Detection of Streptococcus sobrinus by polymerase chain reaction / 实用口腔医学杂志

Objective: To develop a PCR method for detecting S treptococcus sobrinus (S.s) in conventional culture. Method: A pair of specific primers were designed from the dexA gene of S.s , the genome DNA of 12 strains of Mutans Streptococci (8 serotypes from a ～h) and 23 species of the bacteria which were commonly found in oral cavity wer e tested by PCR amplification, the PCR products were identified by electrophore sis. Result: Only S.s of serotype d and g could produ ce 277 bp DNA fragments, and the PCR method could detect less than 1 000 copies of S.s. Conclusion: PCR method is specific and sen sitive in the detection of S.s.