STRUCTURE OF A PHOSPHORYLATED POLYSACCHARIDE FROM SHEWANELLA-PUTREFACIENS STRAIN S29

A phosphorylated polysaccharide was isolated from the aqueous layer of the phenol-water extract of a non-halophilic bacterium Shewanella put refaciens strain S29. The glycosyl phosphate linkage in the polysaccha ride was split under mild acid conditions to give, after borohydride r eduction, a phosphorylated oligosaccharide-alditol. On the basis of su gar analysis and H-1, C-13 and P-31 NMR spectroscopy, including 2D COS Y, relayed COSY, rotating-frame NOE spectroscopy (ROESY), heteronuclea r C-13, H-1 COSY, and H-detected heteronuclear H-1, P-31 multiple-quan tum coherence (HMQC), it was concluded that the polysaccharide is buil t up of tetrasaccharide-phosphate repeating units having the following structure: [GRAPHICS] where QuiNAc and Qui4NAc are 2-acetamido-2,6-di deoxyglucose and 4-acetamido-4,6-dideoxyglucose, respectively. (C) 199 7 Elsevier Science Ltd.