title: Serotype classification of Streptococcus mutans and its detection outside the oral cavity.
abstract: Streptococcus mutans, generally known as a major pathogen of dental caries, is also a possible causative agent of bacteremia and infective endocarditis. S. mutans is classified into serotypes c, e, f and k based on the chemical composition of serotype-specific polysaccharides, with approximately 70-80% of strains found in the oral cavity classified as serotype c, followed by e (approximately 20%), and f and k (less than 5% each). Serotype k was recently designated as a novel serotype and shown to possess unique features, the most prominent being a defect of the glucose side chain in serotype-specific rhamnose-glucose polymers, which is related to a higher incidence of detection in cardiovascular specimens, owing to phagocytosis resistance. Molecular analyses of cardiovascular specimens showed a high detection frequency for S. mutans DNA, among which the detection rate for serotype k was quite high. These findings suggest that serotype k S. mutans possibly has a high level of virulence for systemic diseases.
authors.affiliation: Department of Pediatric Dentistry, Division of Oral Infections & Disease Control, Osaka University Graduate School of Dentistry, 1-8 Yamada-oka, Suita, Osaka 565-0871, Japan. nakano@dent.osaka-u.ac.jp
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nakano
authors.forename: Takashi
authors.initials: T
authors.lastname: Ooshima
mesh_terms: D016470:Bacteremia / Q000382:microbiology; D004697:Endocarditis, Bacterial / Q000382:microbiology; D006801:Humans; D011135:Polysaccharides, Bacterial / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D012703:Serotyping / Q000379:methods*; D013290:Streptococcal Infections / Q000382:microbiology*; D013295:Streptococcus mutans / Q000737:chemistry / Q000145:classification* / Q000302:isolation & purification*
chemical_list: D011135:Polysaccharides, Bacterial