RESUMO
The major cell wall polymer of Streptomyces sp. VKM Ac-2125, the causative agent of potato scab, is galactomannan with the repeating unit of the following structure: [carbohydrate structure in text] The polysaccharide with such a structure is found in the bacterial cell wall for the first time. The cell wall also contains small amount of a teichoic acid of the poly(glycerol phosphate) type and 3-deoxy-D-glycero-D-galacto-non-2-ulopyranosonic acid.
Assuntos
Parede Celular/química , Mananas/análise , Mananas/química , Streptomyces/química , Sequência de Carboidratos , Galactose/análogos & derivados , Espectroscopia de Ressonância MagnéticaRESUMO
Structures of cell wall anionic polymers of the strain Streptomyces sp. VKM Ac-2124, a causative agent of potato scab, which is phylogenetically the closest to plant pathogenic species S. setonii and S. caviscabies, were studied. The strain contains three anionic glycopolymers, viz., a teichuronic acid with a disaccharide repeating unit -->6)-alpha-d-Glcp-(1-->4)-beta-d-ManpNAc3NAcA-(1-->, a beta-glucosylated polymer of 3-deoxy-d-glycero-d-galacto-non-2-ulopyranosonic acid (Kdn), and a beta-glucosylated 1,5-poly(ribitol phosphate). The strain studied is the second representative of plant pathogenic streptomycetes inducing potato scab disease, the cell wall anionic polymers of which were shown to contain a Kdn-polymer. Presumably, the presence of Kdn-containing structures in the surface regions of pathogens is essential for their efficient attachment to host plant cells.