title: Quantitative detection of Porphyromonas gingivalis fimA genotypes in dental plaque.
abstract: We developed quantitative fimA genotype assays and applied them in a pilot study investigating the fimbrial genotype distribution of Porphyromonas gingivalis in European subjects with or without chronic periodontitis. P. gingivalis was found in 71% and 9% of the samples from patients and healthy subjects, respectively. Enumeration of total P. gingivalis cell numbers by polymerase chain reaction and immunofluorescence showed excellent correspondence (r = 0.964). 73% of positive samples contained multiple fimA genotypes, but generally one genotype predominated by one to three orders of magnitude. Genotype II predominated in 60% of the samples. Genotype IV occurred with similar prevalence (73%) as genotype II but predominated in only 20% of the samples. Genotypes I, III and V were of much lower prevalence and cell densities of the latter two remained sparse. Our results suggest marked differences among the fimA genotypes' ability to colonize host sites with high cell numbers.
authors.affiliation: Institute for Oral Biology, Section for Oral Microbiology and General Immunology, Center for Dental, Oral Medicine and Maxillofacial Surgery, University of Zürich, Plattenstrasse 11, CH-8028 Zürich, Switzerland.
authors.forename: Jan R
authors.initials: JR
authors.lastname: van der Ploeg
authors.forename: Elin
authors.initials: E
authors.lastname: Giertsen
authors.forename: Beat
authors.initials: B
authors.lastname: Lüdin
authors.forename: Christian
authors.initials: C
authors.lastname: Mörgeli
authors.forename: Annelies S
authors.initials: AS
authors.lastname: Zinkernagel
authors.forename: Rudolf
authors.initials: R
authors.lastname: Gmür
mesh_terms: D000328:Adult; D000368:Aged; D015169:Colony Count, Microbial / Q000379:methods; D004269:DNA, Bacterial / Q000302:isolation & purification; D003773:Dental Plaque / Q000382:microbiology*; D005260:Female; D036781:Fimbriae Proteins / Q000235:genetics*; D005455:Fluorescent Antibody Technique; D005798:Genes, Bacterial; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000382:microbiology; D010865:Pilot Projects; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic; D016966:Porphyromonas gingivalis / Q000145:classification* / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; C063055:fimbrillin; D036781:Fimbriae Proteins