Ontology highlight
ABSTRACT:
PROVIDER: PRJNA728203 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Genome-wide screens have discovered a large set of essential genes in the human pathogen Streptococcus pneumoniae. However, the function of many essential genes is still unknown, hampering vaccine and drug development programs. Based on results from transposon-sequencing (Tn-Seq), we refined the list of essential genes in S. pneumoniae serotype 2 strain D39. Next, we created a knockdown library targeting all 391 potentially essential genes using CRISPR interference (CRISPRi). Using high-content microscopy screening, we searched for essential genes of unknown function with clear phenotypes in cell morphology upon CRISPRi-based depletion. We identified SPD1416 and SPD1417 (named to MurT and GatD, respectively) as essential peptidoglycan synthesis proteins and we show that SPD1198 and SPD1197 (named to TarP and TarQ, respectively) are responsible for the polymerization of teichoic acid (TA) precursors. This knowledge enabled us to reconstruct the unique pneumococcal TA biosynthetic pathway. Our CRISPRi library provides a valuable tool for characterization of pneumococcal genes and pathways and revealed several promising antibiotic targets. This RNA-Seq dataset is aimed to show that induction of the CRISPRi system very selectively represses its target gene, firefly luciferase, without other observable transcriptional effects.
2017-03-03 | GSE89763 | GEO
Project description:Genome-scale CRISPR interference (CRISPRi) is widely utilized to study cellular processes in a variety of organisms. To date, a genome-wide CRISPRi library, optimized for targeting the Saccharomyces cerevisiae genome, has not been presented. Here, we have generated a comprehensive, inducible CRISPRi library, based on spacer design rules optimized for yeast. We have validated this library for genome-wide interrogation of gene function across a variety of applications, including accurate discovery of haploinsufficient genes and identification of enzymatic and regulatory genes involved in adenine and arginine biosynthesis. The comprehensive nature of the library also revealed refined spacer design parameters for transcriptional repression, including location, nucleosome occupancy and nucleotide features. CRISPRi screens using this library can identify genes and pathways with high precision and low false discovery rate across a variety of experimental conditions, enabling rapid and reliable genome-wide assessment of genetic function and interactions in S. cerevisiae.
2020-11-27 | GSE159409 | GEO
Project description:Primary objectives: The study investigates whether a Escherichia coli Nissle-suspenison has a (preventive) antidiarrheal effect in patients with tumors who are treated with chemotherapeutic schemes which are associated with increased occurances of diarrhea. Diarrhea caused by treatment are thought to be reduced in intensity and/or frequency by the treatment with Escherichia coli Nissle-Suspension.
Primary endpoints: Common toxicity criteria (CTC) for diarrhea
| 2534265 | ecrin-mdr-crc
Project description:CRISPRi knockdown of essential genes in Pseudomonas aeruginosa
| PRJNA668371 | ENA
Project description:Comprehensive analysis of PNA-based antisense antibiotics targeting various essential genes in uropathogenic Escherichia coli
| PRJNA790957 | ENA
Project description:The purpose of this study is to determine whether the presence of pathogenic Escherichia coli in colon is associated with psychiatric disorders.
| 2230352 | ecrin-mdr-crc
Project description:CRISPRi screen in E. coli MG1655 with the EcoWG1 library
| PRJEB35422 | ENA
Project description:Purpose: In this study, Escherichia coli DH5alpha whole transcriptome sequencing was performed in order to compare the different gene expression profiles between control and exposed to Wi-Fi radiofrequency radiations. Methods:Escherichia coli DH5alpha were exposed to Wi-Fi radiations. Total RNA samples( control and exposed ) were extracted by bacteria protect-Rneasy kit,treated with DNAase and subjected to sequnecing using an Illumina-NovaSeq 6000 platform. Library preparation and sequencing were performed by Macrogen (south korea).Trimmed reads are mapped to reference genome with Bowtie. HTseq was used for expression profiling. Expression profile was calculated for each sample and gene as read count.
2019-10-21 | GSE126584 | GEO
Project description:Enzymes maintain metabolism and their concentration affects cellular fitness. High enzyme-levels are costly, but low enzyme-levels can limit metabolic flux. Here, we used CRISPR interference (CRISPRi) to study the consequences of decreasing metabolic enzymes in E. coli below wild-type levels. A time-resolved competition assay with a metabolism-wide CRISPRi library showed that fitness defects appeared late after induction of knockdowns. This suggested that metabolism is robust against decreases of enzymes. The metabolome and proteome of 30 CRISPRi strains revealed the mechanisms that enabled this robustness. First, substrates and allosteric effectors buffered knockdowns by increasing the activity of target-enzymes. Later, metabolite-transcription interactions compensated knockdowns by upregulating the target-pathway or bypass-pathways. For example, we found a new regulation strategy in which 6-phosphogluconate is responsible for bypassing bottlenecks in the pentose-p pathway via the Entner-Doudoroff-pathway. Thus, regulatory metabolites buffer decreases of enzyme-levels, which can occur in nature due to expression noise, mutations or environmental conditions.
2020-10-20 | PXD022070 | Pride
Project description:Over the last decade, gene-silencing mediated by dCas9 binding to transcribed regions or their promoters, a strategy referred to as CRISPRi, has emerged as a powerful tool in bacterial genetics. While this strategy has already been broadly adopted, several studies have reported experimental setups in which dCas9 expression was toxic. In particular, guide RNAs that share specific PAM-proximal sequence motifs were shown to be toxic to E. coli. Here we demonstrate that this toxicity is caused by off-target binding of dCas9 to the promoter of essential genes. Silencing of off-target genes can occur with as little as 4nt of identity between the PAM-proximal sequence and the off-target position. This phenomenon only occurs in some promoter sequences but does not appear to be constrained to any specific PAM-proximal sequence. Accordingly, screens performed in various strains of E. coli and related species shows that the nature of toxic guide RNAs changes together with the evolution of the sequence of off-target positions. These results highlight the importance of relying on several guide RNAs targeting the same gene when performing CRISPRi experiments in bacteria in order to avoid any possible confounding results due to off-target binding.
2022-11-04 | GSE217004 | GEO