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A R Archibald

Publications and source records attributed to A R Archibald.

52 records · Page 3Linked to original sources
PubMed1969

The action of dilute aqueous NN-dimethylhydrazine on bacterial cell walls.

1. Walls of certain Gram-positive bacteria dissolved on incubation with dilute aqueous NN-dimethylhydrazine in the presence of air, by a reaction that probably involves free radicals. 2. Under the conditions described, the soluble products from the peptidoglycan were almost all non-diffusible. After brief incubation of walls of some organisms with reagent, part of the peptidoglycan component was obtained as a high-molecular-weight gel, the viscosity of which was rapidly decreased by incubation with lysozyme. 3. The extent to which peptidoglycan dissolved varied with different organisms, depending possibly on the extent of cross-linking, but the nature of the bonds that were destroyed has not been established. 4. Teichoic acids and polysaccharides were solubilized by this treatment and could be isolated in high overall yield. 5. The procedure is valuable in the examination of the distribution of heteropolymers in walls, and has been used to show that the polysaccharide present in walls of Lactobacillus arabinosus 17-5 is phosphorylated and may account for 20% of the total phosphate of the wall.

Bacillus megaterium↗
PubMed1969

Teichoic acids possessing phosphate-sugar linkages in strains of Lactobacillus plantarum.

Cell walls of strains of Lactobacillus plantarum lacking the group D precipitinogen (a glucosylribitol teichoic acid) contain glucosylglycerol teichoic acid in which the glycosidic substituents are attached to the primary hydroxyl group of glycerol. Three distinct repeating units have been isolated from the teichoic acid preparation of strain C106, indicating either that the polymer is complex or that the wall contains a mixture of teichoic acids. Walls of streptobacteria differ from those of L. plantarum and contain neither teichoic acid nor diaminopimelic acid.

Antigens↗
PubMed1968

The glycerol teichoic acid of walls of Staphylococcus lactis I3.

1. The teichoic acid from walls of Staphylococcus lactis I3 was isolated by extraction with trichloroacetic acid and shown to contain glycerol, N-acetylglucosamine, phosphate and d-alanine in the molecular proportions 1:1:2:1. The alanine is attached to the polymer through ester linkages. 2. Hydrolysis with acid gave alanine, glucosamine and glycerol diphosphates. Under mild acid conditions a repeating unit was produced; this consists of glycerol diphosphate joined through a phosphodiester group to N-acetylglucosamine. 3. Hydrolysis with alkali gave glycerol diphosphates, saccharinic acid and two phosphodiesters containing glucosamine whose structures were elucidated; these both contain glucosamine 1-phosphate, and N-acetylglucosamine 1-phosphate was isolated by a degradative procedure. 4. The unusual properties of the teichoic acid are explained by a polymeric structure in which N-acetylglucosamine 1-phosphate is attached through its phosphate to glycerol phosphate. 5. The biosynthetic implications of this structure are discussed.

Acids↗
PubMed1968

The membrane teichoic acid of Staphylococcus lactis I3.

1. Teichoic acid was isolated by extraction with trichloroacetic acid of the membrane fraction of disrupted cells of Staphylococcus lactis I3. 2. The purified material contains glycerol, phosphate and alanine, but little or no sugar or amino sugar. 3. A study of the products of hydrolysis with acid and alkali established that the membrane teichoic acid is a (1-->3)-linked poly(glycerol phosphate) that differs in structure from the glycerol teichoic acid in the wall of this organism. 4. The alanine ester residues show the characteristic high lability to alkali and are thus distinguishable from the more stable alanine ester residues of the wall teichoic acid. 5. The significance of these structural features and the possible function of teichoic acids are discussed.

Acids↗
PubMed1968

The glycerol teichoic acid from walls of Staphylococcus epidermidis I2.

1. Walls of Staphylococcus epidermidis I2 contain 30% (w/w) of a glycerol teichoic acid containing phosphate, d-alanine and d-glucose in the molecular proportions 1:0.25:0.50. 2. The teichoic acid was isolated by extraction with trichloroacetic acid and with dilute aqueous NN-dimethylhydrazine at pH7, and was shown to be a (1-->3)-linked poly(glycerol phosphate) containing beta-d-glucopyranosyl and d-alanyl ester substituents. 3. 2-O-beta-d-Glucopyranosylglycerol was isolated and characterized as its crystalline hexa-O-acetate. 4. Unlike that of certain other bacteria, the peptidoglycan component of the wall is not solubilized by NN-dimethylhydrazine. 5. The membrane teichoic acid is also a (1-->3)-linked poly(glycerol phosphate) but contains a smaller proportion of glucosyl substituents.

Alanine↗
PubMed1965

The molecular structure of bacterial walls. The size of ribitol teichoic acids and the nature of their linkage to glycosaminopeptides.

1. Ribitol teichoic acids prepared by fractional precipitation of trichloroacetic acid extracts of bacterial cell walls are essentially undegraded and have similar chain length to the teichoic acid originally present in the walls. 2. The chain length of teichoic acid can be determined directly, without prior extraction from the wall. Accurate values have been obtained by measurement of the formaldehyde produced by oxidation of walls with periodate. Less accurate values have been derived from the amount of inorganic phosphate formed by heating walls at pH4. 3. The relative amounts of N-acetylglucosaminylribitol and its mono- and di-phosphates produced by heating walls of Staphylococcus aureus with alkali agree with the amounts calculated for the hydrolysis of teichoic acid having the chain length determined by other methods. 4. Chemical considerations indicate that the linkage between teichoic acid and the wall may involve a phosphoramidate bond between the terminal phosphate of the teichoic acid and one of the amino groups in the glycosaminopeptide.

Cell Wall↗