Abstract
A mutant of Streptococcus mutans GS-5 has been isolated as a smooth colonial variant on mitis salivarius agar. This mutant, designated SNG-1, adheres to glass surfaces as well as the parental organism when grown in the presence of sucrose. However, in contrast to the parental organism, glucose-grown cultures of the mutant did not adhere to smooth surfaces when incubated with sucrose under nongrowing conditions. The inability of the mutant organism to adhere to glass surfaces under the latter condition was a result to markedly reduced levels of mutant cell-associated glucosyltransferase activity. In addition, the extracellular activity of the mutant was also severely depressed relative to the parental activity. The reduced levels of mutant enzyme activity appear to be a result of a mutation in a structural gene coding for glucosyltransferase activity since (i) mutant glucosyltransferase activity is much less resistant to heat inactivation compared to the parental enzymes and (ii) the migration patterns of the mutant and parental enzymes differ on polyacrylamide gels and after isoelectric focusing on polyacrylamide gels. However, the kinetic properties of the mutant enzymes are similar to those of the comparable parental activities in terms of pH and temperature optima and Km values for sucrose. The mutant enzyme responsible for soluble glucan synthesis has been purified approximately 300-fold. These results are discussed in terms of the mechanism of glucan synthesis by S. mutans.
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Selected References
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- Ceska M., Granath K., Norrman B., Guggenheim B. Structural and enzymatic studies on glucans synthesized with glucosyltransferases of some strains of oral streptococci. Acta Chem Scand. 1972;26(6):2223–2230. doi: 10.3891/acta.chem.scand.26-2223. [DOI] [PubMed] [Google Scholar]
- Chludzinski A. M., Germaine G. R., Schachtele C. F. Purification and properties of dextransucrase from Streptococcus mutans. J Bacteriol. 1974 Apr;118(1):1–7. doi: 10.1128/jb.118.1.1-7.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DAVIS B. J. DISC ELECTROPHORESIS. II. METHOD AND APPLICATION TO HUMAN SERUM PROTEINS. Ann N Y Acad Sci. 1964 Dec 28;121:404–427. doi: 10.1111/j.1749-6632.1964.tb14213.x. [DOI] [PubMed] [Google Scholar]
- Ebisu S., Misaki A., Kato K., Kotani S. The structure of water-insoluble glucans of cariogenic Streptococcus mutans, formed in the absence and presence of dextranase. Carbohydr Res. 1974 Dec;38:374–381. doi: 10.1016/s0008-6215(00)82375-7. [DOI] [PubMed] [Google Scholar]
- Fukui K., Fukui Y., Moriyama T. Purification and properties of dextransucrase and invertase from Streptococcus mutans. J Bacteriol. 1974 Jun;118(3):796–804. doi: 10.1128/jb.118.3.796-804.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Guggenheim B., Newbrun E. Extracellular glucosyltransferase activity of an HS strain of Streptococcus mutans. Helv Odontol Acta. 1969 Oct;13(2):84–97. [PubMed] [Google Scholar]
- Johnson M. C., Bozzola J. J., Shechmeister I. L. Morphological study of Streptococcus mutans and two extracellular polysaccharide mutants. J Bacteriol. 1974 Apr;118(1):304–311. doi: 10.1128/jb.118.1.304-311.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuramitsu H. K. Adherence of Streptococcus mutans to dextran synthesized in the presence of extracellular dextransucrase. Infect Immun. 1974 Apr;9(4):764–765. doi: 10.1128/iai.9.4.764-765.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuramitsu H. K. Characterization of cell-associated dextransucrase activity from glucose-grown cells of Streptococcus mutans. Infect Immun. 1974 Jul;10(1):227–235. doi: 10.1128/iai.10.1.227-235.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuramitsu H. K. Characterization of extracellular glucosyltransferase activity of Steptococcus mutans. Infect Immun. 1975 Oct;12(4):738–749. doi: 10.1128/iai.12.4.738-749.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuramitsu H. K. Characterization of invertase activity from cariogenic Streptococcus mutans. J Bacteriol. 1973 Sep;115(3):1003–1010. doi: 10.1128/jb.115.3.1003-1010.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- McCabe M. M., Smith E. E. Origin of the cell-associated dextransucrase of Streptococcus mutans. Infect Immun. 1973 Jun;7(6):829–838. doi: 10.1128/iai.7.6.829-838.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mukasa H., Slade H. D. Mechanism of adherence of Streptococcus mutans to smooth surfaces. I. Roles of insoluble dextran-levan synthetase enzymes and cell wall polysaccharide antigen in plaque formation. Infect Immun. 1973 Oct;8(4):555–562. doi: 10.1128/iai.8.4.555-562.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mukasa H., Slade H. D. Mechanism of the Adherence of Streptococcus mutans to Smooth Surfaces III. Purification and Properties of the Enzyme Complex Responsible for Adherence. Infect Immun. 1974 Nov;10(5):1135–1145. doi: 10.1128/iai.10.5.1135-1145.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nalbandian J., Freedman M. L., Tanzer J. M., Lovelace S. M. Ultrastructure of Mutants of Streptococcus mutans with Reference to Agglutination, Adhesion, and Extracellular Polysaccharide. Infect Immun. 1974 Nov;10(5):1170–1179. doi: 10.1128/iai.10.5.1170-1179.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Olson G. A., Bleiweis A. S., Small P. A., Jr Adherence inhibition of Streptococcus mutans: an assay reflecting a possible role of antibody in dental caries prophylaxis. Infect Immun. 1972 Apr;5(4):419–427. doi: 10.1128/iai.5.4.419-427.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Scherp H. W. Dental caries: prospects for prevention. Science. 1971 Sep 24;173(4003):1199–1205. doi: 10.1126/science.173.4003.1199. [DOI] [PubMed] [Google Scholar]
- de Stoppelaar J. D., König K. G., Plasschaert A. J., van der Hoeven J. S. Decreased cariogenicity of a mutant of Streptococcus mutans. Arch Oral Biol. 1971 Aug;16(8):971–975. doi: 10.1016/0003-9969(71)90186-5. [DOI] [PubMed] [Google Scholar]
