Persister control by leveraging dormancy associated reduction of antibiotic efflux
Fig 5
Viability of E. coli HM22 after treatment with rifamycin SV and eravacycline.
(A) Effects of 100 μg/mL rifamycin SV on the viability of normal (black bars) and persister (patterned bars) cells of E. coli HM22. Means ± SE are shown (n = 3). (B) Intracellular concentration of rifamycin SV based on the reporter bioassay. Rifamycin SV concentration was calculated using the standard curve of reporter strain for each population (S2B Fig). Means ± SE are shown (n = 3). (C) Effects of eravacycline on the viability of normal (black bars) and persister (patterned bars) cells of E. coli HM22. Means ± SE are shown (n = 3). (D) Intracellular concentration of eravacycline based on the reporter bioassay. Eravacycline concentration was calculated using a standard curve of reporter strain for each population (S2C Fig). Means ± SE are shown (n = 3). (E) Binding pocket of minocycline (top) and eravacycline (bottom) in the 30S ribosomal unit. Minocycline interacts with G966, C1195, U1196, G1197, and G1198 via hydrogen bonding and ionic interactions (black dashed lines) mediated by a pair of Mg ions. Eravacycline occupies the same binding pocket as minocycline but also binds to additional residues—C1054, C1195, and U1196. (c) Color scheme: uracil (teal), cytosine (light blue), guanine (gold), adenine (purple), C (green stick); O(red, stick); N (blue); F (cyan, stick); Mg ion (magenta, sphere). Solvent is omitted for clarity. (F) Different antibiotic treatments of E. coli HM22 persister cells including 100 μg/mL of ampicillin, 100 μg/mL of eravacycline, and the combination of both. Means ± SE are shown (n = 3). (G-H) Relative number of viable E. coli HM22 persister cells after eravacycline treatment (initial number normalized as 100%). The changes in OD600 (G) and CFU (H) were followed over time. Means ± SE are shown (n = 3 for OD600 and n = 4 for CFU). * p-value≤ 0.05, ** p-value ≤ 0.01, *** p-value ≤ 0.001, ****p-value ≤ 0.0001.