Spectroscopic characterisation of order-disorder transitions for extracellular polysaccharides of arthrobacter species
| Autor: | David A. Rees, E. Jane Welsh, Edwin R. Morris, Arthur H. Darke |
|---|---|
| Rok vydání: | 1978 |
| Předmět: |
chemistry.chemical_classification
Extracellular polysaccharide biology Stereochemistry Organic Chemistry Relaxation (NMR) General Medicine biology.organism_classification Polysaccharide Biochemistry Protein tertiary structure Analytical Chemistry stomatognathic diseases Order (biology) chemistry Acetylation Arthrobacter Organic chemistry Bacteria |
| Zdroj: | Carbohydrate Research. 66:133-144 |
| ISSN: | 0008-6215 |
| DOI: | 10.1016/s0008-6215(00)83246-2 |
| Popis: | The conformational behaviour of the extracellular polysaccharides from Arthrobacter species of soil-borne bacteria has been investigated by nuclear magnetic resonance relaxation and optical rotation. Polysaccharides from A. stabilis, A. viscosus, and A. viscosus sp. n, in solution at room temperature, all show evidence of an ordered conformation which can be melted out on heating. The temperature course of this transition, however, shows considerable variation with bacterial species. Thus A. stabilis polysaccharide shows a very sharp conformational transition centred around 60°, whereas the transitions of the polysaccharides from both strains of A. viscosus occur over a much broader temperature-range. The transition for the polysaccharide of A. viscosus sp. n is again centred close to 60°, whereas, for A. viscosus, melting of the tertiary structure of the polysaccharide is incomplete at 100°. O -Deacetylation destroys the ordered conformation of both A. viscosus polysaccharides. The ordered structure of A. stabilis polysaccharide, by contrast, is stabilised by removal of acyl substituents (which here include succinic half-ester). Understanding of the conformational state of these materials affords considerable insight into their gelation behaviour and unusual solution rheology. The known solution interactions with certain plant polysaccharides suggest a possible biological role for Arthrobacter polysaccharides in relationships with components of plant root-systems. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|