Structural investigation of the capsular polysaccharide of Klebsiella serotype K12.

Klebsiella K12 capsular polysaccharide has been investigated by the techniques of methylation, Smith degradation-periodate oxidation, uronic acid degradation, and partial hydrolysis, in conjunction with 1H-n.m.r. spectroscopy at 100 and 220 MHz, and 13C-n.m.r. spectroscopy at 20 MHz. The structure has been found to consist of the hexasaccharide repeating-unit shown, having a D-galactofuranosyl residue at the branch point. In this series, a D-galactofuranosyl residue has previously only been found in the polysaccharide from Klebsiella K41.