Send to

Choose Destination
Carbohydr Res. 2014 Jan 13;383:97-104. doi: 10.1016/j.carres.2013.11.006. Epub 2013 Nov 19.

Structure elucidation of capsular polysaccharides from Streptococcus pneumoniae serotype 33C, 33D, and revised structure of serotype 33B.

Author information

Pfizer Vaccine Research, 401 N. Middletown Road, Pearl River, NY 10965, USA. Electronic address:
Institute for Biological Sciences, National Research Council, 100 Sussex Dr., Ottawa, ON K1A 0R6, Canada.
Pfizer Vaccine Research, 401 N. Middletown Road, Pearl River, NY 10965, USA.


We report herein the previously unknown structures of the pneumococcal capsular polysaccharides serotype 33C and 33D, and a revised structure of serotype 33B. The syntenic pair 33B/33D has nearly identical polysaccharide repeat units with the exception of one sugar residue (→2-α-Glcp in 33B and →2-α-Galp in 33D). Serotype 33C is structurally more similar to 33B/33D than 33A/33F, in that it also possesses a backbone ribitol-phosphate group and a →3-β-GalpNAc residue, both of which are absent in the repeat units of 33A/33F. Serotype 33C is notably different from all other serogroup 33 polysaccharides, as there is no →3-β-Glcp residue and the location of the O-acetylation of the →5-β-Galf residue (O-6) differs from the other serogroup 33 polysaccharides (O-2). This completes the structural assignments of polysaccharides within serogroup 33 and provides a framework for understanding the recognition of epitopes by serogroup 33 typing sera based on observed cross-reactivities reported in the literature.


Capsular polysaccharide structure; Serogroup 33; Serotype 33B; Serotype 33C; Serotype 33D; Streptococcus pneumoniae

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center