title: Phylogenetic analyses and detection of viridans streptococci based on sequences and denaturing gradient gel electrophoresis of the rod shape-determining protein gene.
abstract: BACKGROUND
  Population analysis of viridans streptococci is important because these species are associated with dental caries, bacteremia, and subacute endocarditis, in addition to being important members of the human oral commensal microbiota.
  
  
  METHODS
  In this study, we phylogenetically analyzed the rod shape-determining protein gene (rodA), which is associated with cellular morphology, cell division, and sensitivity for antibiotics, and demonstrated that the diversity of the rodA gene is sufficient to identify viridans streptococci at the species level. Moreover, we developed a more convenient denaturing gradient gel electrophoresis (DGGE) method based on the diversity of the rodA gene (rodA-DGGE) for detecting nine dominant streptococcal species in human saliva, namely, Streptococcus sanguinis, Streptococcus oralis, Streptococcus mitis, Streptococcus parasanguinis, Streptococcus gordonii, Streptococcus vestibularis, Streptococcus salivarius, Streptococcus mutans, and Streptococcus sobrinus.
  
  
  RESULTS
  This rodA-DGGE method proved useful in detecting viridans streptococci without cultivation, isolation, and phenotypic characterization.
  
  
  CONCLUSIONS
  Analysis of the oral microbiota by rodA-DGGE offers a higher resolution than the conventional DGGE using 16S rDNA and may be an alternative in the microbial diagnosis of streptococcal infection.
authors.affiliation: Department of Pediatric Dentistry, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Ikuri
authors.initials: I
authors.lastname: Konishi
authors.forename: Tomonori
authors.initials: T
authors.lastname: Hoshino
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kondo
authors.forename: Kan
authors.initials: K
authors.lastname: Saito
authors.forename: Miyuki
authors.initials: M
authors.lastname: Nishiguchi
authors.forename: Kyoko
authors.initials: K
authors.lastname: Sato
authors.forename: Taku
authors.initials: T
authors.lastname: Fujiwara