Journal of Dental Research, Vol 55, 77-84, Copyright © 1976 by International & American Associations for Dental Research Online Journals
Acrylamide gel electrophoretic studies of extracellular sucrose-metabolizing enzymes of Streptococcus mutans
R. M. Osborne, B. L. Lamberts, T. S. Meyer and A. H. Roush
This study explored the use of acrylamide gel electrophoretic methods to
determine the numbers and types of extracellular sucrose-metabolizing
enzymes produced by particular strains of S mutans. Strains HS-6, SL-1,
FA-1, and NCTC 10449 were cultured in a chemically defined medium and the
extracellular proteins elaborated by the organisms were isolated and
subjected to acrylamide gel electrophoresis. Patterns of protein components
and sucrose-metabolizing enzymes were then delineated. Three types of
sucrose-metabolizing enzymes were observed. One type was involved in the
synthesis of polysaccharides that were insolubilized in the gels. Another
type was involved in the synthesis of water-soluble polysaccharides. A
third type was involved in the splitting of sucrose into reducing sugars
without polysaccharide synthesis. Each pattern was distinctive with regard
to the numbers, proportions, and types of enzyme components present and
their migratory characteristics. From two to at least six components were
observed amont the enzyme activity patterns per strain. Extracellular
protein patterns showed from 12 to 20 components per strain. Comparative
data on growth in the chemically defined medium and Todd-Hewitt broth were
also presented. Better growth levels were obtained in all instances with
the chemically defined medium over comparable periods of time.
