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Frontiers in Cellular and Infection... 2020While extensive literature exists about the role of oral bacterial pathogens like and in oral squamous cell carcinoma (OSCC), the role of health-associated species has...
While extensive literature exists about the role of oral bacterial pathogens like and in oral squamous cell carcinoma (OSCC), the role of health-associated species has been largely unexplored. In this study, we assessed the effect of , and on proliferation and expression of marker genes (IL-6, TNF-α, MMP3, CD36, CCD1, and NANOG) in OSCC cell lines CAL27, SCC25, and SCC4. was included as a pathogenic control. Both bacterial lysates (3 concentrations) and live cells (3 MOIs) were tested. , and resulted in substantial, dose-dependent reduction of proliferation, which was found to be mediated by HO for the former and intracellular infection in the latter two species. However, only 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 upregulated it. IL6 and TNF expression, on the other hand, was upregulated by almost all species, particularly the Gram-negatives including . 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.
Topics: Burkholderiaceae; Carcinoma, Squamous Cell; Fusobacterium nucleatum; Humans; Hydrogen Peroxide; Micrococcaceae; Mouth Neoplasms; Neisseria; Porphyromonas gingivalis; Veillonella
PubMed: 33123499
DOI: 10.3389/fcimb.2020.575656 -
PloS One 2021The Burkholderia pseudomallei phylogenetic cluster includes B. pseudomallei, B. mallei, B. thailandensis, B. oklahomensis, B. humptydooensis and B. singularis. Regarded...
The Burkholderia pseudomallei phylogenetic cluster includes B. pseudomallei, B. mallei, B. thailandensis, B. oklahomensis, B. humptydooensis and B. singularis. Regarded as the only pathogenic members of this group, B. pseudomallei and B. mallei cause the diseases melioidosis and glanders, respectively. Additionally, variant strains of B. pseudomallei and B. thailandensis exist that include the geographically restricted B. pseudomallei that express a B. mallei-like BimA protein (BPBM), and B. thailandensis that express a B. pseudomallei-like capsular polysaccharide (BTCV). To establish a PCR-based assay for the detection of pathogenic Burkholderia species or their variants, five PCR primers were designed to amplify species-specific sequences within the bimA (Burkholderia intracellular motility A) gene. Our multiplex PCR assay could distinguish pathogenic B. pseudomallei and BPBM from the non-pathogenic B. thailandensis and the BTCV strains. A second singleplex PCR successfully discriminated the BTCV from B. thailandensis. Apart from B. humptydooensis, specificity testing against other Burkholderia spp., as well as other Gram-negative and Gram-positive bacteria produced a negative result. The detection limit of the multiplex PCR in soil samples artificially spiked with known quantities of B. pseudomallei and B. thailandensis were 5 and 6 CFU/g soil, respectively. Furthermore, comparison between standard bacterial culture and the multiplex PCR to detect B. pseudomallei from 34 soil samples, collected from an endemic area of melioidosis, showed high sensitivity and specificity. This robust, sensitive, and specific PCR assay will be a useful tool for epidemiological study of B. pseudomallei and closely related members with pathogenic potential in soil.
Topics: Burkholderia; DNA Barcoding, Taxonomic; Microbiota; Polymerase Chain Reaction; Soil Microbiology
PubMed: 33411797
DOI: 10.1371/journal.pone.0245175 -
Current Issues in Molecular Biology 2014Methods for the rapid detection and differentiation of the Burkholderia pseudomallei complex comprising B. pseudomallei, B. mallei, and B. thailandensis, have been the... (Review)
Review
Methods for the rapid detection and differentiation of the Burkholderia pseudomallei complex comprising B. pseudomallei, B. mallei, and B. thailandensis, have been the topic of recent research due to the high degree of phenotypic and genotypic similarities of these species. B. pseudomallei and B. mallei are recognized by the CDC as tier 1 select agents. The high mortality rates of glanders and melioidosis, their potential use as bioweapons, and their low infectious dose, necessitate the need for rapid and accurate detection methods. Although B. thailandensis is generally avirulent in mammals, this species displays very similar phenotypic characteristics to that of B. pseudomallei. Optimal identification of these species remains problematic, due to the difficulty in developing a sensitive, selective, and accurate assay. The development of PCR technologies has revolutionized diagnostic testing and these detection methods have become popular due to their speed, sensitivity, and accuracy. The purpose of this review is to provide a comprehensive overview and evaluation of the advancements in PCR-based detection and differentiation methodologies for the B. pseudomallei complex, and examine their potential uses in diagnostic and environmental testing.
Topics: Animals; Bacterial Typing Techniques; Biological Warfare Agents; Burkholderia; Burkholderia mallei; Burkholderia pseudomallei; Glanders; Horses; Humans; Melioidosis; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; RNA, Ribosomal, 16S; Sensitivity and Specificity
PubMed: 23969318
DOI: No ID Found -
Antimicrobial Agents and Chemotherapy Feb 2021The Gram-negative bacterial genus includes several hard-to-treat human pathogens: two biothreat species, (causing glanders) and (causing melioidosis), and the...
The Gram-negative bacterial genus includes several hard-to-treat human pathogens: two biothreat species, (causing glanders) and (causing melioidosis), and the complex (BCC) and , which cause chronic lung infections in persons with cystic fibrosis. All spp. possess an Ambler class A Pen β-lactamase, which confers resistance to β-lactams. The β-lactam-β-lactamase inhibitor combination sulbactam-durlobactam (SUL-DUR) is in clinical development for the treatment of infections. In this study, we evaluated SUL-DUR for and activity against clinical isolates. We measured MICs of SUL-DUR against BCC and ( = 150), ( = 30), and ( = 28), studied the kinetics of inhibition of the PenA1 β-lactamase from and the PenI β-lactamase from by durlobactam, tested for induction by SUL-DUR, and evaluated efficacy in a mouse model of melioidosis. SUL-DUR inhibited growth of 87.3% of the BCC and strains and 100% of the and strains at 4/4 μg/ml. Durlobactam potently inhibited PenA1 and PenI with second-order rate constant for inactivation () values of 3.9 × 10 M s and 2.6 × 10 M s and apparent () of 15 nM and 241 nM, respectively, by forming highly stable covalent complexes. Neither sulbactam, durlobactam, nor SUL-DUR increased production of PenA1. SUL-DUR demonstrated activity in a murine melioidosis model. Taken together, these data suggest that SUL-DUR may be useful as a treatment for infections.
Topics: Animals; Anti-Bacterial Agents; Burkholderia; Burkholderia mallei; Burkholderia pseudomallei; Glanders; Horses; Melioidosis; Mice; Sulbactam
PubMed: 33318017
DOI: 10.1128/AAC.01930-20 -
Virulence Aug 2017
Topics: Burkholderia Infections; Burkholderia cenocepacia; Burkholderia cepacia complex; Cystic Fibrosis; Humans; Lung; Virulence
PubMed: 27786605
DOI: 10.1080/21505594.2016.1253660 -
Acta Crystallographica. Section F,... Jan 2022Paraburkholderia xenovorans degrades organic wastes, including polychlorinated biphenyls. The atomic structure of a putative dehydrogenase/reductase (SDR) from P....
Paraburkholderia xenovorans degrades organic wastes, including polychlorinated biphenyls. The atomic structure of a putative dehydrogenase/reductase (SDR) from P. xenovorans (PxSDR) was determined in space group P2 at a resolution of 1.45 Å. PxSDR shares less than 37% sequence identity with any known structure and assembles as a prototypical SDR tetramer. As expected, there is some conformational flexibility and difference in the substrate-binding cavity, which explains the substrate specificity. Uniquely, the cofactor-binding cavity of PxSDR is not well conserved and differs from those of other SDRs. PxSDR has an additional seven amino acids that form an additional unique loop within the cofactor-binding cavity. Further studies are required to determine how these differences affect the enzymatic functions of the SDR.
Topics: Burkholderiaceae; Crystallography, X-Ray; Oxidoreductases; Short Chain Dehydrogenase-Reductases; Substrate Specificity
PubMed: 34981772
DOI: 10.1107/S2053230X21012632 -
Cells Apr 2021Homocitrate is an essential component of the iron-molybdenum cofactor of nitrogenase, the bacterial enzyme that catalyzes the reduction of dinitrogen (N) to ammonia. In...
Homocitrate is an essential component of the iron-molybdenum cofactor of nitrogenase, the bacterial enzyme that catalyzes the reduction of dinitrogen (N) to ammonia. In nitrogen-fixing and nodulating alpha-rhizobia, homocitrate is usually provided to bacteroids in root nodules by their plant host. In contrast, non-nodulating free-living diazotrophs encode the homocitrate synthase (NifV) and reduce N in nitrogen-limiting free-living conditions. STM815 is a beta-rhizobial strain, which can enter symbiosis with a broad range of legumes, including papilionoids and mimosoids. In contrast to most alpha-rhizobia, which lack , harbors a copy of on its symbiotic plasmid. We show here that is essential for nitrogenase activity both in root nodules of papilionoid plants and in free-living growth conditions. Notably, was dispensable in nodules of despite the fact that the gene was highly expressed during symbiosis with all tested papilionoid and mimosoid plants. A metabolome analysis of papilionoid and mimosoid root nodules infected with the wild-type strain revealed that among the approximately 400 measured metabolites, homocitrate and other metabolites involved in lysine biosynthesis and degradation have accumulated in all plant nodules compared to uninfected roots, suggesting an important role of these metabolites during symbiosis.
Topics: Bacterial Proteins; Burkholderiaceae; Fabaceae; Genome, Bacterial; Green Fluorescent Proteins; Host-Pathogen Interactions; Likelihood Functions; Metabolome; Nitrogenase; Oxo-Acid-Lyases; Phylogeny; Root Nodules, Plant; Symbiosis
PubMed: 33924023
DOI: 10.3390/cells10040952 -
Journal of Bacteriology Jan 2014Burkholderia cenocepacia and Burkholderia multivorans are opportunistic drug-resistant pathogens that account for the majority of Burkholderia cepacia complex infections... (Comparative Study)
Comparative Study
Burkholderia cenocepacia and Burkholderia multivorans are opportunistic drug-resistant pathogens that account for the majority of Burkholderia cepacia complex infections in cystic fibrosis patients and also infect other immunocompromised individuals. While they share similar genetic compositions, B. cenocepacia and B. multivorans exhibit important differences in pathogenesis. We have developed reconciled genome-scale metabolic network reconstructions of B. cenocepacia J2315 and B. multivorans ATCC 17616 in parallel (designated iPY1537 and iJB1411, respectively) to compare metabolic abilities and contextualize genetic differences between species. The reconstructions capture the metabolic functions of the two species and give insight into similarities and differences in their virulence and growth capabilities. The two reconstructions have 1,437 reactions in common, and iPY1537 and iJB1411 have 67 and 36 metabolic reactions unique to each, respectively. After curating the extensive reservoir of metabolic genes in Burkholderia, we identified 6 genes essential to growth that are unique to iPY1513 and 13 genes uniquely essential to iJB1411. The reconstructions were refined and validated by comparing in silico growth predictions to in vitro growth capabilities of B. cenocepacia J2315, B. cenocepacia K56-2, and B. multivorans ATCC 17616 on 104 carbon sources. Overall, we identified functional pathways that indicate B. cenocepacia can produce a wider array of virulence factors compared to B. multivorans, which supports the clinical observation that B. cenocepacia is more virulent than B. multivorans. The reconciled reconstructions provide a framework for generating and testing hypotheses on the metabolic and virulence capabilities of these two related emerging pathogens.
Topics: Burkholderia Infections; Burkholderia cepacia complex; Computer Simulation; Cystic Fibrosis; Humans; Metabolic Networks and Pathways; Metabolome; Systems Biology; Virulence
PubMed: 24163337
DOI: 10.1128/JB.00997-13 -
PloS One 2021Burkholderia pseudomallei (B. pseudomallei) is an intracellular pathogen that causes melioidosis, a life-threatening infection in humans. The bacterium is able to form...
Burkholderia pseudomallei (B. pseudomallei) is an intracellular pathogen that causes melioidosis, a life-threatening infection in humans. The bacterium is able to form small colony variants (SCVs) as part of the adaptive features in response to environmental stress. In this study, we characterize the genomic characteristics, antimicrobial resistance (AMR), and metabolic phenotypes of B. pseudomallei SCV and wild type (WT) strains. Whole-genome sequence analysis was performed to characterize the genomic features of two SCVs (CS and OS) and their respective parental WT strains (CB and OB). Phylogenetic relationship between the four draft genomes in this study and 19 publicly available genomes from various countries was determined. The four draft genomes showed a close phylogenetic relationship with other genomes from Southeast Asia. Broth microdilution and phenotype microarray were conducted to determine the AMR profiles and metabolic features (carbon utilization, osmolytes sensitivity, and pH conditions) of all strains. The SCV strains exhibited identical AMR phenotype with their parental WT strains. A limited number of AMR-conferring genes were identified in the B. pseudomallei genomes. The SCVs and their respective parental WT strains generally shared similar carbon-utilization profiles, except for D,L-carnitine (CS), g-hydroxybutyric acid (OS), and succinamic acid (OS) which were utilized by the SCVs only. No difference was observed in the osmolytes sensitivity of all strains. In comparison, WT strains were more resistant to alkaline condition, while SCVs showed variable growth responses at higher acidity. Overall, the genomes of the colony morphology variants of B. pseudomallei were largely identical, and the phenotypic variations observed among the different morphotypes were strain-specific.
Topics: Adaptation, Biological; Burkholderia pseudomallei; Drug Resistance, Microbial; Genomics; Genotype; Phenotype; Phylogeny; Exome Sequencing
PubMed: 34910764
DOI: 10.1371/journal.pone.0261382 -
Chembiochem : a European Journal of... Oct 2021Soft rot disease of edible mushrooms leads to rapid degeneration of fungal tissue and thus severely affects farming productivity worldwide. The bacterial mushroom...
Soft rot disease of edible mushrooms leads to rapid degeneration of fungal tissue and thus severely affects farming productivity worldwide. The bacterial mushroom pathogen Burkholderia gladioli pv. agaricicola has been identified as the cause. Yet, little is known about the molecular basis of the infection, the spatial distribution and the biological role of antifungal agents and toxins involved in this infectious disease. We combine genome mining, metabolic profiling, MALDI-Imaging and UV Raman spectroscopy, to detect, identify and visualize a complex of chemical mediators and toxins produced by the pathogen during the infection process, including toxoflavin, caryoynencin, and sinapigladioside. Furthermore, targeted gene knockouts and in vitro assays link antifungal agents to prevalent symptoms of soft rot, mushroom browning, and impaired mycelium growth. Comparisons of related pathogenic, mutualistic and environmental Burkholderia spp. indicate that the arsenal of antifungal agents may have paved the way for ancestral bacteria to colonize niches where frequent, antagonistic interactions with fungi occur. Our findings not only demonstrate the power of label-free, in vivo detection of polyyne virulence factors by Raman imaging, but may also inspire new approaches to disease control.
Topics: Agaricales; Antifungal Agents; Bacterial Toxins; Burkholderia gladioli; Microbial Sensitivity Tests; Molecular Imaging; Plant Diseases
PubMed: 34232540
DOI: 10.1002/cbic.202100330