Figure 11. The β-hairpin in the cytoplasmic region of LmdC is critical for BacA binding.

(A) Predicted structure of LmdC^N, comprising the first 80 amino acids of LmdC. The transmembrane domain is colored light blue. The cytoplasmic domain includes a conserved β-hairpin motif. (B) Clusters of amino acids mutated for the analysis of BacA-LmdC interaction. Mutated amino acids are shown as red sticks. (C) Localization of BacA_Rs-CHY and the indicated LmdC^N_Rs-mNG variants in the ΔlmdC_Rs background. The Pearson’s Correlation Coefficient (PCC) of the two fluorescence signals in a random subpopulation of cells is 0.914 for the wild-type fusion protein (SP119), 0.887 for the R25A-H26A-L27A variant (SP237) and 0.827 for the R30A-S31A variant (SP238). Scale bar: 5 µm. (D,E) Demographs showing the distribution of BacA-mCherry and (D) R25A-H26A-L27A variant (SP237) or R31A-S31A variant (SP238) of LmdC^N-mNG along the outer and inner curve of the cell (n=200 cells per strain). The white line marks the point of transition from the outer and the inner curve. The analysis was performed as described in Figure 10F.