RESUMEN
The alkali-extractable and water-soluble fungal polysaccharide F1SS isolated from the cell wall of Acrospermum compressum has been studied by methylation analyses, reductive cleavage and 1D- and 2D-NMR spectroscopy. The polysaccharide consists of a regular disaccharide repeating unit with the structure: [structure: see text]. The mannan core was obtained by mild hydrolysis of the polysaccharide F1SS and its structure was deduced to be composed of a skeleton of alpha-(1-->6)-mannopyranan, with around 1 out of 11 residues substituted at position 2 by short chains (one to six units) of 2-substituted mannopyranoses. DOSY experiments provided molecular sizes of 60 kDa and 2.5 kDa for the polysaccharide F1SS and the Mannan core, respectively. This is the first report of a fungal mannofuranose-containing cell wall polysaccharide.
Asunto(s)
Ascomicetos , Pared Celular/química , Mananos/química , Polisacáridos/química , Ascomicetos/química , Ascomicetos/citología , Conformación de Carbohidratos , Secuencia de Carbohidratos , Mananos/aislamiento & purificación , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Polisacáridos/aislamiento & purificaciónRESUMEN
The structure of acidic fungal polysaccharides isolated from the cell wall of Plectosphaerella cucumerina, Verticillium dahliae, and V. albo-atrum has been investigated by chemical analysis, methylation analysis, and 1D and 2D 1H and 13C NMR spectroscopy. The polysaccharides have an idealized repeating block of the type: [carbohydrates: see text] linked to a small mannan core (<15%), where n=13, m=13, p=5, and q=8 for P. cucumerina, and n=16, m=16, p=6, and q <1 for both Verticillium species.
