Genotypic diversity and virulence traits of Streptococcus mutans in caries-free and caries-active individuals.
The present study evaluated the relationship between clonal diversity and some virulence traits of Streptococcus mutans isolated from eight caries-free and eight caries-active subjects. A total of 155 S. mutans isolates from caries-free subjects and 144 isolates from caries-active subjects were obtained from samples of saliva, dental plaque and tongue surface and identified by PCR. The isolates were submitted to arbitrarily primed (AP)-PCR (OPA-2 and OPA-13) and multilocus enzyme electrophoresis (MLEE) to establish the genotypic diversity. Production of water-insoluble glucan (WIG) (monitored by SDS-PAGE), final pH of cultures and the ability of bacterial cells to adhere to smooth glass in the presence of sucrose were measured. High and comparable abilities of MLEE and AP-PCR were found to distinguish S. mutans genotypes, using Simpson's index of discrimination (0.971 and 0.968, respectively). The results showed a significant difference (P < 0.01) in the number of genotypes when caries-free and caries-active groups were compared by both fingerprinting methods used. Final pH (P = 0.32) and the percentage of adherence to a glass surface (P = 0.62) did not show differences between the two groups; however, the intensities of WIG bands from the caries-active group were greater than those from the caries-free group (P < 0.01). In addition, WIG was positively correlated with the ability of S. mutans to adhere to a glass surface (r = 0.34, P = 0.02) from caries-active subjects. These data showed that AP-PCR analysis and MLEE are both effective methods for assessing the genetic relatedness of S. mutans. Using these techniques, it was found that there is a larger number of genotypes of S. mutans with increased ability to synthesize WIG in caries-active individuals.
Napimoga
Marcelo Henrique
MH
Department of Oral Diagnostics, Faculty of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
Kamiya
Regianne Umeko
RU
Department of Oral Diagnostics, Faculty of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
Rosa
Rosimeire Takaki
RT
Department of Oral Diagnostics, Faculty of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
Rosa
Edvaldo AntonioR
EA
Department of Oral Diagnostics, Faculty of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
Höfling
José Francisco
JF
Department of Oral Diagnostics, Faculty of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
de Oliveira Mattos-Graner
Renata
R
Department of Oral Diagnostics, Faculty of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
Gonçalves
Reginaldo Bruno
RB
Department of Oral Diagnostics, Faculty of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
D000293:Adolescent; D000328:Adult; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000032:analysis; D015373:Bacterial Typing Techniques; D003470:Culture Media / Q000737:chemistry; D016172:DNA Fingerprinting; D003731:Dental Caries / Q000382:microbiology*; D003773:Dental Plaque / Q000382:microbiology; D004798:Enzymes / Q000032:analysis; D014644:Genetic Variation; D005936:Glucans / Q000096:biosynthesis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010449:Peptide Mapping; D016133:Polymerase Chain Reaction; D012463:Saliva / Q000382:microbiology; D013295:Streptococcus mutans / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D014059:Tongue / Q000382:microbiology; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics* / Q000502:physiology
D001426:Bacterial Proteins; D003470:Culture Media; D004798:Enzymes; D005936:Glucans; D037521:Virulence Factors