CHEMICAL AND SPECTROSCOPIC CHARACTERIZATION OF THE PHOSPHATIDYLINOSITOL MANNO-OLIGOSACCHARIDES FROM MYCOBACTERIUM-BOVIS AN5 AND WAG201 AND MYCOBACTERIUM-SMEGMATIS MC(2)-155

Two classes of phosphatidylinositol manno-oligosaccharides (PIMs) were isolated from each of Mycobacterium bovis AN5 and WAg201 and Mycobact erium smegmatis mc(2) 155. The deacylated PIMs (dPIMs), were identifie d as hexasaccharide (dPIM-6) and disaccharide (dPIM-2) species compose d of mannose, myo-inositol, glycerol and phosphate residues in the pro portions of 6:1:1:1 and 2:1:1:1, respectively. Structural analysis, em ploying a combination of microanalytical methods, nuclear magnetic res onance spectroscopy, and mass spectrometric techniques established tha t the sequence of residues within dPIM-6, as shown below, was identica l in the three mycobacterial strains investigated. [GRAPHICS] Enzymic degradation of dPIM-6 with an alpha-(1-2)-D-mannosidase resulted in th e formation of a tetrasaccharide (dPIM-4) whose structure, along with that of dPIM-2, were identified as truncated versions of dPIM-6. The H -1 and C-13 NMR resonances of both native dPIM species and the dPIM-6 degradation product were fully assigned by homo- and hetero-nuclear ch emical shift correlation methods, and the location of the phosphodiest er group was determined by a 2D H-1-P-31 chemical shift correlation ex periment. (C) 1998 Elsevier Science Ltd. All rights reserved.