Structure of the capsular polysaccharide of Klebsiella K-type 63.

Structural investigation of the capsular polysaccharide from Klebsiella K type 63 by methylation analysis, periodate oxidation, and uronic acid degradation showed the repeating unit to consist of leads to 3)-alpha-D-Galp-(1 to 3)-alpha-D-GalpA-(1 TO 3)-ALpha-L-Fucp(1 to. This structure is identical to that of Escherichia coli serotype K-42 capsular polysaccharide. The 1H- and 13C-n.m.r. spectra of the original and modified polysaccharide are consistent with the foregoing structure.