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RNA Biology Jan 2023Cas9 nucleases are widely used for genome editing and engineering. Cas9 enzymes encoded by CRISPR-Cas defence systems of various prokaryotic organisms possess different...
Cas9 nucleases are widely used for genome editing and engineering. Cas9 enzymes encoded by CRISPR-Cas defence systems of various prokaryotic organisms possess different properties such as target site preferences, size, and DNA cleavage efficiency. Here, we biochemically characterized CoCas9 from , a bacterium that inhabits the oral cavity of humans and contributes to plaque formation on teeth. CoCas9 recognizes a novel 5'-NRRWC-3' PAM and efficiently cleaves DNA . Functional characterization of CoCas9 opens ways for genetic engineering of using its endogenous CRISPR-Cas system. The novel PAM requirement makes CoCas9 potentially useful in genome editing applications.
Topics: Humans; CRISPR-Associated Protein 9; CRISPR-Cas Systems; Gene Editing; Capnocytophaga
PubMed: 37743659
DOI: 10.1080/15476286.2023.2256578 -
The Bulletin of Tokyo Dental College Jun 2021Capnocytophaga ochracea possesses a type-IX secretion system that exports proteins which have a gliding motility-associated C-terminal (CTD) domain. This system is found...
Capnocytophaga ochracea possesses a type-IX secretion system that exports proteins which have a gliding motility-associated C-terminal (CTD) domain. This system is found in several species of the Bacteroidetes phylum. Hyalin, a large protein encoded by Coch_0033 in C. ochracea ATCC 27872, has a CTD domain and is posited to be involved in quorum sensing according to the database of the Kyoto Encyclopedia of Genes and Genomes. This suggests that it plays a role in biofilm formation via interbacterial communication. The aim of this study was to investigate the potential role of the hyalin-like protein coded by the Coch_0033 gene in gliding and biofilm formation of C. ochracea. A hyalin-like protein-deficient mutant strain of C. ochracea, designated mutant WR-1, was constructed through insertion of the ermF-ermAM cassette into the target gene. The spreading feature at the edge of the colony was lost in the mutant strain. Crystal violet and confocal laser scanning microscopy revealed no difference between the quantity of biofilm organized by the mutant and that organized by the wild-type strain. These data suggest that the hyalin-like protein encoded by the Coch_0033 gene is indeed involved in C. ochracea gliding activity.
Topics: Bacterial Proteins; Bacteroidetes; Biofilms; Capnocytophaga; Hyalin
PubMed: 33994426
DOI: 10.2209/tdcpublication.2020-0051 -
The American Journal of Case Reports Jun 2017BACKGROUND Capnocytophaga ochracea is a gram-negative anaerobic organism commonly found in human oral flora. It is characteristically sensitive to beta-lactams and...
BACKGROUND Capnocytophaga ochracea is a gram-negative anaerobic organism commonly found in human oral flora. It is characteristically sensitive to beta-lactams and resistant to aminoglycosides. CASE REPORT A 23-year-old woman presented with lower abdominal pain and was admitted for premature labor at 24-weeks of gestation. At presentation, the cervix was closed and the membrane was intact; however, contractions continued, the membrane subsequently ruptured before receiving any steroids or magnesium, and the mother gave birth to a 540-gram female baby. At birth, Apgar scores were 1 at 5 minutes, 1 at 10 minutes, and 2 at 15 minutes. On the fifth day of life, the blood culture grew Capnocytophaga species. Consequently, Cefotaxime was started and ampicillin continued for a total of 14 days; however, on the 6th day, the head ultrasound showed grade 4 intraventricular hemorrhage and a Do Not Resuscitate (DNR) order was placed in the chart. The patient's health continued to deteriorate, having multiple episodes of bradycardia and desaturation until cardiac arrest on the 17th day. CONCLUSIONS Capnocytophaga ochracea was isolated from the blood culture of a preterm neonate. It was thought to be the cause of the premature labor and subsequent neonatal septicemia. This case report suggests that the prevalence of Capnocytophaga infections is most likely underestimated and that additional premature labors and abortions could have been caused by Capnocytophaga infections that were never detected. Hence, more studies are needed to investigate the route of transmission.
Topics: Capnocytophaga; Cerebral Intraventricular Hemorrhage; Fatal Outcome; Female; Gram-Negative Bacterial Infections; Heart Arrest; Humans; Infant, Newborn; Infant, Premature, Diseases; Neonatal Sepsis; Obstetric Labor, Premature; Pregnancy
PubMed: 28620153
DOI: 10.12659/ajcr.903824 -
Applied and Environmental Microbiology Jan 2016Capnocytophaga ochracea is a Gram-negative, rod-shaped bacterium that demonstrates gliding motility when cultured on solid agar surfaces. C. ochracea possesses the...
Capnocytophaga ochracea is a Gram-negative, rod-shaped bacterium that demonstrates gliding motility when cultured on solid agar surfaces. C. ochracea possesses the ability to form biofilms; however, factors involved in biofilm formation by this bacterium are unclear. A type IX secretion system (T9SS) in Flavobacterium johnsoniae was shown to be involved in the transport of proteins (e.g., several adhesins) to the cell surface. Genes orthologous to those encoding T9SS proteins in F. johnsoniae have been identified in the genome of C. ochracea; therefore, the T9SS may be involved in biofilm formation by C. ochracea. Here we constructed three ortholog-deficient C. ochracea mutants lacking sprB (which encodes a gliding motility adhesin) or gldK or sprT (which encode T9SS proteins in F. johnsoniae). Gliding motility was lost in each mutant, suggesting that, in C. ochracea, the proteins encoded by sprB, gldK, and sprT are necessary for gliding motility, and SprB is transported to the cell surface by the T9SS. For the ΔgldK, ΔsprT, and ΔsprB strains, the amounts of crystal violet-associated biofilm, relative to wild-type values, were 49%, 34%, and 65%, respectively, at 48 h. Confocal laser scanning and scanning electron microscopy revealed that the biofilms formed by wild-type C. ochracea were denser and bacterial cells were closer together than in those formed by the mutant strains. Together, these results indicate that proteins exported by the T9SS are key elements of the gliding motility and biofilm formation of C. ochracea.
Topics: Bacterial Proteins; Bacterial Secretion Systems; Biofilms; Capnocytophaga; Gene Knockout Techniques; Locomotion
PubMed: 26729712
DOI: 10.1128/AEM.03452-15 -
Infection and Immunity Dec 1979When examined by both light and scanning electron microscopy, Capnocytophaga gingivalis, C. sputigena, and C. ochracea displayed three distinct growth zones: the...
When examined by both light and scanning electron microscopy, Capnocytophaga gingivalis, C. sputigena, and C. ochracea displayed three distinct growth zones: the original streak, an intermediate zone, and the advancing edge, or halo zone. On Trypticase (BBL Microbiology Systems)-soy-blood agar, the cells translocated by gliding. C. gingivalis and C. sputigena formed large, irregular isolated colonies, while C. ochracea formed a more confluent cell mass. The cells within the streak zone and in most of the intermediate zone were heaped into mounds, with the individual cells displaying a definite flow pattern, the latter characteristic of C. sputigena and C. gingivalis. The halo zone consisted of tracks of cells which appeared to have translocated back upon themselves, or were restricted in their outward movements by adjacent cells. Also present within the halo zone were small aggregates of cells, referred to as pioneer colonies. The cell surfaces of C. gingivalis and C. ochracea were smooth and free of any apparent extracellular material, whereas C. sputigena was covered with a thick amorphous material, as well as long, thick, cell surface-associated fibrils.
Topics: Bacteroidetes; Humans; Microscopy, Electron, Scanning; Mouth; Movement
PubMed: 528052
DOI: 10.1128/iai.26.3.1146-1158.1979 -
Journal of Oral and Maxillofacial... 2022are facultative anaerobic Gram-negative bacilli and recognized as opportunistic pathogens of various extraoral infections. Only a few studies attempted to identify all...
Comparison of culture and polymerase chain reaction-restriction fragment length polymorphism for identification of various species from subgingival plaque samples of healthy and periodontally diseased individuals.
INTRODUCTION
are facultative anaerobic Gram-negative bacilli and recognized as opportunistic pathogens of various extraoral infections. Only a few studies attempted to identify all the seven species of phenotypically and genotypically in healthy individuals and patients with chronic periodontitis. Studies to determine the prevalence of in subgingival plaque samples from healthy individuals, chronic gingivitis and periodontitis among Indian population are lacking.
AIM
The aim of this study was to identify and compare the presence of species phenotypically through microbial culture and biochemical tests and genotypically through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in subgingival plaque of healthy individuals and patients with chronic gingivitis and chronic periodontitis.
MATERIALS AND METHODS
A total of 300 subjects, 100 each with gingivitis, periodontitis and periodontally healthy gingiva subjected, were included. Subgingival plaque was collected and was cultured for phenotypic identification (microbial culture and biochemical test), and for genotypic identification, DNA extraction was done and PCR-RFLP analysis was performed to identify the genus and also to identify different species of .
RESULTS
Of 300 individuals, species were identified from 237 (79%) individuals by PCR and 82 (27.33%) by culture. The prevalence of was found to be higher with both the methods followed by and . , and were isolated only by culture with very low prevalence that is 1.33%, 1.33% and 0.66%, respectively. We could not get any isolate of by any of the two methods.
CONCLUSION
species could be found in gingival sulci as well as periodontal pockets and can be detected by culture and PCR-RFLP. However, higher prevalence of these species in healthy compared to disease requires further analysis to determine their role in healthy and diseased periodontium.
PubMed: 35968170
DOI: 10.4103/jomfp.jomfp_172_21 -
Infection and Immunity Jan 2002Toll-like receptors (TLRs) 2 and 4 have recently been identified as possible signal transducers for various bacterial ligands. To investigate the roles of TLRs in the...
Toll-like receptors (TLRs) 2 and 4 have recently been identified as possible signal transducers for various bacterial ligands. To investigate the roles of TLRs in the recognition of periodontopathic bacteria by the innate immune system, a Chinese hamster ovary (CHO) nuclear factor-kappaB (NF-kappaB)-dependent reporter cell line, 7.7, which is defective in both TLR2- and TLR4-dependent signaling pathways was transfected with human CD14 and TLRs. When the transfectants were exposed to freeze-dried periodontopathic bacteria, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Capnocytophaga ochracea, and Fusobacterium nucleatum, and a non-oral bacterium, Escherichia coli, all species of the bacteria induced NF-kappaB-dependent CD25 expression in 7.7/huTLR2 cells. Although freeze-dried A. actinomycetemcomitans, F. nucleatum, and E. coli also induced CD25 expression in 7.7/huTLR4 cells, freeze-dried P. gingivalis did not. Similarly, lipopolysaccharides (LPS) extracted from A. actinomycetemcomitans, F. nucleatum, and E. coli induced CD25 expression in 7.7/huTLR4 cells, but LPS from P. gingivalis and C. ochracea did not. Furthermore, LPS from P. gingivalis and C. ochracea attenuated CD25 expression in 7.7/huTLR4 cells induced by repurified LPS from E. coli. LPS from P. gingivalis and C. ochracea also inhibited the secretion of interleukin-6 (IL-6) from U373 cells, the secretion of IL-1beta from human peripheral blood mononuclear cells, and ICAM-1 expression in human gingival fibroblasts induced by repurified LPS from E. coli. These findings indicated that LPS from P. gingivalis and C. ochracea worked as antagonists for human TLR4. The antagonistic activity of LPS from these periodontopathic bacteria may be associated with the etiology of periodontal diseases.
Topics: Aggregatibacter actinomycetemcomitans; Animals; CHO Cells; Capnocytophaga; Cells, Cultured; Cricetinae; Drosophila Proteins; Escherichia coli; Freeze Drying; Fusobacterium nucleatum; Gingiva; Humans; Intercellular Adhesion Molecule-1; Interleukin-1; Interleukin-6; Leukocytes, Mononuclear; Lipopolysaccharides; Membrane Glycoproteins; Periodontium; Porphyromonas gingivalis; Receptors, Cell Surface; Species Specificity; Toll-Like Receptor 2; Toll-Like Receptor 4; Toll-Like Receptors
PubMed: 11748186
DOI: 10.1128/IAI.70.1.218-225.2002 -
PloS One 2016Capnocytophaga ochracea is present in the dental plaque biofilm of patients with periodontitis. Biofilm cells change their phenotype through quorum sensing in response...
Capnocytophaga ochracea is present in the dental plaque biofilm of patients with periodontitis. Biofilm cells change their phenotype through quorum sensing in response to fluctuations in cell-population density. Quorum sensing is mediated by auto-inducers (AIs). AI-2 is involved in intercellular signaling, and production of its distant precursor is catalyzed by LuxS, an enzyme involved in the activated methyl cycle. Our aim was to clarify the role of LuxS in biofilm formation by C. ochracea. Two luxS-deficient mutants, TmAI2 and LKT7, were constructed from C. ochracea ATCC 27872 by homologous recombination. The mutants produced significantly less AI-2 than the wild type. The growth rates of these mutants were similar to that of the wild-type in both undiluted Tryptic soy broth and 0.5 × Tryptic soy broth. However, according to crystal violet staining, they produced significantly less biofilm than the wild type. Confocal laser scanning microscopy and scanning electron microscopy showed that the biofilm of the TmAI2 strain had a rougher structure than that of the wild type. Complementation of TmAI-2 with extrinsic AI-2 from the culture supernatant of wild-type strain did not restore biofilm formation by the TmAI2 strain, but complementation of LKT7 strain with luxS partially restored biofilm formation. These results indicate that LuxS is involved in biofilm formation by C. ochracea, and that the attenuation of biofilm formation by the mutants is likely caused by a defect in the activated methyl cycle rather than by a loss of AI-2.
Topics: Bacterial Proteins; Biofilms; Capnocytophaga; Carbon-Sulfur Lyases; Homologous Recombination; Microscopy, Confocal; Microscopy, Electron, Scanning; Mutation
PubMed: 26800339
DOI: 10.1371/journal.pone.0147114 -
JDR Clinical and Translational Research Apr 2023Markers of poor oral health are associated with impaired cognition and higher risk of Alzheimer disease (AD) and thus may help predict AD.
INTRODUCTION
Markers of poor oral health are associated with impaired cognition and higher risk of Alzheimer disease (AD) and thus may help predict AD.
OBJECTIVES
The aim of this study was to evaluate the cross-sectional association between empirically derived groups of 19 IgG antibodies against periodontal microorganisms and cognition in middle-aged and older adults.
METHODS
The study population consisted of participants of the third National Health and Nutrition Examination Survey (NHANES III) (1988 to 1994), who were 60 y and older, among whom cognition and IgG antibodies against 19 periodontal microorganisms were measured ( = 5,162).
RESULTS
In multivariable quantile regression analyses, the Orange-Red (Prevotella melaninogenica, Prevotella intermedia, Prevotella nigrescens, Porphyromonas gingivalis) and Yellow-Orange (Staphylococcus intermedius, Streptococcus oralis, Streptococcus mutans, Fusobacterium nucleatum, Peptostreptococcus micros, Capnocytophaga ochracea) cluster scores were negatively associated with cognition. A 1-unit higher cluster score for the Orange-Red cluster was associated on average with a lower cognitive score (β for 30th quantile = -0.2640; 95% confidence interval [CI], -0.3431 to -0.1848). Similarly, a 1-unit higher score for the Yellow-Orange cluster was associated with a lower cognitive score (β for 30th quantile = -0.2445; 95% CI, -0.3517 to -0.1372).
CONCLUSION
Groups of IgG antibodies against periodontal microorganisms were associated with lower cognition among free living adults 60 years and older, who were previously undiagnosed with cognitive impairment. Though poor oral health precedes the development of dementia and AD, oral health information is currently not used, to our knowledge, to predict dementia or AD risk. Combining our findings with current algorithms may improve risk prediction for dementia and AD.
KNOWLEDGE TRANSLATION STATEMENT
IgG antibodies against periodontal microorganisms were associated with lower cognition among adults 60 years and older previously undiagnosed with cognitive impairment. Periodontal disease may predict cognition among older adults.
Topics: Cross-Sectional Studies; Dementia; Cognition; Immunoglobulin G; Periodontitis; Periodontium; Oral Health; Humans; Male; Female; Middle Aged; Aged; Aged, 80 and over
PubMed: 35139675
DOI: 10.1177/23800844211072784 -
Infection and Immunity Mar 1980Cell suspensions of Capnocytophaga ochracea incorporated [14C]NaHCO3 into a major four-carbon fermentation product, succinate, and cell-free extracts from this organism...
Cell suspensions of Capnocytophaga ochracea incorporated [14C]NaHCO3 into a major four-carbon fermentation product, succinate, and cell-free extracts from this organism contained high levels of phosphoenolpyruvate carboxykinase (PEPCK). PEPCK is the major, if not the only, CO2(HCO-3)-fixing enzyme in C. ochracea since cell-free extracts were devoid of pyruvate-dependent and other phosphoenolpyruvate (PEP)-dependent CO2(HCO-3)-fixing enzymes. The reaction products of the enzyme, which was partially purified by diethylaminoethylcellulose column chromatography, were identified as adenosine 5'-triphosphate (ATP) and oxalacetate. The enzyme showed maximum activity when manganese (Mn2+) was the divalent cation in the incubation mixture, and it had an absolute requirement for the nucleoside 5-'diphosphate adenosine 5'-diphosphate (ADP). PEPCK showed a sigmoidal kinetic response to the Mn2+ concentration and homotropic interactions in its kinetic responses to each of its three substrates PEP, ADP, and CO2(HCO-3). The (S)0.5v values for Mn2+, PEP, ADP, and CO2(CHO-3) were approximately 0.08, 0.3, 0.1, and 10 mM, respectively, and Hill coefficients for these same ligands were 2.60, 1.7, 1.9, and 3.0, respectively. In addition, C. ochracea PEPCK is under metabolic control by the nucleoside -5'-triphosphate ATP, and it also showed a sigmoidal kinetic response to this allosteric effector. The Hill coefficient for ATP was 2.70.
Topics: Adenosine Diphosphate; Adenosine Triphosphate; Bicarbonates; Carbon Dioxide; Cations, Divalent; Cytophagaceae; Glucose; Kinetics; Phosphoenolpyruvate; Phosphoenolpyruvate Carboxykinase (GTP); Succinates
PubMed: 6769807
DOI: 10.1128/iai.27.3.756-766.1980