title: Multilocus sequence analysis of Porphyromonas gingivalis indicates frequent recombination.
abstract: In this study, the genetic relationship of 19 Porphyromonas gingivalis isolates from patients with periodontitis was investigated by multilocus sequence analysis. Internal 400-600 bp DNA fragments of the 10 chromosomal genes ef-tu, ftsQ, hagB, gpdxJ, pepO, mcmA, dnaK, recA, pga and nah were amplified by PCR and sequenced. No two isolates were identical at all 10 loci. Phylogenetic analyses indicated a panmictic population structure of P. gingivalis. Split decomposition analysis, calculation of homoplasy ratios and analyses of clustered polymorphisms all indicate that recombination plays a major role in creating the genetic heterogeneity of P. gingivalis. A standardized index of association of 0.0898 indicates that the P. gingivalis genes analysed are close to linkage equilibrium.
authors.affiliation: Institut für Hygiene und Mikrobiologie der Bayerischen Julius-Maximilians-Universität, 97080 Würzburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Koehler
authors.affiliation: Institut für Hygiene, 48149 Münster, Germany.
authors.forename: Helge
authors.initials: H
authors.lastname: Karch
authors.affiliation: Poliklinik für Parodontologie der Westfälischen Wilhelms-Universität, 48149 Münster, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Beikler
authors.affiliation: Poliklinik für Parodontologie der Westfälischen Wilhelms-Universität, 48149 Münster, Germany.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Flemmig
authors.affiliation: Institut für Hygiene und Mikrobiologie der Bayerischen Julius-Maximilians-Universität, 97080 Würzburg, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Suerbaum
authors.affiliation: Institut für Hygiene und Mikrobiologie der Bayerischen Julius-Maximilians-Universität, 97080 Würzburg, Germany.
authors.forename: Herbert
authors.initials: H
authors.lastname: Schmidt
mesh_terms: D002876:Chromosomes, Bacterial; D004269:DNA, Bacterial / Q000032:analysis; D005798:Genes, Bacterial; D018740:Genetic Heterogeneity; D008969:Molecular Sequence Data; D010802:Phylogeny; D011110:Polymorphism, Genetic; D016966:Porphyromonas gingivalis / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial