Journal of Dental Research, Vol 64, 447-449, Copyright © 1985 by International & American Associations for Dental Research Online Journals
pH change in artificial dental plaque formed by glucosyltransferase and some oral bacteria during batch and continuous culture
T. Takehara, M. Itoh, N. Hanada and E. Saeki
Streptococcus mutans alone or cell-free glucosyltransferase
(G-Tase)-together with either Streptococcus sanguis, Streptococcus
salivarius, Actinomyces viscosus, or Lactobacillus casei cells-formed
artificial dental plaque that firmly adhered to glass electrodes in a
continuous culture system containing sucrose. The pH in these artificial
plaque samples decreased more than did that of the surrounding medium. In
the absence of GTase, the bacteria other than S. mutans did not form
firmly-adhering plaque on glass electrodes. The pH of the plaque formed
with GTase alone did not show the pH decrease seen when the plaque
contained bacteria, but, because it catalyzed the synthesis of glucan, it
is suggested that the glucan acts as a diffusion barrier to retard acid
loss from plaque containing acid-producing bacteria.
