A new interpretation of the structure of the mycolyl-arabinogalactam complex of Mycobacterium tuberculosis as revealed through characterization of oligoglycosylalditol fragments by fast-atom bombardment mass spectroscopy and 1H nuclear resonance spectroscopy

The cell wall structural polysaccharide of Mycobacterium tuberculosis consists perfect homogalactan and homoarabinan segments and two macro structural units, one within the arabinan and the other in galactan. The extended nonreducing ends of the arabinan contain trisaarabinoside. Depending on the glycosyl composition and glycosyl linkage, the arabinogalactam polymer contains about 100 sugar residues, 60 tp 70 are Ara and 30 to 40 are Gla. The arabinan segments are situated near to peptidoglycan and cytoplasmic membrane.