한국인의 교정환자로부터 분리한 Streptococcus mutans의 16S rDNA 핵산염기서열의 분석

Abstract

The 45 strains of Streptococcus mutans were isolated from the dental plaque of 44 Korean orthodontic patients using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method based on dextranase gene. The aim of this study was to confirm the identification of the 45 clinical isolates as to the Streptococcus mutans strain using the 16S ribosomal RNA coding gene (16S rDNA), which was amplified from the each of the clinical isolates by the universal primers for bacteria using PCR. The amplicons were directly ligated with the pGEM-T easy vector. The insert DNA was sequenced using the dideoxy chain termination method as well as the 16S rDNA cloning and sequencing method. The 16S rDNAs were amplified from the each of the clinical isolates by the universal primers for bacteria using PCR. The amplicons were directly ligated with the pGEM-T easy vector. The insert DNA was sequenced using the dideoxy chain termination method. These results showed that the similarity of the nucleotide sequences from all the clinical isolates was > 99% compared with that from S. mutans ATCC 25175^(T). These results suggest that the clinical isolates identified as S. mutans by the PCR-RFLP based dextranase gene were correct. Overall, the clinical isolates of S. mutans might be useful in determining the Korean representative strain of S. mutans as well as being helpful in the development of a dental caries vaccine instead of the type strain isolated from a Westerner.