Structures of the glycopeptidolipid antigens of two animal pathogens: Mycobacterium senegalense and Mycobacterium porcinum

The structures of the major glycolipid antigens of two animal pathogens Mycobacterium senegalense and Mycobacterium porcinum were elucidated by a combination of fast-atom bombardment mass spectrometry, nuclear magnetic resonance spectroscopy, chemical analyses and radiolabeling experiments. Five glycoconjugates belonging to the class of C-mycoside glycopeptidolipids were characterized in each species. They shared with those recently described in M. peregrinum the same unusual distribution of the disaccharides on the alaninol end of the molecules. Both species showed the presence of the novel sulfated glycopeptidolipid. In addition, some acetylated forms of the glycolipids were also present in the species examined. Identical seroreactivities were observed between the glycolipid antigens extracted from M. senegalense, M. porcinum and M. peregrinum and an antiserum raised against the whole lipid antigens of M. peregrinum. These data reinforce the close taxonomic relationships between the three mycobacterial species and demonstrate the antigenicity of the new variants of mycobacterial glycopeptidolipids.