Purification of Capsular Polysaccharide Complex from Gram-Negative Bacteria

  • Carlos A. Alvarez
  • Brian A. CobbEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1954)


Capsular polysaccharides are a dominant class of antigens from bacteria, both pathogenic and symbiotic or commensal. With the rise of awareness for the influence of the microbiota over immune system development and immune homeostasis, analysis of the antigens is more important than ever. Here we describe a method for the isolation of capsular polysaccharide from gram-negative bacteria, with the purification of polysaccharide from the commensal bacterium Bacteroides fragilis serving as an example. The method efficiently removes all detectable endotoxins and other lipid components, proteins, and nucleic acids, providing a source of capsular polysaccharide for immunologic study.

Key words

Capsule Polysaccharide Bacteria Purification Carbohydrate Glycan Extraction Endotoxin 



This work was supported by NIH grants GM115234 and GM082916 to BAC, and AI089474 to CAA.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Case Western Reserve University School of MedicineClevelandUSA

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