Journal article
Inactivation of the gbpA Gene of Streptococcus mutans Increases Virulence and Promotes In Vivo Accumulation of Recombinations between the Glucosyltransferase B and C Genes
Infection and immunity, Vol.66(5), pp.2180-2185
05/1998
DOI: 10.1128/iai.66.5.2180-2185.1998
PMCID: PMC108179
PMID: 9573105
Abstract
Glucan-binding protein A (GbpA) of
Streptococcus mutans
has been hypothesized to promote sucrose-dependent adherence and the cohesiveness of plaque and therefore to contribute to caries formation. We have analyzed the adherence properties and virulence of isogenic
gbpA
mutants relative to those of wild-type
S. mutans
. Contrary to expectations, the
gbpA
mutant strains displayed enhanced sucrose-dependent adherence in vitro and enhanced cariogenicity in vivo. In vitro,
S. mutans
was grown in the presence of [
3
H]thymidine and sucrose within glass vials. When grown with constant rotation, significantly higher levels of
gbpA
mutant organisms than of wild type remained adherent to the vial walls. Postgrowth vortexing of rotated cultures significantly decreased adherence of wild-type organisms, whereas the adherence of
gbpA
mutant organisms was unaffected. In the gnotobiotic rat model, the
gbpA
mutant strain was hypercariogenic though the colonization levels were not significantly different from those of the wild type. The
gbpA
mutant strain became enriched in vivo with organisms that had undergone a recombination involving the
gtfB
and
gtfC
genes. The incidence of
gtfBC
recombinant organisms increased as a function of dietary sucrose availability and was inversely correlated with caries development. We propose that the absence of GbpA elevates the cariogenic potential of
S. mutans
by altering the structure of plaque. However, the hypercariogenic plaque generated by
gbpA
mutant organisms may be suboptimal for
S. mutans
, leading to the accumulation of
gtfBC
recombinants whose reduced glucosyltransferase activity restores a less cariogenic plaque structure.
Details
- Title: Subtitle
- Inactivation of the gbpA Gene of Streptococcus mutans Increases Virulence and Promotes In Vivo Accumulation of Recombinations between the Glucosyltransferase B and C Genes
- Creators
- Karsten R. O Hazlett - Department of Microbiology, Immunology, and Molecular Genetics, Albany Medical College, Albany, New York 12208Suzanne M Michalek - Department of Microbiology, Immunology, and Molecular Genetics, Albany Medical College, Albany, New York 12208Jeffrey A Banas - Department of Microbiology, Immunology, and Molecular Genetics, Albany Medical College, Albany, New York 12208
- Resource Type
- Journal article
- Publication Details
- Infection and immunity, Vol.66(5), pp.2180-2185
- Publisher
- American Society for Microbiology
- DOI
- 10.1128/iai.66.5.2180-2185.1998
- PMID
- 9573105
- PMCID
- PMC108179
- ISSN
- 0019-9567
- eISSN
- 1098-5522
- Language
- English
- Date published
- 05/1998
- Academic Unit
- Pediatric Dentistry; Dental Research
- Record Identifier
- 9984065977702771
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