Journal article
Inactivation of the gbpA Gene of Streptococcus mutans Alters Structural and Functional Aspects of Plaque Biofilm Which Are Compensated by Recombination of the gtfB and gtfC Genes
Infection and immunity, Vol.67(8), pp.3909-3914
08/1999
DOI: 10.1128/IAI.67.8.3909-3914.1999
PMCID: PMC96671
PMID: 10417155
Abstract
Inactivation of the
gbpA
gene of
Streptococcus mutans
increases virulence in a gnotobiotic rat model and also promotes in vivo accumulation of organisms in which
gtfB
and
gtfC
have recombined to reduce virulence (K. R. O. Hazlett, S. M. Michalek, and J. A. Banas, Infect. Immun. 66:2180–2185, 1998). These changes in virulence were hypothesized to result from changes in plaque structure. We have utilized an in vitro plaque model to test the hypothesis that the absence of GbpA alters
S. mutans
plaque structure and that the presence of
gtfBC
recombinant organisms within a
gbpA
background restores a wild-type (wt)-like plaque structure. When grown in the presence of sucrose within hydroxyapatite-coated wells, the wt
S. mutans
plaque consisted primarily of large aggregates which did not completely coat the hydroxyapatite surface, whereas the
gbpA
mutant plaque consisted of a uniform layer of smaller aggregates which almost entirely coated the hydroxyapatite. If 25% of the
gbpA
mutants used as inoculum were also
gtfBC
recombinants (
gbpA
/25%
gtfBC
), a wt-like plaque was formed. These changes in plaque structure correlated with differences in susceptibility to ampicillin;
gbpA
plaque organisms were more susceptible than organisms in either the wt or
gbpA
/25%
gtfBC
plaques. These data allow the conclusion that GbpA contributes to
S. mutans
plaque biofilm development. Since the changes in plaque structure detailed in this report correlate well with previously observed changes in virulence, it seems likely that
S. mutans
biofilm structure influences virulence. A potential model for this influence, which can account for the
gtfBC
recombination compensating
gbpA
inactivation, is that the ratio of glucan to glucan-binding protein is a critical factor in plaque development.
Details
- Title: Subtitle
- Inactivation of the gbpA Gene of Streptococcus mutans Alters Structural and Functional Aspects of Plaque Biofilm Which Are Compensated by Recombination of the gtfB and gtfC Genes
- Creators
- Karsten R. O Hazlett - Department of Microbiology, Immunology, and Molecular Genetics, Albany Medical College, Albany, New York 12208Joseph E Mazurkiewicz - 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.67(8), pp.3909-3914
- Publisher
- American Society for Microbiology
- DOI
- 10.1128/IAI.67.8.3909-3914.1999
- PMID
- 10417155
- PMCID
- PMC96671
- ISSN
- 0019-9567
- eISSN
- 1098-5522
- Language
- English
- Date published
- 08/1999
- Academic Unit
- Pediatric Dentistry; Dental Research
- Record Identifier
- 9984065712902771
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