FIG. 4.
ES-MS and GLC-MS profiles of the alditol acetate derivatives of C. jejuni 81-176 lgtF core OS. (A) ES-MS analysis showing ions at m/z 728.19 and 746.2 (728.2 + H2O) corresponding to a molecule containing two ld-Hep units, one Kdo residue, and one PEA moiety. MS/MS analysis of m/z 728.19 yielded ions at m/z 536.2 (728.19-192) for PEA→ld-Hep→Kdo and at m/z 316.15 (728-412) for PEA→ld-Hep. (B) GLC-MS analysis of the alditol acetate derivatives showing the presence of only ld-Hep. No Glc, Gal, or GalNAc was detected.