A structural investigation of the capsular polysaccharide of Klebsiella K69.

The structure of the capsular polysaccharide isolated from Klebsiella serotype K69 has been investigated by a combination of chemical and spectroscopic methods. The repeating structure of the deacetylated polysaccharide is shown to be of the "3 + 1 + 1" type, and it carries a 1-carboxyethylidene acetal at positions 4 and 6 of a terminal galactosyl group. The location of acetyl groups in the polysaccharide has not been established. The repeating unit of the deacetylated polysaccharide has the following structure. (Formula: see text).