> cytoplasmic membrane. All trimer interaction energies were calculated as in <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1003932#pcbi-1003932-g002" target="_blank">Fig. 2</a>.