Structure of the O-polysaccharide of Erwinia carotovora ssp carotovora GSPB 436

Abstract

The O-polysaccharide of a phytopathogenic bacterium, Erwinia carotovora ssp. carotovora GSPB 436, was studied by sugar and methylation analysis, along with H-1 and C-13 NMR spectroscopy. The following structure of the branched tetrasaccharide repeating unit of the O-polysaccharide was established: alpha-D-Glcp-(1-->3) down arrow ->3)-beta-L-Rhap-(1-->4)-alpha-L-Rhap-(1-->3)-alpha-D-Fucp-(1--> The O-polysaccharide contains a minor proportion of 4-O-methylrhamnose, which is suggested to terminate the polymer main chain. (C) 2003 Elsevier Ltd. All rights reserved.