Streptococcus pneumoniae type 14 polysaccharide

The type-specific capsular polysaccharide from Streptococcus pneumoniae type 5 contains 2-acetamido-2,6-dideoxy- -D-x>>/o-hexopyranosyl-4-ulose residues (17). Sugar nucleotides of hexos-4-uloses are important intermediates in the transformation of sugars during the biosynthesis, but this is the only known example of such a sugar as a polysaccharide component. 

The pyruvic acid may also be linked to vicinal positions. When linked to 0-3 and 0-4 of a D-galactopyranosyl residue (40), the dioxolane ring becomes cw-fused. In the limited number of known examples, the absolute configuration at the acetalic carbon atom is (S), as in 40. There are some examples of tra -fused dioxolane rings, and these are more sensitive to hydrolysis with acid than the others. Thus, pyruvic acid is acetalically linked to 0-3 and 0-4 of an a-L-rhamnopyranosyl residue in the Klebsiella type 72 capsular polysaccharide, to 0-2 and 0-3 of an a-D-galactopyranosyl residue in the Streptococcus pneumoniae type 4 capsular polysaccharide, and to 0-2 and 0-3 of a S-D-glucopyranosyluronic acid residue in the Klebsiella K1 capsular polysaccharide. " In the extracellular polysaccharide from... 

T. Sugawara and K. Igarashi, Synthesis of a trisaccharide component of the capsular polysaccharide of Streptococcus pneumoniae Type 19F, Carbohydr. Res. 772 195 (1988). 

K. Leontein, B. Lindberg, J. Lonngren, and D. J. Carlo, Structural studies of the capsular polysaccharide from Streptococcus pneumoniae Type 12 A, Carbohydr. Res., 114 (1983) 257-266. 

Benaissa-Trouw B, Lefeber DJ, Kamerling JP, Vliegenthart JF, Kraaijeveld K, Snippe H. Synthetic polysaccharide type 3-related di-, tri-, and tetrasaccharide-CRM(197) conjugates induce protection against Streptococcus pneumoniae type 3 in mice. Infect Immun. 2001 69 4698-4701. 

As a first attempt to synthesise uronic acid-containing structures from this polysaccharide and from the polysaccharide of Streptococcus pneumoniae type 3 (Fig. 6) [67], the common Koenigs-Knorr type donor methyl (2,3,4-tri-O-acetyl-a-D-glucopyranosyl bromidejuronate (easily obtained from the 3,6-glucurono-lactone and recrystallised from ethanol [68]) was tried in coupling reactions with the relevant acceptors 44 and 45 (for structures see Scheme 14, p. 189) and... 

The synthesis of the Streptococcus pneumoniae type 14 polysaccharide is shown in Scheme 4.46 [505]. As illustrated, condensation of the lactosaminyl bromide 225 with the lactose... 

SCHEME 4.46 Synthesis of Streptococcus pneumoniae type 14 polysaccharide using cyanoethylidene derivative. 

A. Sundgren, M. Lahmann, and S. Oscarson, Block synthesis of Streptococcus pneumoniae type 14 capsular polysaccharide structures, J. Carbohydr. Chem., 24 (2005) 379-391. 

Some glycosidic linkages have proved stable to hydrogen fluoride solvolysis. Attempts to isolate monosaccharides by solvolysis of the O-specific polysaccharide (13) of Shigella sonnet phase 1 with hydrogen fluoride and of the capsular polysaccharide (14) of Streptococcus pneumoniae type 1 failed. Prior acetylation of the free amino groups of the diamino sugar did not render the polymer susceptible to the solvolysis. 

Figure 2. Comparison of NMR spectra recorded at 500 MHz for three high molecular weight bacterial polysaccharides. A) Cell wall polysaccharide from Streptococcus mitis J22 at 23° C. B) Capsular polysaccharide of Vibrio cholerae 0139 at 60° C. C) Capsular polysaccharide from Streptococcus pneumoniae type 1 at 50 ° C. ...

Ido UA-(l -> 4)-2,5-anhydro-D-Cl- Hlmannltol has been synthesized. Conventional synthetic methods have been used to obtain the deslalylated human Cad-antigenic determinant O -p-D-GalpNAc-d - 4)-0-6-D-Gal -(l - 3)-D-Gal2NAc,the synthetic precursor (4) of this compound and the trisaccharide unit of the capsular polysaccharide of Streptococcus pneumoniae Type 4, -B-D-Man NAc-C 1 - 3)- -a-L-Fuc NAc-(1 -> 3)-D-GalNAc. 

CjHisOgP 232.127 Present in the repeating unit of the capsular polysaccharide of Streptococcus pneumoniae type 17F. 

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