Oral microbiome sequencing revealed the enrichment of Fusobacterium sp., Porphyromonas sp., Campylobacter sp., and Neisseria sp. on the oral malignant fibroma surface of giant panda.

Introduction: Microbial community composition is closely associated with host disease onset and progression, underscoring the importance of understanding host-microbiota dynamics in various health contexts. Methods: In this study, we utilized full-length 16S rRNA gene sequencing to conduct species-level identification of the microorganisms in the oral cavity of a giant panda (Ailuropoda melanoleuca) with oral malignant fibroma. Results: We observed a significant difference between the microbial community of the tumor side and non-tumor side of the oral cavity of the giant panda, with the latter exhibiting higher microbial diversity. The tumor side was dominated by specific microorganisms, such as Fusobacterium simiae, Porphyromonas sp. feline oral taxon 110, Campylobacter sp. feline oral taxon 100, and Neisseria sp. feline oral taxon 078, that have been reported to be associated with tumorigenic processes and periodontal diseases in other organisms. According to the linear discriminant analysis effect size analysis, more than 9 distinct biomarkers were obtained between the tumor side and non-tumor side samples. Furthermore, the Kyoto Encyclopedia of Genes and Genomes analysis revealed that the oral microbiota of the giant panda was significantly associated with genetic information processing and metabolism, particularly cofactor and vitamin, amino acid, and carbohydrate metabolism. Furthermore, a significant bacterial invasion of epithelial cells was predicted in the tumor side. Discussion: This study provides crucial insights into the association between oral microbiota and oral tumors in giant pandas and offers potential biomarkers that may guide future health assessments and preventive strategies for captive and aging giant pandas.

Embolic necrosuppurative pneumonia in domestic cats induced by a novel Neisseria species.

Three cats, aged 2 to 11 years, presented to the University of Minnesota Veterinary Diagnostic Laboratory over a 3-year period following euthanasia or death due to respiratory distress. Thoracic radiographs revealed nodular, soft tissue opacities throughout the lung fields in all cases. On postmortem examination, approximately 60% to 80% of the lung parenchyma were expanded by multifocal to coalescing, well-demarcated, beige, semi-firm nodules. Histologically, large numbers of neutrophils, fewer macrophages, fibrin, and cellular and karyorrhectic debris effaced the pulmonary parenchyma. The inflammatory foci contained aggregates of gram-negative cocci. 16s rRNA Sanger sequencing and whole-genome sequencing identified the bacteria isolated from the lung of all cats under aerobic conditions as a novel Neisseria spp. Based on whole-genome sequence analysis, all 3 sequences shared 92.71% and 92.67% average nucleotide identity with closely related Neisseria animaloris NZ LR134440T and Neisseria animaloris GCA 002108605T, respectively. The in silico DNA-DNA hybridization identity compared to our isolates was 46.6% and 33.8% with strain DSM Neisseria zoodegmatis 21642 and strain DSM 21643, respectively. All 3 sequences have less than 95% average nucleotide identity and less than 70% DNA-DNA hybridization identity, suggesting that the 3 isolates are a novel species of the genus Neisseria. Infection with Neisseria spp. induces an embolic pneumonia in cats that radiographically and pathologically resembles a metastatic neoplastic process and should be considered among the etiologic differential diagnoses in cases of infectious pulmonary disease with a disseminated, nodular lung pattern.

Beyond the usual suspects: Reviewing infections caused by typically-commensal Neisseria species.

OBJECTIVE: Few data outside of individual case reports are available on non-meningococcal, non-gonococcal species of Neisseria as causative agents of invasive disease. This review collates disease, organism and patient information from case reports on the topic. METHODS: A literature search was performed examining articles describing diseases caused by non-meningococcal and non-gonococcal Neisseria. FINDINGS: Neisseria present as opportunistic pathogens causing a wide variety of diseases including serious presentations, endocarditis being the most common condition described and N. mucosa the most commonly presenting pathogen overall. Disease may occur in otherwise healthy patients, although risk factors for infection include recent surgery, an immunocompromised state, poor oral health, and intravenous drug use. CONCLUSIONS: Commensal Neisseria infections are rare but can present serious invasive diseases. Further research is required to determine why some species cause disease more than others or why some are inclined towards particular manifestations.

Neisseria lisongii sp. nov. and Neisseria yangbaofengii sp. nov., isolated from the respiratory tracts of marmots.

Four Gram-stain-negative, oxidase-positive, non-motile, cocci-shaped bacteria strains (ZJ106T, ZJ104, ZJ785T and ZJ930) were isolated from marmot respiratory tracts. Phylogenetic analyses based on 16S rRNA genes, 53 ribosomal protein sequences and 441 core genes supported that all four strains belonged to the genus Neisseria with close relatives Neisseria weixii 10022T and Neisseria iguanae ATCC 51483T. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values were below the species-level thresholds (95-96 % for ANI, and 70 % for dDDH). The major fatty acids of all four strains were C16 : 1 ω7c /C16 : 1 ω6c, C16 : 0 and C18 : 1 ω9c. Major polar lipids were composed of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. MK-8 was the major menaquinone. Based on Virulence Factor Database analysis, the four strains were found to contain NspA and PorB H-factor binding proteins that promote evasion of host immunity. Strains ZJ106T and ZJ104 contained structures similar to the capsule synthesis manipulator of Neisseria meningitidis. Based on phenotypic and phylogenetic evidence, we propose that strains ZJ106T and ZJ785T represent two novel species of the genus Neisseria, respectively, with the names Neisseria lisongii sp. nov. and Neisseria yangbaofengii sp. nov. The type strains are ZJ106T (=GDMCC 1.3111T=JCM 35323T) and ZJ785T (=GDMCC 1.1998T=KCTC 82336T).

Structural basis for the toxic activity of MafB2 from maf genomic island 2 (MGI-2) in N. meningitidis B16B6.

The Maf polymorphic toxin system is involved in conflict between strains found in pathogenic Neisseria species such as Neisseria meningitidis and Neisseria gonorrhoeae. The genes encoding the Maf polymorphic toxin system are found in specific genomic islands called maf genomic islands (MGIs). In the MGIs, the MafB and MafI encode toxin and immunity proteins, respectively. Although the C-terminal region of MafB (MafB-CT) is specific for toxic activity, the underlying enzymatic activity that renders MafB-CT toxic is unknown in many MafB proteins due to lack of homology with domain of known function. Here we present the crystal structure of the MafB2-CTMGI-2B16B6/MafI2MGI-2B16B6 complex from N. meningitidis B16B6. MafB2-CTMGI-2B16B6 displays an RNase A fold similar to mouse RNase 1, although the sequence identity is only ~ 14.0%. MafB2-CTMGI-2B16B6 forms a 1:1 complex with MafI2MGI-2B16B6 with a Kd value of ~ 40 nM. The complementary charge interaction of MafI2MGI-2B16B6 with the substrate binding surface of MafB2-CTMGI-2B16B6 suggests that MafI2MGI-2B16B6 inhibits MafB2-CTMGI-2B16B6 by blocking access of RNA to the catalytic site. An in vitro enzymatic assay showed that MafB2-CTMGI-2B16B6 has ribonuclease activity. Mutagenesis and cell toxicity assays demonstrated that His335, His402 and His409 are important for the toxic activity of MafB2-CTMGI-2B16B6, suggesting that these residues are critical for its ribonuclease activity. These data provide structural and biochemical evidence that the origin of the toxic activity of MafB2MGI-2B16B6 is the enzymatic activity degrading ribonucleotides.

Neisseria species as pathobionts in bronchiectasis.

Neisseria species are frequently identified in the bronchiectasis microbiome, but they are regarded as respiratory commensals. Using a combination of human cohorts, next-generation sequencing, systems biology, and animal models, we show that bronchiectasis bacteriomes defined by the presence of Neisseria spp. associate with poor clinical outcomes, including exacerbations. Neisseria subflava cultivated from bronchiectasis patients promotes the loss of epithelial integrity and inflammation in primary epithelial cells. In vivo animal models of Neisseria subflava infection and metabolipidome analysis highlight immunoinflammatory functional gene clusters and provide evidence for pulmonary inflammation. The murine metabolipidomic data were validated with human Neisseria-dominant bronchiectasis samples and compared with disease in which Pseudomonas-, an established bronchiectasis pathogen, is dominant. Metagenomic surveillance of Neisseria across various respiratory disorders reveals broader importance, and the assessment of the home environment in bronchiectasis implies potential environmental sources of exposure. Thus, we identify Neisseria species as pathobionts in bronchiectasis, allowing for improved risk stratification in this high-risk group.

Genomic sequence of the non-pathogen Neisseria sp. strain MA1-1 with antibiotic resistance and virulence factors isolated from a head and neck cancer patient.

Recent research has claimed virulence factors or antimicrobial resistance in commensal or non-pathogenic Neisseria spp. This study aimed to isolate and analyze commensal microorganisms related to the genus Neisseria from the oral cavity of a patient with head and neck cancer. We successfully isolated strain MA1-1 and identified its functional gene contents. Although strain MA1-1 was related to Neisseria flava based on 16S rRNA gene sequence similarity, genomic relatedness analysis revealed that strain MA1-1 was closely related to Neisseria mucosa, reported as a commensal Neisseria species. The strain MA1-1 genome harbored genes for microaerobic respiration and the complete core metabolic pathway with few transporters for nutrients. A number of genes have been associated with virulence factors and resistance to various antibiotics. In addition, the comparative genomic analysis showed that most genes identified in the strain MA1-1 were shared with other Neisseria spp. including two well-known pathogens, Neisseria gonorrhoeae and Neisseria meningitidis. This indicates that the gene content of intra-members of the genus Neisseria has been evolutionarily conserved and is stable, with no gene recombination with other microbes in the host. Finally, this study provides more fundamental interpretations for the complete gene sequence of commensal Neisseria spp. and will contribute to advancing public health knowledge.

Meningite bacteriana: uma revisão / Bacterial meningitis: a review

A meningite bacteriana é uma inflamação das leptomeninges que envolvem o Sistema Nervoso Central. Essa patologia, que possui diversos agentes etiológicos, apresenta-se na forma de síndrome, com quadro clínico grave. Entre as principais bactérias que causam a meningite, estão a Neisseria meningitis e Streptococcus pneumoniae. A transmissão ocorre através das vias aéreas por meio de gotículas, sendo a corrente sanguínea a principal rota para as bactérias chegarem à barreira hematoencefálica e, a partir dessa, até as meninges. Atualmente existem vários métodos de diagnóstico precisos, onde a cultura de líquido cefalorraquidiano (LCR) é o método padrão ouro. Ademais, a melhora na qualidade do tratamento com beta-lactâmicos e a maior possibilidade de prevenção, devido à elevação do número e da eficácia de vacinas, vem contribuindo para redução dos casos da doença e de sua gravidade. Porém, apesar desses avanços, ainda há um elevado número de mortalidades e sequelas causadas por essa síndrome.

Bacterial meningitis is an inflammation of the leptomeninges that surround the Central Nervous System. This pathology, which has several etiological agents, is presented as a syndrome with a severe clinical scenario. The main bacteria causing meningitis include Neisseria meningitis and Streptococcus pneumoniae. It can be transmitted by droplets through the airways, with the bacteria using the bloodstream as the main route to reach the blood-brain barrier, and from there to the meninges. There are currently several accurate diagnostic methods, with CSF culture being the gold standard. In addition, the improvement in the quality of beta-lactam treatment and the greater possibility of prevention due to the increased number and effectiveness of vaccines have contributed to reducing the number of cases and severity of the disease. Nevertheless, despite these advances, this syndrome still presents a high number of mortalities and sequelae.

Update on the Neisseria Macrophage Infectivity Potentiator-Like PPIase Protein.

Neisseria pathogens express a Macrophage Infectivity Potentiator Protein (MIP), which belongs to the FK506 binding protein (FKBP) family of proteins that exhibit peptidyl-prolyl cis/trans isomerase (PPIase) activity. Neisseria MIP proteins are potential candidates for inclusion into vaccines for gonorrhoea caused by N. gonorrhoeae infection, and meningitis/sepsis caused by M. meningitidis infection. Neisseria MIP proteins are also potential targets for directed drug treatments, although this remains relatively unexplored. In this mini-review, we provide an update into the vaccine potential of Neisseria MIP and the few published drug targeting studies, and explore further the diversity of this protein amongst both pathogenic and commensal Neisseria spp.

A Low Virulence Infective Tenosynovitis Triggered by a Neisseria Species.

A persistent infective tenosynovitis, caused by a non-pathogenic Neisseria species and involving the little finger and the thumb of a middle-aged woman, forming a horseshoe-type infection is presented. An extensive volar approach was utilised for excision of the granulomatous synovium and drainage of turbid fluid. Neisseria spp was isolated by tissue microbiology and targeted antibiotic therapy for 6 weeks was required to eradicate infection. The presence of low virulence microorganisms which might act as true pathogens should always be considered as a causative factor leading to persistent infections that require open surgical debridement and washout. Level of Evidence: Level V (Therapeutic).

Pulmonary Dysfunction Augmenting Bacterial Aerosols in Leather Tanneries of Punjab, Pakistan.

BACKGROUND: Particulate matter-associated microbes in the workplace are a burning issue in occupational toxicology. Studies have reported on respiratory infections among tannery cohorts. This study uniquely presents measurements of airborne bacterial concentrations associated with varied particulate-matter sizes, their exposure, and consequent severity in occupational respiratory problems, all for different microenvironments within leather tanneries. METHODS: Analyses included molecular identification of isolates, computation of mass median aerodynamic diameter of aerosols, tannery process-exposure dose (TPED) to bacterial aerosols, and spirometry and symptom assessment of impaired pulmonary function. RESULTS: The highest bacterial concentrations were for rawhide treatment and finishing units, showing 3.6×103 and 3.7×103 CFU/m3, respectively. Identified bacterial species included Ochrobactrum pseudogrignonense, Neisseria bacilliformis, Enterobacter cloacae, Alcaligenes faecalis, Klebsiella pneumoniae, and Corynebacterium spp. Maximum and minimum values of mass median aerodynamic diameter were 8.3 µm and 0.65 µm for buffing and snuffing and production units, respectively. The highest TPED was 1,516.9 CFU/kg for finishing units. Respiratory symptoms in order of incidence were dyspnea > phlegm > cough > wheezing and tachypnea (equivalent). Bronchodilator measurements of FEV1, FVC, and PEF represent decline in lung function. Of 26 patients identified with COPD, most were working in rawhide treatment. CONCLUSION: We conclude that exposure-infection synergy is also a cause of pulmonary ailments and COPD development, rather than the better-known exposure-smoking synergy.

Oral bacteria detection among children with cancer in a tertiary teaching hospital in Kuala Lumpur, Malaysia.

This study sought to determine the prevalence of pathogenic and non-pathogenic bacteria in the oral cavities of children with cancer. There were 68 paediatric patients with cancer who were included in this study. Oral swab samples from the dorsum of tongues and mouth floors of these patients were subjected to culture, staining, and molecular methods to detect the bacteria. The overall prevalence of gram-positive and gram-negative bacteria was 79.4% (54/68; 95% CI = 68.4 - 87.3) and 25% (17/68; 95% CI = 16.2 - 36.4), respectively. Streptococcus salivarius and Streptococcus parasanguinis were the predominant pathogenic grampositive bacteria, while Neisseria subflava and Neisseria perflava were the most common pathogenic gram-negative bacteria. The results revealed that the number of bacteria isolates recovered in patients receiving cancer treatment was higher (55.9%) than those who had not received treatment (16.2%). Therefore, more isolated pathogenic bacteria were observed post-therapy (54.4%). Pathogenic organisms can have significant implications on patient health. Awareness of the types of bacteria inhabiting the oral cavity is essential to predict and prevent dental problems, and their associated systemic complications. Findings on the diversity of oral microflora can also provide a better understanding of the aetiology of oral diseases in paediatric patients receiving cancer treatment.

A new symbiotic lineage related to Neisseria and Snodgrassella arises from the dynamic and diverse microbiomes in sucking lice.

The phylogenetic diversity of symbiotic bacteria in sucking lice suggests that lice have a complex history of symbiont acquisition, loss, and replacement throughout their evolution. These processes have resulted in the establishment of different, phylogenetically distant bacteria as obligate mutualists in different louse groups. By combining metagenomics and amplicon screening across several populations of three louse species (members of the genera Polyplax and Hoplopleura) we describe a novel louse symbiont lineage related to Neisseria and Snodgrassella, and show its independent origin in the two louse genera. While the genomes of these symbionts are highly similar, their respective distributions and status within lice microbiomes indicate that they have different functions and history. In Hoplopleura acanthopus, the Neisseriaceae-related bacterium is a dominant obligate symbiont present across several host populations. In contrast, the Polyplax microbiomes are dominated by the obligate symbiont Legionella polyplacis, with the Neisseriaceae-related bacterium co-occurring only in some samples and with much lower abundance. The results thus support the view that compared to other exclusively blood feeding insects, Anoplura possess a unique capacity to acquire symbionts from diverse groups of bacteria.

The bacterial association with oral cavity and intra-abdominal abscess after gastrectomy.

BACKGROUND: Perioperative oral management has been reported to be effective for preventing postoperative infectious complications. In addition, severe periodontal disease was identified as the significant risk factor for complications after gastrointestinal surgery. We investigated the bacteriological association between the periodontal pocket, stomach mucosa and drainage fluid to determine whether oral bacteria directly cause intra-abdominal infection after gastrectomy. METHODS: Patients who were scheduled to undergo surgery for gastric cancer were prospectively enrolled. We evaluated the similarity of bacterial strains in periodontal pocket, stomach mucosa and fluid from drainage tube. Gingival crevicular fluid and dental plaque were collected from the periodontal pocket and cultured to detect bacteria. Specimens from the resected stomach were collected and used for bacterial culturing. Drainage fluid from the abdominal cavity was also cultured. RESULTS: All of 52 patients were enrolled. In the periodontal pocket, α-Streptococcus spp., Neisseria sp., and Prevotella sp. were mainly detected. Bacterial cultures in the stomach mucosa were positive in 26 cases. In 20 cases (76.9%), the detected strains were the same as those in the periodontal pocket. Six patients had the postoperative intra-abdominal infection after gastrectomy, and the same bacterial strains was detected in both of drainage fluid and periodontal pocket in two patients with severe periodontal disease. CONCLUSIONS: We found the bacteriological association that same strain detected in periodontal pocket, stomach and in intra-abdominal drainage fluid after gastrectomy in patients with periodontal disease.

Screening of Health-Associated Oral Bacteria for Anticancer Properties in vitro.

While extensive literature exists about the role of oral bacterial pathogens like Porphyromonas gingivalis and Fusobacterium nucleatum in oral squamous cell carcinoma (OSCC), the role of health-associated species has been largely unexplored. In this study, we assessed the effect of Streptococcus mitis, Rothia mucilaginosa, Neisseria flavescens, Haemophilus parainfluenzae, Lautropia mirabilis, and Veillonella parvula on proliferation and expression of marker genes (IL-6, TNF-α, MMP3, CD36, CCD1, and NANOG) in OSCC cell lines CAL27, SCC25, and SCC4. Porphyromonas gingivalis was included as a pathogenic control. Both bacterial lysates (3 concentrations) and live cells (3 MOIs) were tested. S. mitis, H. parainfluenzae, and N. flavescens resulted in substantial, dose-dependent reduction of proliferation, which was found to be mediated by H2O2 for the former and intracellular infection in the latter two species. However, only H. parainfluenzae showed differential antiproliferative effect against the cancer cell lines vs. the normal control (TIGKs). In the gene expression assays, the health-associated species mostly downregulated CD36, a gene that plays an important role in tumor growth and metastasis, while P. gingivalis upregulated it. IL6 and TNF expression, on the other hand, was upregulated by almost all species, particularly the Gram-negatives including P. gingivalis. The effect on other genes was less evident and varied significantly by cell line. This exploratory study is the first insight into how health-associated bacteria may interact with OSCC. Further studies to explore whether the observed effects may have implications for the prevention or treatment of oral cancer are warranted.

Neisseria macacae bacteremia: report of two cases with a literature review.

BACKGROUND: Neisseria macacae was discovered in the oral cavity of monkeys in 1983. In humans, it has been isolated from the upper respiratory tract of neutropenic patients. However, only two cases of N. macacae bacteremia have been reported in a 65-year-old man with infective endocarditis and a 5-month-old child with fever and petechiae. There are no reports of infections in cancer patients. Here, we present two cases of N. macacae bacteremia in cancer patients. CASE PRESENTATION: In the first case, a 42-year-old woman who underwent ovarian cancer surgery presented with duodenal invasion associated with multiple lymph node metastasis. N. macacae was isolated from her blood culture and identified using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). In the second case, a 69-year-old woman with a long-standing history of esophagogastric junction cancer presented with fever. She had stage IVB cancer with lung, bone, and multiple lymph node metastasis. The last chemotherapy was administered 5 weeks before N. macacae was detected using MALDI-TOF MS and nitrate test negative. In both cases, transthoracic echography showed no vegetation. Antibiotics were administered for 14 and 13 days in the first and second cases, respectively. In both cases, fever alleviated on day 4 of antibiotic administration. Both patients were discharged after their conditions improved. CONCLUSIONS: This, to our knowledge, is the first report of N. macacae bacteremia in cancer patients. Both patients, mucosal damage was observed in the upper gastrointestinal tract. Therefore, exclusion diagnosis suggested that bacteremia invasion was caused by mucosal rupture in both cases. Both cases responded well to treatment with ß-lactam antibiotics and improved after 2 weeks. Modifying the treatment based on the source of the infection may shorten the treatment period. Therefore, further research on N. macacae bacteremia is necessary. Immunocompromised patients such as those with cancer are susceptible to mucosal damage by unusual bacterial species such as N. macacae despite not having contact with monkeys.

Precise diagnosis of Neisseria macacae infective endocarditis assisted by nanopore sequencing.

Infective endocarditis caused by Neisseria macacae in humans is extremely rare. We presented here a case of N. macacae infective endocarditis in a 61-year-old man with a native aortic valve infection. N. macacae was isolated from blood culture and was detected by nanopore-based metagenomic sequencing in the vegetations. Finally, the patient recovered completely after surgery and antibiotic therapy.

The microbiomes of adenoid and middle ear in children with otitis media with effusion and hypertrophy from a tertiary hospital in China.

INTRODUCTION: Otitis media with effusion (OME) is one of the most common pediatric diseases worldwide. Several studies have analyzed the diversity of the microbiomes found in the middle ear effusions (MEEs) of populations from developed countries. However, no microbiological studies of MEEs from Chinese children with OME have been reported. This study investigated the middle ear and adenoid microbiological profiles of children with OME, and compared the microbial flora of the adenoid between children with and without otitis media. METHODS: MEEs and adenoid swabs were acquired from 15 children undergoing ventilation tube insertion and adenoidectomy. Adenoid swabs from 15 patients with no ear disease were used as controls. Samples were analyzed by 16S rRNA sequencing. Operational taxonomic units (OTUs) abundance information were normalized. Alpha diversity analyses were used to assess the richness and diversity of the microbial community for each sample. Beta diversity analyses were used to determine the inter-group variability between microbiome structure. RESULTS: Based on the mean relative abundance, the MEEs were dominated by Haemophilus (14.75%), Staphylococcus (9.37%) and Halomonas (7.85%), and the bacterial compositions of the adenoids in the OME groups were dominated by Haemophilus (21.87%), Streptococcus (19.65%), and Neisseria (5.8%). The bacterial compositions in the adenoids of the controls were dominated by Haemophilus (15.96%), Streptococcus (13.33%), and Moraxella (12.28%). Alpha diversity analyses showed that there were no significant differences in microbiome richness or diversity between the middle ear effusions (TM) and adenoids (TA) of OME subjects. Adenoid samples from OME patients (TA) and control patients (CA) were also similar. Beta diversity analyses showed that the microbiomes of the adenoids in OME patients were also similar to that of controls. However, the microbiome structure of middle ear effusions was dissimilar to those of the adenoids in OME patients according to beta diversity analyses. CONCLUSIONS: Our results confirmed the microbial diversity of MEEs among Chinese children. However, the dissimilar microbiome composition between samples taken from the surface of the adenoids and from the middle ear effusions challenges the conventional theory that the adenoid serves as a microbial reservoir in children with otitis media with effusion.

Randomized Controlled Study to Evaluate Microbial Ecological Effects of CPP-ACP and Cranberry on Dental Plaque.

INTRODUCTION: Ecological approaches to dental caries prevention play a key role in attaining long-term control over the disease and maintaining a symbiotic oral microbiome. OBJECTIVES: This study aimed to investigate the microbial ecological effects of 2 interventional dentifrices: a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) dentifrice and the same dentifrice supplemented with a polyphenol-rich cranberry extract. METHODS: The interventional toothpastes were compared with each other and with an active control fluoride dentifrice in a double-blinded randomized controlled trial. Real-time quantitative polymerase chain reaction (qPCR) analysis was used to determine changes in the bacterial loads of 14 key bacterial species (8 caries associated and 6 health associated) in the dental plaque of trial participants after they used the dentifrices for 5 to 6 wk. RESULTS: From the baseline to the recall visit, significant differences were observed between the treatment groups in the bacterial loads of 2 caries-associated bacterial species (Streptococcus mutans [P < 0.001] and Veillonella parvula [P < 0.001]) and 3 health-associated bacterial species (Corynebacterium durum [P = 0.008], Neisseria flavescens [P = 0.005], and Streptococcus sanguinis [P < 0.001]). Compared to the fluoride control dentifrice, the CPP-ACP dentifrice demonstrated significant differences for S. mutans (P = 0.032), C. durum (P = 0.007), and S. sanguinis (P < 0.001), while combination CPP-ACP-cranberry dentifrice showed significant differences for S. mutans (P < 0.001), V. parvula (P < 0.001), N. flavescens (P = 0.003), and S. sanguinis (P < 0.001). However, no significant differences were observed in the bacterial load comparisons between the CPP-ACP and combination dentifrices for any of the targeted bacterial species (P > 0.05). CONCLUSIONS: Overall, the results indicate that dentifrices containing CPP-ACP and polyphenol-rich cranberry extracts can influence a species-level shift in the ecology of the oral microbiome, resulting in a microbial community less associated with dental caries (Australian New Zealand Clinical Trial Registry ANZCTR 12618000095268). KNOWLEDGE TRANSFER STATEMENT: The results of this randomized controlled trial indicate that dentifrices containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and polyphenol-rich cranberry extracts were able to beneficially modulate the microbial ecology of dental plaque in a group of high caries-risk patients. This could contribute toward lowering the risk of developing new caries lesions, an important goal sought by patients, clinicians, and policy makers.

Genomic characterization of novel Neisseria species.

Of the ten human-restricted Neisseria species two, Neisseria meningitidis, and Neisseria gonorrhoeae, cause invasive disease: the other eight are carried asymptomatically in the pharynx, possibly modulating meningococcal and gonococcal infections. Consequently, characterizing their diversity is important for understanding the microbiome in health and disease. Whole genome sequences from 181 Neisseria isolates were examined, including those of three well-defined species (N. meningitidis; N. gonorrhoeae; and Neisseria polysaccharea) and genomes of isolates unassigned to any species (Nspp). Sequence analysis of ribosomal genes, and a set of core (cgMLST) genes were used to infer phylogenetic relationships. Average Nucleotide Identity (ANI) and phenotypic data were used to define species clusters, and morphological and metabolic differences among them. Phylogenetic analyses identified two polyphyletic clusters (N. polysaccharea and Nspp.), while, cgMLST data grouped Nspp isolates into nine clusters and identified at least three N. polysaccharea clusters. ANI results classified Nspp into seven putative species, and also indicated at least three putative N. polysaccharea species. Electron microscopy identified morphological differences among these species. This genomic approach provided a consistent methodology for species characterization using distinct phylogenetic clusters. Seven putative novel Neisseria species were identified, confirming the importance of genomic studies in the characterization of the genus Neisseria.