The capsular polysaccharides produced by Campylobacter jejuni are known to be important virulence factors and could be important components of vaccines. Determination of their complete structure and function is extremely important. Therefore, in this master thesis, we present a method for the isolation of capsular polysaccharides and their characterization by nuclear magnetic resonance (NMR). For the isolation of capsular polysaccharides, we used the enzyme method and the hot phenol method, with a higher amount of capsular polysaccharides obtained by the latter. Samples were analysed for contaminating proteins and nucleic acids by spectrophotometry, agarose electrophoresis, and SDS-PAGE. We found that capsular polysaccharides obtained by the hot phenol method contained a higher amount of contaminants than capsular polysaccharides obtained by the enzyme method. Silver and periodic acid-Schiff staining were performed to detect capsular polysaccharides and other glycoconjugates. In the phenol samples, we detected lipooligosaccharides and capsular polysaccharides, whereas in the enzyme samples we observed only low molecular weight bands, indicating the presence of lipooligosaccharides. The structure of the polysaccharides was analysed by NMR. In the enzyme samples, we were able to detect and confirm the presence of sugar monomers of capsular polysaccharides of C. jejuni, which are in accordance with the published data. In addition, we observed multiple peaks in anomeric region, suggesting that multiple forms of capsular polysaccharides exists within the sample. Based on our results, we can conclude that we have optimized a novel method to isolate capsular polysaccharides from C. jejuni.
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