Evaluation of genotypic diversity of Streptococcus mutans using distinct arbitrary primers

Abstract

Streptococcus mutans has been considered one of the main etiological agents of dental caries and the genotypic diversity rather than its salivary counts may be considered as a virulence factor of this bacterium. For genotyping with polymerase chain reaction (PCR) with arbitrary primers, several primers have been used in order to improve complexity and specificity of amplicon patterns. Thus, the aim of this study was to evaluate the degree of agreement of genotypic identification among AP-PCR reactions performed with 5 distinct arbitrary primers of S. mutans isolated from saliva. Stimulated saliva was collected from 11 adult volunteers for isolation of S. mutans, and a total of 88 isolates were genotyped with arbitrary primers OPA 02, 03, 05, 13 and 18. Fourteen distinct genotypes were identified in the saliva samples. Most volunteers (9 out of 11) presented only one genotype. The results of the present study suggest that primers OPA 02, 03, 05 and 13 were suitable for genotypic identification of S. mutans isolates of saliva from adult volunteers.

Mutans streptococci genetic strains in children with severe early childhood caries: follow-up study at one-year post-dental rehabilitation therapy

“…The acidogenic MS group, including S. mutans and Streptococcus sobrinus , are among the cariogenic microorganisms that reside in the oral cavity, and represent the most predominant bacteria associated with dental caries. The oral cavity harbors distinct genotypes of S. mutans in saliva and dental plaque, with at least 52 known genotypes (3, 4). Some MS genotypes may have preferential abilities to colonize and predominate in specific oral environments (3–5).…”

Genotypic diversity and acidogenicity of Streptococcus mutans in Down syndrome children

“…After incubation, S. mutans colonies were identified and counted under stereomicroscopic visualization to determine the number of colony forming units per mL (CFU/mL). Fifteen representative colonies of S. mutans from each child were selected and frozen in BHI‐glycerol for later analysis . In order to reduce the risk of selection bias, all different morphological types from the plate were selected first and, after that, the other colonies were randomly selected.…”

“…Fifteen representative colonies of S. mutans from each child were selected and frozen in BHI-glycerol for later analysis. 21 In order to reduce the risk of selection bias, all different morphological types from the plate were selected first and, after that, the other colonies were randomly selected. A grid with 50 squares was placed underneath the plate.…”

“…The AP-PCR reaction was run in a thermocycler (TC 412, Techne, Burlington, NJ, USA) with the following conditions: for OPA 02, one 2minute cycle at 95 • C for initial denaturation, followed by 45 cycles of 30 seconds each at 94 • C for denaturation, 36 • C for 30 seconds to promote annealing, 72 • C for 1 minute for elongation, and 72 • C for 5 minutes for final elongation; for OPA 03, one 2-minute cycle at 95 • C for initial denaturation, followed by 30 cycles of 1 minute each at 94 • C for denaturation, 32 • C for 1 minute to promote annealing, 72 • C for 2 minutes for elongation, and 72 • C for 5 minutes for final elongation. 21 AP-PCR products were analyzed by 1% agarose gel electrophoresis stained with SYBR Green 1.6% at 96 V during 4 hours. A molecular weight control (250 bp) was run in three gel slots for further comparison with the generated fragments.…”

Early Childhood Caries Update

“…However, it is still unknown if genotypic diversities and phenotypic traits of S. mutans are related to different caries status or caries severity in children [38]. Regardless of caries status, the genotypic diversity of S. mutans was determined to be similar.…”