Teichoic acids bacterial polysaccharides

Five pentoses, namely, D-ribose, d- and L-arabinose, and D- and L-xylose, have been found in hydrolyzates of bacterial polysaccharides. D-Riboseisthe most common of these, and is a component of different LPS, capsular polysaccharides, and teichoic acid type of polymers. In all these polymers, it occurs as the /I-furanosyl group or residue. 

Many bacterial polysaccharides contain phosphoric ester groups. There is a limited number of examples of monoesters. More common are phosphoric diesters, connecting an amino alcohol or an alditol to the polysaccharide chain. Another possibility is that oligosaccharide or oligosaccharide-alditol repeating units are connected to a polymer by phosphoric diester linkages. In addition to the intracellular teichoic acids, several bacteria, for example, different types of Streptococcus pneumoniae, elaborate extracellular polymers of this type. These polymers are generally discussed in connection with the bacterial polysaccharides. 

A variety of glycans with important stmctural and functional roles are produced as part of bacteria cell walls. Capsular polysaccharides (CPS), teichoic acids, and lipopolysaccharides (LPS) are the three most important and represent the bacterial first line of defense against complement and bacteriophages. The carbohydrate portion of this glycoconjugate contains the major antigenic determinants that distinguish various serotypes of bacteria [1]. 

Bacterial polysaccharides can also serve as markers to identify specific bacterial species or genera. Typical microbial polysaccharides include peptidoglycans, lipopolysaccharides, and teichoic/teichuronic acids. Some markers such as muramic acid, D-alanine, and p-hydroxy myristic acid are present in the polysaccharides from eubacteria but are uncommon in higher life forms such as plants and animals. Pyrolysis results on bacterial polysaccharides were discussed in Sections 7.9 and 7.10. Specific pyrolysis products such as propionamide or peaks characteristic for KDO have been used for Py-MS or Py-GC/MS characterization of microorganisms. 

Duckworth, M. (1977). Teichoic Acids in Surface Carbohydrates of the Prokaryotic Cell (Sutherland, I.W. ed.). Academic Press, London, New York, San Francisco, pp. 177-208. Jann, K. and Jann, B. (1977). Bacterial Polysaccharide Antigens in Surface Carbohydrates of the Prokaryotic Cell (Sutherland, I.W. ed.). Academic Press, London, New York, San Francisco, pp. 247-287. 

Phosphopolysaccharides (polysaccharide phosphate esters) of this kind occur frequently in living systems and in a number of important technological products. Many bacterial polysaccharides contain phosphate ester groups. In these the phosphate groups serve to link the saccharide rings to lipids or other biopolymer units as, for example, in the teichoic acids (Section 10.3). Phosphorylation is known to profoundly affect food properties (Chapter 12.4). 

Intracellular bacterial polysaccharides have not yet found proper applications they are, however, extensively studied as storage materials similar to those in humans (glycogen and as specific targets for the drug attacks of pathogens (murein, teichoic and teichonic acids ). 

Properties.— The properties of glycoside hydrolases have been reviewed. As part of a series on surface carbohydrates of the prokaryotic cell, a comprehensive chapter deals with enzymes acting on bacterial surface carbohydrates. Enzymes hydrolysing capsular and slime polysaccharides, lipopolysaccharides, and teichoic acids are treated in detail. 

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