Figure 4. Lipidome analyses of H. influenzae density gradient purified OMVs and OM.
(a,b) PL (a) and FA (b) compositions of OMV and OM preparations derived from Rd KW20, Rd ΔvacJ, and Rd ΔyrbE were analysed by thin-layer chromatography and by gas liquid chromatography in combination with flame-ionization detection, respectively. Mean percentage values with s.e.m. of total PLs (a) and FAs (b) within a given preparation are shown (n=3 biological replicates). Detected PLs and FAs were: phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine (PS), myristic acid (C14:0), myristoleic acid (C14:1), palmitic acid (C16:0), palmitoleic acid (C16:1), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), and cerotic acid (C26:0). (c,d) Total PE contents (c) and PE species compositions (d) of respective OMV and OM preparations were determined by LC/ESI-MS. Total PE contents (c) are given in x-fold changes normalized to Rd KW20 OMV preparations and PE species compositions (d) are given in percentage of total PE species within a respective preparation. Mean values with s.e.m. are shown (n=3 biological replicates). For PE composition analysis (d), only PE species over 1% (at least in one preparation) are shown. The main FAs of a given PE species are indicated below each species. Additional detected FAs: capric acid (C10:0), lauric acid (C12:0), and lauroleic acid (C12:1). (b,c,d) Significant differences between the data sets are marked by asterisks (P<0.05; one-way ANOVA followed by Sidak's multiple comparison post test).