Structure of the O-specific polysaccharide of the bacterium Proteus mirabilis O29

An O-specifle polysaccharide was obtained by mild acid degradation of P. mi rabilis O29 lipopolysaccharide (LPS) and found to contain 2-acetamido-2-deo xy-D-galactose and D-glucuronic acid (D-GlcA) in the ratio 3:1. Studies of the polysaccharide by H-1- and C-13-NMR spectroscopy including two-dimensio nal correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY) , nuclear Overhauser effect spectroscopy (NOESY), and H-detected H-1,C-13-h eteronuclear multiple-quantum coherence (HMQC) experiments demonstrated the following structure of the branched tetrasaccharide repeating unit: [GRAPHICS]