2Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow, 117913 Russia; fax: (095) 135-5328; E-mail: knirel@ioc.ac.ru
* To whom correspondence should be addressed.
Received January 11, 2000
An acidic O-specific polysaccharide containing D-glucuronic acid (D-GlcA), 2,3-diacetamido-2,3-dideoxy-D-glucuronic acid (D-GlcNAc3NAcA), 2,3-diacetamido-2,3-dideoxy-D-mannuronoyl-L-alanine (D-ManNAc3NAcA6Ala), and 2-acetamido-2,4,6-trideoxy-4-[(S)-3-hydroxybutyramido]-D-glucose (D-QuiNAc4NAcyl) was obtained by mild acid degradation of the lipopolysaccharide of the bacterium Pseudoalteromonas sp. KMM 634 followed by gel-permeation chromatography. The polysaccharide was cleaved selectively with a new solvolytic agent, trifluoromethanesulfonic acid, to give a disaccharide and a trisaccharide with D-GlcNAc3NAcA at the reducing end. The borohydride-reduced oligosaccharides and the initial polysaccharide were studied by GLC-MS and 1H- and 13C-NMR spectroscopy, and the following structure of the linear tetrasaccharide repeating unit of the polysaccharide was established: [figure].
KEY WORDS: O-antigen, bacterial polysaccharide, Pseudoalteromonas, trifluoromethanesulfonic acid, 2,3-diacetamido-2,3-dideoxy-D-glucuronic acid, 2,3-diacetamido-2,3-dideoxy-D-mannuronoyl-L-alanine, 2-acetamido-2,4,6-trideoxy-4-[(S)-3-hydroxybutyramido]-D-glucose