Glucans, synthesis

SAKANAKA s, SATO T, KIM M and YAMAMOTO T (1990) Inhibitory effects of green tea polyphenols on glucan synthesis and cellular adherence of cariogenic streptococci , Agric Biol... 

Murata M, Nakajima Y and Homma S (1995) Inhibition of cariogenic glucan synthesis by dark beer. Lebensm Wiss Technol 28, 201-207. 

The enzymes involved are nucleoside diphosphohexosetransferases, probably GDP-D-mannosyltransferase (EC 2.4.1.32) and UDP-D-galactosyl-transferase. For a structurally related polymer, (1 - 6)-a-D-xylosyl-(l - 4)-/3-D-glucan, synthesis was shown to involve concurrent incorporation of D-xylose and D-glucose, and not substitution by D-xylose of a preformed (1 - 4)-/3-D-glucan chain.34 The insolubility of (1 - 4)-/3-D-glucan and man-nan would make the latter mechanism unlikely. 

Results of later studies by Delmer and coworkers189,179 provided some support for this hypothesis. Thus, it was shown that re-establishment of a transmembrane, electrical potential (positive-inside) across vesicles isolated from cotton fibers resulted in a 4-12-fold stimulation of /3-D-glucan synthesis from UDP-glucose (see Fig. 5). Such a potential was established by the addition of K+ in the presence of an imper-... 

Moreno, S., Cardini, C. E., and Tandecarz, J. S. 1986. a-Glucan synthesis on a protein primer. A reconstituted system for the formation of protein-bound a-glucan. Eur. J. Biochem. 162, 609-614. 

Sivak. M. N., 1992. (1— 4)-a-D-Glucan synthesis by a chloroplastic phosphorylase isolated from spinach leaves is independent of added primer. Carbohyd. Res. 227, 241-255. 

The enzymatic reactions involved in starch synthesis in higher plants and algae and in glycogen synthesis in cyanobacteria are reviewed in this article. Regulation of a-1,4 and a-1,6 glucan synthesis at the enzymic level is discussed, and mutants that cause specific enzymatic deficiencies that affect starch structure are also reviewed. Recent reviews on starch synthesis have been published and are noted (1-6). 

Takahashi, Y, Ogawa, T, Glucan synthesis. 6. Total synthesis of cyclomaltohexaose, Carbohydr. Res., 164, 277-296, 1987. 

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