Chromosomal Deletions in Melibiose-negative Isolates of Streptococcus mutans

Abstract

Isolates from a collection of phenotypically melibiose-negative (Mel-) Streptococcus mutans from widely-scattered geographical locations were examined and found to lack the activities of the enzymes α-galactosidase and a-glucosidase, in addition to being unable to transport melibiose. Cloned fragments of S. mutans DNA from the region of the chromosome carrying the genes for a-galactosidase (aga), sucrose phosphorylase (gtfA), and dextranglucosidase (dexB), as well as the genes encoding components of the binding-protein-dependent uptake system for raffinose and melibiose, were used in hybridization studies for investigation of the genetic basis of the Mel- phenotype. A region of at least 12 kilobases, containing all the above genes, was found to be deleted from the chromosome of the Mel- strains. It appears that this region of the chromosome is not essential for survival of S. mutans in the oral cavity. The reason for the frequent occurrence of deletions, as opposed to other forms of mutational events, is unknown.

Get full access to this article

View all access options for this article.

References

Aduse-Opoku, J. ; Gilpin, M.L. ; and Russell, R.R.B. (1989): Genetic and Antigenic Comparison of Streptococcus mutans Fructosyltransferase and Glucan-binding Protein, FEMS Microbiol Lett 59:279-282.

Aduse-Opoku, J. ; Tao, L. ; Ferretti, J.J. ; and Russell, R.R.B. (1991): Biochemical and Genetic Analysis of Streptococcus mutans a-galactosidase, J Gen Microbiol 137:757-764.

Ames, G.F.L. (1988): Structure and Mechanism of Bacterial Periplasmic Transport Systems, Bioenerget Biomemb 20:1-18.

Beighton, D. ; Russell, R.R.B. ; and Hayday, H. (1981): The Isolation and Characterization of Streptococcus mutans Serotype h from Dental Plaque of Monkeys (Macaca fascicularis), J Gen Microbiol 124:271-279.

Beighton, D. ; Russell, R.R.B. ; and Whiley, R.A. (1991): A Simple Biochemical Scheme for the Differentiation of Streptococcus mutans and Streptococcus sobrinus, Caries Res 25:174-178.

Edwardsson, S. (1968): Characteristics of Caries-inducing Human Streptococci Resembling Streptococcus mutans, Arch Oral Biol 13 :637-646.

Ferretti, J.J. ; Huang, T.-T. ; and Russell, R.R.B. (1988): Sequence Analysis of the Glucosyltransferase A Gene (gtfA) from Streptococcus mutans Ingbritt, Infect Immun 56:1585-1588.

Gold, O.G. ; Jordan, H.V. ; and Van Houte, J. (1973): A Selective Medium for Streptococcus mutans, Arch Oral Biol 18:1357-1364.

Hamada, S. ; Masuda, N. ; and Kotani, S. (1980): Isolation and Serotyping of Streptococcus mutans from Teeth and Faeces of Children, J Clin Microbiol 11:314-318.

10.

Hamada, S. and Slade, H.D. (1980): Biology, Immunology, and Cariogenicity of Streptococcus mutans, Microbiol Rev 44:331-384.

11.

Krasse, B. (1966): Human Streptococci and Experimental Caries in Hamsters, Arch Oral Biol 11:429-436.

12.

Krawiec, S. and Riley, M. (1990): Chromosome Organisation, Microbiol Rev 54:502-539.

13.

Loesche, W.J. (1986): Role of Streptococcus mutans in Human Dental Decay , Microbiol Rev 50:355-380.

14.

Maniatis, T. ; Fritsch, E.F. ; and Sambrook, J. (1982): Molecular Cloning: A Laboratory Manual, Cold Spring Harbor, NY: Cold Spring Harbor Laboratory .

15.

May, G. ; Dersch, P. ; Haardt, M. ; Middendorf, A. ; and Bremer, E. (1990): The osmZ (bg1Y) Gene Encodes the DNA-binding Protein H-NS (Hla), a Component of the Escherichia coli K12 Nucleoid, Molec Gen Genet 224:81-90.

16.

Mollet, B. and Delley, M. (1990): Spontaneous Deletion Formation within the α-Galactosidase Gene of Lactobacillus bulgaricus, J Bacteriol 172:5670-5676.

17.

Russell, R.R.B. (1979): Comparison of Oral Streptococcus mutans AHT with Strains of Serotypes a and g by Biochemical and Electrophoretic Methods, Arch Oral Biol 24:617-619.

18.

Russell, R.R.B. ; Aduse-Opoku, J. ; Tao, L. ; and Ferretti, J.J. (1991): A Binding Protein-Dependent Transport System in Streptococcus mutans. In: Genetics and Molecular Biology of Streptococci, Lactococci and Enterococci, G. Dunny , P. Cleary , and L. McKay , Eds., Washington, DC: American Society for Microbiology, pp. 244-247.

19.

Russell, R.R.B. and Ferretti, J.J. (1990): Nucleotide Sequence of the Dextran Glucosidase (dexB) Gene of Streptococcus mutans, J Gen Microbiol 136:803-810.

20.

Russell, R.R.B. and Ivic, A. (1989): Use of DNA Probes for the Identification of Oral Streptococci, Caries Res 23:111.

21.

Shklair, I.L. and Keene, H.J. (1974): A Biochemical Scheme for the Separation of the Five Varieties of Streptococcus mutans, Arch Oral Biol 9:1079-1081.

22.

Sims, W. (1972): The Concept of Immunity in Dental Caries, Oral Surg Oral Med Oral Pathol 34:69-86.