Oligosaccharide Neisseria meningitidis

Combination of pyrolysis and m.s. has been found to enable rapid analysis of sialic acids and other carbohydrates (for ng quantities of oligosaccharides and polysaccharides). Thus, the presence of (2— 8) and (2—>9) linkages in Neisseria meningitidis capsular polysaccharides has been confirmed.154... 

Fig. 3. Generalised structure of the dephosphorylated Neisseria meningitidis oligosaccharide part of the LPS...

In a study of the tolerability and immunogenicity of Hib vaccines, 30 volunteers aged 69-84 years were immunized with either Pedvax-Hib (a conjugate of Hib polysaccharide and an outer membrane protein complex of Neisseria meningitidis-YR -OMP) or Hib TITER (a conjugate of Hib oligosaccharide and a non-toxic mutant diphtheria toxin, CRM 197-HbOC) (4). The volunteers... 

Figure 4 CE-MS analysis of core oligosaccharides from Neisseria meningitidis strain NGH15. (a) Extracted MS spectrum (b) extracted MS/MS spectrum of ion at m/z 820 ([M + H + NH4] + (c) extracted MS/MS spectrum of ion at m/z 841 ([M + H + NhiJ +i (d) extracted MS/MS spectrum of ion at m/z 870 ([M + H + NH4] +. The experiments were performed using an API 3000 mass spectrometer (Applied Biosystems/Sciex, Concord, Ontario, Canada) via a microspray interface coupiing to a CE system. A sheath solution (isopropanol-methanol, 2 1) was delivered at a flow rate of 1 il min The orifice voitage was set at 30 V. Separations were obtained on approximately 90 cm length of bare fused-silica capillary using 15 mmol 1 ammonium acetate in deionized water at pH 7.0.

FIGURE 7.8 Structure of the conserved inner core oligosaccharide regions of LPS from N. meningitidis and H. influenzae. (A) Haemophilus influenzae capsular and noncapsular strains. (B) Neisseria meningitidis strain. (Adapted from Li, J. et al. Methods Enzymol, 405, 369, 2005. With permission.)... 

Neisseria meningitidis is a pathogen that causes meningitis in humans. It has an unusual capsular homopolysaccharide that is composed of A -acetyl-D-neuraminic acid. The monosaccharide residue has nine carbons (see Fig. 6.20A). It makes up a family of sugar acids called sialic acids that are N- and 0-substituted derivatives (see Chapter 9). The sialic acids are widely distributed and are primarily found at the ends of the oligosaccharide chains attached to glycoproteins that are especially prevalent in bovine and ovine submaxillary mucins, erythrocytes, and nerve tissues. A -acetyl-D-neuraminic acid is biosynthesized by an aldol condensation of pyruvic acid with N-acetyl-D-mannosamine (see Chapter 10). 

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