Project description:Patients with leukemic cutaneous T-cell lymphoma (L-CTCL) have a poor prognosis due to development of drug-resistance and severe bacterial infections. Here, we use multimodal single-cell T-cell receptor and cellular indexing of transcriptomes and epitope sequencing (scTCR+CITE-seq) to show that most L-CTCL patients harbor multiple genetically distinct subclones that express an identical clonal antigen receptor but display distinct phenotypes and functional properties. These co-existing malignant subclones exhibit differences in tissue homing, metabolism, and cytokine expression, and respond differently to extrinsic factors like Staphylococcus (S.) aureus and cancer drugs. Indeed, while S. aureus toxins selectively enhance activation and proliferation of certain subclones, these responsive subclones are also the most intrinsically sensitive to cancer drugs when the stimuli are removed
Project description:Identifying the molecular targets for the beneficial or detrimental effects of small-molecule drugs is an important and currently unmet challenge. We have developed a method, drug affinity responsive target stability (DARTS), which takes advantage of a reduction in the protease susceptibility of the target protein upon drug binding. DARTS is universally applicable because it requires no modification of the drug and is independent of the mechanism of drug action. We demonstrate use of DARTS to identify known small-molecule-protein interactions and to reveal the eukaryotic translation initiation machinery as a molecular target for the longevity-enhancing plant natural product resveratrol. We envisage that DARTS will also be useful in global mapping of protein-metabolite interaction networks and in label-free screening of unlimited varieties of compounds for development as molecular imaging agents.
Project description:Multi-drug resistant Staphylococcus aureus (S. aureus) infections continously threaten public health. The rapid escalation in morbidity and mortality rates associated with methicillin-resistant S. aureus (MRSA) infections necessitates the urgent development of novel antimicrobial agents. Our study reveals that the FDA-approved drug cinacalcet (CNA) effectively functions as an antibacterial and anti-biofilm agent against S. aureus without detectable resistance. It evidently improved survival rate of mice infected with clinical multi-resistant S. aureus in a pneumonia model. Subsequent proteomic and biochemical experiments suggest that the primary antibacterial mechanism involves membrane structure disruption, ATP content reduction, and reactive oxygen species (ROS) production. Concurrently, LiP-SMap combined with biochemical validation indicates that CNA inhibits biofilm formation by targeting IcaR, a negative regulator of icaADBC, thereby enhancing its binding capacity to the ica operator DNA and subsequently suppressing extracellular polysaccharide formation. Importantly, compared to vancomycin, CNA demonstrates stronger biofilm bacterial clearance in a mouse thigh infection model. Collectively, our findings propose that CNA can be repurposed as a potential therapeutic agent for treating multidrug-resistant S. aureus infections and their associated biofilms.
Project description:Compilation fo whole genome gene expression changes in Staphylococcus aureus USA300 LAC cultures grown in the presence of vehicle or the anti-gout drug benzbromarone. The drug was intially screened as effective against the agr quorum sensing system in Staphylococcus aureus AH1677. A microarray study using total RNA harvested from three cultures of Staphylococcus aureus USA300 LAC plus vehicle control and three cultures of Staphylococcus aureus USA300 LAC plus 12 uM benzbromarone.
Project description:Compilation fo whole genome gene expression changes in Staphylococcus aureus USA300 LAC cultures grown in the presence of vehicle or the anti-gout drug benzbromarone. The drug was intially screened as effective against the agr quorum sensing system in Staphylococcus aureus AH1677.
Project description:Staphylococcus aureus is an opportunistic pathogen capable of causing various infections ranging from superficial skin infections to life-threatening severe diseases, including pneumonia and sepsis. This bacterium is attached to biotic and abiotic surfaces and forms biofilms that are resistant to conventional antimicrobial agents and clearance by host defenses. Infections associated with biofilms may result in longer hospitalizations, a need for surgery, and may even result in death. Agents that inhibit the formation of biofilms and virulence without affecting bacterial growth to avoid the development of drug resistance could be useful for therapeutic purposes. In this regard, we identified and isolated a small cyclic peptide, gurmarin, from a plant source that inhibited the formation of S. aureus biofilm without affecting the growth rate of the bacterium. We determined the gene expression of S. aureus biofilm treated with gurmarin and compared it to the untreated control biofilms. Differentially expressed genes were identified and their roles in the inhibition of S. aureus biofilms by gurmarin were analyzed.
Project description:To study the effect of Radix Paeoniae Rubra decoction on tolerance of Staphylococcus aureus.The effect of Radix Paeoniae Rubra on the resistance of Staphylococcus aureus to oxacillin sodium was studied by millipore dilution method in this experiment.At the same time ,conducted on transcriptome analysis of Staphylococcus aureus related genes in Radix Paeoniae Rubra.And to detect the expression level of related genes of Staphylococcus aureus under the action of Radix Paeoniae Rubra by PCR technology.The tolerance of Staphylococcus aureus was decreased obviously when the concentration of Radix Paeoniae Rubra decoction was above 1mg/ml.The effect of Radix Paeoniae Rubra decoction on the expression of tolerance genes femB,pvL and gluM when the concentration of Radix Paeoniae Rubra decoction was above 4mg/ml.When rhe concentration of Radix Paeoniae Rubra is more than 1mg/ml,it can effectively reduce the resistance of Staphylococcus aureus to oxacillin sodium.The reason may be due to the effect of Radix Paeoniae Rubra on the resistance gene of Staphylococcus aureus.
Project description:Staphylococcus aureus is a major human pathogen and resistant to numerous clinically used antibiotics. The first antibiotic developed for S. aureus infections was the nonribosomal petide secondary metabolite penicillin. We discovered cryptic nonribosomal peptide secondary metabolites, the aureusimines, made by S. aureus itself that are not antibiotics, but function as small molecule regulators of virulence factor expression. Using established rules and codes for nonribosomal peptide assembly we predicted these nonribosomal peptides, and used these predictions to identify them from S. aureus culture broths. Functional studies using global microarray and mouse bacteremia models established that the aureusimines control virulence factor expression and are necessary for productive infections. This is the first report of the aureusimines and has important implications for the treatment of drug resistant S. aureus. Targeting aureusimine synthesis may provide novel anti-infectives. Commerically available S. aureus GeneChips (Affymetrix) were used to compare biological replicates of early and late exponential phase wild type (Newman) and aureusimine defective (ausA) organisms.
Project description:Artemetin is a valuable 5-hydroxy-3,6,7,3',4'-pentamethoxyflavone found in many different medicinal plants with a very good oral bioavailability and drug-likeness values endowed with numerous bioactivities such as anti-inflammatory and anti-cancer ones. Here, a multi-disciplinary strategy has been developed and applied for identifying Artemetin target(s) to fully address its mechanism of action, based on drug affinity response target stability and targeted limited proteolysis. Both approaches point to the identification of Filamins A and B as major Artemetin targets in HeLa cell lysates, giving also detailed insights into the ligand/proteins interaction sites. Interestingly, also the 8-prenyl-Artemetin, which is a more permeable semisynthetic analog, directly interacts with Filamin A and B. Both compounds alter filamins conformation in living HeLa cells with an effect on cytoskeleton disassembly and on the disorganization of the F-actin filaments, mediated by the dissociation of filamins. Both the natural compound and its derivative are able to block cell migration, expectantly acting on tumor metastasis’s occurrence and development.
Project description:Staphylococcus aureus is a major human pathogen and resistant to numerous clinically used antibiotics. The first antibiotic developed for S. aureus infections was the nonribosomal petide secondary metabolite penicillin. We discovered cryptic nonribosomal peptide secondary metabolites, the aureusimines, made by S. aureus itself that are not antibiotics, but function as small molecule regulators of virulence factor expression. Using established rules and codes for nonribosomal peptide assembly we predicted these nonribosomal peptides, and used these predictions to identify them from S. aureus culture broths. Functional studies using global microarray and mouse bacteremia models established that the aureusimines control virulence factor expression and are necessary for productive infections. This is the first report of the aureusimines and has important implications for the treatment of drug resistant S. aureus. Targeting aureusimine synthesis may provide novel anti-infectives.