Project description:Laboratory adaptive evolution experiments were conducted using serial passage of E. coli in M9 minimal medium supplemented with either 2 g/L of lactate for 60 days or 2 g/L of glycerol for 44 days. 7 parallel evolution strains were generated for growth on lactate and 7 parallel evolution strains were generated for growth on glycerol. Affymetrix arrays were used to study the time-course change in gene expression from unevolved E. coli (day 0) to a midpoint evolved strain (day 20) and evolutionary endpoints
Project description:Laboratory adaptive evolution experiments were conducted using serial passage of E. coli in M9 minimal medium supplemented with either 2 g/L of lactate for 60 days or 2 g/L of glycerol for 44 days. 7 parallel evolution strains were generated for growth on lactate and 7 parallel evolution strains were generated for growth on glycerol. Affymetrix arrays were used to study the time-course change in gene expression from unevolved E. coli (day 0) to a midpoint evolved strain (day 20) and evolutionary endpoints Biological replicate arrays were conducted for each of the time points tested for the different evolution strains
Project description:Using a synthetic biosensor to couple production of a specific metabolite with cell growth, we spontaneously evolved cells under the selective condition toward the acquisition of genotypes that optimally reallocated cellular resources. Using 3-hydroxypropionic acid (3-HP) production from glycerol in Escherichia coli as a model system, we determined that spontaneous mutations in the conserved regions of proteins involved in global transcriptional regulation altered the expression of several genes associated with central carbon metabolism. Our study provides a new perspective on adaptive laboratory evolution (ALE) using synthetic biosensors, thereby supporting future efforts in metabolic pathway optimization.
Project description:To understand the mechanism of isopropanol tolerance of Escherichia coli for improvement of isopropanol production, we performed genome re-sequencing and transcriptome analysis of isopropanol tolerant E. coli strains obtained from parallel adaptive laboratory evolution under IPA stress.
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:Glycerol is an attractive feedstock for biofuels since it accumulates as a byproduct during biodiesel operations; hence, it is interesting to consider converting glycerol to hydrogen using the formate hydrogen lyase system of Escherichia coli which converts pyruvate to hydrogen. Starting with Escherichia coli BW25113 frdC that lacks fumarate reductase to eliminate the negative effect of accumulated hydrogen on glycerol fermentation and by using both adaptive evolution and chemical mutagenesis combined with a selection method based on increased growth on glycerol, we obtained an improved strain, HW2, that produces 20-fold more hydrogen in glycerol medium (0.68 mmol/L/h) compared to that of frdC mutant. HW2 also grows 5-fold faster (0.25 1/h) than BW25113 frdC on glycerol, so it achieves a reasonable growth rate. Corroborating the increase in hydrogen production, glycerol dehydrogenase activity in HW2 increased 4-fold compared to BW25113 frdC. In addition, a whole-transcriptome study revealed that several pathways that would decrease hydrogen yields were repressed in HW2 (fbp, focA, and gatYZ) while a beneficial pathway, eno which encodes enolase was induced.
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:This study explores the effects of glycerol, on whole genome expression of Escherichia coli. DNA microarray analysis imply that E. coli in the presence of glycerol generates acidic metabolites to which it adapts by upregulation of genes involved in acid stress and by simultaneously downregulating genes involved in high pH stress.
Project description:Using a synthetic biosensor to couple production of a specific metabolite with cell growth, we spontaneously evolved cells under the selective condition toward the acquisition of genotypes that optimally reallocated cellular resources. Using 3-hydroxypropionic acid (3-HP) production from glycerol in Escherichia coli as a model system, we determined that spontaneous mutations in the conserved regions of proteins involved in global transcriptional regulation altered the expression of several genes associated with central carbon metabolism. Our study provides a new perspective on adaptive laboratory evolution (ALE) using synthetic biosensors, thereby supporting future efforts in metabolic pathway optimization.
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).