STRUCTURAL STUDIES OF THE CAPSULAR POLYSACCHARIDE (S-21) FROM KLEBSIELLA-PNEUMONIAE ATCC-31314

The structure of the polysaccharide (S-21) elaborated by Klebsiella pn eumoniae ATCC 31314 has been investigated. NMR spectroscopy, sugar and methylation analysis, uronic acid degradation, and partial hydrolysis to oligosacccharides were the main methods used. In order to obtain g ood NMR spectra, the polymer was subjected to non-specific degradation by treatment with fuming hydrochoric acid. It is concluded that S-21 is composed of pentasaccharide repeating units with the following stru cture. [GRAPHICS] Approximately 0.7 equivalent of 0-acetyl group, dist ributed over at least three positions, was also present but not locate d. The carbohydrate backbone in S-21 is identical to that of Klebsiell a K30 and K33 capsular polysaccharides.