Antigens pneumococcus polysaccharide

The study of serological precipitation reactions is complicated by the fact that ordinarily these reactions involve two proteins, the antigen and the antibody. The understanding of these reactions was greatly advanced by the introduction into their study of precise microanaljrtical methods and a further simplification involving the use of a nitrogen-bree multivalent hapten of pneumococcus polysaccharide. A few years ago it was reported... 

Tetanus, diphtheria Characterized single/combined antigens Pertussis PT -b FHA -b LPF -b PSA -b 69kD, Pneumococcus polysaccharides (23), Menningococcus polysaccharides Polysaccharide-protein conjugates Haemophilus b, Pneumococcus ... 

Eleven IgA myeloma proteins that precipitate with Pneumococcus C polysaccharide (PnC) have been described.65-69 This antigen has a structure whose general features are known,70 71 and it is a somatic, species-specific polysaccharide. 

In order to provide access here to information about other microbial polysaccharides, there follows a short review of reviews. The Chemical Nature of Bacterial Antigens is a source of information on the earlier work, and this was followed by two reviews - in the present Series in one of these, the bacterial homopolysaccharides were discussed and some of the more complex products were mentioned. A wide review of mucopolysaccharides and mucoproteins included references to many bacterial polysaccharides, and, subsequently, an account of the specific polysaccharides of the Gram-positive Pneumococcus, and of dextrans, levans, and products of Gram-negative forms appeared. There followed a comprehensive review of pneumococcal polysaccharides, and an account restricted to products of Mycobacterium tuberculosis appeared in 1948. A broad coverage was provided in 1950, in this case the products of pathogenic species being dealt with more particularly this work encompassed the basis of the more... 

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. 

Isol. from the partial acid hydrolysate of type Vni Pneumococcus specific polysaccharide. Constit. of the repeating unit of the O-antigen of Salmonella muenster Ei and of the 0-antigen of E. coli serotype 0111. 

Capsules of pneumococci consist largely of a polysaccharide slime, but they contain in addition some protein and small amounts of other substances. The type-specificity and virulence of the pneumococci are due to their capsular polysaccharides (see Chapter VIII). The specificity of reaction for different pneumococcal types is due to variation in the capsular polysaccharide molecules. The antigenic polysaccharides are isolable from the bacteria but are more often prepared from the culture broth into which they are liberated by bacterial autolysis. Though there are more than 70 known types of pneumococci, little is known of the structures of their capsular polysaccharides save that from type III pneumococcus. This is shown to be a linear molecule of D-glucose and D-glucuronic acid units in equal amounts. They are linked alternately so that the molecule may be regarded as a chain of aldobiouronic acid units 131) ... 

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