Open AccessStreptococcus mutans Clonal Variation Revealed by Multilocus Sequence Typing
Author(s) -
Kazuhitko Nakano,
Jinthana Lapirattanakul,
Ryota Nomura,
Hirotoshi Nemoto,
Satu Alaluusua,
Lisa Grönroos,
Martti Vaara,
Shigeyuki Hamada,
Takashi Ooshima,
Ichirô Nakagawa
Publication year - 2007
Publication title -
journal of clinical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.349
H-Index - 255
eISSN - 1070-633X
pISSN - 0095-1137
DOI - 10.1128/jcm.02343-06
Subject(s) - multilocus sequence typing , biology , streptococcus mutans , serotype , housekeeping gene , typing , microbiology and biotechnology , population , genetics , locus (genetics) , allele , genotype , pathogen , virology , gene , bacteria , medicine , gene expression , environmental health
Streptococcus mutans is the major pathogen of dental caries, a biofilm-dependent infectious disease, and occasionally causes infective endocarditis.S. mutans strains have been classified into four serotypes (c ,e ,f , andk ). However, little is known about theS. mutans population, including the clonal relationships among strains ofS. mutans , in relation to the particular clones that cause systemic diseases. To address this issue, we have developed a multilocus sequence typing (MLST) scheme forS. mutans . Eight housekeeping gene fragments were sequenced from each of 102S. mutans isolates collected from the four serotypes in Japan and Finland. Between 14 and 23 alleles per locus were identified, allowing us theoretically to distinguish more than 1.2 × 1010 sequence types. We identified 92 sequence types in these 102 isolates, indicating thatS. mutans contains a diverse population. Whereas serotypec strains were widely distributed in the dendrogram, serotypee ,f , andk strains were differentiated into clonal complexes. Therefore, we conclude that the ancestral strain ofS. mutans was serotypec . No geographic specificity was identified. However, the distribution of the collagen-binding protein gene (cnm ) and direct evidence of mother-to-child transmission were clearly evident. In conclusion, the superior discriminatory capacity of this MLST scheme forS. mutans may have important practical implications.