ABSTRACT: On our microbial screening effort. We identified promising activity. Chasing the activity we annotated the molecules along with some computational docking studies.
Project description:There is a growing need for novel antiviral therapies that are broad-spectrum, effective, and not subject to resistance due to viral mutations. Using high-throughput screening methods, including computational docking studies and an ISG54-luciferase reporter assay, we identified a class of isoflavone compounds that act as specific agonists of innate immune signaling pathways and cause activation of the IRF-3 transcription factor. The objective of the microarray study was to examine the biological pathways associated with global gene expression changes following agonist treatment.
Project description:The most commonly used genome annotation processes are to a great extent based on computational methods. However, those can only predict genes that have been described earlier or that have sequence signatures indicative of a gene function. We reported a synonymous proteogenomic approach for experimentally improving microbial genome annotation based on label-free quantitative MS/MS. The approach was exemplified by analysis of cell extracts from in vitro cultured enterotoxigenic Escherichia coli (ETEC) strain TW10598, as part of an effort to create a new reference ETEC genome sequence. The proteomic analysis yielded identification of 2,060 proteins, out of which 274 proteins were originally described as hypothetical. For 84% of the identified proteins we have provided description of their relative quantitative levels, among others, for 20 abundantly expressed ETEC virulence factors. Proteogenomic mapping supported the existence of four protein-coding genes that had not been annotated, and led to correction of translation start positions of another nine.
Project description:The identification and validation of a small molecule's targets is a major bottleneck in the discovery process for tuberculosis antibiotics. Activity-based protein profiling (ABPP) is an efficient tool for determining a small molecul's targets within complex proteomes. However, how target inhibition relates to biological activity is often left unexplored. Here we studied the effects of 1,2,3-triazole ureas on Mycobacterium tuberculosis . After screening ~200 compounds, we focused on two inhibitors active against both exponentially replicating and hypoxia-induced drug-tolerant Mtb that form part of a four-compound structure-activity series. The compound with negligible activity revealed potential false positive targets not addressed in other ABPP studies. Biochemistry, computational docking, and morphological analysis confirmed that active compounds preferentially inhibit serine hydrolases with cell wall and lipid metabolism functions and that disruption of the cell wall underlies biological activity. Our findings showed that ABPP identifies the targets most likely relevant to a compound's antibacterial activity.
Project description:There is a growing need for novel antiviral therapies that are broad-spectrum, effective, and not subject to resistance due to viral mutations. Using high-throughput screening methods, including computational docking studies and an ISG54-luciferase reporter assay, we identified a class of isoflavone compounds that act as specific agonists of innate immune signaling pathways and cause activation of the IRF-3 transcription factor. The objective of the microarray study was to examine the biological pathways associated with global gene expression changes following agonist treatment. Total RNA isolation and mRNA amplification were performed on equal masses of total RNA from MRC5 cells treated with either DMSO (negative control; n=3), or 10μM of the isoflavone agonist KIN 101 (n=3) at 20 hours post treatment. As a positive control for response to an RNA virus, total RNA isolation and mRNA amplification was performed on equal masses of total RNA from MRC5 cells infected with Sendai virus (n=3) at 20 hours post infection.
Project description:The aim of this work was to unveil the molecular mechanisms by which Streptomyces respond to a ROS intracellular imbalance and the effect of such response on the biosynthesis of secondary metabolites. The study was focused on the industrial actinomycete S. natalensis ATCC 27448 producer of the polyene pimaricin - an antifungal agent widely used in the food industry and promising for antiviral activity and stimulation of immune response.
Project description:<p>Diffuse Intrinsic Pontine Glioma (DIPG) is a universally fatal childhood cancer. Here, we performed a chemical screen in patient-derived DIPG cell cultures along with RNAseq expression analysis and integrated computational modeling to identify potentially effective therapeutic strategies. Panobinostat, among the more promising agents identified, demonstrated efficacy in pontine orthotopic xenograft models of both H3K27M and histone WT DIPG. These data suggest the potential utility of specific drug combinations and provides evidence of in vivo treatment efficacy of the multi-histone deacetylase inhibitor panobinostat. We are depositing to dbGaP deep sequencing whole exome data for 22 patient tumor samples and 13 matched normals, along with RNAseq data for 12 patient tumor samples and 6 normal pediatric brain tissue samples. In addition, we are depositing 22 RNAseq samples from DIPG cell lines before and after panobinostat treatment.</p>
Project description:Understanding and quantifying the effects of environmental factors influencing the variation of abundance and diversity of microbial communities was a key theme of ecology. For microbial communities, there were two factors proposed in explaining the variation in current theory, which were contemporary environmental heterogeneity and historical events. Here, we report a study to profile soil microbial structure, which infers functional roles of microbial communities, along the latitudinal gradient from the north to the south in China mainland, aiming to explore potential microbial responses to external condition, especially for global climate changes via a strategy of space-for-time substitution. Using a microarray-based metagenomics tool named GeoChip 5.0, we showed that microbial communities were distinct for most but not all of the sites. Using substantial statistical analyses, exploring the dominant factor in influencing the soil microbial communities along the latitudinal gradient. Substantial variations were apparent in nutrient cycling genes, but they were in line with the functional roles of these genes. 300 samples were collected from 30 sites along the latitudinal gradient, with 10 replicates in every site
Project description:Screening large molecule libraries against pathogenic bacteria is often challenged by a low hit rate due to limited uptake, underrepresentation of antibiotic structural motifs and assays which do not resemble the infection conditions. To address these limitations, we here screen a library focused on alkylguanidinium compounds, a structural motif associated with antibiotic activity and enhanced uptake, under host-mimicking infection conditions against a panel of disease-associated bacteria. Several hit molecules were obtained with activities against Gram-positive as well as Gram-negative bacteria highlighting the fidelity of the general concept. Based on the best antibiotic activity, we selected one compound (L15) for in-depth mode of action studies. L15 exhibited bactericidal activity against Staphylococcus aureus USA300 Lac (JE2) with a minimum inhibitory concentration of 1.5 µM whereby a structure-activity relationship study with 18 derivatives proved the necessity of the guanidinium motif for antibiotic activity. Electron microscopy studies and depolarization assays at high L15 concentrations showed an impact on the cell membrane and integrity which was absent at the MIC concentration. Sequencing of L15-resistant strains revealed a mutation in an efflux pump but did not provide hints for direct targets. We thus performed affinity-based protein profiling with a L15 probe and identified signal peptidase IB (SpsB) as the most promising hit. Validation by activity assays, binding site identification and molecular docking demonstrated SpsB overactivation by L15, similar to a previously reported activator molecule that dysregulates protein secretion of this essential enzyme. Overall, this study highlights the need for unconventional screening strategies to identify novel antibiotics.
Project description:The discovery of effective senolytics offers a promising approach for treating many age-related diseases. In this study, we employed a phenotypic drug discovery approach, combining drug screening and drug design, to identify and develop novel senolytic agents based on the flavonoid fisetin. We successfully developed two novel flavonoid analogs, SR29384 and SR31133, which demonstrated significantly enhanced senolytic activities compared to fisetin. These analogs showed broad-spectrum efficacy in eliminating various senescent cell types, reducing tissue senescence, extending healthspan in mice, and prolonging lifespan in Drosophila. Through RNA sequencing, machine learning, and computational screening, our mechanistic studies suggest that these novel flavonoid senolytics may target PARP1, BCL2L1, and CDK2 to induce senescent cell death.