Teichoic treatment

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]. 

Traces of an optically active anhydroribitol and its phosphates are produced when some teichoic acids are hydrolyzed with alkali.66 67 No anhydroribitol is formed by similar treatment of ribitol, its 1-, 2-, or 3-phosphates, or ribitol 1,5-diphosphate.68 However, small proportions of anhydroribitol and its phosphates are produced by the action of alkali on a synthetic poly (ribitol phosphate) prepared by the action of diphenyl phosphoro-chloridate oil 3,4-O-isopropylideneribitol l-phosphate and 2-phosphate.68 This observation suggests that 1,4-anhydroribitol (13) or its derivatives (15) are produced by fission of a phosphodiester, for example (14), in the manner indicated in Fig. 3, and that this reaction occurs together... 

The proportion of 1,4-anhydroribitol formed by treatment of teichoic acids and synthetic poly(ribitol phosphate) with alkali is small, and the major hydrolytic pathway involves the cyclic phosphate sequence. No 1,4-anhydroribitol glycosides have been observed in the alkaline hydrolyzates of teichoic acids possibly, the presence of a glycosyl substituent makes the reaction sterically less favorable than when such substituents are absent. 

A small proportion of O-D-glucosylribitol was produced directly by hydrolysis of the teichoic acid with alkali ( see Fig. 16) this product is identical with that obtained by dephosphorylation of the hydrolysis mixture. The major products of such a hydrolysis with alkali were the isomeric monophosphates (58) and (59), in which R = 0-D-glucopyranosyl, both of which gave the O-D-glucosylribitol on enzymic dephosphorylation. The isomer (58) reduced 3 molar proportions of periodate, and the ribitol residue was oxidized, whereas the isomer (59) reduced 2 molar proportions of periodate, the ribitol residue being resistant to oxidation. Small proportions of the diphosphates (56) and (57) were also produced. Oxidation of the diphosphate (57) with periodate, followed by treatment with alkali to remove the aldehydic residues, gave a ribitol diphosphate. 

The nature of the association between membrane and teichoic acid is unknown, and it is possible that these teichoic acids are chemically attached to other components of the cell. Samples obtained by extraction with phenol appear to have appreciably higher molecular weight than has the purified teichoic acid obtained by extraction with trichloroacetic acid, and it is likely that the prolonged, acid treatment used in earlier work may have caused hydrolysis of some of the phosphodiester linkages. It is noteworthy that this comment on earlier studies does not apply to ribitol teichoic acids. Detailed examination of preparations of membrane teichoic acid obtained by less drastic conditions is highly desirable, in order to confirm the supposed size of the naturally occurring polymers, as well as... 

Synthetic ribitol phosphate polymer, unlike teichoic acid in a wall, is readily extracted from the particulate enzyme or membrane preparation by treatment with phenol.18 Similarly, teichoic acid synthesized by intact cells in the presence of penicillin is only loosely attached to the wall,111 and it may be significant that, in each case, synthesis of teichoic acid has occurred without the simultaneous synthesis of glycosaminopeptide. It is now known that, in the normal wall, teichoic acid and glycosaminopeptide are attached to each other, and it has been suggested that the low activity of cell-free synthetase is due to the absence of suitable acceptor molecules of glycosaminopeptide. This possibility could account for the ease of removal of teichoic acid formed when simultaneous synthesis of glycosaminopeptide was not possible. 

Teichoic acids have also been implicated in the extracellular secretion of enzymes by bacteria. Treatment of Bacillus amyloliquefaciens with tunicamycin, an antibiotic known to inhibit cell wall synthesis, produced cells that were deficient in teichoic acid and did not secrete a-amylase. The a-amylase was found to be cell bound. The accumulation of a-amylase in the cell was also observed when teichoic acid synthesis was inhibited by culturing the organism in a medium that was limited in phosphate. Further evidence of the involvement of teichoic acids in protein secretion was obtained by using mutants that did not synthesize teichoic acids. These mutants also had a marked decrease in the amount of a-amylase that was secreted [204]. 

Beneficial effects of probiotic consumption in the prevention and treatment of several gastrointestinal diseases, such as inflammatory bowel diseases, antibiotic associated-diarrhoea, neonatal necrotizing enterocolitis, irritahle bowel syndrome, Helicobacter pylori infection, as well as food allergies and intolerances, have been clearly assessed (Sanders et al. 2013). Furthermore, probiotics are effective in reducing cholesterol levels and lowering blood pressure (Kumar et al. 2012). However, molecular mechanisms underlying strain-specific probiotic action and the identity of effector molecules (peptidoglycan, teichoic acid, cell surface polysaccharides, extracellular proteins) still remain to be fully elucidated. 

Teichoic acid was removed from the cell wall by preliminary trichloroacetic acid treatment, and successive extractions with the same solvent gave a solution, from which teichan was precipitated with cetylpyridinium bromide. The product was purified by ethanol precipitation, and from 1.2 g of dry cell wall material, 81 mg was obtained. 

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