Revealing the Compact Structure of Lactic Acid Bacterial Heteroexopolysaccharides by SAXS and DLS.
Biomacromolecules
; 18(3): 747-756, 2017 03 13.
Article
em En
| MEDLINE
| ID: mdl-28042938
ABSTRACT
Molecular structures of exopolysaccharides are required to understand their functions and the relationships between the structure and physical and rheological properties. Small-angle X-ray scattering and dynamic light scattering were used in conjunction with molecular modeling to characterize solution structures of three lactic acid bacterial heteroexopolysaccharides (HePS-1, HePS-2, and HePS-3). Values of radius of gyration RG, cross-sectional radius of gyration RXS, approximate length L, and hydrodynamic diameter were not directly proportional to the molar mass and indicated the HePSs adopted a compact coil-like rather than an extended conformation. Constrained molecular modeling of 15000 randomized HePS-1 conformers resulted in five best-fit structures with R factor of 3.9-4.6% revealing random coil-like structure. Φ and Ψ angle analysis of glycosidic linkages in HePS-1 structures suggests Galf residues significantly influence the conformation. Ab initio scattering modeling of HePS-2 and HePS-3 gave excellent curve fittings with χ2 of 0.43 and 0.34 for best-fit models, respectively, compatible with coil-like conformation. The findings disclose solution behavior of HePS relevant for their interactions with biomacromolecules, for example, milk proteins.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Polissacarídeos
/
Lactobacillaceae
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Espalhamento a Baixo Ângulo
/
Difusão Dinâmica da Luz
Tipo de estudo:
Clinical_trials
/
Prognostic_studies
Idioma:
En
Revista:
Biomacromolecules
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Dinamarca