Dextran sucrase

B) alternating comb dextran (65% a-1- 6 linkages and 35% a-1- 3 branch linkages) S3mthesized by Streptococcus mutans dextran-sucrase ... 

The majority of dextrans in nature are produced extracellularly via dextran-sucrase from sucrose by several lactic acid bacteria, principally Leuconostoc and Streptococcus species [13]. Dextran is also synthesised by dextrinase of different Gluconobacter species [56]. Referring to this enzyme, fermentation of maltodextrins leads to a- —4) branched dextrans with comparatively lower Mw. However, dextransucrase from Leuconostoc mesenteroid.es NRRL B-512F has attracted most interest because of commercial use. 

Dextran-sucrase Invertase Sugar syrups Ice cream Artificial honey Candy... 

Dextran - an oi(l->6) polymer of glucose with ot(l->2), ot(l->3), and ot(l->4) branch points. Dextran is the only polysaccharide listed here that does not use activated nucleotide sugars (or derivatives) in making the polymer. The polymerization, catalyzed by the enzyme dextran sucrase, is a transglycosylation of sucrose ... 

For dextran production, 10% w/v sucrose is supplied as substrate, the incubation is conducted at 15 °C or below, in the presence of about 30 units/ml of dextran sucrase. Molecular weight of dextran produced can be controlled by sucrose concentration, enzyme concentration, and by the temperature and time used for incubatioiL... 

Dextran Sucrose. Dextrans are produced by the bacteria Leuconostoc mesenteroides from sucrose. The reaction is catalyzed by a glucotrans-ferase, which has been purified and which produces little if any free glucose.Similar enzymes appear to be present in other bacteria. The reaction catalyzed by dextran sucrase is ... 

Amylosucrase. An enzyme from the bacteria Neisseria perfiava carries out a reaction similar to that of dextran sucrase, but forms a-1-4 Unkages instead of a-1-6. The reaction is reversible, but, as in case of dextran... 

Sucrose is converted into dextrans by various species of Levconostoc or the dextran-sucrase enzymes isolated from these organisms 177), A 99% conversion of the D-glucose present in sucrose may be obtained by use of a pure enzyme. Phosphate plays no part in the synthesis, and the over-all action is not reversible ... 

Dextran is a glucan material produced by the action of the extracellular enzyme dextran sucrase on sucrose in solution and it has shown uses for flocculation in alkaline systems, such as those found in the alumina Bayer process. 

A paper has been given at a workshop on the oxidation of sucrose and isomaltulose to the 3-keto-derivatives by Agrobacterium tumefaciens, and the synthesis of oligosaccharides using dextran sucrase was described. ... 

Leuconostoc mesenteroides, Streptobacterium dextranicum, Streptococcus mutans and some other bacteria produce extracellular dextran from saccharose with the help of a-l,6-glucan D-fruc-tose-2-glucosyl transferase (dextran sucrase, EC 2.4.1.5). 

Lactobacillus. The formation of d. by the mouth flora is considered as the onset of dental caries. Biosynthesis is performed by the action of the enzyme dextran-sucrase (EC 2.4.1.5.), which acts as an exoenzyme ... 

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