FIGURE 3.

Structural analysis of lipid Z. A, MALDI-MS analysis of intact carboxymethylated mycolic acids from α-mycolic acids devoid of lipid Z (upper panel) and lipid Z (lower panel). B, EI-MS analysis of in-source pyrolysis fragment generated from a mixture of α-mycolates lacking lipid Z (upper panel) or containing lipid Z (lower panel). C, EI-MS analysis of fragment ions generated from carboxymethylated lipid Z. Cis- and trans-conformation of functional groups were omitted in schematic representations of mycolates for the sake of clarity.