Purification and characterization of a glycosyltransferase complex from the culture broth of Streptococcus mutans FA1

Immunological relationships between glucosyltransferases synthesizing insoluble glucan from Streptococcus cricetus, Streptococcus sobrinus and Streptococcus downei

“…Tsumori et al, 1983b;Koga et al, 1983;McCabe, 1985;Mukasa, 1986). In Streptococcus rattus (mutans group serotype 6) and Streptococcus mutans (mutans group serotypes c, e andf), adherent insoluble polysaccharide is synthesized cooperatively by two GTFs; GTF-I, which synthesizes an insoluble glucan, and GTF-S, which synthesizes a soluble glucan ; and probably fructosyltransferases, which synthesize an inulin-type fructan (Scales et al, 1975;Mukasa et al, 1982bMukasa et al, , 1985Mukasa et al, , 1989Kenny & Cole, 1983;Mukasa, 1986;Shimamura et al, 1987;Kumada et al, 1987;Tsumori et al, 1989).…”

Effects of Exogenous Insoluble Glucan Primer on Insoluble Glucan Synthesis by Streptococcus mutans

“…This dearth of knowledge may be due to the complexity of GTase in that it exists as highmolecular-weight complexes. [5][6][7][8][9] The synthesis of WIG has been shown to be affected by various factors. In this regard exogenous dextran has been reported to inhibit WIG formation5,10,11 and to stimulate WSG synthesis.6,12,13 Also, a recent study showed that high concentrations of salts not only stimulated WIG formation, but also shifted the nature of the product from WSG to WIG.14 In this paper, we wish to present evidence that the WIG produced by S. mutans does not affect the reaction rate of WIG formation, but causes the disappearance of a lag period under certain conditions.…”

Purification, surfactant stabilization, molecular weight studies, and divalent metal ion kinetics of dextransucrase from Leuconostoc mesenteroides NRRL B-512F

“…Unlike other dextransucrases successfully purified on DEAE-cellulose [150,158,186,299], dextransucrase from L. mesenteroides B-512F binds so tightly to this material that yields are normally very low [286]. In this laboratory, it was found that over a narrow range of conditions, DEAE-cellulose gave high yields and an excellent purification.…”

“…For example, glucansucrase aggregates of 0.5-50 MDa have been found for S. mutans 6715 [255]. The aggregation is frequently too high to allow penetration into chromatographic and electrophoretic media [44,98,286,299,357]. The aggregation is mediated by glucan [116,200,286], but also occurs in its absence [116,201,286,301].…”

“…These purified preparations are rarely if ever carbohydrate-free, however[52,127,128,133,150,239,255,310], although carbohydrate is not always detected[226]. Carbohydrate con tents (considered as weight ratio to protein) from 1%[310] (with 3.8% overall activity yield) to 38%[117] have been reported for purified dextransucrase from S. nutans 6715, while in this laboratory, extensive purification of this enzyme gave a preparation still containing 6% carbo hydrate[68].Compared to L, aesenteroides B-512F, strains of Streptococcus pro duce low levels of enzyme: frequently 0.1-0.2 U/ml culture[44,97,299,311], rarely more[150,311], and often far less[51,179,200,229, 315,341]. The specific activities of the purified glucansucrases[52,127,239,255] are low, high values being in the neighborhood of 50 U/mg As described under the heading "Organism" in Materials and Methods, cultures from the original lyophils of L. aesenteroides NRRL B-512F produced very little enzyme, as low as 0.02 U/ml in the culture superna tant.…”