[New method of isolation of O-specific polysaccharide from gram-negative bacteria Yersinia pseudotuberculosis]

Using bacteria Yersinia pseudotuberculosis as an example, two procedures for obtaining the O-specific polysaccharide of endotoxins of gram-negative bacteria were compared: the direct acidic hydrolysis of whole cells and the traditional procedure based on preliminary isolation of the corresponding lipopolysaccharide. Analysis of the resulting polysaccharides showed that the isolation from the bacterial biomass gave a high yield of the polysaccharide; the polysaccharide is not degraded; and judging from the 13C NMR data, its structure was completely identical to that of the corresponding product of lipopolysaccharide hydrolysis. Therefore, this procedure is useful for obtaining O-specific polysaccharides for structural studies.