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Frontiers in Cellular and Infection... 2022Periodontitis and rheumatoid arthritis (RA) are two widespread chronic inflammatory diseases with a previously suggested association. The objective of the current study...
OBJECTIVES
Periodontitis and rheumatoid arthritis (RA) are two widespread chronic inflammatory diseases with a previously suggested association. The objective of the current study was to compare the oral microbial composition and host´s inflammatory mediator profile of saliva samples obtained from subjects with periodontitis, with and without RA, as well as to predict biomarkers, of bacterial pathogens and/or inflammatory mediators, for classification of samples associated with periodontitis and RA.
METHODS
Salivary samples were obtained from 53 patients with periodontitis and RA and 48 non-RA with chronic periodontitis. The microbial composition was identified using 16S rRNA gene sequencing and compared across periodontitis patients with and without RA. Levels of inflammatory mediators were determined using a multiplex bead assay, compared between the groups and correlated to the microbial profile. The achieved data was analysed using PCoA, DESeq2 and two machine learning algorithms, OPLS-DA and sPLS-DA.
RESULTS
Differential abundance DESeq2 analyses showed that the four most highly enriched (log2 FC >20) amplicon sequence variants (ASVs) in the non-RA periodontitis group included sp., sp., sp., and sp. whereas sp., sp., sp., and were the most highly enriched ASVs (log2 FC >20) in the RA group. OPLS-DA with log2 FC analyses demonstrated that the top ASVs with the highest importance included sp. having a positive correlation with non-RA group, and seven ASVs belonging to , sp., , , spp. and with a positive correlation with RA group. Among the detected inflammatory mediators in saliva samples, TWEAK/TNFSF12, IL-35, IFN-α2, pentraxin-3, gp130/sIL6Rb, sIL-6Ra, IL-19 and sTNF-R1 were found to be significantly increased in patients with periodontitis and RA compared to non-RA group with periodontitis. Moreover, correlations between ASVs and inflammatory mediators using sPLS-DA analysis revealed that TWEAK/TNFSF12, pentraxin-3 and IL-19 were positively correlated with the ASVs sp., , sp., and sp.
CONCLUSION
Our results suggest that the combination of microbes and host inflammatory mediators could be more efficient to be used as a predictable biomarker associated with periodontitis and RA, as compared to microbes and inflammatory mediators alone.
Topics: Arthritis, Rheumatoid; Chronic Periodontitis; Humans; Inflammation Mediators; Microbiota; RNA, Ribosomal, 16S
PubMed: 35360114
DOI: 10.3389/fcimb.2022.841139 -
European Journal of Biochemistry Feb 1993The functional properties of the major outer-membrane protein of Acidovorax delafieldii, the anion-selective porin Omp34, were investigated in artificial membranes....
The functional properties of the major outer-membrane protein of Acidovorax delafieldii, the anion-selective porin Omp34, were investigated in artificial membranes. Detergent-solubilized porin incorporates into the membrane in a undirectional orientation solely determined by protein features. This enabled us to characterize the vectorial properties of the porin channels. Omp34 is electrostatically asymmetric regarding both the ion conductivity of a single trimer and the macroscopic ion conductance of multiple porin molecules. Voltage-dependent closing occurred at negative potentials; 50% of the channels were already closed at -10 mV (switching voltage). Our experimental results suggest that protein charges situated on flexible parts inside the channel are involved in the gating mechanism. A simple model is proposed illustrating the mechanism of voltage-dependent opening and closing of the porin channels. This model explains the functional characteristics of Omp34 and the dependence of the switching voltage on the electrolyte concentration in particular. Further factors influencing voltage gating include the buffer concentration as well as the technique used for membrane formation. Altogether these factors may explain the relatively high voltages needed to obtain voltage gating with other porins.
Topics: Bacterial Outer Membrane Proteins; Hydrogen-Ion Concentration; Ion Channel Gating; Ion Channels; Lipid Bilayers; Porins; Pseudomonas
PubMed: 7680309
DOI: 10.1111/j.1432-1033.1993.tb17642.x -
Analytical and Bioanalytical Chemistry Jan 2022Human activities have greatly increased the input of reactive nitrogen species into the environment and disturbed the balance of the global N cycle. This imbalance may...
Human activities have greatly increased the input of reactive nitrogen species into the environment and disturbed the balance of the global N cycle. This imbalance may be offset by bacterial denitrification, an important process in maintaining the ecological balance of nitrogen. However, our understanding of the activity of mixotrophic denitrifying bacteria is not complete, as most research has focused on heterotrophic denitrification. The aim of this study was to investigate substrate preferences for two mixotrophic denitrifying bacterial strains, Acidovorax delafieldii and Hydrogenophaga taeniospiralis, under heterotrophic, autotrophic or mixotrophic conditions. This complex analysis was achieved by simultaneous identification and quantification of H, O, CO, N, N and NO in course of the denitrification process with help of cavity-enhanced Raman spectroscopic (CERS) multi-gas analysis. To disentangle electron donor preferences for both bacterial strains, microcosm-based incubation experiments under varying substrate conditions were conducted. We found that Acidovorax delafieldii preferentially performed heterotrophic denitrification in the mixotrophic sub-experiments, while Hydrogenophaga taeniospiralis preferred autotrophic denitrification in the mixotrophic incubation. These observations were supported by stoichiometric calculations. The results demonstrate the prowess of advanced Raman multi-gas analysis to study substrate use and electron donor preferences in denitrification, based on the comprehensive quantification of complex microbial gas exchange processes.
Topics: Bacteria; Bioreactors; Denitrification; Electrons; Humans; Nitrates; Nitrogen; Spectrum Analysis, Raman
PubMed: 34297136
DOI: 10.1007/s00216-021-03541-y -
Scientific Reports Sep 2017Bacteria are essential in arsenic cycling. However, few studies have addressed 16S rRNA and arsenic-related functional gene diversity in long-term arsenic-contaminated...
Bacteria are essential in arsenic cycling. However, few studies have addressed 16S rRNA and arsenic-related functional gene diversity in long-term arsenic-contaminated tropical sediment. Here, using culture-based, metagenomic and computational approaches, we describe the diversity of bacteria, genes and enzymes involved in AsIII and AsV transformation in freshwater sediment and in anaerobic AsIII- and AsV-enrichment cultures (ECs). The taxonomic profile reveals significant differences among the communities. Arcobacter, Dechloromonas, Sedimentibacter and Clostridium thermopalmarium were exclusively found in ECs, whereas Anaerobacillus was restricted to AsV-EC. Novel taxa that are both AsV-reducers and AsIII-oxidizers were identified: Dechloromonas, Acidovorax facilis, A. delafieldii, Aquabacterium, Shewanella, C. thermopalmarium and Macellibacteroides fermentans. Phylogenic discrepancies were revealed among the aioA, arsC and arrA genes and those of other species, indicating horizontal gene transfer. ArsC and AioA have sets of amino acids that can be used to assess their functional and structural integrity and familial subgroups. The positions required for AsV reduction are conserved, suggesting strong selective pressure for maintaining the functionality of ArsC. Altogether, these findings highlight the role of freshwater sediment bacteria in arsenic mobility, and the untapped diversity of dissimilatory arsenate-reducing and arsenate-resistant bacteria, which might contribute to arsenic toxicity in aquatic environments.
Topics: Anaerobiosis; Arsenic; Bacteria; Biotransformation; Cluster Analysis; DNA, Bacterial; DNA, Ribosomal; Enzymes; Fresh Water; Genetic Variation; Geologic Sediments; Metabolic Networks and Pathways; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Water Pollutants, Chemical
PubMed: 28894204
DOI: 10.1038/s41598-017-11548-8 -
Journal of Bacteriology Jul 1991The major outer membrane protein (Omp34) of Acidovorax delafieldii (formerly Pseudomonas delafieldii) was purified to homogeneity and was characterized biochemically and...
The major outer membrane protein (Omp34) of Acidovorax delafieldii (formerly Pseudomonas delafieldii) was purified to homogeneity and was characterized biochemically and functionally. The polypeptide has an apparent molecular weight (Mr) of 34,000, and it forms stable oligomers at pH 9.0 in the presence of 10% octylpolyoxyethylene or 2% lithium dodecyl sulfate below 70 degrees C. The intact protein has a characteristic secondary structure composition, as revealed by Fourier transforming infrared spectroscopy (about 60% beta sheet). These features and the amino acid composition are typical for porins. The purified Omp34 is associated with 1 to 2 mol of lipopolysaccharide per mol of the monomer. Pore-forming activity was demonstrated with lipid bilayer experiments. Single-channel and selectivity measurements showed that the protein forms highly anion-selective channels. The unusual dependence of the single-channel conductance on salt concentration suggests that the porin complexes bear positive surface charges, accumulating negatively charged counterions at the pore mouth.
Topics: Bacterial Outer Membrane Proteins; Ion Channels; Lipid Bilayers; Membrane Potentials; Molecular Weight; Porins; Protein Conformation; Pseudomonas; Salts
PubMed: 1712013
DOI: 10.1128/jb.173.13.4182-4187.1991 -
Journal of Clinical Microbiology Nov 2001Ten strains of Lautropia mirabilis (ATCC 51599(T) and nine phenotypically similar clinical isolates) were examined for cellular fatty acid (CFA) composition to evaluate...
Ten strains of Lautropia mirabilis (ATCC 51599(T) and nine phenotypically similar clinical isolates) were examined for cellular fatty acid (CFA) composition to evaluate their chemical relatedness to known bacterial species and groups. The CFAs were liberated from whole cells by base hydrolysis, methylated, and analyzed by gas-liquid chromatography. CFA profiles were generated by using a commericial software package (MIDI, Newark, Del.). All strains tested had an identical CFA profile characterized by major amounts of 16:1omega7c (41%) and 16:0 (44%); smaller amounts (1 to 4%) of 3-OH-10:0, 12:0, 14:0, 15:0, and 18:1 omega7c; trace amounts (<1%) of 10:0, 18:2 and 18:0; and no cyclopropane acids. This profile was similar to the CFA profiles of Acidovorax delafieldii, Comamonas terrigena, and strains of an unclassified Centers for Disease Control group designated weak oxidizer group 1. CFA analysis, when supplemented by phenotypic characterization, is useful for the identification of L. mirabilis isolates.
Topics: Bacterial Typing Techniques; Betaproteobacteria; Fatty Acids; Gram-Negative Bacterial Infections; Humans
PubMed: 11682548
DOI: 10.1128/JCM.39.11.4160-4162.2001 -
Journal of Applied Microbiology 2003This study investigated the influence of water chemistry on copper solvation (cuprosolvency) by pure culture biofilms of heterotrophic bacteria isolated from copper...
AIMS
This study investigated the influence of water chemistry on copper solvation (cuprosolvency) by pure culture biofilms of heterotrophic bacteria isolated from copper plumbing.
METHODS AND RESULTS
Heterotrophic bacteria isolated from copper plumbing biofilms including Acidovorax delafieldii, Flavobacterium sp., Corynebacterium sp., Pseudomonas sp. and Stenotrophomonas maltophilia were used in laboratory coupon experiments to assess their potential for cuprosolvency. Sterile copper coupons were exposed to pure cultures of bacteria to allow biofilm formation and suspended in drinking waters with different chemical compositions. Sterile coupons not exposed to bacteria were used as controls. After 5 days of incubation, copper release and biofilm accumulation was quantified. The results demonstrated that cuprosolvency in the control experiments was influenced by water pH, total organic carbon (TOC) and conductivity. Cuprosolvency in the presence of biofilms correlated with the chemical composition of the water supplies particularly pH, Langeliers Index, chloride, alkalinity, TOC and soluble phosphate concentrations.
CONCLUSIONS
The results suggest water quality may influence cuprosolvency by biofilms present within copper plumbing pipes.
SIGNIFICANCE AND IMPACT OF THE STUDY
The potential for water chemistry to influence cuprosolvency by biofilms may contribute to the sporadic nature of copper corrosion problems in distribution systems.
Topics: Bacteria; Biofilms; Carbon; Copper; Corrosion; Corynebacterium; Electric Conductivity; Flavobacterium; Hydrogen-Ion Concentration; Pseudomonas; Solvents; Stenotrophomonas maltophilia; Water; Water Microbiology; Water Pollutants, Chemical
PubMed: 12588559
DOI: 10.1046/j.1365-2672.2003.01857.x -
Biotechnology Reports (Amsterdam,... Dec 2019In this study, after evaluating the degradation activity of enriched cultures from four crude oil-contaminated soils in mineral salt medium, the most efficient ones were...
In this study, after evaluating the degradation activity of enriched cultures from four crude oil-contaminated soils in mineral salt medium, the most efficient ones were selected for further studies. The chemical analysis of cell-free extract containing phenanthrene by HPLC suggested the superior enriched culture was able to degrade 87.66% of phenanthrene at the concentration of 40 mg L-1 within 10 days. This experiment was done under optimal conditions (37 °C, 10% salinity, and pH around 7 to 7.5). The 16S rRNA sequencing of isolates from this superior enriched culture indicated the highest similarity to (Q-SH3), (Q-SH12), and (Q-SH14). After biodegradation of phenanthrene in liquid medium, the extracts were analyzed to measure barley and alfalfa germination. Results showed a lower level of toxicity to the seeds, hence this enriched culture could be used for bioremediation of saline environments contaminated by phenanthrene and other similar compounds.
PubMed: 31763200
DOI: 10.1016/j.btre.2019.e00388