Distribution ofPorphyromonas gingivalis fimAandmfa1fimbrial genotypes in subgingival plaques

Abstract

BackgroundStrains of periodontal disease-associated bacterium Porphyromonas gingivalis have different pathogenicity, which can be attributed to clonal genetic diversity. P. gingivalis typically expresses two types of fimbriae, FimA and Mfa1, which comprise six (I, Ib, II, III, IV, and V) and two (mfa53 and mfa70) genotypes, respectively. This study was conducted to investigate the distribution of the two fimbrial genotypes of P. gingivalis in clinical specimens.MethodsSubgingival plaques were collected from 100 participants during periodontal maintenance therapy and examined for P. gingivalis fimbrial genotypes by direct polymerase chain reaction and/or DNA sequencing. We also analyzed the relationship between fimbrial genotypes and clinical parameters of periodontitis recorded at the first medical examination.ResultsBoth fimbrial types could be detected in 63 out of 100 samples; among them, fimA genotype II was found in 33 samples (52.4%), in which the mfa70 genotype was 1.75 times more prevalent than mfa53. The total detection rate of fimA genotypes I and Ib was 38.1%; in these samples, the two mfa1 genotypes were observed at a comparable frequency. In two samples positive for fimA III (3.2%), only mfa53 was detected, whereas in four samples positive for fimA IV (6.3%), the two mfa1 genotypes were equally represented, and none of fimA V-positive samples defined the mfa1 genotype. No associations were found between clinical parameters and fimbrial subtype combinations.DiscussionBoth P. gingivalis fimbrial types were detected at various ratios in subgingival plaques, and a tendency for fimA and mfa1 genotype combinations was observed. However, there was no association between P. gingivalis fimbrial genotypes and periodontitis severity.

Phylogenetic diversity in fim and mfa gene clusters between Porphyromonas gingivalis and Porphyromonas gulae, as a potential cause of host specificity

“…Type 70 seemed a major mfa1 genotype for P. gingivalis , whereas most P. gulae strains had type 53 ( Figure 4 ). In a previous study, the relationship between the fimA and mfa genotypes was weakly observed in P. gingivalis , such as type II strains harboring type 70 mfa1 rather than type 53, and mfa1 was absent in the type V strains [ 13 ]. These previous findings were consistent with our observation that most of type II strains were type 70 in the mfa1 genotypes, but were not consistent with the presence of mfa1 in P. gingivalis strains with type V fimA .…”

“…Fimbriae of P. gingivalis are the virulence factor for adhering to a host cell and tissue as the first step of colonization [ 6 ]. In P. gingivalis , fimbriae are classified as FimA fimbriae and Mfa1 fimbriae [ 13 ]. FimA is assembled into the polymer with the expression of accessory proteins FimBCDE [ 14 ].…”

Heme Competition Triggers an Increase in the Pathogenic Potential of Porphyromonas gingivalis in Porphyromonas gingivalis-Candida albicans Mixed Biofilm

“…The detection rate of Porphyromonas gingivalis , one of the major pathogens of periodontitis in subgingival biofilm, is as high as 60.9% ( Nagano et al, 2018 ). In recent years, it has been found that Candida albicans , a pathogen of denture stomatitis, also has an increased frequency of subgingival separation in patients with periodontitis ( McManus et al, 2012 ; Sardi et al, 2012 ; Marsh and Zaura, 2017 ).…”

Chemical and structural composition of black pigmented supragingival biofilm of bovines with periodontitis

“…It is particularly relevant to highlight that in ruminant animals the chemical and microbial content of the rumen interacts with the oral counterparts (Myer et al 2015). Among the microbial adhesins, the role played by fimbriae and other appendicular structures deserves attention (Marsh et al 2011), especially among the main periodontal pathogens, such as the genus Porphyromonas (Socransky & Haffajee 2005, Nagano et al 2018.…”