Agrobacterium polysaccharide

De Castro, C., De Castro, O., Molinaro, A., Parrilli, M., Structural determination of the O-chain polysaccharide from Agrobacterium tumefaciens, strain DSM 30205. Eur J Biochem/FEBS 269 (2002) 2885-2888. 

De Castro, C., Sturiale, L., Parrilli, M. Characterisation of the alpha-(l->3) homopolymer of h-glycero-D-manno-heptoss units isolated from the O-chain polysaccharide of Agrobacterium radiobacter. Eur J Org Chem 2004 (2004) 2436-2440. 

Curdlan is a bacterial polysaccharide made by Agrobacterium biovar [87,88,89]. It is a linear (1 3)- -glucan (MW 73,000) that forms a triple helix. Curdlan is insoluble in cold water. When aqueous dispersions of curdlan are heated, two types of gels form. First curdlan dissolves. When the solution reaches 55-66 °C, then is cooled, a reversible gel forms. The gel melts when held at about 60 °C. When the thermoreversible gel is heated to a temperature above 80 °C, an irreversible gel forms. Heating to higher temperatures results in stronger irreversible gels. Transition temperatures are a function of concentration. 

This polysaccharide appears to be identical with a glucan (isolated from cultures of Agrobacterium tumefaciens) in which the main linkage between the D-glucose residues is - )S-D-(1 —> 2). The synthetic glucan obtained with active preparations from Rhizobium japonicum contains, in addition to this linkage, some )3-D-(l — 3)-... 

Extracellular polysaccharides composed of o-glucose, pyruvic acid, and succinic acid have been isolated from a number of strains of Agrobacterium. The conformational behaviour of the extracellular gel-forming polysaccharides from Arthrobacter species has been investigated by nuclear magnetic resonance relaxation and optical rotation techniques. " A number of the polysaccharides studied showed evidence of an ordered conformation which could be melted out on heating. O-Deacetylation destroyed the ordered conformation of two A. viscosus polysaccharides, whilst O-deacylation of the A. stabilis polysaccharide stabilized the ordered structure. 

In the case of agricultural applications it may be possible to improve on the natural functions of certain bacterial polysaccharides. At Norwich studies have concentrated on the possible biological and ecological roles played by the EPS secreted by the soil bacteria Agrobacterium and Rhizobium. 

Obtained by separating the polysaccharides that yield microorganisms Agrobacterium, Alcaligenes faecalis. 

Kanchanarach W, Theeragool G, Inoue T, Yaknshi T, Adachi O, Matsushita K (2010) Acetic acid fermentation of Acetobacter pasteurianus relationship between acetic acid resistance and pellicle polysaccharide formation. Biosci Biotechnol Biochem 74(8) 1591-1597 Kaneshiro T, Law JH (1964) Phosphatidylcholine synthesis in Agrobacterium tumefaciens. I. Purification and properties of a phosphatidylethanolamine N-methyltransferase. J Biol Chem 239 1705-1713... 

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