(a) Lipidomic results for S. aureus JE2 and JE2-derived daptomycin-resistant (Dap2), dalbavancin-resistant (Dal2) and vancomycin-resistant (Van4) strains. Major species of PGs, DGDGs, LysylPGs, CLs and FFAs from HILIC-IM-MS analysis are shown. Results are row-centred and scaled by unit variance scaling. Statistical significance was determined by Student’s t-test, two-tailed with equal variance, relative to the parent strain (Par). *P ≤ 0.05 and **P ≤ 0.005. (b) Pearson correlation coefficients, r, for the relationship between levels of individual lipid species and MICs of various β-lactam and peptide-based antibiotics for JE2 and JE2-derived strains (n = 4). *P ≤ 0.05, two-tailed, relative to Par. This figure appears in colour in the online version of JAC and in black and white in the print version of JAC.