Occurrence of pyruvic acid in capsular polysaccharides (K antigens) of klebsiellas

: The capsular polysaccharides of 77 Klebsiella K-types were analysed for the presence of pyruvic acid. One half of the polysaccharides investigated were found to contain between 1.3 and 12% of the keto acid. A comparison between the analyses performed and the calculated values from some pyruvic acid containing polysaccharides of known structure showed that there is only in 5 out of 10 cases a good correlation with a regular substitution of the oligosaccharide repeating units.