Structure of the capsular polysaccharide of Klebsiella serotype K53.

Klebsiella serotype K53 is one of three strains belonging to the chemotype whose capsular polysaccharides consist of D-glucuronic acid, D-galactose, D-mannose, and L-rhamnose residues, and the structure of its polysaccharide was found to be of the "5 + 1 type" shown, of the same structural pattern as the capsule from Klebsiella K52 (Formula, see text). Nimmich has analyzed the capsular polysaccharide of Klebsiella K53 and has shown that it belongs to the chemotype that also comprises K40 and K80. As part of our continuing investigation of these polysaccharides, we now report the structure of the capsular antigen of Klebsiella K53; the structures of those from K40 and K80 are, at present, unknown.