Streptococcus pneumoniae Capsular Polysaccharide - PubMed (original) (raw)

Review

Streptococcus pneumoniae Capsular Polysaccharide

James C Paton et al. Microbiol Spectr. 2019 Mar.

Abstract

The polysaccharide capsule of Streptococcus pneumoniae is the dominant surface structure of the organism and plays a critical role in virulence, principally by interfering with host opsonophagocytic clearance mechanisms. The capsule is the target of current pneumococcal vaccines, but there are 98 currently recognised polysaccharide serotypes and protection is strictly serotype-specific. Widespread use of these vaccines is driving changes in serotype prevalence in both carriage and disease. This chapter summarises current knowledge on the role of the capsule and its regulation in pathogenesis, the mechanisms of capsule synthesis, the genetic basis for serotype differences, and provides insights into how so many structurally distinct capsular serotypes have evolved. Such knowledge will inform ongoing refinement of pneumococcal vaccination strategies.

PubMed Disclaimer

Figures

FIGURE 1

FIGURE 1

Comparison of the CPS biological repeat unit structures of S. pneumoniae serotypes 6A, 6B, 14, 15B, 15C 19F, 19A, 19B, and 19C. These are based on published chemical repeat unit structures (9), adjusting for the fact that Glc is the first sugar of the biological repeat unit.

FIGURE 2

FIGURE 2

Organization of the cps loci from selected S. pneumoniae serotypes. Gene and locus designations are as published. Open reading frames (ORFs) within the DNA sequence are indicated by large boxed arrows. Highly conserved ORFs, or those encoding proteins belonging to a particular functional group, are identified as shown in the legend at the bottom of the figure. Assignment of an ORF to a given function-related group is based on the published information for each locus as well as on additional database comparisons for some of the ORFs. The short boxed arrows represent cryptic ORFs not required for CPS biosynthesis in the respective serotype.

Similar articles

Cited by

References

    1. Austrian R. 1981. Pneumococcus: the first one hundred years. Rev Infect Dis 3:183–189 10.1093/clinids/3.2.183. [PubMed] - DOI - PubMed
    1. Austrian R. 1981. Some observations on the pneumococcus and on the current status of pneumococcal disease and its prevention. Rev Infect Dis 3(Suppl):S1–S17 10.1093/clinids/3.Supplement_1.S1. - DOI - PubMed
    1. Dochez AR, Avery OT. 1917. The elaboration of specific soluble substance by pneumococcus during growth. J Exp Med 26:477–493 10.1084/jem.26.4.477. - DOI - PMC - PubMed
    1. Avery OT, Heidelberger M. 1925. Immunological relationships of cell constituents of pneumococcus. J Exp Med 42:367–376 10.1084/jem.42.3.367. [PubMed] - DOI - PMC - PubMed
    1. Avery OT, Morgan HJ. 1925. Immunological reactions of the isolated carbohydrate and protein of pneumococcus. J Exp Med 42:347–353 10.1084/jem.42.3.347. - DOI - PMC - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources