Project description:Cystic Fibrosis (CF) is the most common life limiting genetic disorder, characterized by chronic respiratory failure secondary to inflammation and chronic bacterial lung infection. Pseudomonas aeruginosa lung infection is associated with more severe lung disease and rapid progression of respiratory failure when compared to Staphylococcus aureus infection. We hypothesized that a specific signature of epigenetic factors targeting specific gene transcripts contributes to the increased morbidity seen in CF patients with chronic Pseudomonas infection. We collected exhaled breath condensate (EBC) from 27 subjects and evaluated miRNA signatures in these samples using commercial PCR array. We identified predicted mRNA targets and associated signaling pathways using Ingenuity Pathway Analysis. We found 11 differentially expressed miRNAs in EBC of patients infected with Pseudomonas aeruginosa compared to EBC from CF patients who were not chronically infected with Pseudomonas aeruginosa.
Project description:Staphylococcus aureus and Pseudomonas aeruginosa are bacterial pathogens that have been shown to co-exist in biofilms related to numerous infections. Although the interaction between these two species is competitive, both partially benefit from the coexistence. In this study, we exhaustively characterized the interaction between Staphylococcus aureus and Pseudomonas aeruginosa by utilizing a proteomics approach, individually targeting the surface-associated proteins (surfaceome), and proteins secreted or otherwise liberated to the extracellular space (exoproteome). To that end, the conditions to co-culture S. aureus and P. aeruginosa in vitro were optimized and a high-resolution proteomics approach was applied to compare surface-associated and extracellular protein profiles between mono- and co-cultured biofilms.
Project description:We sequenced mRNA from three independent biological replicates of Staphylococcus epidermidis biofilms with different proportion of dormant cells. Whole trancriptome analysis of Staphylococcus epidermidis biofilms with prevented and induced dormancy.
Project description:Cerebrospinal fluid (CSF) shunt infection is a common and devastating complication of the treatment of hydrocephalus. Timely and accurate diagnosis is essential as these infections can lead to long term neurologic consequences like seizures, decreased IQ and impaired school performance. Currently the diagnosis of shunt infection relies on bacterial culture, however, culture is not always accurate especially as these infections are frequently caused by bacteria capable of forming biofilms like Staphylococcus epidermidis, Cutibacterium acnes, and Pseudomonas aeruginosa and may have very few planktonic bacteria in the CSF to be picked up on culture. Therefore, there is a critical need to identify a new rapid, and accurate method for diagnosis of CSF shunt infection with broad bacterial species coverage to improve the long-term outcomes of children suffering from these infections.
Project description:We examined the differential gene expression of Staphylococcus epidermidis and Staphylococcus epidermidis in dual species biofilms. Therefore, we performed RNA-Seq on single and dual species biofilms and we compared the gene expression levels in dual species biofilms to those in single species biofilms.
Project description:Engineered live bacteria could provide a new modality for treating lung infections , a major cause of mortality worldwide. Here, we engineered a genome-reduced human lung bacterium, Mycoplasma pneumoniae, to treat ventilator-associated pneumonia (VAP), a disease with high hospital mortality when associated with Pseudomonas aeruginosa biofilms. After validating the biosafety of an attenuated M. pneumoniae chassis in mice, we introduced four transgenes in the chromosome by transposition, to implement bactericidal and biofilm degradation activities. We show that this engineered strain has high efficacy against an acute P. aeruginosa lung infection in a mouse model. In addition, we demonstrate that the engineered strain can dissolve biofilms formed in endotracheal tubes of VAP patients and can be combined with antibiotics targeting the peptidoglycan layer to increase efficacy against gram-positive and gram-negative bacteria. We expect that our
Project description:The clinical importance of microbiomes to the chronicity of wounds is widely appreciated, yet little is understood about patient-specific processes shaping wound microbiome composition. Here, a two-cohort microbiome-genome wide association study is presented through which patient genomic loci associated with chronic wound microbiome diversity were identified. Further investigation revealed that alternative TLN2 and ZNF521 genotypes explained significant inter-patient variation in relative abundance of two key pathogens, Pseudomonas aeruginosa and Staphylococcus epidermidis. Wound diversity was lowest in Pseudomonas aeruginosa infected wounds, and decreasing wound diversity had a significant negative linear relationship with healing rate. In addition to microbiome characteristics, age, diabetic status, and genetic ancestry all significantly influenced healing. Using structural equation modeling to identify common variance among SNPs, six loci were sufficient to explain 53% of variation in wound microbiome diversity, which was a 10% increase over traditional multiple regression. Focusing on TLN2, genotype at rs8031916 explained expression differences of alternative transcripts that differ in inclusion of important focal adhesion binding domains. Such differences are hypothesized to relate to wound microbiomes and healing through effects on bacterial exploitation of focal adhesions and/or cellular migration. Related, other associated loci were functionally enriched, often with roles in cytoskeletal dynamics. This study, being the first to identify patient genetic determinants for wound microbiomes and healing, implicates genetic variation determining cellular adhesion phenotypes as important drivers of infection type. The identification of predictive biomarkers for chronic wound microbiomes may serve as risk factors and guide treatment by informing patient-specific tendencies of infection.
Project description:Pseudomonas aeruginosa and Staphylococcus aureus are often co-isolated in persistent infections. The goal of this study was to determine how secreted products that were identified in S. aureus supernatant affect gene expression in P. aeruginosa. Therefore, media control, the indicated products in media, or S. aureus supernatant was added to P. aeruginosa cultures at 25% total volume and gene expression was measured at 20 min and 2 h using RNA-seq. The individual products induced distinct pathways in P. aeruginosa. The products in combination recapitulated much of the differential gene expression seen in P. aeruginosa in response to S. aureus supernatant.