Talose polysaccharide

Deoxy-L-galactose (L-fucose) is common, and has only been found as the a- or )3-pyranoside. The rare D-fucose has, however, been found both as a-pyranoside, in the LPS frorn Pseudomonas cepacia serotypes B and E, and as a-furanoside, in the cell-wall antigen from Eubacterium saburreum L 452 and the O-antigens from different strains of Psuedomonas syrin-gae The a-furanoside, as in 3, has a cis relationship between the aglycon and OH-2. The corresponding P form has not yet been found. 6-Deoxy-o-and -L-talose are components of the extracellular polysaccharides from some strains of Butyrivibrio fibrisolvens and of the LPS from some strains of E. coli respectively. 

For example, it was possible to demonstrate formation of the modified polysaccharides of S. anatum in which a D-galactose residue is replaced by D-fucose, D-gluc-ose, D-talose, or 4-deoxy-D-xylo-hexose residues. 3-Deoxy-D-arabino-hexose or P-glucose residues may substitute for a P-mannose residue. 

Forsberg, L.S., Bhat, U.R., Carlson, R.W. Structural characterization of the O-antigenic polysaccharide of the lipopolysaccharide from Rhizobium etli strain CE3. A unique O-acetylated gly-can of discrete size, containing 3-0-methyl-6-deoxy-L-talose and 2,3,4-tri-O-methyl-L-fucose. J Biol Chem 275 (2000) 18851-18863. 

Talose, mutarotation of, 23 —, 5-acetamido-5,6-dideoxy-D-, 176 —, 5-acetamido-5,6-dideoxy-L-, 176 Taxonomy, fungal, polysaccharides as aids in, 414 Temperature... 

Other examples of the presence of this sugar are the LPSs from Rhizobium loti, which contain mainly 6-deoxytalose with small amounts of the 2-O-methyl derivative.181 The O-specific polysaccharide chain of Proteus penneri LPS also contains 6-deoxy-L-talose, together with another rarely occurring sugar, 2,3-diacetamido-2,3,6-trideoxy-L-mannose.182... 

D-Fucose, in the furanose or pyranose form, has been identified in bacteria. Actinobacillus actinomycetemcomitans strains, of all serotypes, commonly produce polysaccharide antigens consisting of 6-deoxyhexoses. In fact, the serotype b-specific polysaccharide antigen from A. actinomycetemcomitans Y4 consists of the following disaccharide repeating-unit -3)-a-D-Fuc/4 I 2)-a-i.-Rha/u( I. l92 On the other hand, serotype a consists solely of 6-deoxy-D-talose and serotype c is a polysaccharide of the l enantiomer.175... 

B. Jann, A. Shashkov, V. Torgov, H. Kochanowski, G. Seltmann, and K. Jann, NMR investigation of the 6-deoxy-L-talose-contaming 045, 045-related (045rel), and 066 polysaccharides of Escherichia coli, Carbohydr Res., 278 (1995) 155-165. 

N-Ac 2-Acetamido-2,6-dideoxy-L-talose CgHisNO 205.21 Component of the capsular polysaccharide of Alteromoruis nigrifaciens. 

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