Characterization of glucosyltransferase of human saliva adsorbed onto hydroxyapatite surfaces.

Activities of glucosyltransferases (Gtf)-B, -C and -D adsorbed on the surface of saliva-coated hydroxyapatite were compared with those of Gtfs of donor whole saliva. Antiserum raised against a mixture of the three Gtfs reduced the activity of GtfB only, and had no effect on donor Gtf activities. GtfB, and not the Gtfs of the donors, was stimulated in the presence of starch hydrosylates. GtfD and GtfC activities were enhanced on the surfaces, as were the Gtf activities of donor salivas. The activities of GtfD and GtfB, but not GtfC, were stimulated by dextran. The donor Gtf activities were unaffected by dextran. Therefore, Gtf activity in pellicles has properties similar to those of GtfC.