Project description:The purpose of this study is to determine whether the presence of pathogenic Escherichia coli in colon is associated with psychiatric disorders.
Project description:Despite the characterization of many aetiologic genetic changes. The specific causative factors in the development of sporadic colorectal cancer remain unclear. This study was performed to detect the possible role of Enteropathogenic Escherichia coli (EPEC) in developing colorectal carcinoma.
Project description:Here, we investigated the impact of Stx2 phage carriage on Escherichia coli (E. coli) K-12 MG1655 host gene expression. Using quantitative RNA-seq analysis, we compared the transcriptome of naïve MG1655 and the lysogens carrying the Stx2 phage of the 2011 E. coli O104:H4 outbreak strain or of the E. coli O157:H7 strain PA8, which share high degree of sequence similarity.
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.
Project description:Escherichia coli (E. coli) amine oxidase (ECAO) encoded by tynA gene has been one of the model enzymes to study the mechanism of oxidative deamination of amines to the corresponding aldehydes by amine oxidases. The biological roles of ECAO have been less addressed. Therefore we have constructed a gene deletion Escherichia coli K-12 strain, E. coli tynA-, and used the microarray technique to address its function by comparing the total RNA gene expression to the one of the wt. Our results suggest that tynA is a reserve gene for stringent environmental conditions and its gene product ECAO a growth advantage compared to other bacteria due to H2O2 production.
Project description:The model prokaryote Escherichia coli can exist as a either a commensal or a pathogen in the gut of diverse mammalian hosts. These associations, coupled with its ease of cultivation and genetic variability, have made E. coli a popular indicator organism for tracking the origin of fecal water contamination. Source tracking accuracy is predicated on the assumption that E. coli isolates recovered from contaminated water present a genetic signature characteristic of the host from which they originated. In this study, we compared the accuracy with which E. coli isolated from humans, bear, cattle and deer could be identified by standard fingerprinting methods used for library-based microbial source tracking (repetitive element PCR and pulsed-field gel electrophoresis) in relation to microarray-based analysis of genome content. Our results show that patterns of gene presence or absence were more useful for distinguishing E. coli isolates from different sources than traditional fingerprinting methods, particularly in the case of human strains. Host-associated differences in genome composition included the presence or absence of mobile IS1 elements as well as genes encoding the ferric dicitrate iron transporter (fec), E. coli common pilus (ECP), type 1 fimbriae and the CRISPR associated cas proteins. Many of these differences occurred in regions of the E. coli chromosome previously shown to be “hot spots” for the integration of horizontally-acquired DNA. PCR primers designed to amplify the IS1 and fec loci confirmed array results and demonstrated the ease with which gene presence/absence data can be converted into a diagnostic assay. The data presented here suggest that, despite the high level of genetic diversity observed among isolates by PFGE, human-derived strains may constitute a distinct ecotype distinguished by multiple potential library-independent source tracking markers.
Project description:Escherichia coli bloodstream infections are common and associated with high mortality. A key feature of E. coli is the lipopolysaccharide (LPS) O-antigen, which contributes to immune evasion during invasive infection. We analyzed serial E. coli isolates from patients with relapsed bacteremia and identified frequent disruption of O-antigen synthesis due to mutations in wbbL, resulting in a rough LPS (R-LPS) phenotype. E. coli with rough LPS isolates were more serum sensitive and less pathogenic in mice. Despite this apparent attenuation, 11 of 66 (18%) E. coli sequence type 131 bloodstream isolates in our cohort lacked O-antigen and were associated with significantly worse clinical outcomes, including septic shock and mortality. Using a recurrent bacteremia model, we show that R-LPS isolates partially evade protective immunity generated against smooth-LPS E. coli, highlighting the importance of host immune context in invasive disease.
Project description:ChIP-seq was performed to map the association of FLAG-tagged CRP across the Escherichia coli MG1655 chromosome during exponential phase growth in LB alone or LB supplemented with cAMP or arabinose and IPTG. ChIP-seq was also performed to map the association of CRP across the Escherichia coli MG1655 chromosome using a CRP antibody during exponential phase growth in LB alone.
Project description:The goal of this study is to compare gene expression data for a well known model organism (Escherichia coli) using different technologies (NGS here, microarray from GSE48776).