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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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Teichoic acids, the cell wall anionic polymers of Gram-positive bacteria, manifest structural diversity due to variation of the type of the phosphodiester bonds in the polymer core and the nature and the combination of the constituents. To date, teichoic acids of a wide group of bacteria, predominantly of the order Actinomycetales, have been investigated. On the other hand, teichoic acids of bacilli cell walls where these polymers were discovered in 1958 are explored to a much lesser extent. Here we present the results of structural studies of teichoic acids and sugar 1-phosphate polymers of 22 VKM strains of the Bacillus subtilis group. The cell walls of the strains investigated, contain poly(polyol phosphate) and poly(glycosylpolyol phosphate) (the type I and type II teichoic acids, respectively). Their structures were established by chemical and NMR spectroscopic methods. Structural variations in teichoic acids of the type I were revealed, viz., the presence of 1,3-poly(glycerol phosphate) with α- and β-D-Glcp, α- and β-D-GlcpNAc substituents and 1,5-poly(ribitol phosphate) with α- and β-D-Glcp and β-D-GlcpNAc substituents. The α-linked glucose constituent is identified for the first time in ribitol teichoic acids . The core of the type II teichoic acids was represented by one general structure, viz., glycosyl(11/2)glycerol linked by phosphodiester bonds between the hydroxyl groups at C(3) of glycerol and C(6) of a sugar component (α- and -D-Galp, -D-Glcp and -D-GlcpNAc). A new structure with a disubstituted core glycerol residue, -6)-α-D-Glcp-(1→1)-[β-D-Glcp-(1→2)]-sn-Gro-(3-P- , was found in B. subtilis VKM B-764. A new structural type of teichoic acids was identified in B. subtilis VKM B-762. The phosphodiester bond links the hydroxyl groups at C(3) of glycerol and C(2) of glyceric acid, which N-acylates the 4-aminoquinovose residue of the chain: -2)-GroA4NQuip-(1Gro-(3-P-. Teichoic acids of all the bacilli studied contain O-linked, partially N-acetylated D-alanine residues. Cell walls of four strains of B. subtilis were found to contain, in addition to teichoic acids, disaccharide 1-phosphate polymers of the following structures: -3)--D-GalpNAc-(16)--D-Glcp-(1-P- (B. subtilis ssр. subtilis ВКМ B-501T ) and -4)--D-GlcpNAc-(16)--D-Galp-(1-P- with the GlcpNAc residue partially O-acetylated at O(3) and O(6) (B. subtilis ssр. spizizenii VKM B-720, VKM B-916 and B. subtilis VKM B-761). Thus, in our studies of cell wall polymers of 22 VKM strains of bacilli a variety of teichoic acids and sugar 1-phosphate polymers were revealed. The results obtained can be of value in the taxonomy of B. subtilis for the differentiation, based on the composition and structure of cell wall polymers, of closely related strains.