Bacterial lipopolysaccharide fragments

D-Xyl -( 1 + 4)-D-Xyl and the ulosonlc acid-containing compounds (4) (isolation of bacterial lipopolysaccharide fragment... 

Interaction of Bacterial Lipopolysaccharide Fragments with Monoclonal Antibodies... 

Two of the most frequent monosaccharide components of bacterial polymers belonging to this group have been the subjects of articles in this Series. They are 3-deoxy-D-manno-2-octulosonic acid,247 a normal constituent of the core region of bacterial lipopolysaccharides that is also present in some other polymers, and N-acetylneuraminic acid,248 found in several capsular polysaccharides. Enolpyruvate phosphate serves as the precursor of the C-l-C-3 fragment of the monosaccharides, with D-arabinose 5-phosphate or 2-acetamido-2-deoxy-D-mannose 6-phosphate being an acceptor for transfer of the three-carbon unit. Characteristic, activated forms of these monosaccharides are the CMP derivatives. 

In bacterial lipopolysaccharides, O-specific chains composed of repeating, or modified repeating, units are linked to a unique oligosaccharide sequence of the core region which is connected to a lipid A fragment serving as a hydrophobic anchor embedded in the bacterial outer-membrane. Biosynthesis of O-specific chains was found to occur independently on formation of other structural fragments of the lipopolysaccharide molecule. Both block and monomeric mechanisms were demonstrated for the biosynthesis of these polymers. 

The capillary g.c.-e.i.- and c. i.(NH2)-m.s. of partially methylated and acetylated derivatives of 3-deoxy-2-keto-aldonlc acids and 3-deoxyaldltols has been reported in preparation for the methylatlon analysis of KDO units in bacterial lipopolysaccharides." In the c. i. ( 1-C H q )-m. s. of some branched-chain hexopyranoside derivatives (with one or two Ac, C02Me, CONH or CN groups at C-3), the [M+C Hg]" and several primary fragment ion intensities were found to be dependent upon the nature and stereochemistry of the C-3 substituent. ... 

The field is actually in a good position to contribute to the development of bacterial polysaccharide glycoconjugate vaccines. Numerous fragments of capsular polysaccharides, lipopolysaccharides, or other bacterial carbohydrates have been synthesized and their protein conjugates obtained [87]. 

Antigen adsoption is crucial (e.g., aluminum hydroxide fragment of lipopolysaccharide, a bacterial endotoxin) Active fragments of bacterial cell walls (Keitel et ah, 1993)... 

Compound 25, in which X=3,6-dideoxy-D-xy/o-hexose (abequose), and the isomer which has this sugar bonded to the mannose unit adjacent to the reducing centre, have been produced on mild acid hydrolysis of a bacterial 0-antigen fragment octasaccharide which has the abequose at the mannose units second from each end of the octamer. Heptasaccharide 26, isolated by mild hydrolysis from the lipopolysaccharide of Haemophilus ir uenzae, has been structurally characterized. ... 

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