Skip to main content
. 2018 Oct 9;1(5):e201800148. doi: 10.26508/lsa.201800148

Figure 4. The ErmBL L7 and L7K8 mutants discriminate between closely related antibiotics.

Figure 4.

(A, B) Chemical diagrams for Ery and Ole. (C) Classical toeprinting analysis of translational arrest by wild-type ErmBL (ermBL WT), an L7 single mutant (ermBL L7), and an L7K8 double mutant (ermBL L7K8), in the absence or presence of the antibiotics Ery and Ole. The white arrow indicates ribosomes on the start codon, and the black arrow indicates arrested elongation complexes with the GAU codon encoding Asp-10 in the ribosomal P-site. The sequence of wild-type ErmBL is shown. (D) Disc-diffusion test plates used to assay the ability of nascent ErmBL WT, ErmBL L7, and ErmBL L7K8 to cause translational arrest in vivo in the absence or presence of Ery or Ole soaked into paper discs. It should be noted that the double mutant shows greater antibiotic selectivity in vivo compared with the single mutant, as indicated by the light blue ring observed in the +Ole condition for the ErmBL L7 mutant.