Polysaccharides of bacteria

Antimicrobial defenses in most plants, on the other hand, have been shown to result from a post-challenge response of the plant elicited by the pathogen through products associated with the invading organism. Such products are extra-cellular polysaccharides of bacteria, or the 3-qlucans of Phytophthora mycellial walls (2). 

N. K. Kochetkov, B. A. Dmitriev, and L. V. Backinowsky, New sugars from antigenic lipo-polysaccharides of bacteria Identification and synthesis of 3-0-[(R)-l-carboxyethyl]-L- rham-nose, an acidic component of Shiqella dysenteriae type 5 lipopolysaccharide, Carbohydr. Res., 51 (1976) 229-237. 

Attachment of bacteria. At low ionic strength of the medium — as in many freshwaters — bacteria-surface interactions are controlled by the effects of van der Waals attraction and electrostatic repulsion. At high ionic strength — as in seawater — steric interactions between the outer cell surface macromolecules and the substratum gain in importance (van Loosdrecht et al., 1989 Rijnaarts etal., 1999). Additionally, flagellar and twitching motility of bacteria was found to be essential in the process of attachment by bacteria onto surfaces (Pratt and Kolter, 1998 O Toole and Kolter, 1998). It seems that extracellular polysaccharides of bacteria are not involved in the adhesion process itself. However, bacterial extracellular polysaccharides are necessary for the development of a biofilm and for the formation of microcolonies (Allison and Sutherland, 1987 Hoyle et al., 1993). 

Bastin, D.A., Brown, P.K., Haase, A., Stevenson, G., Reeves, RR. Repeat unit polysaccharides of bacteria a model for polymerisation resembling that of ribosomes and fatty acid synthetase, with a novel mechanism for determining chain length. Mol Microbiol 7 (1993) 725-734. 

Knirel, Y.A., Kocharova, N.A., Bystrova, O.A., Katzenellenbogen, E., Gamian, A. Structures and Serology of the O-Specific Polysaccharides of Bacteria of the Genus Citrobacter. Arch Immunol Ther Exp 50 (2002) 379-391. 

Polysaccharides of Bacteria, Frequently Found in Human Flora,... 

Capsular polysaccharide of bacteria is one of the significant targets for development of vaccines [128]. For example, Haemophilus influenza type B (Hib) vaccine, made of a polysaccharide-protein conjugate, is now used worldwide as a highly effective therapy [129]. Verez-... 

Later, a more detailed investigation was performed by Karl Meyer, who summarized the results as follows [9] "From the vitreous humor of cattle eyes a polysaccharide acid of high molecular mass has been obtained... As constituents there have been recognized a uronic acid, an amino sugar... It appears to be a substance unique in higher animals, and may be best compared with some of the specific polysaccharides of bacteria... We propose, for convenience, the name "hyaluronic acid", from hyaloid (vitreous) + uronic acid". 

Y. A. Knirel, A. S. Shashkov, M. A. Soldatkina, N. A. Paramonov, and I. I. Zakharova, Antigenic polysaccharides of bacteria 32. The structure of O-specific polysaccharide chains of Pseudomonas cepacia serotype B and E lipopolysaccharides containing D-fucose, Bioorg. Khim., 14 (1988) 1208-1213. 

Mitchell, R. and Nevo, Z., 1964. Decomposition of structural polysaccharides of bacteria by marine microorganisms. Nature, 205 1007—1008. 

Xanthan gum [11138-66-2] is an anionic heteropolysaccharide produced by several species of bacteria in the genus Aanthomonas A. campestris NRRL B-1459 produces the biopolymer with the most desirable physical properties and is used for commercial production of xanthan gum (see Gums). This strain was identified in the 1950s as part of a program to develop microbial polysaccharides derived from fermentations utilizing com sugar (333,334). The primary... 

The above chemicals can be obtained by fermentation (qv) of other sugars. However, some compounds require sucrose as a unique feedstock. Examples are the polysaccharides dextran, alteman, andlevan, which are produced by specific strains of bacteria (48,54—56). Dextrans are used to make chromatographic separation media, and sulfated dextran derivatives are used as plasma extenders (41). Levans show promise as sweetness potentiators and, along with alteman, have potential as food thickeners and bulking agents in reduced-caloric foods (55,56) (see Carbohydrates). 

Fluvial biofilms (also known as phytobenthos or periphyton) are attached communities consisting of bacteria, algae and fungi embedded within a polysaccharide matrix [20]. In rivers, these communities are the first to interact with... 

Treatment of an extracellular polysaccharide of Rhizobium japonicum (an important factor for nitrogen-fixing symbiosis between bacteria and soybeans) with liquid HF (—40°, 30 min) gave mono- and oligo-saccharides involving 0- -D-glucopyranosyl-( 1 - 3)-C>-(4-0-acetyl-a-D-galactopyrano-syluronic acid)-(l— 3)-D-mannose and its 1-fluoride. 

Two extracellular D-fructans, (2- 6)-linked S-D-fructofuranan or levan and the less common corresponding (2 l)-linked polysaccharide, of the inulin type, are elaborated by different bacteria. These polysaccharides are formed from sucrose by the action of sucrose fructosyltransferases. Terminal )S-D-fructofuranosyl groups are present in some bacterial heteropolysacchar-... 

Polysaccharides. Many strains of bacteria produce succinoglycan (1). The Rhizobia, particularly, grow very slowly, and the rate of polymer production is low. Much effort was spent obtaining a strain which produced succinoglycan at a high rate and of good quality (2.3). An organism was selected and a fermentation process developed at laboratory scale. The process has been scaled up successfully and operated at 220 cubic metre scale. 

Chemical analyses of capsular material from a number of bacteria show wide differences in composition. For this reason it is impossible to make statements which apply to all bacteria. In some organisms the capsular material appears to be a glycoprotein in others, a protein-polysaccharide complex in still others, a polysaccharide framework with the spaces filled in by a larger amount of glutamyl polypeptide. 

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