Specific Polysaccharides

The specific, somatic polysaccharides of Smooth, Gram-negative bacteria have been studied extensively, but mostly from the biological point of view, because the Smooth forms are often virulent pathogens and it is by the specificity of the polysaccharide component that the organisms may frequently be most surely identified. 

In another study, the type 3 specific polysaccharide was obtained by extraction of organisms at pH 4 for 45 minutes at 100° in this case, the analytical figures differed a little from those of the previous preparations. Amino sugar amounted to 16% at least the greater part of this was d-glucosamine and at least the greater part of this was AT-acetylated. L-Rhamnose and D-glucose were separated, identified, and estimated as 30 % and 25%, respectively. Hexose 6-phosphate and aldoheptose phosphate were also present in small proportions. 

The sugar components of Shigella sonnei have more recently been re- 

The descriptive phase of biology is an essential prerequisite for the healthy growth of biochemistry, and the serological classification of the Salmonellas and related Enterobacteria has allowed a comprehensive and reproducible series of analyses to be made where otherwise a chaotic situation could have arisen. The Kauffmann-White Schema embraces more than the specificities due to polysaccharides of the O antigens. The H antigens, for example, are specificities due to the protein components of the flagella, and these are probably beyond the scope of chemical methods available at this time. 

The specific polysaccharides of many other Salmonella types have been studied the methods used have already been described, and the contributions cannot be detailed individually, but the results are summarized in Table IV. The Kauffmann-White Schema is based on bacterial agglutination in each serological group (A, B, C,.), organisms differ in only 

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By 1945, Stacey speculated about the possibility of a structural relationship between Pneumococcus capsular polysaccharides and those produced by other organisms. With Miss Schliichterer, he had examined the capsular polysaccharide of Rhizobium radicicolum. This polysaccharide gave a precipitin reaction in high dilution, not only with Type III Pneumococcus antiserum, but also mixed with antisera from other Pneumococcus types. The chemical evidence indicated that the polysaccharide resembled the specific polysaccharides of Types I and II Pneumococcus. A decade later, the acidic capsular polysaccharide from Azoto-bacter chroococcum, a soil organism, was studied. It, too, produced serological cross-reactions with certain pneumococcal specific antisera. Although the molecular structure of the polysaccharide was not established, adequate evidence was accumulated to show a structural relationship to Type III Pneumococcus-specific polysaccharide. This was sufficiently close to account for the Type III serological cross-relationship. 

In the late 1940s Stacey, with the able and enthusiastic assistance of Paul Kent, examined polysaccharide material from Mycobacterium tuberculosis human strain. From heat-killed cells, two stable, serologically specific polysaccharide fractions and a degraded bacterial glycogen were isolated and examined. 

In 1947, L-rhamnose was first recognized by Stacey as a constituent of Pneumococcus Type II specific polysaccharide. This finding was confirmed, in 1952, by Kabat et al. and in 1955 again by Stacey when 2,4- and 2,5-di-O-methyl-L-rhamnose were synthesized and the former was shown to be identical with a di-O-methylrhamnose, obtained by hydrolysis of the methylated polysaccharide. This result indicated a pyranose ring structure for the rhamnose units in the polysaccharide. Announcement of the identification of D-arabinofuranose as a constituent of a polysaccharide from M. tuberculosis aroused considerable interest. The L-enantiomer had been found extensively in polysaccharides, but reports of the natural occurrence of D-arabinose had been comparatively rare. To have available reference compounds for comparison with degradation products of polysaccharides, syntheses of derivatives (particularly methyl ethers) of both d- and L-arabinose were reported in 1947. 

Some Physical Properties of the Specific Polysaccharides from the Types I, II and III Pneumococcus," B. R. Record and M. Stacey,/. Chem. Soc., (1948) 1561-1567. 

Immunopolysaccharides. Part IV. Structural Studies on the Type II Pneumococcus Specific Polysaccharide, K. Butler and M. Stacey, J. Chem. Soc., (1955) 1537-1541. 

In several polysaccharides containing glycuronic acid residues, the carboxyl groups of these are linked to the amino group of amino compounds, forming amides. In the simplest examples, these are primary amides, such as the 2-formamido- and 2-acetamido-2-deoxy-D-galacturonamide (49) residues in 0-specific polysaccharides from different strains of Pseudomonas... 

There are solitary examples of other alditol phosphates as components of this class of polymers. Arabinitol 1-phosphate is part of the S. pneumoniae type 17F capsular polysaccharide. o-Glucitol 6-phosphate is a component of the group-specific polysaccharide from group B Streptococcus, which has a most unusual, ramified structure. In a polysaccharide from Nocardia... 

A structural study on lipid A and the O-specific polysaccharide of the lipopoly-saccharide from a clinical isolate of Bacteroides vulgatus from a patient with Crohn s disease was conducted by Hashimoto and coworkers [39]. They separated two potent virulence factors, capsular polysaccharide (CPS) and lipopolysaccharide (LPS), from a clinical isolate of B. vulgatus and characterized the structure of CPS. Next, they elucidated the strucmres of O-antigen polysaccharide (OPS) and lipid A in the LPS. LPS was subjected to weak acid hydrolysis to produce the lipid A fraction and polysaccharide fraction. Lipid A was isolated by PLC, and its structure was determined by MS and NMR. 

Specific Polysaccharide of some Strains of Chromobacterium vioiaceum. Biochem. J. 64, 22 P (1956). 

Saliva begins the process of chemical digestion with salivary amylase. This enzyme splits starch molecules into fragments. Specifically, polysaccharides, or starches, are broken down into maltose, a disaccharide consisting of two glucose molecules. Salivary amylase may account for up to 75% of starch digestion before it is denatured by gastric acid in the stomach. 

Type IV Pneumococcus Specific Polysaccharide.—This capsular material110 ([ck]d + 33°, water) has been hydrolyzed and shown to contain units of D-glucose and N-acetyl-hexosamine. Its structure has not yet been studied. 

The specific polysaccharide of the dominant O somatic antigen of Shigella dysenteriae has been shown to be electrophoretically and ultra-centrifugally homogeneous, and to possess a molecular weight of 26,000 from sedimentation and diffusion measurements.2601... 

The important conclusion is that much of the wall s ferulic acid is linked to specific hydroxy groups on specific sugars of specific polysaccharides. The specificity is particularly notable in the case of Fer-Ara2, since the feruloylated arabinose residues are in the rare pyranose ring-form (17). It is clear that the feruloylation reactions are not random, but are carefully steered biosynthetic steps. 

Fig. 3. Top Resolution-enhanced 600 MHz H NMR spectrum of the octasaccharide repeating unit from Hafnia alvei strain 2 O-specific polysaccharide, (a)-(g) 500 MHz ID TOCSY subspectra with selective excitation of the respective anomeric proton resonances, (h) ID TOCSY subspectrum with the H3eq resonance of the neuraminic acid residue selectively excited. (Reproduced (adapted) with permission from Gamian et al. [25J. Copyright 1991...

Barker and coworkers have applied gel chromatography in studies of pneumococcal polysaccharides.121 Purification of the type-specific polysaccharide of Pneumococcus Type II was effected by chromatography on Sephadex G-200 in M sodium chloride in this way, the ribonucleic acid, a persistent impurity in preparations of this polysaccharide, was almost completely removed. The complex formed between the polysaccharide and the nucleic acid is largely dissociated in M sodium chloride, so that the two are free in this solvent and may be separated on the basis of their differing molecular size. 

W. Jachymek, J. Czaja, T. Niedziela, C. Lugowski and L. Kenne, Structural studies of the -specific polysaccharide of Hafnia alvei strain PCM 1207 lipopolysaccharide, Eur. J. Biochem., 1999, 266, 53-61. 

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. 

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