||Streptococcus mutans 6715 produces glucosyltransferase (EC 188.8.131.52) that catalyzes glucan formation from sucrose. however, the precise mechanism of glucan formation remains unknown. The number of enzyme proteins responsible for the synthesis of soluble and insoluble glucans, as well as the product-precursor relationship between the different glucan molecules, was the question that was asked in this current work. The enzyme from S. mutans was purified to near homogeniety using dextran affinity chromatography. Confirmation of the enzyme purity was obtained by polyacrylamide gel electrophoresis. Growth parameters of S. mutans 6715 were nearly identical when grown in either synthetic or complex media. Enzymatic properties of glucosyltransferase from either of these cultures were the same. Analysis of the kinetics of the enzymatic reaction using sucrose as substrate indicated that a product-precursor relationship between the soluble and insoluble glucan might exist.