Fig. 2: Binding sites for PE and lipid A with functional validation.
From: Mechanistic basis of antimicrobial resistance mediated by the phosphoethanolamine transferase MCR-1
a On the left, a zoomed in panel depicting the PE binding site within the MCR-1 structure, in cartoon representation and colored light gray. PE is shown and colored as in Fig. 1d, and side chains of conserved residues in close proximity to the ligand are shown as sticks and colored in accordance with the structure. On the right, a zoomed in panel depicting the KLA binding site between the BH and PH3/4. KLA is shown and colored as in Fig. 1d, and side chains of nearby residues are shown as sticks. Nitrogen, oxygen, and phosphorus atoms are colored as in Fig. 1d. b TLC plate showing the migration of lipid A isolated from W3110 (ΔlpxT, ΔeptA) cells grown in LB broth and transformed with MCR-1 WT, empty pWSK29 plasmid, and the indicated MCR-1 mutants. Double mutants with R190A are denoted by blue labeling. Protein expression was induced with 10 μM IPTG. Major 32P-labeled lipid A species are indicated with an arrow and labeled to the left. The data represent three biological replicates. c Efficiency-of-plating assay depicting 10-fold dilutions of cells expressing MCR-1 WT, mutants, or neither, labeled to the left, in the presence of 0, 0.4, and 1.5 μg/mL PMB.
