Induced circular dichroism study of the aqueous solution complexation of cello-oligosaccharides and related polysaccharides with aromatic dyes.
Carbohydr Res
; 265(2): 181-95, 1994 Dec 16.
Article
em En
| MEDLINE
| ID: mdl-7842441
ABSTRACT
Acetobacter xylinum, grown in the presence of low levels of the water-soluble dye Calcofluor White ST produces a pellicle of cellulose that has no detectable crystallinity. Biological factors of this sort are probably more important than physical factors in controlling the higher order structures of celluloses. Circular dichroism (CD) is induced by complexes that are formed by specific interactions between chiral oligosaccharides and dye molecules. Using CD, equilibrium constants were measured for the association reactions between various dyes with a series of cello-oligosaccharides (n = 2-6), methylcellulose, hydroxypropylcellulose (HPC), amylose, cyclomalto-oligosaccharides (cyclodextrins), and the linear malto-oligosaccharides (n = 3-7). Possible structural features of the complexes are discussed. Dyes that are capable of binding to the higher cello-oligomers in aqueous solutions are the same dyes that modify the solid structure of bacterial cellulose. An analogy between the binding of water-soluble dyes to cello-oligosaccharides and the binding of the cellulose-degrading enzyme, cellobiohydrolase I, to cellulose is discussed.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligossacarídeos
/
Polissacarídeos Bacterianos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Carbohydr Res
Ano de publicação:
1994
Tipo de documento:
Article