Acidic constituents, capsular polysaccharides

Epimerization at C-2 of UDP-GlcNAc, leading to the UDP derivative of 2-acetamido-2-deoxy-D-mannose, was also observed115 118 the monosaccharide was identified as a constituent of several capsular polysaccharides from Streptococcus pneumonia119-122 and Neisseria meningitidis group A (Ref. 123), the teichuronic acid of Bacillus cereus,124 and the O-specific... 

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. 

The 3-deoxy-D-ma/ino-2-octulosonic acid 8-phosphate synthase (KDO synthase or KdoS EC 4.1.2.16) is an enzyme involved in the biosynthesis of the eight-carbon sugar KDO [63], a constituent of the capsular polysaccharides (K-antigens) and outer membrane lipopolysaccharides (LPS, endotoxin) of Gram-negative bacteria [156], as well as of the cell wall of algae and a variety of plants [157], In vivo, the enzyme catalyzes the irreversible addition of 26 to D-arabinose 5-phosphate (Ara5P, 32) to form KDO 8-phosphate 33 [158]. The... 

Glucuronic acid is also constituent of pathogenic bacteria. The simplest structure for a pneumococcal capsular polysaccharide has the repeating unit [- 4)-/3-d-G1c-(1 3)-/3-D-GlcpA-(l ]ra.120... 

The uridine diphosphate ester derivatives in a non-capsulated. Type II pneumococcus and a capsulated. Type III pneumococcus were investigated by Smith, Mills, and Harper." The capsule of the Type III pneumococcus is composed of a polysaccharide having 4-0-( 8-D-glucopyranosyluronic acid)-D-glucose as a repeating unit. n-Glucuronic acid, D-glucose, and L-rhamnose are constituents of the capsular polysaccharide of the Type II pneumococcus. 

Pneumococcus Group or C) Polysaccharide.—This substance, fajo -h 61° (water), is the polysaccharide constituent of the somatic part of the cell, and is common to all the pneumococcus types. It shows group specificity and is generally similar to the Type IV capsular polysaccharide. Its constituent units are probably N-acetyl-D-glucosamine, a hexose and phosphoric acid. It may be termed the carbohydrate residue of the heterophile antigen (described below) of pneumococcus which was separated by Goebel and his coworkers. 

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