title: [Rapid detection of Streptococcus mutans and streptococcus sobrinus in human saliva by nested polymerase chain reaction].
abstract: OBJECTIVE
  To establish a simple and rapid method to detect Streptococcus mutans and streptococcus sobrinus simultaneously in human saliva.
  
  
  METHODS
  Chromosomal DNA from the bacteria was obtained by the extraction method with phenol-chloroform. A nested PCR method with two sets of primers specific for portions of the glucosyltransferase genes (gtfB of S. mutans and gtfI of S. sobrinus), was optimized to detect S. mutans and S. sobrinus from standard strains, clinical strains and directly in human saliva.
  
  
  RESULTS
  The first process of nested PCR was capable of amplifying DNA fragments specific for these species from chromosomal DNA extracted from 10(5) CFU cells of standard and clinical strains, or from 1 ml clinical saliva samples containing 10(5) CFU cells of either species. a second process of nested PCR, using the first PCR product as a template with new internal primers to detect 10(3) CFU of either streptococcal species in 1ml saliva samples.
  
  
  CONCLUSIONS
  Nested PCR could detect S. mutans and S. sobrinus rapidly and simply in human saliva. This finding would be important to studies of elucidation the role of these two streptococcal species in the etiology of dental caries.
authors.affiliation: Department of Operative and Endodontics, School of Stomatology, Wuhan University, Wuhan 430079, China.
authors.forename: Hai-ping
authors.initials: HP
authors.lastname: Tian
authors.forename: Zhuan
authors.initials: Z
authors.lastname: Bian
authors.forename: Ming-wen
authors.initials: MW
authors.lastname: Fan
authors.forename: Zhi
authors.initials: Z
authors.lastname: Chen
authors.forename: Bing
authors.initials: B
authors.lastname: Fan
mesh_terms: D006801:Humans; D016133:Polymerase Chain Reaction; D012463:Saliva / Q000382:microbiology*; D013295:Streptococcus mutans / Q000235:genetics / Q000302:isolation & purification*; D016986:Streptococcus sobrinus / Q000235:genetics / Q000302:isolation & purification*