Bacteria teichoic acids

Lipoteichoic acids (from gram-positive bacteria) [56411-57-5J. Extracted by hot phenol/water from disrupted cells. Nucleic acids that were also extracted were removed by treatment with nucleases. Nucleic resistant acids, proteins, polysaccharides and teichoic acids were separated from lipoteichoic acids by anion-exchange chromatography on DEAE-Sephacel or by hydrophobic interaction on octyl-Sepharose [Fischer et al. Ear J Biochem 133 523 1983]. 

FIGURE 9.25 Teichoic acids are covalently linked to the peptidoglycan of Grampositive bacteria. These polymers of (a, b) glycerol phosphate or (c) ribitol phosphate are linked by phosphodiester bonds. 

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. 

The major type-specific antigens of Gram-positive bacteria are the teichoic acid moieties associated with the cell wall (see Chapter 1). 

Neuhaus FC, Baddiley J (2003) A continuum of anionic charge structures and functions of D-alanyl-teichoic acids in Gram-positive bacteria. Microbiol Mol Biol R 67 686-723... 

The cell walls of most Gram-positive bacteria contain (1 ->3) poly(glycerol phosphate) teichoic acids which can bear D-alanyl or glycosyl substituents.56 However, the cell walls of Bacillus stearothermophilus B65 contain a glycerol teichoic acid which is free of substituents.57 This is contrary to evidence that had been obtained from biosynthetic studies.58... 

Teichoic and teichuronic acids. The cell walls of gram-positive bacteria are composed of a thick peptidoglycan layer which also contains proteins and additional polymers known as teichoic acids and teichuronic acids. In some species these account for 50% of the dry weight of the cells.598 599 Teichoic acids are high polymers of the following general types ... 

Although it would be out of place to give here an extensive account of the surface anatomy of bacteria, current interest in the exact location of compounds in the anatomical components of cells, for example, in membranes, granules, mitochondria, and ribosomes, requires a reasonably precise description of the location of teichoic acids. In its turn, this requires an understanding of the main features of the outer regions of bacteria. Gram-positive bacteria possess a rigid cell-wall which is responsible for... 

Membrane teichoic acids have now been detected in a large number of bacteria, including almost all of the Gram-positive organisms examined. Nevertheless, the proportion present is sometimes small, and separation of the acids from other macromolecular cell-components, such as nucleic acids, peptides, and polysaccharides, is difficult. Consequently, few have been obtained in an amount and of a purity adequate for detailed chemical study. Even from the limited studies so far made, it is clear that structural details differ considerably from case to case, and it is convenient to classify these teichoic acids according to the organisms from which they have been isolated. 

The walls of Gram-positive bacteria, unlike the membranes, sometimes do not contain teichoic acids. However, there are numerous examples of walls which do contain these compounds in substantial proportions, although in relatively few cases has detailed structural work been carried out. The purification of wall teichoic acids is often much more readily achieved than for the membrane polymers. Addition of ethanol to trichloroacetic acid extracts of walls gives a precipitate which is usually pure teichoic acid. Extraction is effected at low temperatures, and for a reasonably short time, in order to avoid extensive degradation of the polymers under the acidic conditions. Consequently, although walls may contain 20-50% by weight of teichoic acid, practiced yields are generally rather low. 

Glycerol teichoic acids have been detected in the walls of a number of bacteria. By chromatographic observation of the products formed on... 

Teichoic acids (TAs), naturally occurring polyphosphates of substituted glycerol (7) or ribitol (2) in the simpler cases, are biopolymers isolated from the cell walls (wall TAs) or membranes [membrane TAs or lipoteichoic acids (LTAs)] of various Grampositive bacteria ... 

LAB are Gram-positive bacteria with cell wall components such as peptidoglycan, polysaccharide, and teichoic acid, all of which have been shown to have immunostimulatory properties. In addition to cell wall components, immunostimulatory effects were observed with antigens originated from the cytoplasms of some strains of LAB. 

The exterior surface of Gram-positive bacteria is covered by teichoic acids. These are ribitol-phosphate or glycerol-phosphate polymer chains that are frequently substituted by alanine and glycosidically linked monosaccharides (Figure A2.4). They are attached to the peptidoglycan by a phosphate diester link. Teichoic acids can act as receptors to bacteriophages and some appear to have antigenic properties. 

The cell wall of staphylococci is composed essentially of peptidoglycan and teichoic acids. As pointed out earlier (p. 150) substances of higher molecular weight can readily cross the wall of these organisms, a property that probably accounts for their greater sensitivity than Gram-negative bacteria... 

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