Porphyromonas canoris sp. nov., an asaccharolytic, black-pigmented species from the gingival sulcus of dogs

Porphyromonas levii - A Boon for Periodontists?

The majority of species previously categorized as Bacteroides have been reassigned into new genera. Bacteroides levii (Holdeman, Cato, and Mooretaxonomic)'s status has remained uncertain. This species shares a high degree of similarity with members of the genus Porphyromonas based on biochemical, chemical, and comparative 16s rRNA sequence analysis. As a result, Bacteroides levii (Holdeman, Cato, and Moore) was reclassified as Porphyromonas levii comb. now under the genus Porphyromonas.

Phylogenomic analysis of the Porphyromonas gingivalis - Porphyromonas gulae duo: approaches to the origin of periodontitis

Porphyromonas gingivalis is an oral human pathogen associated with the onset and progression of periodontitis, a chronic immune-inflammatory disease characterized by the destruction of the teeth-supporting tissue. P. gingivalis belongs to the genus Porphyromonas, which is characterized by being composed of Gram-negative, asaccharolytic, non-spore-forming, non-motile, obligatory anaerobic species, inhabiting niches such as the oral cavity, urogenital tract, gastrointestinal tract and infected wound from different mammals including humans. Among the Porphyromonas genus, P. gingivalis stands out for its specificity in colonizing the human oral cavity and its keystone pathogen role in periodontitis pathogenesis. To understand the evolutionary process behind P. gingivalis in the context of the Pophyoromonas genus, in this study, we performed a comparative genomics study with publicly available Porphyromonas genomes, focused on four main objectives: (A) to confirm the phylogenetic position of P. gingivalis in the Porphyromonas genus by phylogenomic analysis; (B) the definition and comparison of the pangenomes of P. gingivalis and its relative P. gulae; and (C) the evaluation of the gene family gain/loss events during the divergence of P. gingivalis and P. gulae; (D) the evaluation of the evolutionary pressure (represented by the calculation of Tajima-D values and dN/dS ratios) comparing gene families of P. gingivalis and P. gulae. Our analysis found 84 high-quality assemblies representing P. gingivalis and 14 P. gulae strains (from a total of 233 Porphyromonas genomes). Phylogenomic analysis confirmed that P. gingivalis and P. gulae are highly related lineages, close to P. loveana. Both organisms harbored open pangenomes, with a strong core-to-accessory ratio for housekeeping genes and a negative ratio for unknown function genes. Our analyses also characterized the gene set differentiating P. gulae from P. gingivalis, mainly associated with unknown functions. Relevant virulence factors, such as the FimA, Mfa1, and the hemagglutinins, are conserved in P. gulae, P. gingivalis, and P. loveana, suggesting that the origin of those factors occurred previous to the P. gulae - P. gingivalis divergence. These results suggest an unexpected evolutionary relationship between the P. gulae - P. gingivalis duo and P. loveana, showing more clues about the origin of the role of those organisms in periodontitis.

Porphyromonas spp. have an extensive host range in ill and healthy individuals and an unexpected environmental distribution: A systematic review and meta-analysis

Studies on the anaerobic bacteria Porphyromonas, mainly focused on P. gingivalis, have revealed new bacterial structures, metabolic pathways, and physiologic functionalities. Porphyromonas are mainly described as being associated with mammals and involved in chronic oral infections and secondary pathologies such as cancers or neurodegenerative diseases. In this review, we collected and analyzed information regarding Porphyromonas isolation sites and associated conditions and showed that Porphyromonas are detected in numerous pristine and anthropic environments and that their host range appears wider than previously believed, including aquatic animals, arthropods, and birds, even if their predominant hosts remain humans, pets, and farm animals. Our analyses also revealed their presence in multiple organs and in a substantial proportion of healthy contexts. Overall, the growing numbers of microbiota studies have allowed unprecedented advances in the understanding of Porphyromonas ecology but raise questions regarding their phylogenic assignment. In conclusion, this systematic and meta-analysis provides an overview of current knowledge regarding Porphyromonas ecological distribution and encourages additional research to fill the knowledge gaps to better understand their environmental distribution and inter- and intra-species transmission.

Dental Plaque Flora of the Dog with Reference to Fastidious and Anaerobic Bacteria Associated with Bites

Animal bite wounds are amongst the most common types of traumatic injuries in humans. The organisms isolated from these wounds generally reflect the oral flora of the biting animal and may be fastidious in nature and difficult to identify. This study was undertaken to determine the prevalence of Eikenella corrodens, Actinobacillus actinomycetemcomitans, Porphyromonas and Prevotella spp. in supragingival dental plaque collected from the right maxillary canine and carnassial teeth and the right mandibular canine tooth of dogs. In part one of the study, 30 dogs were used. E. corrodens was found in 62% of these dogs and 44% of individual plaque samples. A. actinomycetemcomitans was not detected in any of the dogs sampled. In pan two, 34 dogs were used to determine the prevalence of the black pigmented anaerobic bacilli (Porphyromonas and Prevotella spp.). Porphyromonas gingivalis was present in 68% of these dogs and 47% of individual plaque samples. Prevotella intermedia was present in 44% of the dogs and 23% of individual plaque samples. The recently described Porphyromonas canoris, Porphyromonas salivosa, Porphyromonas cangingivalis, Porphyromonas cansulci, Porphyromonas crevioricanis and Prevotella denticola species were isolated from only 9%, 6%, 3%, 3%, 3% and 3% of dogs respectively. Porphyromonas gingivicanis was not isolated from any of the animals sampled. In conclusion, black-pigmented anaerobic bacilli were isolated from 91% of the animals sampled and therefore constitute a significant risk with respect to bite wound infections. It is also suggested that the prevalence of E. corrodens in wound infections has been underestimated in previous reports because of use of inappropriate techniques for detecting this organism.

A Pyrosequencing Investigation of Differences in the Feline Subgingival Microbiota in Health, Gingivitis and Mild Periodontitis

Periodontitis is the most frequently diagnosed health problem in cats yet little is known about the bacterial species important for the disease. The objective of this study was to identify bacterial species associated with health, gingivitis or mild periodontitis (<25% attachment loss) in feline plaque. Knowledge of these species is a first step in understanding the potential for improving oral health of cats via dietary interventions that alter the proportions of influential species. Subgingival plaque samples were collected from 92 cats with healthy gingiva, gingivitis or mild periodontitis. Pyrosequencing of the V1-V3 region of the 16S rDNA from these plaque samples generated more than one million reads and identified a total of 267 operational taxonomic units after bioinformatic and statistical analysis. Porphyromonas was the most abundant genus in all gingival health categories, particularly in health along with Moraxella and Fusobacteria. The Peptostreptococcaceae were the most abundant family in gingivitis and mild periodontitis. Logistic regression analysis identified species from various genera that were significantly associated with health, gingivitis or mild periodontitis. The species identified were very similar to those observed in canine plaque in the corresponding health and disease states. Such similarities were not observed between cat and human at the bacterial species level but with disease progression similarities did emerge at the phylum level. This suggests that interventions targeted at human pathogenic species will not be effective for use in cats but there is more potential for commonalities in interventions for cats and dogs.

Molecular identification of bacteria associated with canine periodontal disease

Periodontal disease is one of the most common diseases of adult dogs, with up to 80% of animals affected. The aetiology of the disease is poorly studied, although bacteria are known to play a major role. The purpose of this study was to identify the bacteria associated with canine gingivitis and periodontitis and to compare this with the normal oral flora. Swabs were obtained from the gingival margin of three dogs with gingivitis and three orally healthy controls, and subgingival plaque was collected from three dogs with periodontitis. Samples were subjected to routine bacterial culture. The prevalent species identified in the normal, gingivitis and periodontitis groups were uncultured bacterium (12.5% of isolates), Bacteroides heparinolyticus/Pasteurella dagmatis (10.0%) and Actinomyces canis (19.4%), respectively. Bacteria were also identified using culture-independent methods (16S rRNA gene sequencing) and the predominant species identified were Pseudomonas sp. (30.9% of clones analysed), Porphyromonas cangingivalis (16.1%) and Desulfomicrobium orale (12.0%) in the normal, gingivitis and periodontitis groups, respectively. Uncultured species accounted for 13.2%, 2.0% and 10.5%, and potentially novel species for 38.2%, 38.3% and 35.3%, of clones in the normal, gingivitis and periodontitis groups, respectively. This is the first study to use utilise culture-independent methods for the identification of bacteria associated with this disease. It is concluded that the canine oral flora in health and disease is highly diverse and also contains a high proportion of uncultured and, in particular, potentially novel species.

Butyricimonas synergistica gen. nov., sp. nov. and Butyricimonas virosa sp. nov., butyric acid-producing bacteria in the family 'Porphyromonadaceae' isolated from rat faeces

Two bacterial strains, designated MT01(T) and MT12(T), isolated from rat faeces were characterized by using a polyphasic taxonomic approach that included analysis of their phenotypic and biochemical features, cellular fatty acid profiles, menaquinone profiles and phylogeny based on 16S rRNA gene sequences. The 16S rRNA gene sequence analysis showed that these strains were members of the family 'Porphyromonadaceae'. The strains shared 94 % 16S rRNA gene sequence similarity with each other and were related to Odoribacter splanchnicus NCTC 10825(T) (86-87 % sequence similarity). The strains consisted of obligately anaerobic, non-pigmented, non-spore-forming, non-motile, Gram-negative rods. Growth of the strains was inhibited on medium containing 20 % bile. The two strains produced significant levels of butyric and isobutyric acids as end products from glucose. Although the major cellular fatty acid of these two strains and O. splanchnicus JCM 15291(T) was iso-C(15 : 0), strains MT01(T) and MT12(T) showed a higher level of iso-C(15 : 0) (66 and 74 %, respectively) than did O. splanchnicus JCM 15291(T) (48 %). In addition, the ratios of iso-C(15 : 0) to anteiso-C(15 : 0) in whole-cell methanolysates of the two isolates were very much higher than that of O. splanchnicus JCM 15291(T). The major menaquinone of the isolates was MK-10. This menaquinone composition was different from those of other genera of the family 'Porphyromonadaceae', such as Barnesiella (predominant menaquinones: MK-11 and MK-12), Odoribacter (MK-9), Paludibacter (MK-8), Parabacteroides (MK-9 and MK-10), Porphyromonas (MK-9 and MK-10) and Tannerella (MK-10 and MK-11). Menaquinone composition is therefore an important chemotaxonomic characteristic of these micro-organisms. Strains MT01(T) and MT12(T) have DNA G+C contents of 46 mol%. On the basis of these data, strains MT01(T) and MT12(T) represent two novel species of a novel genus, for which the names Butyricimonas synergistica gen. nov., sp. nov. and Butyricimonas virosa sp. nov., respectively, are proposed. The type strains of B. synergistica and B. virosa are MT01(T) (=JCM 15148(T) =CCUG 56610(T)) and MT12(T) (=JCM 15149(T)=CCUG 56611(T)), respectively.

Phylogenetic analysis of Porphyromonas species isolated from the oral cavity of Australian marsupials

Porphyromonas species are frequently isolated from the oral cavity and are associated with periodontal disease in both animals and humans. Black, pigmented Porphyromonas spp. isolated from the gingival margins of selected wild and captive Australian marsupials with varying degrees of periodontal disease (brushtail possums, koalas and macropods) were compared phylogenetically to Porphyromonas strains from non-marsupials (bear, wolf, coyote, cats and dogs) and Porphyromonas gingivalis strains from humans using 16S rRNA gene sequence analysis. The results of the phylogenetic analysis identified three distinct groups of strains. A monophyletic P. gingivalis group (Group 1) contained only strains isolated from humans and a Porphyromonas gulae group (Group 2) was divided into three distinct subclades, each containing both marsupial and non-marsupial strains. Group 3, which contained only marsupial strains, including all six strains isolated from captive koalas, was genetically distinct from P. gulae and may constitute a new Porphyromonas species.

Evaluation of a monovalent companion animal periodontal disease vaccine in an experimental mouse periodontitis model

Periodontal disease in companion animals is clinically similar to that of human periodontal disease. Despite the usage of veterinary procedures and antibiotic therapy, the disease still remains as one of the most highly prevalent disorders seen by veterinarians. The goal of this study was to evaluate the immunogenic properties and vaccine performance of a monovalent canine periodontal disease vaccine in the mouse oral challenge model of periodontitis. Mice vaccinated subcutaneously with inactivated, whole-cell bacterin preparations of Porphyromonas gulae displayed both high titers of anti-P. gulae specific antibodies and significantly reduced alveolar bone loss in response to homologous, heterologous, and cross-species challenge. Based on the results of these studies, a periodontal disease vaccine may be a useful tool in preventing the progression of periodontitis in animals.

Pigmented-anaerobic bacteria associated with canine periodontitis

The etiology of human periodontal disease has been the focus of considerable research, yet relatively little is known about the causative agents of companion animal periodontitis. In humans, Porphyromonas gingivalis, a black-pigmented anaerobic bacteria (BPAB), has been implicated as the primary periopathogen. It has been demonstrated that BPAB are also found in companion animal periodontal pockets. While some animal BPAB have been individually identified, a study to identify the most frequently isolated subgingival BPAB has not been completed using genetic tools. The objective of this work was to identify the types and relative frequencies of pigmented anaerobic bacteria found in the periodontal pockets of dogs. Porphyromonas salivosa, Porphyromonas denticanis (a novel species) and Porphyromonas gulae were found to be the most frequently isolated BPAB associated with canine periodontitis.

Culture-independent identification of periodontitis-associated Porphyromonas and Tannerella populations by targeted molecular analysis

Periodontitis is the commonest bacterial disease of humans and is the major cause of adult tooth loss. About half of the oral microflora is unculturable; and 16S rRNA PCR, cloning, and sequencing techniques have demonstrated the high level of species richness of the oral microflora. In the present study, a PCR primer set specific for the genera Porphyromonas and Tannerella was designed and used to analyze the bacterial populations in subgingival plaque samples from inflamed shallow and deep sites in subjects with periodontitis and shallow sites in age- and sex-matched controls. A total of 308 clones were sequenced and found to belong to one of six Porphyromonas or Tannerella species or phylotypes, one of which, Porphyromonas P3, was novel. Tannerella forsythensis was found in significantly higher proportions in patients than in controls. Porphyromonas catoniae and Tannerella phylotype BU063 appeared to be associated with shallow sites. Targeted culture-independent molecular ecology studies have a valuable role to play in the identification of bacterial targets for further investigations of the pathogenesis of bacterial infections.

Measurement of peptidase activity and evaluation of effectiveness of administration of minocycline for treatment of dogs with periodontitis

OBJECTIVE

To determine clinical, enzymatic, and microbiologic effects of controlled-release localized administration of minocycline on dogs with periodontitis.

ANIMALS

Five adult Beagles with periodontitis.

PROCEDURE

After tooth scaling and root planing, 2 treatment, 1 placebo, and 1 control site were selected for each dog. Treatment sites (n = 10) received a periodontal formulation of minocycline hydrochloride, placebo sites (5) received ointment without minocycline, and control sites (5) did not receive ointment. Treatments were administered 4 times at weekly intervals. Peptidase activity and clinical and microbiologic effects were evaluated and compared among sites for 17 weeks.

RESULTS

Bleeding of the gums on probing (BOP) and pocket depth (PD) improved at the treatment site and were maintained for 13 weeks after treatment. However, BOP and PD in placebo and control sites increased from weeks 9 to 17 Peptidase activity in the periodontal pocket decreased noticeably from week 1 to 17, compared with baseline values for the treatment site. However, peptidase activity for placebo and control sites increased and were above baseline values on week 9 and week 13, respectively. Total bacterial counts decreased by 90% for treatment sites and remained at that value for 13 weeks. However, for placebo and control sites, bacterial counts increased and reached the baseline value on week 17.

CONCLUSIONS AND CLINICAL RELEVANCE

Increased peptidase activity is correlated with the progression of periodontitis in dogs. Treatment with minocycline, using a localized delivery system, was effective in dogs for at least 13 weeks after cessation of drug administration.

Phospholipid analogues of Porphyromonas gingivalis

Porphyromonas has lipids containing hydroxy acids and C16:0 and iso-C15:0 major monocarboxylic acids among others. Nothing is known of its individual phospholipid molecular species. The aim of this study was to determine molecular weights and putative identities of individual phospholipid molecular species extracted from Porphyromonas gingivalis (seven strains), P. asaccharolytica (one strain) and P. endodontalis (two strains). Cultures on Blood-Fastidious Anaerobe Agar were harvested, washed and freeze-dried. Phospholipids were extracted and separated by fast atom bombardment mass spectrometry (FAB MS) in negative-ion mode. Phospholipid classes were also separated by thin layer chromatography (TLC). The major anions in the range m/z 209-299 were consistent with the presence of the C13: 0, C15: 0, C16: 0 and C18: 3 mono-carboxylate anions. Major polar lipid anion peaks in the range m/z 618-961 were consistent with the presence of molecular species of phosphatidylethanolamine, phosphatidylglycerol and with unidentified lipid analogues. Porphyromonas gingivalis differed from comparison strains of other species by having major anions with m/z 932, 946 and 960. Unusually, a feline strain of P. gingivalis had a major peak of m/z 736. Selected anions were studied by tandem FAB MS which revealed that peaks with m/z 653 and 946 did not correspond to commonly occurring classes of polar lipids. They were however, glycerophosphates. It is concluded that the polar lipid analogue profiles obtained with Porphyromonas are quite different from those of the genera Prevotella and Bacteroides but reveal heterogeneity within P. gingivalis.

Microbiota saprófita associada à doença periodontal em cães

Realizou-se um estudo sobre a microbiota saprófita associada à doença periodontal espontânea em cães com o objetivo de identificar as bactérias anaeróbias predominantes nas lesões. Com auxílio de cureta odontológica, amostras colhidas diretamente do espaço subgengival foram semeadas em meio CDC (Central for Disease Control) para anaeróbios e incubadas, em anaerobiose, a 37°C, por sete dias. A caracterização das colônias foi realizada por meio da morfologia e do teste bioquímico (Sistema API 20A<FONT FACE="Symbol">Ò</FONT>). Identificaram-se os seguintes gêneros: Prevotella spp., Bacteroides spp., Propionibacterium spp., Gemella spp., Actinomyces spp., Eubacterium spp. e Porphyromonas spp.

Periodontal disease in dogs. Etiopathogenesis, prevalence, and significance

Periodontal disease is very common and often very severe in dogs. It is caused by accumulation of bacterial plaque, particularly Gram-negative anaerobic rods. Tissue destruction results from autodegradation induced by the continuing inflammatory response. Small dogs are particularly at risk. Prevention by retarding accumulation of plaque is the key concept.

Prevalence of Porphyromonas and Prevotella species in the dental plaque of dogs

The prevalence and populations of Porphyromonas and Prevotella species were determined in three samples of dental plaque from each of 34 healthy dogs. Porphyromonas gingivalis was present in 68 per cent of the dogs and 47 per cent of the plaque samples. The counts of P gingivalis increased with age (P < 0.1), the amount of plaque (P < 0.05) and the degree of gingivitis (P < 0.1). Prevotella intermedia was present in 44 per cent of the dogs and 23 per cent of the plaque samples. The counts of P intermedia were correlated with the amount of plaque (P < 0.05) and the degree of gingivitis (P < 0.1). Porphyromonas canoris, P salivosa, P cangingivalis, P cansulci, P crevioricanis and Prevotella denticola were isolated from only 9, 6, 3, 3, 3 and 3 per cent of the dogs, respectively. Porphyromonas gingivicanis was not isolated from any of the animals sampled. There was a highly significant (P < 0.001) correlation between the amount of plaque, the extent of gingivitis and the age of the dog.