ABSTRACT: An alkaliphilic isosaccharinic acid polymicrobial floc forming community operating under intermediate level waste conditions at pH 11. Targeted loci cultured
Project description:To describe the transcriptional changes associated with polymicrobial-sepsis induced myocardial depression in wild type and iNOS deficient mice. Keywords: myocardium, contractility, differential gene expression, nitric oxide synthase, infection We compared the transcriptional profile of C57/BL6 WT mice and congenic B6 129P2-Nos2tm1Lau/J mice after 48 hrs of polymicrobial sepsis induced by caecal ligation and perforation. 48 hours after surgery, mice were anaesthetised (intraperitoneal 100 mg/kg ketamine and 10 mg/kg xylazine). The right common carotid artery was cannulated (Millar Mikro-Tip pressure transducing catheter: 1.4F sensor, 2F catheter; Houston TX). Pressure tracings from the aorta and left ventricle were recorded (SonoLAB software; Sonometrics Corp., London Ontario Canada) and analysed using Cardiosoft and Origin 6.0 (Sonometrics Corp., and Microcal Software, Northampton MA). The heart was removed, emptied of blood, and snap frozen.
Project description:When Proteus mirabilis, Enterococcus faecalis, and Escherichia coli are co-cultured in human urine, they form biofilms with increased biomass. This increase in biomass is due to a rise in the total protein content of the biofilm rather than other components, such as carbohydrates or nucleic acids. The study focused on identifying proteins that are enriched in polymicrobial biofilms (co-cultures) compared to monomicrobial biofilms. Proteins that increase in relative abundance during co-culture may serve as targets for preventing the formation of recalcitrant polymicrobial biofilms.
Project description:Many human infections are polymicrobial in origin, and interactions among community inhabitants shape colonization patterns and pathogenic potential1. However, few interspecies interactions have been functionally dissected at the molecular level or characterized on a systems level. Periodontitis, which is the sixth most prevalent infectious disease worldwide2, ensues from the action of dysbiotic polymicrobial communities3. The keystone pathogen Porphyromonas gingivalis and the accessory pathogen Streptococcus gordonii interact to form communities in vitro and exhibit increased fitness in vivo3, 4. The mechanistic basis of this polymicrobial synergy, however, has not been fully elucidated. Here we show that streptococcal 4 aminobenzoate/para-amino benzoic acid (pABA) is required for maximal accumulation of P. gingivalis in dual species communities. Metabolomic and proteomic data showed that exogenous pABA is utilized for folate biosynthesis, and leads to decreased stress and elevated expression of fimbrial interspecies adhesins. Moreover, pABA increased the colonization and survival of P. gingivalis in a murine oral infection model. However, pABA also caused a reduction in virulence in vivo and suppressed extracellular polysaccharide production by P. gingivalis. Collectively, these data reveal a multidimensional aspect to P. gingivalis-S. gordonii interactions and establish pABA as a critical cue produced by a partner species that enhances fitness of P. gingivalis while diminishing virulence.
Project description:We systematically assessed the transcriptomic changes of livers of MxCreFthD/D vs. Fthlox/lox mice after induction of polymicrobial sepsis using Cecal Ligation and Puncture. Data indicates a distinct set of genes differentially regulated between MxCreFthD/D and Fthlox/lox mice after sepsis induction reflecting altered iron and glucose metabolism.
Project description:Adults with cystic fibrosis (CF) have chronic antibiotic-resistant polymicrobial lung infections, the leading cause of death in CF. We developed a polymicrobial culture model containing four genera that represents a ‘pulmotype’ detected in ~34% of lung infections in people with CF (pwCF), and accounts for 27% of the variability in lung function. This community, comprised of Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus sanguinis, and Prevotella melaninogenica, is grown in synthetic CF media (SCFM2) under anoxic conditions that mimic the environment in mucus plugs in CF. We have shown that Pseudomonas in monoculture communicates with primary human bronchial epithelial cells (pHBEC) by secreting bacterial extracellular vesicles (bEVs) that diffuse through mucus and deliver virulence factors, DNA, and RNA to pHBEC. We report herein that each bacterial genus in the polymicrobial community secretes bEVs containing proteins and RNAs predicted to promote the establishment of chronic infection by enhancing virulence and biofilm formation, and upregulating the stress response and pro-inflammatory pathways in pHBEC. This response is most pronounced in CF pHBEC. Trikafta, a highly effective drug, does not ameliorate the response or return it to WT levels. Bacterial EVs also inhibited Trikafta-stimulated CFTR Cl- currents by CF pHBEC. These studies provide insight into why Trikafta does not eliminate polymicrobial lung infections and a hyperinflammatory lung environment in pwCF.
Project description:Adults with cystic fibrosis (CF) have chronic antibiotic-resistant polymicrobial lung infections, the leading cause of death in CF. We developed a polymicrobial culture model containing four genera that represents a ‘pulmotype’ detected in ~34% of lung infections in people with CF (pwCF), and accounts for 27% of the variability in lung function. This community, comprised of Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus sanguinis, and Prevotella melaninogenica, is grown in synthetic CF media (SCFM2) under anoxic conditions that mimic the environment in mucus plugs in CF. We have shown that Pseudomonas in monoculture communicates with primary human bronchial epithelial cells (pHBEC) by secreting bacterial extracellular vesicles (bEVs) that diffuse through mucus and deliver virulence factors, DNA, and RNA to pHBEC. We report herein that each bacterial genus in the polymicrobial community secretes bEVs containing proteins and RNAs predicted to promote the establishment of chronic infection by enhancing virulence and biofilm formation, and upregulating the stress response and pro-inflammatory pathways in pHBEC. This response is most pronounced in CF pHBEC. Trikafta, a highly effective drug, does not ameliorate the response or return it to WT levels. Bacterial EVs also inhibited Trikafta-stimulated CFTR Cl- currents by CF pHBEC. These studies provide insight into why Trikafta does not eliminate polymicrobial lung infections and a hyperinflammatory lung environment in pwCF.