Project description:Advancing Negative Ion Mode Proteomics. The main objective of the project is the exploration of the unconvetional negative ion mode for proteomics studies. In this work, we thoroughly studied the best chromatographic conditions for negative ion mode proteomics before testing different enzymatic digestion. The final goal is to establish the best working conditions in the negative polarity for negative ion mode. The method also refrains from any fragmentation events, which are unpredictable in negative ion mode.
Project description:Due to the rise of drug resistant forms of tuberculosis there is an urgent need for novel antibiotics to effectively combat these cases and to shorten treatment regimens. Recently, drug screens using whole cell analyses have shown to be successful. However, current high throughput screens focus mostly on stricto sensu life-death screening that give little qualitative information and often require the lengthy process of target and mode of action (MoA) identification. In doing so, promising compound scaffolds or non-optimized compounds that fail to reach inhibitory concentrations are missed. To accelerate early TB drug discovery, we performed RNA sequencing on Mycobacterium tuberculosis and Mycobacterium marinum to map the stress responses that follow upon exposure to sub-inhibitory concentrations of antibiotics with known targets: ciprofloxacin, ethambutol, isoniazid, streptomycin and rifampicin. The resulting dataset comprises the first overview of transcriptional stress responses of mycobacteria to different antibiotics. We show that antibiotics can be distinguished based on their specific transcriptional stress fingerprint i.e. DNA damage for ciprofloxacin and ribosomal stress for streptomycin. Notably, this fingerprint was more distinctive in M. marinum and we decided to use this to our advantage and continue with this model organism. A selection of diverse antibiotic stress genes was used to construct stress reporters. In total, three functional reporters were constructed for DNA damage, cell wall damage and ribosomal inhibition. Subsequently, these reporter strains were used to screen a small anti-TB compound library to predict the mode of action. In doing so we could identify the putative mode of action for three novel compounds, which confirms our approach.
Project description:Due to the rise of drug resistant forms of tuberculosis there is an urgent need for novel antibiotics to effectively combat these cases and to shorten treatment regimens. Recently, drug screens using whole cell analyses have shown to be successful. However, current high throughput screens focus mostly on stricto sensu life-death screening that give little qualitative information and often require the lengthy process of target and mode of action (MoA) identification. In doing so, promising compound scaffolds or non-optimized compounds that fail to reach inhibitory concentrations are missed. To accelerate early TB drug discovery, we performed RNA sequencing on Mycobacterium tuberculosis and Mycobacterium marinum to map the stress responses that follow upon exposure to sub-inhibitory concentrations of antibiotics with known targets: ciprofloxacin, ethambutol, isoniazid, streptomycin and rifampicin. The resulting dataset comprises the first overview of transcriptional stress responses of mycobacteria to different antibiotics. We show that antibiotics can be distinguished based on their specific transcriptional stress fingerprint i.e. DNA damage for ciprofloxacin and ribosomal stress for streptomycin. Notably, this fingerprint was more distinctive in M. marinum and we decided to use this to our advantage and continue with this model organism. A selection of diverse antibiotic stress genes was used to construct stress reporters. In total, three functional reporters were constructed for DNA damage, cell wall damage and ribosomal inhibition. Subsequently, these reporter strains were used to screen a small anti-TB compound library to predict the mode of action. In doing so we could identify the putative mode of action for three novel compounds, which confirms our approach.
Project description:To elucidate the antivirulent lactone U1 mode of action, next generation sequencing was applied to analyze the transcriptome of NCTC 8325 cells treated with either compound or DMSO as control.
Project description:To elucidate the antivirulent hydroxy amide (R*,R*)-3 mode of action, next generation sequencing was applied to analyze the transcriptome of NCTC 8325 cells treated with either compound or DMSO as control.
Project description:Samples from mice infected and then treated with vehicle, carnitine or benznidazole in the chronic stage of infection. Tissue samples extracted with 50% methanol followed by 3:1 dichloromethane:methanol. C8 chromatography with negative mode data acquisition
Project description:This data set was collected on a qexactive coupled to a Thermo vanquish. Data was collected in a DDA fashion in negative mode. The project itself revolved around compound 94NPD2, a compound that is similar to veraguamides
Project description:Maldi imaging with NEDC matrix of a rat brain tissue section. Image was acquired with 50 um resolution. Ion mobility seperation enabled. Negative ion mode.