Extracellular dextran hydrolase from Streptococcus mutans strain 6715.

Streptococcus mutans strain 6715 was shown to produce an extracellular dextramase with endohydrolytic alpha-(1 leads to 6)-glucan-6-glucanohydrolase activity. The enzyme degraded soluble polymers produced by some oral streptococci but did not disperse the streptococcal plaques tested. Enzyme levels in the culture supernatant were elevated in sucrose and sucrose plus glucose cultures but remained at basal levels in glucose and dextran plus glucose cultures.