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Bioengineered Jun 2022Periodontitis is a risk factor for the development of oral squamous cell carcinomas (OSCC). Both DNA damage response (DDR) and activation of inflammasomes induced by the...
Periodontitis is a risk factor for the development of oral squamous cell carcinomas (OSCC). Both DNA damage response (DDR) and activation of inflammasomes induced by the microbiome might play important roles in the development of tumors, in relation to genome stability of tumor cells. Herein, we explored whether periodontitis negative-associated bacteria ( and , namely called 'PNB'), which were highly abundant in healthy populations, could inhibit OSCC by promoting genome stability. Firstly, a murine SCC-7 tumor-bearing model that colonized with PNB was designed and used in this study. Then, cyclin D1 was detected by immunohistochemistry. Levels of DDR, NLRP3 inflammasomes and pro-inflammatory cytokines in tumors were detected by RT-qPCR or Western blot. Immune cells in spleens were detected by immunohistochemistry or immunofluorescence. Finally, the anti-cancer activity of PNB was assessed using CCK-8 assays and flow cystometry. Compared with the control, PNB decreased tumor weights from 0.77 ± 0.26 g to 0.42 ± 0.15 g and downregulated the expression of Cyclin D1. PNB activated the DDR by up-regulating γ-H2AX, p-ATR, and p-CHK1. PNB activated NLRP3 inflammasome-mediated pyroptosis via increases of NLRP3, gasdermin D, and mRNA levels of apoptosis-associated speck-like protein, Caspase-1. PNB suppressed the inflammatory response by down-regulating mRNA levels of NF-κΒ and IL-6 in tumors as well as the populations of CD4+ T cells and CD206+ immune cells in spleens. PNB inhibited proliferation and promoted cell death of HSC-3 cells. In conclusion, and showed a 'probiotic bacterial' potential to inhibit OSCC by regulating genome stability.
Topics: Animals; Corynebacterium; Cyclin D1; Genomic Instability; Head and Neck Neoplasms; Inflammasomes; Mice; Mouth Neoplasms; NLR Family, Pyrin Domain-Containing 3 Protein; Neisseria sicca; RNA, Messenger; Squamous Cell Carcinoma of Head and Neck
PubMed: 35734856
DOI: 10.1080/21655979.2022.2078556 -
Revista Chilena de Infectologia :... Oct 2009
Topics: Humans; Neisseria sicca; Neisseriaceae Infections
PubMed: 19915756
DOI: No ID Found -
Pathogens (Basel, Switzerland) Mar 2022Bacteria of the genus are Gram-negative diplococci including both pathogenic and commensal species. We focused on pathogenic and commensal . We have demonstrated that...
Bacteria of the genus are Gram-negative diplococci including both pathogenic and commensal species. We focused on pathogenic and commensal . We have demonstrated that not only , but also induce the secretion of pro-inflammatory cytokines IL-6, TNF-α, and chemokines CXCL8 and CCL20 by infected epithelial cells. However, triggers a lesser effect than does . Furthermore, and invoke distinct effects on the expression of genes (JUNB, FOSB, NFKB1, NFKBIA) encoding protein components of AP-1 and NF-κB transcription factors. We have also shown that the infection of epithelial cells by leads to significant overexpression of the long non-coding RNAs (lncRNAs), including MALAT1, ERICD, and RP11-510N19.5. This effect was not identified for In conclusion, data on the expression of lncRNAs and cytokine secretion in response to spp. exposure indicate new directions for research on -host interactions and can provide further insights into virulence of not only pathogenic, but also commensal spp.
PubMed: 35456069
DOI: 10.3390/pathogens11040394 -
Journal of Bacteriology Nov 2016Neisseria gonorrhoeae (gonococci) and Neisseria meningitidis (meningococci) are human pathogens that cause gonorrhea and meningococcal meningitis, respectively. Both N....
UNLABELLED
Neisseria gonorrhoeae (gonococci) and Neisseria meningitidis (meningococci) are human pathogens that cause gonorrhea and meningococcal meningitis, respectively. Both N. gonorrhoeae and N. meningitidis release a number of small peptidoglycan (PG) fragments, including proinflammatory PG monomers, although N. meningitidis releases fewer PG monomers. The PG fragments released by N. gonorrhoeae and N. meningitidis are generated in the periplasm during cell wall remodeling, and a majority of these fragments are transported into the cytoplasm by an inner membrane permease, AmpG; however, a portion of the PG fragments are released into the extracellular environment through unknown mechanisms. We previously reported that the expression of meningococcal ampG in N. gonorrhoeae reduced PG monomer release by gonococci. This finding suggested that the efficiency of AmpG-mediated PG fragment recycling regulates the amount of PG fragments released into the extracellular milieu. We determined that three AmpG residues near the C-terminal end of the protein modulate AmpG's efficiency. We also investigated the association between PG fragment recycling and release in two species of human-associated nonpathogenic Neisseria: N. sicca and N. mucosa Both N. sicca and N. mucosa release lower levels of PG fragments and are more efficient at recycling PG fragments than N. gonorrhoeae Our results suggest that N. gonorrhoeae has evolved to increase the amounts of toxic PG fragments released by reducing its PG recycling efficiency.
IMPORTANCE
Neisseria gonorrhoeae and Neisseria meningitidis are human pathogens that cause highly inflammatory diseases, although N. meningitidis is also frequently found as a normal member of the nasopharyngeal microbiota. Nonpathogenic Neisseria, such as N. sicca and N. mucosa, also colonize the nasopharynx without causing disease. Although all four species release peptidoglycan fragments, N. gonorrhoeae is the least efficient at recycling and releases the largest amount of proinflammatory peptidoglycan monomers, partly due to differences in the recycling permease AmpG. Studying the interplay between bacterial physiology (peptidoglycan metabolism) and pathogenesis (release of toxic monomers) leads to an increased understanding of how different bacterial species maintain asymptomatic colonization or cause disease and may contribute to efforts to mitigate disease.
Topics: Amino Acid Motifs; Bacterial Proteins; Cell Wall; Membrane Transport Proteins; Neisseria; Neisseria gonorrhoeae; Neisseria meningitidis; Neisseriaceae Infections; Peptidoglycan
PubMed: 27551020
DOI: 10.1128/JB.00437-16 -
FEMS Microbiology Reviews Oct 2000Carbonic anhydrases catalyze the reversible hydration of CO(2) [CO(2)+H(2)Oright harpoon over left harpoon HCO(3)(-)+H(+)]. Since the discovery of this zinc (Zn)... (Review)
Review
Carbonic anhydrases catalyze the reversible hydration of CO(2) [CO(2)+H(2)Oright harpoon over left harpoon HCO(3)(-)+H(+)]. Since the discovery of this zinc (Zn) metalloenzyme in erythrocytes over 65 years ago, carbonic anhydrase has not only been found in virtually all mammalian tissues but is also abundant in plants and green unicellular algae. The enzyme is important to many eukaryotic physiological processes such as respiration, CO(2) transport and photosynthesis. Although ubiquitous in highly evolved organisms from the Eukarya domain, the enzyme has received scant attention in prokaryotes from the Bacteria and Archaea domains and has been purified from only five species since it was first identified in Neisseria sicca in 1963. Recent work has shown that carbonic anhydrase is widespread in metabolically diverse species from both the Archaea and Bacteria domains indicating that the enzyme has a more extensive and fundamental role in prokaryotic biology than previously recognized. A remarkable feature of carbonic anhydrase is the existence of three distinct classes (designated alpha, beta and gamma) that have no significant sequence identity and were invented independently. Thus, the carbonic anhydrase classes are excellent examples of convergent evolution of catalytic function. Genes encoding enzymes from all three classes have been identified in the prokaryotes with the beta and gamma classes predominating. All of the mammalian isozymes (including the 10 human isozymes) belong to the alpha class; however, only nine alpha class carbonic anhydrase genes have thus far been found in the Bacteria domain and none in the Archaea domain. The beta class is comprised of enzymes from the chloroplasts of both monocotyledonous and dicotyledonous plants as well as enzymes from phylogenetically diverse species from the Archaea and Bacteria domains. The only gamma class carbonic anhydrase that has thus far been isolated and characterized is from the methanoarchaeon Methanosarcina thermophila. Interestingly, many prokaryotes contain carbonic anhydrase genes from more than one class; some even contain genes from all three known classes. In addition, some prokaryotes contain multiple genes encoding carbonic anhydrases from the same class. The presence of multiple carbonic anhydrase genes within a species underscores the importance of this enzyme in prokaryotic physiology; however, the role(s) of this enzyme is still largely unknown. Even though most of the information known about the function(s) of carbonic anhydrase primarily relates to its role in cyanobacterial CO(2) fixation, the prokaryotic enzyme has also been shown to function in cyanate degradation and the survival of intracellular pathogens within their host. Investigations into prokaryotic carbonic anhydrase have already led to the identification of a new class (gamma) and future research will undoubtedly reveal novel functions for carbonic anhydrase in prokaryotes.
Topics: Amino Acid Sequence; Archaea; Bacteria; Bacterial Proteins; Carbon Dioxide; Carbonic Anhydrases; Cyanates; Cyanobacteria; Escherichia coli; Methanosarcina; Molecular Sequence Data; Neisseria; Phylogeny; Protein Structure, Secondary; Salmonella typhimurium; Sequence Alignment
PubMed: 10978542
DOI: 10.1111/j.1574-6976.2000.tb00546.x -
Cancer Prevention Research... Jul 2022The microbiome has increasingly been linked to cancer. Little is known about the lung and oral cavity microbiomes in smokers, and even less for electronic cigarette (EC)...
UNLABELLED
The microbiome has increasingly been linked to cancer. Little is known about the lung and oral cavity microbiomes in smokers, and even less for electronic cigarette (EC) users, compared with never-smokers. In a cross-sectional study (n = 28) of smokers, EC users, and never-smokers, bronchoalveolar lavage and saliva samples underwent metatranscriptome profiling to examine associations with lung and oral microbiomes. Pairwise comparisons assessed differentially abundant bacteria species. Total bacterial load was similar between groups, with no differences in bacterial diversity across lung microbiomes. In lungs, 44 bacteria species differed significantly (FDR < 0.1) between smokers/never-smokers, with most decreased in smokers. Twelve species differed between smokers/EC users, all decreased in smokers of which Neisseria sp. KEM232 and Curvibacter sp. AEP1-3 were observed. Among the top five decreased species in both comparisons, Neisseria elongata, Neisseria sicca, and Haemophilus parainfluenzae were observed. In the oral microbiome, 152 species were differentially abundant for smokers/never-smokers, and 17 between smokers/electronic cigarette users, but only 21 species were differentially abundant in both the lung and oral cavity. EC use is not associated with changes in the lung microbiome compared with never-smokers, indicating EC toxicity does not affect microbiota. Statistically different bacteria in smokers compared with EC users and never-smokers were almost all decreased, potentially due to toxic effects of cigarette smoke. The low numbers of overlapping oral and lung microbes suggest that the oral microbiome is not a surrogate for analyzing smoking-related effects in the lung.
PREVENTION RELEVANCE
The microbiome affects cancer and other disease risk. The effects of e-cig usage on the lung microbiome are essentially unknown. Given the importance of lung microbiome dysbiosis populated by oral species which have been observed to drive lung cancer progression, it is important to study effects of e-cig use on microbiome.
Topics: Bacteria; Cross-Sectional Studies; Electronic Nicotine Delivery Systems; Lung; Microbiota; Saliva; Vaping
PubMed: 35667088
DOI: 10.1158/1940-6207.CAPR-21-0601 -
Frontiers in Microbiology 2021The taxonomy of the genus remains confusing, particularly regarding and In 2012, ribosomal multi-locus sequence typing reclassified both as , but data concerning 17...
Confirmation of the Need for Reclassification of and Using Average Nucleotide Identity Blast and Phylogenetic Analysis of Whole-Genome Sequencing: Hinted by Clinical Misclassification of a Strain.
The taxonomy of the genus remains confusing, particularly regarding and In 2012, ribosomal multi-locus sequence typing reclassified both as , but data concerning 17 strains remain available in GenBank. The continuous progress of high-throughput sequencing has facilitated ready accessibility of whole-genome data, promoting vigorous development of average nucleotide identity (ANI) and high-resolution phylogenetic analysis. Here, we report that a isolate, which caused native-valve endocarditis and multiple embolic brain infarcts in a patient with congenital heart disease, was misidentified as by VITEK MS. This isolate was reclassified as by ANI blast (ANIb) and by phylogenetic analysis using whole-genome data yielded by the PacBio Sequel and Illumina NovaSeq PE150 platforms. The confusion evident in the GenBank and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) databases suggests that ( = 13) and ( = 16) in GenBank should be reclassified using ANIb and high-resolution phylogenetic analysis. The whole-genome data of 30 strains (including the clinical isolate) were compared with the data of 27 type strains (including one and two type strains) as a genomic index. In total, 25 (8 originally identified as and 17 originally identified as ) and 7 (1 originally identified as and 6 originally identified as ) strains were reclassified into the and groups, respectively; 1 residual strain was reclassified as . In conclusion, a combination of ANIb and robust phylogenetic analysis reclassified strains originally identified as and into (principally) the group and the group. The misclassified and strains in the GenBank and MALDI-TOF MS databases were supposed to be corrected. Updated genomic classification strategy for originally identified and strains was recommended to be adopted in GenBank.
PubMed: 35281306
DOI: 10.3389/fmicb.2021.780183 -
Infection and Drug Resistance 2023Although commensal species inhabiting mucosal surfaces in the upper respiratory tract (URT) are rarely associated with infections, their presence in the area has been...
BACKGROUND
Although commensal species inhabiting mucosal surfaces in the upper respiratory tract (URT) are rarely associated with infections, their presence in the area has been linked to the development of immunity against . and the source of antibiotic resistance determinants in pathogenic species. in the oropharynx of children is also a predisposing factor for otitis media. As a result, determining the oropharyngeal carriage rate of these commensal species and associated factors among healthy schoolchildren is substantial.
MATERIALS AND METHODS
This community-based cross-sectional study was conducted in Gondar, Northwest Ethiopia, from January to April 2019. A multi-stage and simple random sampling technique were used to select schools and participants, respectively. A total of 524 oropharyngeal swabs were collected using cotton swabs. Modified Thayer-Martin media was used for primary bacterial isolation, and battery of biochemical tests was performed to identify species. For frequencies, descriptive statistics were computed and the logistic regression model was used to see the relationship between dependent and independent variables.
RESULTS
A total of 524 healthy schoolchildren with a mean age of 12.2 ± 2.74 years participated in this study. The overall oropharyngeal carriage rate was 21.8% (114/524). Of these, , . , . , and were identified in 53 (46.5%), 14 (12.3%), 11 (9.6%), and 36 (31.6%) children, respectively. The culture positivity rate was higher at a younger age, which was 8.1%, 11.3%, and 14.9% in ages between 15-18, 11-14, and 7-10, respectively. The oropharyngeal carriage was significantly associated with the number of students per class (>40).
CONCLUSION
There is a higher proportion of carriers of commensal and in Gondar town schoolchildren. The oropharyngeal carriage rate was associated with a crowded classroom. The characterization of non-pathogenic species and in the study area can support the diagnosis of patients suspected of having infections.
PubMed: 36714354
DOI: 10.2147/IDR.S395343 -
Journal of Clinical Microbiology Sep 1992Neisseria meningitidis from various serogroups and two commensal neisseriae (N. sicca and N. perflava) were isolated from 15 patients at various stages of human...
Neisseria meningitidis from various serogroups and two commensal neisseriae (N. sicca and N. perflava) were isolated from 15 patients at various stages of human immunodeficiency virus infection in this clinical and bacteriological study. The cases were grouped into the following three classes: (i) infections with an N. meningitidis strain of a serogroup known to be pathogenic (A, B, or C) and apparently independent of the human immunodeficiency virus infection, (ii) infections with a N. meningitidis strain of a serogroup which is normally either commensal or poorly pathogenic (serogroups Y, X, Z, and Z,29E), (iii) pulmonary and disseminated infections occurring in the course of the clinical evolutionary stage of AIDS, in two cases of which commensal neisseriae (N. sicca and N. perflava) were isolated from blood cultures.
Topics: Acquired Immunodeficiency Syndrome; Adolescent; Adult; Bacteremia; Female; France; HIV Infections; Humans; Male; Meningitis; Microbial Sensitivity Tests; Neisseria; Neisseria meningitidis; Neisseriaceae Infections; Respiratory Tract Diseases; Risk Factors; Serotyping
PubMed: 1400993
DOI: 10.1128/jcm.30.9.2290-2294.1992 -
Scientific Reports Jul 2019Acetaldehyde is known to be carcinogenic and produced by oral bacteria. Thus, bacterial acetaldehyde production might contribute to oral cancer. Therefore, we examined...
Acetaldehyde is known to be carcinogenic and produced by oral bacteria. Thus, bacterial acetaldehyde production might contribute to oral cancer. Therefore, we examined bacterial acetaldehyde production from ethanol and glucose under various conditions mimicking the oral cavity and clarified the metabolic pathways responsible for bacterial acetaldehyde production. Streptococcus mitis, S. salivarius, S. mutans, Neisseria mucosa and N. sicca were used. The bacterial metabolism was conducted at pH 5.0-8.0 under aerobic and anaerobic conditions. The production of acetaldehyde and organic acids was measured with gas chromatography and HPLC, respectively. Bacterial enzymes were also assessed. All of the bacteria except for S. mutans exhibited their greatest acetaldehyde production from ethanol at neutral to alkaline pH under aerobic conditions. S. mutans demonstrated the greatest acetaldehyde from glucose under anaerobic conditions, although the level was much lower than that from ethanol. Alcohol dehydrogenase and NADH oxidase were detected in all of the bacteria. This study revealed that oral indigenous bacteria, Streptococcus and Neisseria can produce acetaldehyde, and that such acetaldehyde production is affected by environmental conditions. It was suggested that alcohol dehydrogenase and NADH oxidase are involved in ethanol-derived acetaldehyde production and that the branched-pathway from pyruvate is involved in glucose-derived acetaldehyde production.
Topics: Acetaldehyde; Alcohol Dehydrogenase; Ethanol; Glucose; Multienzyme Complexes; NADH, NADPH Oxidoreductases; Neisseria; Oxygen; Streptococcus
PubMed: 31320675
DOI: 10.1038/s41598-019-46790-9