Teichoic acids hydrolysis

Flo. 9—Alkali-stable Phosphodiester Produced by Hydrolysis of Teichoic Acids with Alkali. 

Titration of the products of alkaline hydrolysis of the teichoic acid from L. arabinoms showed that 7-8% of the phosphate groups remain as phos-... 

Fio. 11.—Hydrolysis hy Alkali of a Glycerol Teichoic Acid Containing 1,2-Phospho-dicBter Linkages. 

Pig. 14.—Hydrolysis of the Teichoic Acid from Staphylococcus lactis by alkali. 

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 production of ribitol diphosphates on acid hydrolysis, and also on alkaline hydrolysis, of the product obtained after oxidation of the teichoic acid with periodate establishes the presence of ribitol phosphate residues joined to each other through phosphodiester groups. On oxidation of the polymer (o-alanine removed) with periodate, many of the ribitol residues were oxidized, and the quantitative data obtained support a structure in which there are 7-8 units in the chain. 

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... 

Poly(ribitol phosphate) synthetase has been found in particulate fractions from Staphylococcus aureus H, and Lactobacillus plantatrum.lt ll-m The bulk of the activity in Lactobacillus plantarum was in crude, cell-wall preparations, and the enzyme is apparently located in the membrane, although intimate association with the wall itself has been suggested. Unlike the natural teichoic acid, the enzymically synthesized ribitol phosphate polymer was readily extracted with phenol hydrolysis by acid and by alkali gave the expected products, and oxidation with periodate indicated a chain length of 5-9 units, a value which compares well with that of 8 units for the natural polymer in the walls of this organism. 

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