Fig 4. Analysis of E. cloacae lipid A after meropenem treatment.
(A) MALDI-TOF MS analysis of lipid A extracted from wild-type or ΔphoPQ E. cloacae strains. L-Ara4N modifications are illustrated in red, while C16:0 additions are green. Numbered labels that are both red and green contain both modifications. Each experiment was independently replicated three times, and one representative data set was reported. (B) Predicted lipid A chemical structures in wild type and ΔphoPQ E. cloacae. (C) 32P-radiolabelled lipid A was extracted from treated or untreated wild-type or ΔphoPQ E. cloacae. Lipids were separated based on hydrophobicity using thin-layer chromatography. Red circle denotes L-Ara4N modification, while the green line indicates C16:0 addition.