Glucosyltransferase production by Streptococcus sanguis 804 (NCTC 10904)

Abstract

Streptococcus sanguis 804 (NCTC 10904) was grown ih batch culture at constant pH. and the glucosyltransferase activity of the supernatant was assayed over a 40-h growth period. The optimum pH for enzyme production was 7.0 to 7.2. During growth of the culture, three reproducible phases of enzyme activity were observed. The polysaccharides synthesized during each of these phases were characterized as dextran-like glucans by analysis of acid hydrolysates, gas-liquid chromatography, and a specific aggregation technique. The glucans were studied further by infrared spectroscopy, enzymic degradation, and periodate oxidation. Differences in the proportions of alpha-(1 leads to 3)- and alpha-(1 leads to 6)-linkages were observed. The results suggest that glucan synthesis by S. sanguis involves a multienzyme system.